/*
 * Copyright (c) 2006, 2007, 2008 QLogic Corporation. All rights reserved.
 * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/idr.h>
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
#include <linux/bitmap.h>
#include <linux/slab.h>

#include "ipath_kernel.h"
#include "ipath_verbs.h"

static void ipath_update_pio_bufs(struct ipath_devdata *);

const char *ipath_get_unit_name(int unit)
{
        static char iname[16];
        snprintf(iname, sizeof iname, "infinipath%u", unit);
        return iname;
}

#define DRIVER_LOAD_MSG "QLogic " IPATH_DRV_NAME " loaded: "
#define PFX IPATH_DRV_NAME ": "

/*
 * The size has to be longer than this string, so we can append
 * board/chip information to it in the init code.
 */
const char ib_ipath_version[] = IPATH_IDSTR "\n";

static struct idr unit_table;
DEFINE_SPINLOCK(ipath_devs_lock);
LIST_HEAD(ipath_dev_list);

wait_queue_head_t ipath_state_wait;

unsigned ipath_debug = __IPATH_INFO;

module_param_named(debug, ipath_debug, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(debug, "mask for debug prints");
EXPORT_SYMBOL_GPL(ipath_debug);

unsigned ipath_mtu4096 = 1; /* max 4KB IB mtu by default, if supported */
module_param_named(mtu4096, ipath_mtu4096, uint, S_IRUGO);
MODULE_PARM_DESC(mtu4096, "enable MTU of 4096 bytes, if supported");

static unsigned ipath_hol_timeout_ms = 13000;
module_param_named(hol_timeout_ms, ipath_hol_timeout_ms, uint, S_IRUGO);
MODULE_PARM_DESC(hol_timeout_ms,
        "duration of user app suspension after link failure");

unsigned ipath_linkrecovery = 1;
module_param_named(linkrecovery, ipath_linkrecovery, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(linkrecovery, "enable workaround for link recovery issue");

MODULE_LICENSE("GPL");
MODULE_AUTHOR("QLogic <support@qlogic.com>");
MODULE_DESCRIPTION("QLogic InfiniPath driver");

/*
 * Table to translate the LINKTRAININGSTATE portion of
 * IBCStatus to a human-readable form.
 */
const char *ipath_ibcstatus_str[] = {
        "Disabled",
        "LinkUp",
        "PollActive",
        "PollQuiet",
        "SleepDelay",
        "SleepQuiet",
        "LState6",              /* unused */
        "LState7",              /* unused */
        "CfgDebounce",
        "CfgRcvfCfg",
        "CfgWaitRmt",
        "CfgIdle",
        "RecovRetrain",
        "CfgTxRevLane",         /* unused before IBA7220 */
        "RecovWaitRmt",
        "RecovIdle",
        /* below were added for IBA7220 */
        "CfgEnhanced",
        "CfgTest",
        "CfgWaitRmtTest",
        "CfgWaitCfgEnhanced",
        "SendTS_T",
        "SendTstIdles",
        "RcvTS_T",
        "SendTst_TS1s",
        "LTState18", "LTState19", "LTState1A", "LTState1B",
        "LTState1C", "LTState1D", "LTState1E", "LTState1F"
};

static void __devexit ipath_remove_one(struct pci_dev *);
static int __devinit ipath_init_one(struct pci_dev *,
                                    const struct pci_device_id *);

/* Only needed for registration, nothing else needs this info */
#define PCI_VENDOR_ID_PATHSCALE 0x1fc1
#define PCI_DEVICE_ID_INFINIPATH_HT 0xd

/* Number of seconds before our card status check...  */
#define STATUS_TIMEOUT 60

static const struct pci_device_id ipath_pci_tbl[] = {
        { PCI_DEVICE(PCI_VENDOR_ID_PATHSCALE, PCI_DEVICE_ID_INFINIPATH_HT) },
        { 0, }
};

MODULE_DEVICE_TABLE(pci, ipath_pci_tbl);

static struct pci_driver ipath_driver = {
        .name = IPATH_DRV_NAME,
        .probe = ipath_init_one,
        .remove = __devexit_p(ipath_remove_one),
        .id_table = ipath_pci_tbl,
        .driver = {
                .groups = ipath_driver_attr_groups,
        },
};

static inline void read_bars(struct ipath_devdata *dd, struct pci_dev *dev,
                             u32 *bar0, u32 *bar1)
{
        int ret;

        ret = pci_read_config_dword(dev, PCI_BASE_ADDRESS_0, bar0);
        if (ret)
                ipath_dev_err(dd, "failed to read bar0 before enable: "
                              "error %d\n", -ret);

        ret = pci_read_config_dword(dev, PCI_BASE_ADDRESS_1, bar1);
        if (ret)
                ipath_dev_err(dd, "failed to read bar1 before enable: "
                              "error %d\n", -ret);

        ipath_dbg("Read bar0 %x bar1 %x\n", *bar0, *bar1);
}

static void ipath_free_devdata(struct pci_dev *pdev,
                               struct ipath_devdata *dd)
{
        unsigned long flags;

        pci_set_drvdata(pdev, NULL);

        if (dd->ipath_unit != -1) {
                spin_lock_irqsave(&ipath_devs_lock, flags);
                idr_remove(&unit_table, dd->ipath_unit);
                list_del(&dd->ipath_list);
                spin_unlock_irqrestore(&ipath_devs_lock, flags);
        }
        vfree(dd);
}

static struct ipath_devdata *ipath_alloc_devdata(struct pci_dev *pdev)
{
        unsigned long flags;
        struct ipath_devdata *dd;
        int ret;

        if (!idr_pre_get(&unit_table, GFP_KERNEL)) {
                dd = ERR_PTR(-ENOMEM);
                goto bail;
        }

        dd = vzalloc(sizeof(*dd));
        if (!dd) {
                dd = ERR_PTR(-ENOMEM);
                goto bail;
        }
        dd->ipath_unit = -1;

        spin_lock_irqsave(&ipath_devs_lock, flags);

        ret = idr_get_new(&unit_table, dd, &dd->ipath_unit);
        if (ret < 0) {
                printk(KERN_ERR IPATH_DRV_NAME
                       ": Could not allocate unit ID: error %d\n", -ret);
                ipath_free_devdata(pdev, dd);
                dd = ERR_PTR(ret);
                goto bail_unlock;
        }

        dd->pcidev = pdev;
        pci_set_drvdata(pdev, dd);

        list_add(&dd->ipath_list, &ipath_dev_list);

bail_unlock:
        spin_unlock_irqrestore(&ipath_devs_lock, flags);

bail:
        return dd;
}

static inline struct ipath_devdata *__ipath_lookup(int unit)
{
        return idr_find(&unit_table, unit);
}

struct ipath_devdata *ipath_lookup(int unit)
{
        struct ipath_devdata *dd;
        unsigned long flags;

        spin_lock_irqsave(&ipath_devs_lock, flags);
        dd = __ipath_lookup(unit);
        spin_unlock_irqrestore(&ipath_devs_lock, flags);

        return dd;
}

int ipath_count_units(int *npresentp, int *nupp, int *maxportsp)
{
        int nunits, npresent, nup;
        struct ipath_devdata *dd;
        unsigned long flags;
        int maxports;

        nunits = npresent = nup = maxports = 0;

        spin_lock_irqsave(&ipath_devs_lock, flags);

        list_for_each_entry(dd, &ipath_dev_list, ipath_list) {
                nunits++;
                if ((dd->ipath_flags & IPATH_PRESENT) && dd->ipath_kregbase)
                        npresent++;
                if (dd->ipath_lid &&
                    !(dd->ipath_flags & (IPATH_DISABLED | IPATH_LINKDOWN
                                         | IPATH_LINKUNK)))
                        nup++;
                if (dd->ipath_cfgports > maxports)
                        maxports = dd->ipath_cfgports;
        }

        spin_unlock_irqrestore(&ipath_devs_lock, flags);

        if (npresentp)
                *npresentp = npresent;
        if (nupp)
                *nupp = nup;
        if (maxportsp)
                *maxportsp = maxports;

        return nunits;
}

/*
 * These next two routines are placeholders in case we don't have per-arch
 * code for controlling write combining.  If explicit control of write
 * combining is not available, performance will probably be awful.
 */

int __attribute__((weak)) ipath_enable_wc(struct ipath_devdata *dd)
{
        return -EOPNOTSUPP;
}

void __attribute__((weak)) ipath_disable_wc(struct ipath_devdata *dd)
{
}

/*
 * Perform a PIO buffer bandwidth write test, to verify proper system
 * configuration.  Even when all the setup calls work, occasionally
 * BIOS or other issues can prevent write combining from working, or
 * can cause other bandwidth problems to the chip.
 *
 * This test simply writes the same buffer over and over again, and
 * measures close to the peak bandwidth to the chip (not testing
 * data bandwidth to the wire).   On chips that use an address-based
 * trigger to send packets to the wire, this is easy.  On chips that
 * use a count to trigger, we want to make sure that the packet doesn't
 * go out on the wire, or trigger flow control checks.
 */
static void ipath_verify_pioperf(struct ipath_devdata *dd)
{
        u32 pbnum, cnt, lcnt;
        u32 __iomem *piobuf;
        u32 *addr;
        u64 msecs, emsecs;

        piobuf = ipath_getpiobuf(dd, 0, &pbnum);
        if (!piobuf) {
                dev_info(&dd->pcidev->dev,
                        "No PIObufs for checking perf, skipping\n");
                return;
        }

        /*
         * Enough to give us a reasonable test, less than piobuf size, and
         * likely multiple of store buffer length.
         */
        cnt = 1024;

        addr = vmalloc(cnt);
        if (!addr) {
                dev_info(&dd->pcidev->dev,
                        "Couldn't get memory for checking PIO perf,"
                        " skipping\n");
                goto done;
        }

        preempt_disable();  /* we want reasonably accurate elapsed time */
        msecs = 1 + jiffies_to_msecs(jiffies);
        for (lcnt = 0; lcnt < 10000U; lcnt++) {
                /* wait until we cross msec boundary */
                if (jiffies_to_msecs(jiffies) >= msecs)
                        break;
                udelay(1);
        }

        ipath_disable_armlaunch(dd);

        /*
         * length 0, no dwords actually sent, and mark as VL15
         * on chips where that may matter (due to IB flowcontrol)
         */
        if ((dd->ipath_flags & IPATH_HAS_PBC_CNT))
                writeq(1UL << 63, piobuf);
        else
                writeq(0, piobuf);
        ipath_flush_wc();

        /*
         * this is only roughly accurate, since even with preempt we
         * still take interrupts that could take a while.   Running for
         * >= 5 msec seems to get us "close enough" to accurate values
         */
        msecs = jiffies_to_msecs(jiffies);
        for (emsecs = lcnt = 0; emsecs <= 5UL; lcnt++) {
                __iowrite32_copy(piobuf + 64, addr, cnt >> 2);
                emsecs = jiffies_to_msecs(jiffies) - msecs;
        }

        /* 1 GiB/sec, slightly over IB SDR line rate */
        if (lcnt < (emsecs * 1024U))
                ipath_dev_err(dd,
                        "Performance problem: bandwidth to PIO buffers is "
                        "only %u MiB/sec\n",
                        lcnt / (u32) emsecs);
        else
                ipath_dbg("PIO buffer bandwidth %u MiB/sec is OK\n",
                        lcnt / (u32) emsecs);

        preempt_enable();

        vfree(addr);

done:
        /* disarm piobuf, so it's available again */
        ipath_disarm_piobufs(dd, pbnum, 1);
        ipath_enable_armlaunch(dd);
}

static void cleanup_device(struct ipath_devdata *dd);

static int __devinit ipath_init_one(struct pci_dev *pdev,
                                    const struct pci_device_id *ent)
{
        int ret, len, j;
        struct ipath_devdata *dd;
        unsigned long long addr;
        u32 bar0 = 0, bar1 = 0;
        u8 rev;

        dd = ipath_alloc_devdata(pdev);
        if (IS_ERR(dd)) {
                ret = PTR_ERR(dd);
                printk(KERN_ERR IPATH_DRV_NAME
                       ": Could not allocate devdata: error %d\n", -ret);
                goto bail;
        }

        ipath_cdbg(VERBOSE, "initializing unit #%u\n", dd->ipath_unit);

        ret = pci_enable_device(pdev);
        if (ret) {
                /* This can happen iff:
                 *
                 * We did a chip reset, and then failed to reprogram the
                 * BAR, or the chip reset due to an internal error.  We then
                 * unloaded the driver and reloaded it.
                 *
                 * Both reset cases set the BAR back to initial state.  For
                 * the latter case, the AER sticky error bit at offset 0x718
                 * should be set, but the Linux kernel doesn't yet know
                 * about that, it appears.  If the original BAR was retained
                 * in the kernel data structures, this may be OK.
                 */
                ipath_dev_err(dd, "enable unit %d failed: error %d\n",
                              dd->ipath_unit, -ret);
                goto bail_devdata;
        }
        addr = pci_resource_start(pdev, 0);
        len = pci_resource_len(pdev, 0);
        ipath_cdbg(VERBOSE, "regbase (0) %llx len %d irq %d, vend %x/%x "
                   "driver_data %lx\n", addr, len, pdev->irq, ent->vendor,
                   ent->device, ent->driver_data);

        read_bars(dd, pdev, &bar0, &bar1);

        if (!bar1 && !(bar0 & ~0xf)) {
                if (addr) {
                        dev_info(&pdev->dev, "BAR is 0 (probable RESET), "
                                 "rewriting as %llx\n", addr);
                        ret = pci_write_config_dword(
                                pdev, PCI_BASE_ADDRESS_0, addr);
                        if (ret) {
                                ipath_dev_err(dd, "rewrite of BAR0 "
                                              "failed: err %d\n", -ret);
                                goto bail_disable;
                        }
                        ret = pci_write_config_dword(
                                pdev, PCI_BASE_ADDRESS_1, addr >> 32);
                        if (ret) {
                                ipath_dev_err(dd, "rewrite of BAR1 "
                                              "failed: err %d\n", -ret);
                                goto bail_disable;
                        }
                } else {
                        ipath_dev_err(dd, "BAR is 0 (probable RESET), "
                                      "not usable until reboot\n");
                        ret = -ENODEV;
                        goto bail_disable;
                }
        }

        ret = pci_request_regions(pdev, IPATH_DRV_NAME);
        if (ret) {
                dev_info(&pdev->dev, "pci_request_regions unit %u fails: "
                         "err %d\n", dd->ipath_unit, -ret);
                goto bail_disable;
        }

        ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
        if (ret) {
                /*
                 * if the 64 bit setup fails, try 32 bit.  Some systems
                 * do not setup 64 bit maps on systems with 2GB or less
                 * memory installed.
                 */
                ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
                if (ret) {
                        dev_info(&pdev->dev,
                                "Unable to set DMA mask for unit %u: %d\n",
                                dd->ipath_unit, ret);
                        goto bail_regions;
                }
                else {
                        ipath_dbg("No 64bit DMA mask, used 32 bit mask\n");
                        ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
                        if (ret)
                                dev_info(&pdev->dev,
                                        "Unable to set DMA consistent mask "
                                        "for unit %u: %d\n",
                                        dd->ipath_unit, ret);

                }
        }
        else {
                ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
                if (ret)
                        dev_info(&pdev->dev,
                                "Unable to set DMA consistent mask "
                                "for unit %u: %d\n",
                                dd->ipath_unit, ret);
        }

        pci_set_master(pdev);

        /*
         * Save BARs to rewrite after device reset.  Save all 64 bits of
         * BAR, just in case.
         */
        dd->ipath_pcibar0 = addr;
        dd->ipath_pcibar1 = addr >> 32;
        dd->ipath_deviceid = ent->device;       /* save for later use */
        dd->ipath_vendorid = ent->vendor;

        /* setup the chip-specific functions, as early as possible. */
        switch (ent->device) {
        case PCI_DEVICE_ID_INFINIPATH_HT:
                ipath_init_iba6110_funcs(dd);
                break;

        default:
                ipath_dev_err(dd, "Found unknown QLogic deviceid 0x%x, "
                              "failing\n", ent->device);
                return -ENODEV;
        }

        for (j = 0; j < 6; j++) {
                if (!pdev->resource[j].start)
                        continue;
                ipath_cdbg(VERBOSE, "BAR %d %pR, len %llx\n",
                           j, &pdev->resource[j],
                           (unsigned long long)pci_resource_len(pdev, j));
        }

        if (!addr) {
                ipath_dev_err(dd, "No valid address in BAR 0!\n");
                ret = -ENODEV;
                goto bail_regions;
        }

        ret = pci_read_config_byte(pdev, PCI_REVISION_ID, &rev);
        if (ret) {
                ipath_dev_err(dd, "Failed to read PCI revision ID unit "
                              "%u: err %d\n", dd->ipath_unit, -ret);
                goto bail_regions;      /* shouldn't ever happen */
        }
        dd->ipath_pcirev = rev;

#if defined(__powerpc__)
        /* There isn't a generic way to specify writethrough mappings */
        dd->ipath_kregbase = __ioremap(addr, len,
                (_PAGE_NO_CACHE|_PAGE_WRITETHRU));
#else
        dd->ipath_kregbase = ioremap_nocache(addr, len);
#endif

        if (!dd->ipath_kregbase) {
                ipath_dbg("Unable to map io addr %llx to kvirt, failing\n",
                          addr);
                ret = -ENOMEM;
                goto bail_iounmap;
        }
        dd->ipath_kregend = (u64 __iomem *)
                ((void __iomem *)dd->ipath_kregbase + len);
        dd->ipath_physaddr = addr;      /* used for io_remap, etc. */
        /* for user mmap */
        ipath_cdbg(VERBOSE, "mapped io addr %llx to kregbase %p\n",
                   addr, dd->ipath_kregbase);

        if (dd->ipath_f_bus(dd, pdev))
                ipath_dev_err(dd, "Failed to setup config space; "
                              "continuing anyway\n");

        /*
         * set up our interrupt handler; IRQF_SHARED probably not needed,
         * since MSI interrupts shouldn't be shared but won't  hurt for now.
         * check 0 irq after we return from chip-specific bus setup, since
         * that can affect this due to setup
         */
        if (!dd->ipath_irq)
                ipath_dev_err(dd, "irq is 0, BIOS error?  Interrupts won't "
                              "work\n");
        else {
                ret = request_irq(dd->ipath_irq, ipath_intr, IRQF_SHARED,
                                  IPATH_DRV_NAME, dd);
                if (ret) {
                        ipath_dev_err(dd, "Couldn't setup irq handler, "
                                      "irq=%d: %d\n", dd->ipath_irq, ret);
                        goto bail_iounmap;
                }
        }

        ret = ipath_init_chip(dd, 0);   /* do the chip-specific init */
        if (ret)
                goto bail_irqsetup;

        ret = ipath_enable_wc(dd);

        if (ret) {
                ipath_dev_err(dd, "Write combining not enabled "
                              "(err %d): performance may be poor\n",
                              -ret);
                ret = 0;
        }

        ipath_verify_pioperf(dd);

        ipath_device_create_group(&pdev->dev, dd);
        ipathfs_add_device(dd);
        ipath_user_add(dd);
        ipath_diag_add(dd);
        ipath_register_ib_device(dd);

        goto bail;

bail_irqsetup:
        cleanup_device(dd);

        if (dd->ipath_irq)
                dd->ipath_f_free_irq(dd);

        if (dd->ipath_f_cleanup)
                dd->ipath_f_cleanup(dd);

bail_iounmap:
        iounmap((volatile void __iomem *) dd->ipath_kregbase);

bail_regions:
        pci_release_regions(pdev);

bail_disable:
        pci_disable_device(pdev);

bail_devdata:
        ipath_free_devdata(pdev, dd);

bail:
        return ret;
}

static void cleanup_device(struct ipath_devdata *dd)
{
        int port;
        struct ipath_portdata **tmp;
        unsigned long flags;

        if (*dd->ipath_statusp & IPATH_STATUS_CHIP_PRESENT) {
                /* can't do anything more with chip; needs re-init */
                *dd->ipath_statusp &= ~IPATH_STATUS_CHIP_PRESENT;
                if (dd->ipath_kregbase) {
                        /*
                         * if we haven't already cleaned up before these are
                         * to ensure any register reads/writes "fail" until
                         * re-init
                         */
                        dd->ipath_kregbase = NULL;
                        dd->ipath_uregbase = 0;
                        dd->ipath_sregbase = 0;
                        dd->ipath_cregbase = 0;
                        dd->ipath_kregsize = 0;
                }
                ipath_disable_wc(dd);
        }

        if (dd->ipath_spectriggerhit)
                dev_info(&dd->pcidev->dev, "%lu special trigger hits\n",
                         dd->ipath_spectriggerhit);

        if (dd->ipath_pioavailregs_dma) {
                dma_free_coherent(&dd->pcidev->dev, PAGE_SIZE,
                                  (void *) dd->ipath_pioavailregs_dma,
                                  dd->ipath_pioavailregs_phys);
                dd->ipath_pioavailregs_dma = NULL;
        }
        if (dd->ipath_dummy_hdrq) {
                dma_free_coherent(&dd->pcidev->dev,
                        dd->ipath_pd[0]->port_rcvhdrq_size,
                        dd->ipath_dummy_hdrq, dd->ipath_dummy_hdrq_phys);
                dd->ipath_dummy_hdrq = NULL;
        }

        if (dd->ipath_pageshadow) {
                struct page **tmpp = dd->ipath_pageshadow;
                dma_addr_t *tmpd = dd->ipath_physshadow;
                int i, cnt = 0;

                ipath_cdbg(VERBOSE, "Unlocking any expTID pages still "
                           "locked\n");
                for (port = 0; port < dd->ipath_cfgports; port++) {
                        int port_tidbase = port * dd->ipath_rcvtidcnt;
                        int maxtid = port_tidbase + dd->ipath_rcvtidcnt;
                        for (i = port_tidbase; i < maxtid; i++) {
                                if (!tmpp[i])
                                        continue;
                                pci_unmap_page(dd->pcidev, tmpd[i],
                                        PAGE_SIZE, PCI_DMA_FROMDEVICE);
                                ipath_release_user_pages(&tmpp[i], 1);
                                tmpp[i] = NULL;
                                cnt++;
                        }
                }
                if (cnt) {
                        ipath_stats.sps_pageunlocks += cnt;
                        ipath_cdbg(VERBOSE, "There were still %u expTID "
                                   "entries locked\n", cnt);
                }
                if (ipath_stats.sps_pagelocks ||
                    ipath_stats.sps_pageunlocks)
                        ipath_cdbg(VERBOSE, "%llu pages locked, %llu "
                                   "unlocked via ipath_m{un}lock\n",
                                   (unsigned long long)
                                   ipath_stats.sps_pagelocks,
                                   (unsigned long long)
                                   ipath_stats.sps_pageunlocks);

                ipath_cdbg(VERBOSE, "Free shadow page tid array at %p\n",
                           dd->ipath_pageshadow);
                tmpp = dd->ipath_pageshadow;
                dd->ipath_pageshadow = NULL;
                vfree(tmpp);

                dd->ipath_egrtidbase = NULL;
        }

        /*
         * free any resources still in use (usually just kernel ports)
         * at unload; we do for portcnt, because that's what we allocate.
         * We acquire lock to be really paranoid that ipath_pd isn't being
         * accessed from some interrupt-related code (that should not happen,
         * but best to be sure).
         */
        spin_lock_irqsave(&dd->ipath_uctxt_lock, flags);
        tmp = dd->ipath_pd;
        dd->ipath_pd = NULL;
        spin_unlock_irqrestore(&dd->ipath_uctxt_lock, flags);
        for (port = 0; port < dd->ipath_portcnt; port++) {
                struct ipath_portdata *pd = tmp[port];
                tmp[port] = NULL; /* debugging paranoia */
                ipath_free_pddata(dd, pd);
        }
        kfree(tmp);
}

static void __devexit ipath_remove_one(struct pci_dev *pdev)
{
        struct ipath_devdata *dd = pci_get_drvdata(pdev);

        ipath_cdbg(VERBOSE, "removing, pdev=%p, dd=%p\n", pdev, dd);

        /*
         * disable the IB link early, to be sure no new packets arrive, which
         * complicates the shutdown process
         */
        ipath_shutdown_device(dd);

        flush_workqueue(ib_wq);

        if (dd->verbs_dev)
                ipath_unregister_ib_device(dd->verbs_dev);

        ipath_diag_remove(dd);
        ipath_user_remove(dd);
        ipathfs_remove_device(dd);
        ipath_device_remove_group(&pdev->dev, dd);

        ipath_cdbg(VERBOSE, "Releasing pci memory regions, dd %p, "
                   "unit %u\n", dd, (u32) dd->ipath_unit);

        cleanup_device(dd);

        /*
         * turn off rcv, send, and interrupts for all ports, all drivers
         * should also hard reset the chip here?
         * free up port 0 (kernel) rcvhdr, egr bufs, and eventually tid bufs
         * for all versions of the driver, if they were allocated
         */
        if (dd->ipath_irq) {
                ipath_cdbg(VERBOSE, "unit %u free irq %d\n",
                           dd->ipath_unit, dd->ipath_irq);
                dd->ipath_f_free_irq(dd);
        } else
                ipath_dbg("irq is 0, not doing free_irq "
                          "for unit %u\n", dd->ipath_unit);
        /*
         * we check for NULL here, because it's outside
         * the kregbase check, and we need to call it
         * after the free_irq.  Thus it's possible that
         * the function pointers were never initialized.
         */
        if (dd->ipath_f_cleanup)
                /* clean up chip-specific stuff */
                dd->ipath_f_cleanup(dd);

        ipath_cdbg(VERBOSE, "Unmapping kregbase %p\n", dd->ipath_kregbase);
        iounmap((volatile void __iomem *) dd->ipath_kregbase);
        pci_release_regions(pdev);
        ipath_cdbg(VERBOSE, "calling pci_disable_device\n");
        pci_disable_device(pdev);

        ipath_free_devdata(pdev, dd);
}

/* general driver use */
DEFINE_MUTEX(ipath_mutex);

static DEFINE_SPINLOCK(ipath_pioavail_lock);

/**
 * ipath_disarm_piobufs - cancel a range of PIO buffers
 * @dd: the infinipath device
 * @first: the first PIO buffer to cancel
 * @cnt: the number of PIO buffers to cancel
 *
 * cancel a range of PIO buffers, used when they might be armed, but
 * not triggered.  Used at init to ensure buffer state, and also user
 * process close, in case it died while writing to a PIO buffer
 * Also after errors.
 */
void ipath_disarm_piobufs(struct ipath_devdata *dd, unsigned first,
                          unsigned cnt)
{
        unsigned i, last = first + cnt;
        unsigned long flags;

        ipath_cdbg(PKT, "disarm %u PIObufs first=%u\n", cnt, first);
        for (i = first; i < last; i++) {
                spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
                /*
                 * The disarm-related bits are write-only, so it
                 * is ok to OR them in with our copy of sendctrl
                 * while we hold the lock.
                 */
                ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
                        dd->ipath_sendctrl | INFINIPATH_S_DISARM |
                        (i << INFINIPATH_S_DISARMPIOBUF_SHIFT));
                /* can't disarm bufs back-to-back per iba7220 spec */
                ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
                spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
        }
        /* on some older chips, update may not happen after cancel */
        ipath_force_pio_avail_update(dd);
}

/**
 * ipath_wait_linkstate - wait for an IB link state change to occur
 * @dd: the infinipath device
 * @state: the state to wait for
 * @msecs: the number of milliseconds to wait
 *
 * wait up to msecs milliseconds for IB link state change to occur for
 * now, take the easy polling route.  Currently used only by
 * ipath_set_linkstate.  Returns 0 if state reached, otherwise
 * -ETIMEDOUT state can have multiple states set, for any of several
 * transitions.
 */
int ipath_wait_linkstate(struct ipath_devdata *dd, u32 state, int msecs)
{
        dd->ipath_state_wanted = state;
        wait_event_interruptible_timeout(ipath_state_wait,
                                         (dd->ipath_flags & state),
                                         msecs_to_jiffies(msecs));
        dd->ipath_state_wanted = 0;

        if (!(dd->ipath_flags & state)) {
                u64 val;
                ipath_cdbg(VERBOSE, "Didn't reach linkstate %s within %u"
                           " ms\n",
                           /* test INIT ahead of DOWN, both can be set */
                           (state & IPATH_LINKINIT) ? "INIT" :
                           ((state & IPATH_LINKDOWN) ? "DOWN" :
                            ((state & IPATH_LINKARMED) ? "ARM" : "ACTIVE")),
                           msecs);
                val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_ibcstatus);
                ipath_cdbg(VERBOSE, "ibcc=%llx ibcstatus=%llx (%s)\n",
                           (unsigned long long) ipath_read_kreg64(
                                   dd, dd->ipath_kregs->kr_ibcctrl),
                           (unsigned long long) val,
                           ipath_ibcstatus_str[val & dd->ibcs_lts_mask]);
        }
        return (dd->ipath_flags & state) ? 0 : -ETIMEDOUT;
}

static void decode_sdma_errs(struct ipath_devdata *dd, ipath_err_t err,
        char *buf, size_t blen)
{
        static const struct {
                ipath_err_t err;
                const char *msg;
        } errs[] = {
                { INFINIPATH_E_SDMAGENMISMATCH, "SDmaGenMismatch" },
                { INFINIPATH_E_SDMAOUTOFBOUND, "SDmaOutOfBound" },
                { INFINIPATH_E_SDMATAILOUTOFBOUND, "SDmaTailOutOfBound" },
                { INFINIPATH_E_SDMABASE, "SDmaBase" },
                { INFINIPATH_E_SDMA1STDESC, "SDma1stDesc" },
                { INFINIPATH_E_SDMARPYTAG, "SDmaRpyTag" },
                { INFINIPATH_E_SDMADWEN, "SDmaDwEn" },
                { INFINIPATH_E_SDMAMISSINGDW, "SDmaMissingDw" },
                { INFINIPATH_E_SDMAUNEXPDATA, "SDmaUnexpData" },
                { INFINIPATH_E_SDMADESCADDRMISALIGN, "SDmaDescAddrMisalign" },
                { INFINIPATH_E_SENDBUFMISUSE, "SendBufMisuse" },
                { INFINIPATH_E_SDMADISABLED, "SDmaDisabled" },
        };
        int i;
        int expected;
        size_t bidx = 0;

        for (i = 0; i < ARRAY_SIZE(errs); i++) {
                expected = (errs[i].err != INFINIPATH_E_SDMADISABLED) ? 0 :
                        test_bit(IPATH_SDMA_ABORTING, &dd->ipath_sdma_status);
                if ((err & errs[i].err) && !expected)
                        bidx += snprintf(buf + bidx, blen - bidx,
                                         "%s ", errs[i].msg);
        }
}

/*
 * Decode the error status into strings, deciding whether to always
 * print * it or not depending on "normal packet errors" vs everything
 * else.   Return 1 if "real" errors, otherwise 0 if only packet
 * errors, so caller can decide what to print with the string.
 */
int ipath_decode_err(struct ipath_devdata *dd, char *buf, size_t blen,
        ipath_err_t err)
{
        int iserr = 1;
        *buf = '\0';
        if (err & INFINIPATH_E_PKTERRS) {
                if (!(err & ~INFINIPATH_E_PKTERRS))
                        iserr = 0; // if only packet errors.
                if (ipath_debug & __IPATH_ERRPKTDBG) {
                        if (err & INFINIPATH_E_REBP)
                                strlcat(buf, "EBP ", blen);
                        if (err & INFINIPATH_E_RVCRC)
                                strlcat(buf, "VCRC ", blen);
                        if (err & INFINIPATH_E_RICRC) {
                                strlcat(buf, "CRC ", blen);
                                // clear for check below, so only once
                                err &= INFINIPATH_E_RICRC;
                        }
                        if (err & INFINIPATH_E_RSHORTPKTLEN)
                                strlcat(buf, "rshortpktlen ", blen);
                        if (err & INFINIPATH_E_SDROPPEDDATAPKT)
                                strlcat(buf, "sdroppeddatapkt ", blen);
                        if (err & INFINIPATH_E_SPKTLEN)
                                strlcat(buf, "spktlen ", blen);
                }
                if ((err & INFINIPATH_E_RICRC) &&
                        !(err&(INFINIPATH_E_RVCRC|INFINIPATH_E_REBP)))
                        strlcat(buf, "CRC ", blen);
                if (!iserr)
                        goto done;
        }
        if (err & INFINIPATH_E_RHDRLEN)
                strlcat(buf, "rhdrlen ", blen);
        if (err & INFINIPATH_E_RBADTID)
                strlcat(buf, "rbadtid ", blen);
        if (err & INFINIPATH_E_RBADVERSION)
                strlcat(buf, "rbadversion ", blen);
        if (err & INFINIPATH_E_RHDR)
                strlcat(buf, "rhdr ", blen);
        if (err & INFINIPATH_E_SENDSPECIALTRIGGER)
                strlcat(buf, "sendspecialtrigger ", blen);
        if (err & INFINIPATH_E_RLONGPKTLEN)
                strlcat(buf, "rlongpktlen ", blen);
        if (err & INFINIPATH_E_RMAXPKTLEN)
                strlcat(buf, "rmaxpktlen ", blen);
        if (err & INFINIPATH_E_RMINPKTLEN)
                strlcat(buf, "rminpktlen ", blen);
        if (err & INFINIPATH_E_SMINPKTLEN)
                strlcat(buf, "sminpktlen ", blen);
        if (err & INFINIPATH_E_RFORMATERR)
                strlcat(buf, "rformaterr ", blen);
        if (err & INFINIPATH_E_RUNSUPVL)
                strlcat(buf, "runsupvl ", blen);
        if (err & INFINIPATH_E_RUNEXPCHAR)
                strlcat(buf, "runexpchar ", blen);
        if (err & INFINIPATH_E_RIBFLOW)
                strlcat(buf, "ribflow ", blen);
        if (err & INFINIPATH_E_SUNDERRUN)
                strlcat(buf, "sunderrun ", blen);
        if (err & INFINIPATH_E_SPIOARMLAUNCH)
                strlcat(buf, "spioarmlaunch ", blen);
        if (err & INFINIPATH_E_SUNEXPERRPKTNUM)
                strlcat(buf, "sunexperrpktnum ", blen);
        if (err & INFINIPATH_E_SDROPPEDSMPPKT)
                strlcat(buf, "sdroppedsmppkt ", blen);
        if (err & INFINIPATH_E_SMAXPKTLEN)
                strlcat(buf, "smaxpktlen ", blen);
        if (err & INFINIPATH_E_SUNSUPVL)
                strlcat(buf, "sunsupVL ", blen);
        if (err & INFINIPATH_E_INVALIDADDR)
                strlcat(buf, "invalidaddr ", blen);
        if (err & INFINIPATH_E_RRCVEGRFULL)
                strlcat(buf, "rcvegrfull ", blen);
        if (err & INFINIPATH_E_RRCVHDRFULL)
                strlcat(buf, "rcvhdrfull ", blen);
        if (err & INFINIPATH_E_IBSTATUSCHANGED)
                strlcat(buf, "ibcstatuschg ", blen);

        if (err & INFINIPATH_E_RIBLOSTLINK)
                strlcat(buf, "riblostlink ", blen);
        if (err & INFINIPATH_E_HARDWARE)
                strlcat(buf, "hardware ", blen);
        if (err & INFINIPATH_E_RESET)
                strlcat(buf, "reset ", blen);
        if (err & INFINIPATH_E_SDMAERRS)
                decode_sdma_errs(dd, err, buf, blen);
        if (err & INFINIPATH_E_INVALIDEEPCMD)
                strlcat(buf, "invalideepromcmd ", blen);
done:
        return iserr;
}

/**
 * get_rhf_errstring - decode RHF errors
 * @err: the err number
 * @msg: the output buffer
 * @len: the length of the output buffer
 *
 * only used one place now, may want more later
 */
static void get_rhf_errstring(u32 err, char *msg, size_t len)
{
        /* if no errors, and so don't need to check what's first */
        *msg = '\0';

        if (err & INFINIPATH_RHF_H_ICRCERR)
                strlcat(msg, "icrcerr ", len);
        if (err & INFINIPATH_RHF_H_VCRCERR)
                strlcat(msg, "vcrcerr ", len);
        if (err & INFINIPATH_RHF_H_PARITYERR)
                strlcat(msg, "parityerr ", len);
        if (err & INFINIPATH_RHF_H_LENERR)
                strlcat(msg, "lenerr ", len);
        if (err & INFINIPATH_RHF_H_MTUERR)
                strlcat(msg, "mtuerr ", len);
        if (err & INFINIPATH_RHF_H_IHDRERR)
                /* infinipath hdr checksum error */
                strlcat(msg, "ipathhdrerr ", len);
        if (err & INFINIPATH_RHF_H_TIDERR)
                strlcat(msg, "tiderr ", len);
        if (err & INFINIPATH_RHF_H_MKERR)
                /* bad port, offset, etc. */
                strlcat(msg, "invalid ipathhdr ", len);
        if (err & INFINIPATH_RHF_H_IBERR)
                strlcat(msg, "iberr ", len);
        if (err & INFINIPATH_RHF_L_SWA)
                strlcat(msg, "swA ", len);
        if (err & INFINIPATH_RHF_L_SWB)
                strlcat(msg, "swB ", len);
}

/**
 * ipath_get_egrbuf - get an eager buffer
 * @dd: the infinipath device
 * @bufnum: the eager buffer to get
 *
 * must only be called if ipath_pd[port] is known to be allocated
 */
static inline void *ipath_get_egrbuf(struct ipath_devdata *dd, u32 bufnum)
{
        return dd->ipath_port0_skbinfo ?
                (void *) dd->ipath_port0_skbinfo[bufnum].skb->data : NULL;
}

/**
 * ipath_alloc_skb - allocate an skb and buffer with possible constraints
 * @dd: the infinipath device
 * @gfp_mask: the sk_buff SFP mask
 */
struct sk_buff *ipath_alloc_skb(struct ipath_devdata *dd,
                                gfp_t gfp_mask)
{
        struct sk_buff *skb;
        u32 len;

        /*
         * Only fully supported way to handle this is to allocate lots
         * extra, align as needed, and then do skb_reserve().  That wastes
         * a lot of memory...  I'll have to hack this into infinipath_copy
         * also.
         */

        /*
         * We need 2 extra bytes for ipath_ether data sent in the
         * key header.  In order to keep everything dword aligned,
         * we'll reserve 4 bytes.
         */
        len = dd->ipath_ibmaxlen + 4;

        if (dd->ipath_flags & IPATH_4BYTE_TID) {
                /* We need a 2KB multiple alignment, and there is no way
                 * to do it except to allocate extra and then skb_reserve
                 * enough to bring it up to the right alignment.
                 */
                len += 2047;
        }

        skb = __dev_alloc_skb(len, gfp_mask);
        if (!skb) {
                ipath_dev_err(dd, "Failed to allocate skbuff, length %u\n",
                              len);
                goto bail;
        }

        skb_reserve(skb, 4);

        if (dd->ipath_flags & IPATH_4BYTE_TID) {
                u32 una = (unsigned long)skb->data & 2047;
                if (una)
                        skb_reserve(skb, 2048 - una);
        }

bail:
        return skb;
}

static void ipath_rcv_hdrerr(struct ipath_devdata *dd,
                             u32 eflags,
                             u32 l,
                             u32 etail,
                             __le32 *rhf_addr,
                             struct ipath_message_header *hdr)
{
        char emsg[128];

        get_rhf_errstring(eflags, emsg, sizeof emsg);
        ipath_cdbg(PKT, "RHFerrs %x hdrqtail=%x typ=%u "
                   "tlen=%x opcode=%x egridx=%x: %s\n",
                   eflags, l,
                   ipath_hdrget_rcv_type(rhf_addr),
                   ipath_hdrget_length_in_bytes(rhf_addr),
                   be32_to_cpu(hdr->bth[0]) >> 24,
                   etail, emsg);

        /* Count local link integrity errors. */
        if (eflags & (INFINIPATH_RHF_H_ICRCERR | INFINIPATH_RHF_H_VCRCERR)) {
                u8 n = (dd->ipath_ibcctrl >>
                        INFINIPATH_IBCC_PHYERRTHRESHOLD_SHIFT) &
                        INFINIPATH_IBCC_PHYERRTHRESHOLD_MASK;

                if (++dd->ipath_lli_counter > n) {
                        dd->ipath_lli_counter = 0;
                        dd->ipath_lli_errors++;
                }
        }
}

/*
 * ipath_kreceive - receive a packet
 * @pd: the infinipath port
 *
 * called from interrupt handler for errors or receive interrupt
 */
void ipath_kreceive(struct ipath_portdata *pd)
{
        struct ipath_devdata *dd = pd->port_dd;
        __le32 *rhf_addr;
        void *ebuf;
        const u32 rsize = dd->ipath_rcvhdrentsize;      /* words */
        const u32 maxcnt = dd->ipath_rcvhdrcnt * rsize; /* words */
        u32 etail = -1, l, hdrqtail;
        struct ipath_message_header *hdr;
        u32 eflags, i, etype, tlen, pkttot = 0, updegr = 0, reloop = 0;
        static u64 totcalls;    /* stats, may eventually remove */
        int last;

        l = pd->port_head;
        rhf_addr = (__le32 *) pd->port_rcvhdrq + l + dd->ipath_rhf_offset;
        if (dd->ipath_flags & IPATH_NODMA_RTAIL) {
                u32 seq = ipath_hdrget_seq(rhf_addr);

                if (seq != pd->port_seq_cnt)
                        goto bail;
                hdrqtail = 0;
        } else {
                hdrqtail = ipath_get_rcvhdrtail(pd);
                if (l == hdrqtail)
                        goto bail;
                smp_rmb();
        }

reloop:
        for (last = 0, i = 1; !last; i += !last) {
                hdr = dd->ipath_f_get_msgheader(dd, rhf_addr);
                eflags = ipath_hdrget_err_flags(rhf_addr);
                etype = ipath_hdrget_rcv_type(rhf_addr);
                /* total length */
                tlen = ipath_hdrget_length_in_bytes(rhf_addr);
                ebuf = NULL;
                if ((dd->ipath_flags & IPATH_NODMA_RTAIL) ?
                    ipath_hdrget_use_egr_buf(rhf_addr) :
                    (etype != RCVHQ_RCV_TYPE_EXPECTED)) {
                        /*
                         * It turns out that the chip uses an eager buffer
                         * for all non-expected packets, whether it "needs"
                         * one or not.  So always get the index, but don't
                         * set ebuf (so we try to copy data) unless the
                         * length requires it.
                         */
                        etail = ipath_hdrget_index(rhf_addr);
                        updegr = 1;
                        if (tlen > sizeof(*hdr) ||
                            etype == RCVHQ_RCV_TYPE_NON_KD)
                                ebuf = ipath_get_egrbuf(dd, etail);
                }

                /*
                 * both tiderr and ipathhdrerr are set for all plain IB
                 * packets; only ipathhdrerr should be set.
                 */

                if (etype != RCVHQ_RCV_TYPE_NON_KD &&
                    etype != RCVHQ_RCV_TYPE_ERROR &&
                    ipath_hdrget_ipath_ver(hdr->iph.ver_port_tid_offset) !=
                    IPS_PROTO_VERSION)
                        ipath_cdbg(PKT, "Bad InfiniPath protocol version "
                                   "%x\n", etype);

                if (unlikely(eflags))
                        ipath_rcv_hdrerr(dd, eflags, l, etail, rhf_addr, hdr);
                else if (etype == RCVHQ_RCV_TYPE_NON_KD) {
                        ipath_ib_rcv(dd->verbs_dev, (u32 *)hdr, ebuf, tlen);
                        if (dd->ipath_lli_counter)
                                dd->ipath_lli_counter--;
                } else if (etype == RCVHQ_RCV_TYPE_EAGER) {
                        u8 opcode = be32_to_cpu(hdr->bth[0]) >> 24;
                        u32 qp = be32_to_cpu(hdr->bth[1]) & 0xffffff;
                        ipath_cdbg(PKT, "typ %x, opcode %x (eager, "
                                   "qp=%x), len %x; ignored\n",
                                   etype, opcode, qp, tlen);
                }
                else if (etype == RCVHQ_RCV_TYPE_EXPECTED)
                        ipath_dbg("Bug: Expected TID, opcode %x; ignored\n",
                                  be32_to_cpu(hdr->bth[0]) >> 24);
                else {
                        /*
                         * error packet, type of error unknown.
                         * Probably type 3, but we don't know, so don't
                         * even try to print the opcode, etc.
                         * Usually caused by a "bad packet", that has no
                         * BTH, when the LRH says it should.
                         */
                        ipath_cdbg(ERRPKT, "Error Pkt, but no eflags! egrbuf"
                                  " %x, len %x hdrq+%x rhf: %Lx\n",
                                  etail, tlen, l, (unsigned long long)
                                  le64_to_cpu(*(__le64 *) rhf_addr));
                        if (ipath_debug & __IPATH_ERRPKTDBG) {
                                u32 j, *d, dw = rsize-2;
                                if (rsize > (tlen>>2))
                                        dw = tlen>>2;
                                d = (u32 *)hdr;
                                printk(KERN_DEBUG "EPkt rcvhdr(%x dw):\n",
                                        dw);
                                for (j = 0; j < dw; j++)
                                        printk(KERN_DEBUG "%8x%s", d[j],
                                                (j%8) == 7 ? "\n" : " ");
                                printk(KERN_DEBUG ".\n");
                        }
                }
                l += rsize;
                if (l >= maxcnt)
                        l = 0;
                rhf_addr = (__le32 *) pd->port_rcvhdrq +
                        l + dd->ipath_rhf_offset;
                if (dd->ipath_flags & IPATH_NODMA_RTAIL) {
                        u32 seq = ipath_hdrget_seq(rhf_addr);

                        if (++pd->port_seq_cnt > 13)
                                pd->port_seq_cnt = 1;
                        if (seq != pd->port_seq_cnt)
                                last = 1;
                } else if (l == hdrqtail)
                        last = 1;
                /*
                 * update head regs on last packet, and every 16 packets.
                 * Reduce bus traffic, while still trying to prevent
                 * rcvhdrq overflows, for when the queue is nearly full
                 */
                if (last || !(i & 0xf)) {
                        u64 lval = l;

                        /* request IBA6120 and 7220 interrupt only on last */
                        if (last)
                                lval |= dd->ipath_rhdrhead_intr_off;
                        ipath_write_ureg(dd, ur_rcvhdrhead, lval,
                                pd->port_port);
                        if (updegr) {
                                ipath_write_ureg(dd, ur_rcvegrindexhead,
                                                 etail, pd->port_port);
                                updegr = 0;
                        }
                }
        }

        if (!dd->ipath_rhdrhead_intr_off && !reloop &&
            !(dd->ipath_flags & IPATH_NODMA_RTAIL)) {
                /* IBA6110 workaround; we can have a race clearing chip
                 * interrupt with another interrupt about to be delivered,
                 * and can clear it before it is delivered on the GPIO
                 * workaround.  By doing the extra check here for the
                 * in-memory tail register updating while we were doing
                 * earlier packets, we "almost" guarantee we have covered
                 * that case.
                 */
                u32 hqtail = ipath_get_rcvhdrtail(pd);
                if (hqtail != hdrqtail) {
                        hdrqtail = hqtail;
                        reloop = 1; /* loop 1 extra time at most */
                        goto reloop;
                }
        }

        pkttot += i;

        pd->port_head = l;

        if (pkttot > ipath_stats.sps_maxpkts_call)
                ipath_stats.sps_maxpkts_call = pkttot;
        ipath_stats.sps_port0pkts += pkttot;
        ipath_stats.sps_avgpkts_call =
                ipath_stats.sps_port0pkts / ++totcalls;

bail:;
}

/**
 * ipath_update_pio_bufs - update shadow copy of the PIO availability map
 * @dd: the infinipath device
 *
 * called whenever our local copy indicates we have run out of send buffers
 * NOTE: This can be called from interrupt context by some code
 * and from non-interrupt context by ipath_getpiobuf().
 */

static void ipath_update_pio_bufs(struct ipath_devdata *dd)
{
        unsigned long flags;
        int i;
        const unsigned piobregs = (unsigned)dd->ipath_pioavregs;

        /* If the generation (check) bits have changed, then we update the
         * busy bit for the corresponding PIO buffer.  This algorithm will
         * modify positions to the value they already have in some cases
         * (i.e., no change), but it's faster than changing only the bits
         * that have changed.
         *
         * We would like to do this atomicly, to avoid spinlocks in the
         * critical send path, but that's not really possible, given the
         * type of changes, and that this routine could be called on
         * multiple cpu's simultaneously, so we lock in this routine only,
         * to avoid conflicting updates; all we change is the shadow, and
         * it's a single 64 bit memory location, so by definition the update
         * is atomic in terms of what other cpu's can see in testing the
         * bits.  The spin_lock overhead isn't too bad, since it only
         * happens when all buffers are in use, so only cpu overhead, not
         * latency or bandwidth is affected.
         */
        if (!dd->ipath_pioavailregs_dma) {
                ipath_dbg("Update shadow pioavail, but regs_dma NULL!\n");
                return;
        }
        if (ipath_debug & __IPATH_VERBDBG) {
                /* only if packet debug and verbose */
                volatile __le64 *dma = dd->ipath_pioavailregs_dma;
                unsigned long *shadow = dd->ipath_pioavailshadow;

                ipath_cdbg(PKT, "Refill avail, dma0=%llx shad0=%lx, "
                           "d1=%llx s1=%lx, d2=%llx s2=%lx, d3=%llx "
                           "s3=%lx\n",
                           (unsigned long long) le64_to_cpu(dma[0]),
                           shadow[0],
                           (unsigned long long) le64_to_cpu(dma[1]),
                           shadow[1],
                           (unsigned long long) le64_to_cpu(dma[2]),
                           shadow[2],
                           (unsigned long long) le64_to_cpu(dma[3]),
                           shadow[3]);
                if (piobregs > 4)
                        ipath_cdbg(
                                PKT, "2nd group, dma4=%llx shad4=%lx, "
                                "d5=%llx s5=%lx, d6=%llx s6=%lx, "
                                "d7=%llx s7=%lx\n",
                                (unsigned long long) le64_to_cpu(dma[4]),
                                shadow[4],
                                (unsigned long long) le64_to_cpu(dma[5]),
                                shadow[5],
                                (unsigned long long) le64_to_cpu(dma[6]),
                                shadow[6],
                                (unsigned long long) le64_to_cpu(dma[7]),
                                shadow[7]);
        }
        spin_lock_irqsave(&ipath_pioavail_lock, flags);
        for (i = 0; i < piobregs; i++) {
                u64 pchbusy, pchg, piov, pnew;
                /*
                 * Chip Errata: bug 6641; even and odd qwords>3 are swapped
                 */
                if (i > 3 && (dd->ipath_flags & IPATH_SWAP_PIOBUFS))
                        piov = le64_to_cpu(dd->ipath_pioavailregs_dma[i ^ 1]);
                else
                        piov = le64_to_cpu(dd->ipath_pioavailregs_dma[i]);
                pchg = dd->ipath_pioavailkernel[i] &
                        ~(dd->ipath_pioavailshadow[i] ^ piov);
                pchbusy = pchg << INFINIPATH_SENDPIOAVAIL_BUSY_SHIFT;
                if (pchg && (pchbusy & dd->ipath_pioavailshadow[i])) {
                        pnew = dd->ipath_pioavailshadow[i] & ~pchbusy;
                        pnew |= piov & pchbusy;
                        dd->ipath_pioavailshadow[i] = pnew;
                }
        }
        spin_unlock_irqrestore(&ipath_pioavail_lock, flags);
}

/*
 * used to force update of pioavailshadow if we can't get a pio buffer.
 * Needed primarily due to exitting freeze mode after recovering
 * from errors.  Done lazily, because it's safer (known to not
 * be writing pio buffers).
 */
static void ipath_reset_availshadow(struct ipath_devdata *dd)
{
        int i, im;
        unsigned long flags;

        spin_lock_irqsave(&ipath_pioavail_lock, flags);
        for (i = 0; i < dd->ipath_pioavregs; i++) {
                u64 val, oldval;
                /* deal with 6110 chip bug on high register #s */
                im = (i > 3 && (dd->ipath_flags & IPATH_SWAP_PIOBUFS)) ?
                        i ^ 1 : i;
                val = le64_to_cpu(dd->ipath_pioavailregs_dma[im]);
                /*
                 * busy out the buffers not in the kernel avail list,
                 * without changing the generation bits.
                 */
                oldval = dd->ipath_pioavailshadow[i];
                dd->ipath_pioavailshadow[i] = val |
                        ((~dd->ipath_pioavailkernel[i] <<
                        INFINIPATH_SENDPIOAVAIL_BUSY_SHIFT) &
                        0xaaaaaaaaaaaaaaaaULL); /* All BUSY bits in qword */
                if (oldval != dd->ipath_pioavailshadow[i])
                        ipath_dbg("shadow[%d] was %Lx, now %lx\n",
                                i, (unsigned long long) oldval,
                                dd->ipath_pioavailshadow[i]);
        }
        spin_unlock_irqrestore(&ipath_pioavail_lock, flags);
}

/**
 * ipath_setrcvhdrsize - set the receive header size
 * @dd: the infinipath device
 * @rhdrsize: the receive header size
 *
 * called from user init code, and also layered driver init
 */
int ipath_setrcvhdrsize(struct ipath_devdata *dd, unsigned rhdrsize)
{
        int ret = 0;

        if (dd->ipath_flags & IPATH_RCVHDRSZ_SET) {
                if (dd->ipath_rcvhdrsize != rhdrsize) {
                        dev_info(&dd->pcidev->dev,
                                 "Error: can't set protocol header "
                                 "size %u, already %u\n",
                                 rhdrsize, dd->ipath_rcvhdrsize);
                        ret = -EAGAIN;
                } else
                        ipath_cdbg(VERBOSE, "Reuse same protocol header "
                                   "size %u\n", dd->ipath_rcvhdrsize);
        } else if (rhdrsize > (dd->ipath_rcvhdrentsize -
                               (sizeof(u64) / sizeof(u32)))) {
                ipath_dbg("Error: can't set protocol header size %u "
                          "(> max %u)\n", rhdrsize,
                          dd->ipath_rcvhdrentsize -
                          (u32) (sizeof(u64) / sizeof(u32)));
                ret = -EOVERFLOW;
        } else {
                dd->ipath_flags |= IPATH_RCVHDRSZ_SET;
                dd->ipath_rcvhdrsize = rhdrsize;
                ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvhdrsize,
                                 dd->ipath_rcvhdrsize);
                ipath_cdbg(VERBOSE, "Set protocol header size to %u\n",
                           dd->ipath_rcvhdrsize);
        }
        return ret;
}

/*
 * debugging code and stats updates if no pio buffers available.
 */
static noinline void no_pio_bufs(struct ipath_devdata *dd)
{
        unsigned long *shadow = dd->ipath_pioavailshadow;
        __le64 *dma = (__le64 *)dd->ipath_pioavailregs_dma;

        dd->ipath_upd_pio_shadow = 1;

        /*
         * not atomic, but if we lose a stat count in a while, that's OK
         */
        ipath_stats.sps_nopiobufs++;
        if (!(++dd->ipath_consec_nopiobuf % 100000)) {
                ipath_force_pio_avail_update(dd); /* at start */
                ipath_dbg("%u tries no piobufavail ts%lx; dmacopy: "
                        "%llx %llx %llx %llx\n"
                        "ipath  shadow:  %lx %lx %lx %lx\n",
                        dd->ipath_consec_nopiobuf,
                        (unsigned long)get_cycles(),
                        (unsigned long long) le64_to_cpu(dma[0]),
                        (unsigned long long) le64_to_cpu(dma[1]),
                        (unsigned long long) le64_to_cpu(dma[2]),
                        (unsigned long long) le64_to_cpu(dma[3]),
                        shadow[0], shadow[1], shadow[2], shadow[3]);
                /*
                 * 4 buffers per byte, 4 registers above, cover rest
                 * below
                 */
                if ((dd->ipath_piobcnt2k + dd->ipath_piobcnt4k) >
                    (sizeof(shadow[0]) * 4 * 4))
                        ipath_dbg("2nd group: dmacopy: "
                                  "%llx %llx %llx %llx\n"
                                  "ipath  shadow:  %lx %lx %lx %lx\n",
                                  (unsigned long long)le64_to_cpu(dma[4]),
                                  (unsigned long long)le64_to_cpu(dma[5]),
                                  (unsigned long long)le64_to_cpu(dma[6]),
                                  (unsigned long long)le64_to_cpu(dma[7]),
                                  shadow[4], shadow[5], shadow[6], shadow[7]);

                /* at end, so update likely happened */
                ipath_reset_availshadow(dd);
        }
}

/*
 * common code for normal driver pio buffer allocation, and reserved
 * allocation.
 *
 * do appropriate marking as busy, etc.
 * returns buffer number if one found (>=0), negative number is error.
 */
static u32 __iomem *ipath_getpiobuf_range(struct ipath_devdata *dd,
        u32 *pbufnum, u32 first, u32 last, u32 firsti)
{
        int i, j, updated = 0;
        unsigned piobcnt;
        unsigned long flags;
        unsigned long *shadow = dd->ipath_pioavailshadow;
        u32 __iomem *buf;

        piobcnt = last - first;
        if (dd->ipath_upd_pio_shadow) {
                /*
                 * Minor optimization.  If we had no buffers on last call,
                 * start out by doing the update; continue and do scan even
                 * if no buffers were updated, to be paranoid
                 */
                ipath_update_pio_bufs(dd);
                updated++;
                i = first;
        } else
                i = firsti;
rescan:
        /*
         * while test_and_set_bit() is atomic, we do that and then the
         * change_bit(), and the pair is not.  See if this is the cause
         * of the remaining armlaunch errors.
         */
        spin_lock_irqsave(&ipath_pioavail_lock, flags);
        for (j = 0; j < piobcnt; j++, i++) {
                if (i >= last)
                        i = first;
                if (__test_and_set_bit((2 * i) + 1, shadow))
                        continue;
                /* flip generation bit */
                __change_bit(2 * i, shadow);
                break;
        }
        spin_unlock_irqrestore(&ipath_pioavail_lock, flags);

        if (j == piobcnt) {
                if (!updated) {
                        /*
                         * first time through; shadow exhausted, but may be
                         * buffers available, try an update and then rescan.
                         */
                        ipath_update_pio_bufs(dd);
                        updated++;
                        i = first;
                        goto rescan;
                } else if (updated == 1 && piobcnt <=
                        ((dd->ipath_sendctrl
                        >> INFINIPATH_S_UPDTHRESH_SHIFT) &
                        INFINIPATH_S_UPDTHRESH_MASK)) {
                        /*
                         * for chips supporting and using the update
                         * threshold we need to force an update of the
                         * in-memory copy if the count is less than the
                         * thershold, then check one more time.
                         */
                        ipath_force_pio_avail_update(dd);
                        ipath_update_pio_bufs(dd);
                        updated++;
                        i = first;
                        goto rescan;
                }

                no_pio_bufs(dd);
                buf = NULL;
        } else {
                if (i < dd->ipath_piobcnt2k)
                        buf = (u32 __iomem *) (dd->ipath_pio2kbase +
                                               i * dd->ipath_palign);
                else
                        buf = (u32 __iomem *)
                                (dd->ipath_pio4kbase +
                                 (i - dd->ipath_piobcnt2k) * dd->ipath_4kalign);
                if (pbufnum)
                        *pbufnum = i;
        }

        return buf;
}

/**
 * ipath_getpiobuf - find an available pio buffer
 * @dd: the infinipath device
 * @plen: the size of the PIO buffer needed in 32-bit words
 * @pbufnum: the buffer number is placed here
 */
u32 __iomem *ipath_getpiobuf(struct ipath_devdata *dd, u32 plen, u32 *pbufnum)
{
        u32 __iomem *buf;
        u32 pnum, nbufs;
        u32 first, lasti;

        if (plen + 1 >= IPATH_SMALLBUF_DWORDS) {
                first = dd->ipath_piobcnt2k;
                lasti = dd->ipath_lastpioindexl;
        } else {
                first = 0;
                lasti = dd->ipath_lastpioindex;
        }
        nbufs = dd->ipath_piobcnt2k + dd->ipath_piobcnt4k;
        buf = ipath_getpiobuf_range(dd, &pnum, first, nbufs, lasti);

        if (buf) {
                /*
                 * Set next starting place.  It's just an optimization,
                 * it doesn't matter who wins on this, so no locking
                 */
                if (plen + 1 >= IPATH_SMALLBUF_DWORDS)
                        dd->ipath_lastpioindexl = pnum + 1;
                else
                        dd->ipath_lastpioindex = pnum + 1;
                if (dd->ipath_upd_pio_shadow)
                        dd->ipath_upd_pio_shadow = 0;
                if (dd->ipath_consec_nopiobuf)
                        dd->ipath_consec_nopiobuf = 0;
                ipath_cdbg(VERBOSE, "Return piobuf%u %uk @ %p\n",
                           pnum, (pnum < dd->ipath_piobcnt2k) ? 2 : 4, buf);
                if (pbufnum)
                        *pbufnum = pnum;

        }
        return buf;
}

/**
 * ipath_chg_pioavailkernel - change which send buffers are available for kernel
 * @dd: the infinipath device
 * @start: the starting send buffer number
 * @len: the number of send buffers
 * @avail: true if the buffers are available for kernel use, false otherwise
 */
void ipath_chg_pioavailkernel(struct ipath_devdata *dd, unsigned start,
                              unsigned len, int avail)
{
        unsigned long flags;
        unsigned end, cnt = 0;

        /* There are two bits per send buffer (busy and generation) */
        start *= 2;
        end = start + len * 2;

        spin_lock_irqsave(&ipath_pioavail_lock, flags);
        /* Set or clear the busy bit in the shadow. */
        while (start < end) {
                if (avail) {
                        unsigned long dma;
                        int i, im;
                        /*
                         * the BUSY bit will never be set, because we disarm
                         * the user buffers before we hand them back to the
                         * kernel.  We do have to make sure the generation
                         * bit is set correctly in shadow, since it could
                         * have changed many times while allocated to user.
                         * We can't use the bitmap functions on the full
                         * dma array because it is always little-endian, so
                         * we have to flip to host-order first.
                         * BITS_PER_LONG is slightly wrong, since it's
                         * always 64 bits per register in chip...
                         * We only work on 64 bit kernels, so that's OK.
                         */
                        /* deal with 6110 chip bug on high register #s */
                        i = start / BITS_PER_LONG;
                        im = (i > 3 && (dd->ipath_flags & IPATH_SWAP_PIOBUFS)) ?
                                i ^ 1 : i;
                        __clear_bit(INFINIPATH_SENDPIOAVAIL_BUSY_SHIFT
                                + start, dd->ipath_pioavailshadow);
                        dma = (unsigned long) le64_to_cpu(
                                dd->ipath_pioavailregs_dma[im]);
                        if (test_bit((INFINIPATH_SENDPIOAVAIL_CHECK_SHIFT
                                + start) % BITS_PER_LONG, &dma))
                                __set_bit(INFINIPATH_SENDPIOAVAIL_CHECK_SHIFT
                                        + start, dd->ipath_pioavailshadow);
                        else
                                __clear_bit(INFINIPATH_SENDPIOAVAIL_CHECK_SHIFT
                                        + start, dd->ipath_pioavailshadow);
                        __set_bit(start, dd->ipath_pioavailkernel);
                } else {
                        __set_bit(start + INFINIPATH_SENDPIOAVAIL_BUSY_SHIFT,
                                dd->ipath_pioavailshadow);
                        __clear_bit(start, dd->ipath_pioavailkernel);
                }
                start += 2;
        }

        if (dd->ipath_pioupd_thresh) {
                end = 2 * (dd->ipath_piobcnt2k + dd->ipath_piobcnt4k);
                cnt = bitmap_weight(dd->ipath_pioavailkernel, end);
        }
        spin_unlock_irqrestore(&ipath_pioavail_lock, flags);

        /*
         * When moving buffers from kernel to user, if number assigned to
         * the user is less than the pio update threshold, and threshold
         * is supported (cnt was computed > 0), drop the update threshold
         * so we update at least once per allocated number of buffers.
         * In any case, if the kernel buffers are less than the threshold,
         * drop the threshold.  We don't bother increasing it, having once
         * decreased it, since it would typically just cycle back and forth.
         * If we don't decrease below buffers in use, we can wait a long
         * time for an update, until some other context uses PIO buffers.
         */
        if (!avail && len < cnt)
                cnt = len;
        if (cnt < dd->ipath_pioupd_thresh) {
                dd->ipath_pioupd_thresh = cnt;
                ipath_dbg("Decreased pio update threshold to %u\n",
                        dd->ipath_pioupd_thresh);
                spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
                dd->ipath_sendctrl &= ~(INFINIPATH_S_UPDTHRESH_MASK
                        << INFINIPATH_S_UPDTHRESH_SHIFT);
                dd->ipath_sendctrl |= dd->ipath_pioupd_thresh
                        << INFINIPATH_S_UPDTHRESH_SHIFT;
                ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
                        dd->ipath_sendctrl);
                spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
        }
}

/**
 * ipath_create_rcvhdrq - create a receive header queue
 * @dd: the infinipath device
 * @pd: the port data
 *
 * this must be contiguous memory (from an i/o perspective), and must be
 * DMA'able (which means for some systems, it will go through an IOMMU,
 * or be forced into a low address range).
 */
int ipath_create_rcvhdrq(struct ipath_devdata *dd,
                         struct ipath_portdata *pd)
{
        int ret = 0;

        if (!pd->port_rcvhdrq) {
                dma_addr_t phys_hdrqtail;
                gfp_t gfp_flags = GFP_USER | __GFP_COMP;
                int amt = ALIGN(dd->ipath_rcvhdrcnt * dd->ipath_rcvhdrentsize *
                                sizeof(u32), PAGE_SIZE);

                pd->port_rcvhdrq = dma_alloc_coherent(
                        &dd->pcidev->dev, amt, &pd->port_rcvhdrq_phys,
                        gfp_flags);

                if (!pd->port_rcvhdrq) {
                        ipath_dev_err(dd, "attempt to allocate %d bytes "
                                      "for port %u rcvhdrq failed\n",
                                      amt, pd->port_port);
                        ret = -ENOMEM;
                        goto bail;
                }

                if (!(dd->ipath_flags & IPATH_NODMA_RTAIL)) {
                        pd->port_rcvhdrtail_kvaddr = dma_alloc_coherent(
                                &dd->pcidev->dev, PAGE_SIZE, &phys_hdrqtail,
                                GFP_KERNEL);
                        if (!pd->port_rcvhdrtail_kvaddr) {
                                ipath_dev_err(dd, "attempt to allocate 1 page "
                                        "for port %u rcvhdrqtailaddr "
                                        "failed\n", pd->port_port);
                                ret = -ENOMEM;
                                dma_free_coherent(&dd->pcidev->dev, amt,
                                        pd->port_rcvhdrq,
                                        pd->port_rcvhdrq_phys);
                                pd->port_rcvhdrq = NULL;
                                goto bail;
                        }
                        pd->port_rcvhdrqtailaddr_phys = phys_hdrqtail;
                        ipath_cdbg(VERBOSE, "port %d hdrtailaddr, %llx "
                                   "physical\n", pd->port_port,
                                   (unsigned long long) phys_hdrqtail);
                }

                pd->port_rcvhdrq_size = amt;

                ipath_cdbg(VERBOSE, "%d pages at %p (phys %lx) size=%lu "
                           "for port %u rcvhdr Q\n",
                           amt >> PAGE_SHIFT, pd->port_rcvhdrq,
                           (unsigned long) pd->port_rcvhdrq_phys,
                           (unsigned long) pd->port_rcvhdrq_size,
                           pd->port_port);
        }
        else
                ipath_cdbg(VERBOSE, "reuse port %d rcvhdrq @%p %llx phys; "
                           "hdrtailaddr@%p %llx physical\n",
                           pd->port_port, pd->port_rcvhdrq,
                           (unsigned long long) pd->port_rcvhdrq_phys,
                           pd->port_rcvhdrtail_kvaddr, (unsigned long long)
                           pd->port_rcvhdrqtailaddr_phys);

        /* clear for security and sanity on each use */
        memset(pd->port_rcvhdrq, 0, pd->port_rcvhdrq_size);
        if (pd->port_rcvhdrtail_kvaddr)
                memset(pd->port_rcvhdrtail_kvaddr, 0, PAGE_SIZE);

        /*
         * tell chip each time we init it, even if we are re-using previous
         * memory (we zero the register at process close)
         */
        ipath_write_kreg_port(dd, dd->ipath_kregs->kr_rcvhdrtailaddr,
                              pd->port_port, pd->port_rcvhdrqtailaddr_phys);
        ipath_write_kreg_port(dd, dd->ipath_kregs->kr_rcvhdraddr,
                              pd->port_port, pd->port_rcvhdrq_phys);

bail:
        return ret;
}


/*
 * Flush all sends that might be in the ready to send state, as well as any
 * that are in the process of being sent.   Used whenever we need to be
 * sure the send side is idle.  Cleans up all buffer state by canceling
 * all pio buffers, and issuing an abort, which cleans up anything in the
 * launch fifo.  The cancel is superfluous on some chip versions, but
 * it's safer to always do it.
 * PIOAvail bits are updated by the chip as if normal send had happened.
 */
void ipath_cancel_sends(struct ipath_devdata *dd, int restore_sendctrl)
{
        unsigned long flags;

        if (dd->ipath_flags & IPATH_IB_AUTONEG_INPROG) {
                ipath_cdbg(VERBOSE, "Ignore while in autonegotiation\n");
                goto bail;
        }
        /*
         * If we have SDMA, and it's not disabled, we have to kick off the
         * abort state machine, provided we aren't already aborting.
         * If we are in the process of aborting SDMA (!DISABLED, but ABORTING),
         * we skip the rest of this routine. It is already "in progress"
         */
        if (dd->ipath_flags & IPATH_HAS_SEND_DMA) {
                int skip_cancel;
                unsigned long *statp = &dd->ipath_sdma_status;

                spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
                skip_cancel =
                        test_and_set_bit(IPATH_SDMA_ABORTING, statp)
                        && !test_bit(IPATH_SDMA_DISABLED, statp);
                spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
                if (skip_cancel)
                        goto bail;
        }

        ipath_dbg("Cancelling all in-progress send buffers\n");

        /* skip armlaunch errs for a while */
        dd->ipath_lastcancel = jiffies + HZ / 2;

        /*
         * The abort bit is auto-clearing.  We also don't want pioavail
         * update happening during this, and we don't want any other
         * sends going out, so turn those off for the duration.  We read
         * the scratch register to be sure that cancels and the abort
         * have taken effect in the chip.  Otherwise two parts are same
         * as ipath_force_pio_avail_update()
         */
        spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
        dd->ipath_sendctrl &= ~(INFINIPATH_S_PIOBUFAVAILUPD
                | INFINIPATH_S_PIOENABLE);
        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
                dd->ipath_sendctrl | INFINIPATH_S_ABORT);
        ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
        spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);

        /* disarm all send buffers */
        ipath_disarm_piobufs(dd, 0,
                dd->ipath_piobcnt2k + dd->ipath_piobcnt4k);

        if (dd->ipath_flags & IPATH_HAS_SEND_DMA)
                set_bit(IPATH_SDMA_DISARMED, &dd->ipath_sdma_status);

        if (restore_sendctrl) {
                /* else done by caller later if needed */
                spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
                dd->ipath_sendctrl |= INFINIPATH_S_PIOBUFAVAILUPD |
                        INFINIPATH_S_PIOENABLE;
                ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
                        dd->ipath_sendctrl);
                /* and again, be sure all have hit the chip */
                ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
                spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
        }

        if ((dd->ipath_flags & IPATH_HAS_SEND_DMA) &&
            !test_bit(IPATH_SDMA_DISABLED, &dd->ipath_sdma_status) &&
            test_bit(IPATH_SDMA_RUNNING, &dd->ipath_sdma_status)) {
                spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
                /* only wait so long for intr */
                dd->ipath_sdma_abort_intr_timeout = jiffies + HZ;
                dd->ipath_sdma_reset_wait = 200;
                if (!test_bit(IPATH_SDMA_SHUTDOWN, &dd->ipath_sdma_status))
                        tasklet_hi_schedule(&dd->ipath_sdma_abort_task);
                spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
        }
bail:;
}

/*
 * Force an update of in-memory copy of the pioavail registers, when
 * needed for any of a variety of reasons.  We read the scratch register
 * to make it highly likely that the update will have happened by the
 * time we return.  If already off (as in cancel_sends above), this
 * routine is a nop, on the assumption that the caller will "do the
 * right thing".
 */
void ipath_force_pio_avail_update(struct ipath_devdata *dd)
{
        unsigned long flags;

        spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
        if (dd->ipath_sendctrl & INFINIPATH_S_PIOBUFAVAILUPD) {
                ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
                        dd->ipath_sendctrl & ~INFINIPATH_S_PIOBUFAVAILUPD);
                ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
                ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl,
                        dd->ipath_sendctrl);
                ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
        }
        spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);
}

static void ipath_set_ib_lstate(struct ipath_devdata *dd, int linkcmd,
                                int linitcmd)
{
        u64 mod_wd;
        static const char *what[4] = {
                [0] = "NOP",
                [INFINIPATH_IBCC_LINKCMD_DOWN] = "DOWN",
                [INFINIPATH_IBCC_LINKCMD_ARMED] = "ARMED",
                [INFINIPATH_IBCC_LINKCMD_ACTIVE] = "ACTIVE"
        };

        if (linitcmd == INFINIPATH_IBCC_LINKINITCMD_DISABLE) {
                /*
                 * If we are told to disable, note that so link-recovery
                 * code does not attempt to bring us back up.
                 */
                preempt_disable();
                dd->ipath_flags |= IPATH_IB_LINK_DISABLED;
                preempt_enable();
        } else if (linitcmd) {
                /*
                 * Any other linkinitcmd will lead to LINKDOWN and then
                 * to INIT (if all is well), so clear flag to let
                 * link-recovery code attempt to bring us back up.
                 */
                preempt_disable();
                dd->ipath_flags &= ~IPATH_IB_LINK_DISABLED;
                preempt_enable();
        }

        mod_wd = (linkcmd << dd->ibcc_lc_shift) |
                (linitcmd << INFINIPATH_IBCC_LINKINITCMD_SHIFT);
        ipath_cdbg(VERBOSE,
                "Moving unit %u to %s (initcmd=0x%x), current ltstate is %s\n",

                dd->ipath_unit, what[linkcmd], linitcmd,
                ipath_ibcstatus_str[ipath_ib_linktrstate(dd,
                        ipath_read_kreg64(dd, dd->ipath_kregs->kr_ibcstatus))]);

        ipath_write_kreg(dd, dd->ipath_kregs->kr_ibcctrl,
                         dd->ipath_ibcctrl | mod_wd);
        /* read from chip so write is flushed */
        (void) ipath_read_kreg64(dd, dd->ipath_kregs->kr_ibcstatus);
}

int ipath_set_linkstate(struct ipath_devdata *dd, u8 newstate)
{
        u32 lstate;
        int ret;

        switch (newstate) {
        case IPATH_IB_LINKDOWN_ONLY:
                ipath_set_ib_lstate(dd, INFINIPATH_IBCC_LINKCMD_DOWN, 0);
                /* don't wait */
                ret = 0;
                goto bail;

        case IPATH_IB_LINKDOWN:
                ipath_set_ib_lstate(dd, INFINIPATH_IBCC_LINKCMD_DOWN,
                                        INFINIPATH_IBCC_LINKINITCMD_POLL);
                /* don't wait */
                ret = 0;
                goto bail;

        case IPATH_IB_LINKDOWN_SLEEP:
                ipath_set_ib_lstate(dd, INFINIPATH_IBCC_LINKCMD_DOWN,
                                        INFINIPATH_IBCC_LINKINITCMD_SLEEP);
                /* don't wait */
                ret = 0;
                goto bail;

        case IPATH_IB_LINKDOWN_DISABLE:
                ipath_set_ib_lstate(dd, INFINIPATH_IBCC_LINKCMD_DOWN,
                                        INFINIPATH_IBCC_LINKINITCMD_DISABLE);
                /* don't wait */
                ret = 0;
                goto bail;

        case IPATH_IB_LINKARM:
                if (dd->ipath_flags & IPATH_LINKARMED) {
                        ret = 0;
                        goto bail;
                }
                if (!(dd->ipath_flags &
                      (IPATH_LINKINIT | IPATH_LINKACTIVE))) {
                        ret = -EINVAL;
                        goto bail;
                }
                ipath_set_ib_lstate(dd, INFINIPATH_IBCC_LINKCMD_ARMED, 0);

                /*
                 * Since the port can transition to ACTIVE by receiving
                 * a non VL 15 packet, wait for either state.
                 */
                lstate = IPATH_LINKARMED | IPATH_LINKACTIVE;
                break;

        case IPATH_IB_LINKACTIVE:
                if (dd->ipath_flags & IPATH_LINKACTIVE) {
                        ret = 0;
                        goto bail;
                }
                if (!(dd->ipath_flags & IPATH_LINKARMED)) {
                        ret = -EINVAL;
                        goto bail;
                }
                ipath_set_ib_lstate(dd, INFINIPATH_IBCC_LINKCMD_ACTIVE, 0);
                lstate = IPATH_LINKACTIVE;
                break;

        case IPATH_IB_LINK_LOOPBACK:
                dev_info(&dd->pcidev->dev, "Enabling IB local loopback\n");
                dd->ipath_ibcctrl |= INFINIPATH_IBCC_LOOPBACK;
                ipath_write_kreg(dd, dd->ipath_kregs->kr_ibcctrl,
                                 dd->ipath_ibcctrl);

                /* turn heartbeat off, as it causes loopback to fail */
                dd->ipath_f_set_ib_cfg(dd, IPATH_IB_CFG_HRTBT,
                                       IPATH_IB_HRTBT_OFF);
                /* don't wait */
                ret = 0;
                goto bail;

        case IPATH_IB_LINK_EXTERNAL:
                dev_info(&dd->pcidev->dev,
                        "Disabling IB local loopback (normal)\n");
                dd->ipath_f_set_ib_cfg(dd, IPATH_IB_CFG_HRTBT,
                                       IPATH_IB_HRTBT_ON);
                dd->ipath_ibcctrl &= ~INFINIPATH_IBCC_LOOPBACK;
                ipath_write_kreg(dd, dd->ipath_kregs->kr_ibcctrl,
                                 dd->ipath_ibcctrl);
                /* don't wait */
                ret = 0;
                goto bail;

        /*
         * Heartbeat can be explicitly enabled by the user via
         * "hrtbt_enable" "file", and if disabled, trying to enable here
         * will have no effect.  Implicit changes (heartbeat off when
         * loopback on, and vice versa) are included to ease testing.
         */
        case IPATH_IB_LINK_HRTBT:
                ret = dd->ipath_f_set_ib_cfg(dd, IPATH_IB_CFG_HRTBT,
                        IPATH_IB_HRTBT_ON);
                goto bail;

        case IPATH_IB_LINK_NO_HRTBT:
                ret = dd->ipath_f_set_ib_cfg(dd, IPATH_IB_CFG_HRTBT,
                        IPATH_IB_HRTBT_OFF);
                goto bail;

        default:
                ipath_dbg("Invalid linkstate 0x%x requested\n", newstate);
                ret = -EINVAL;
                goto bail;
        }
        ret = ipath_wait_linkstate(dd, lstate, 2000);

bail:
        return ret;
}

/**
 * ipath_set_mtu - set the MTU
 * @dd: the infinipath device
 * @arg: the new MTU
 *
 * we can handle "any" incoming size, the issue here is whether we
 * need to restrict our outgoing size.   For now, we don't do any
 * sanity checking on this, and we don't deal with what happens to
 * programs that are already running when the size changes.
 * NOTE: changing the MTU will usually cause the IBC to go back to
 * link INIT state...
 */
int ipath_set_mtu(struct ipath_devdata *dd, u16 arg)
{
        u32 piosize;
        int changed = 0;
        int ret;

        /*
         * mtu is IB data payload max.  It's the largest power of 2 less
         * than piosize (or even larger, since it only really controls the
         * largest we can receive; we can send the max of the mtu and
         * piosize).  We check that it's one of the valid IB sizes.
         */
        if (arg != 256 && arg != 512 && arg != 1024 && arg != 2048 &&
            (arg != 4096 || !ipath_mtu4096)) {
                ipath_dbg("Trying to set invalid mtu %u, failing\n", arg);
                ret = -EINVAL;
                goto bail;
        }
        if (dd->ipath_ibmtu == arg) {
                ret = 0;        /* same as current */
                goto bail;
        }

        piosize = dd->ipath_ibmaxlen;
        dd->ipath_ibmtu = arg;

        if (arg >= (piosize - IPATH_PIO_MAXIBHDR)) {
                /* Only if it's not the initial value (or reset to it) */
                if (piosize != dd->ipath_init_ibmaxlen) {
                        if (arg > piosize && arg <= dd->ipath_init_ibmaxlen)
                                piosize = dd->ipath_init_ibmaxlen;
                        dd->ipath_ibmaxlen = piosize;
                        changed = 1;
                }
        } else if ((arg + IPATH_PIO_MAXIBHDR) != dd->ipath_ibmaxlen) {
                piosize = arg + IPATH_PIO_MAXIBHDR;
                ipath_cdbg(VERBOSE, "ibmaxlen was 0x%x, setting to 0x%x "
                           "(mtu 0x%x)\n", dd->ipath_ibmaxlen, piosize,
                           arg);
                dd->ipath_ibmaxlen = piosize;
                changed = 1;
        }

        if (changed) {
                u64 ibc = dd->ipath_ibcctrl, ibdw;
                /*
                 * update our housekeeping variables, and set IBC max
                 * size, same as init code; max IBC is max we allow in
                 * buffer, less the qword pbc, plus 1 for ICRC, in dwords
                 */
                dd->ipath_ibmaxlen = piosize - 2 * sizeof(u32);
                ibdw = (dd->ipath_ibmaxlen >> 2) + 1;
                ibc &= ~(INFINIPATH_IBCC_MAXPKTLEN_MASK <<
                         dd->ibcc_mpl_shift);
                ibc |= ibdw << dd->ibcc_mpl_shift;
                dd->ipath_ibcctrl = ibc;
                ipath_write_kreg(dd, dd->ipath_kregs->kr_ibcctrl,
                                 dd->ipath_ibcctrl);
                dd->ipath_f_tidtemplate(dd);
        }

        ret = 0;

bail:
        return ret;
}

int ipath_set_lid(struct ipath_devdata *dd, u32 lid, u8 lmc)
{
        dd->ipath_lid = lid;
        dd->ipath_lmc = lmc;

        dd->ipath_f_set_ib_cfg(dd, IPATH_IB_CFG_LIDLMC, lid |
                (~((1U << lmc) - 1)) << 16);

        dev_info(&dd->pcidev->dev, "We got a lid: 0x%x\n", lid);

        return 0;
}


/**
 * ipath_write_kreg_port - write a device's per-port 64-bit kernel register
 * @dd: the infinipath device
 * @regno: the register number to write
 * @port: the port containing the register
 * @value: the value to write
 *
 * Registers that vary with the chip implementation constants (port)
 * use this routine.
 */
void ipath_write_kreg_port(const struct ipath_devdata *dd, ipath_kreg regno,
                          unsigned port, u64 value)
{
        u16 where;

        if (port < dd->ipath_portcnt &&
            (regno == dd->ipath_kregs->kr_rcvhdraddr ||
             regno == dd->ipath_kregs->kr_rcvhdrtailaddr))
                where = regno + port;
        else
                where = -1;

        ipath_write_kreg(dd, where, value);
}

/*
 * Following deal with the "obviously simple" task of overriding the state
 * of the LEDS, which normally indicate link physical and logical status.
 * The complications arise in dealing with different hardware mappings
 * and the board-dependent routine being called from interrupts.
 * and then there's the requirement to _flash_ them.
 */
#define LED_OVER_FREQ_SHIFT 8
#define LED_OVER_FREQ_MASK (0xFF<<LED_OVER_FREQ_SHIFT)
/* Below is "non-zero" to force override, but both actual LEDs are off */
#define LED_OVER_BOTH_OFF (8)

static void ipath_run_led_override(unsigned long opaque)
{
        struct ipath_devdata *dd = (struct ipath_devdata *)opaque;
        int timeoff;
        int pidx;
        u64 lstate, ltstate, val;

        if (!(dd->ipath_flags & IPATH_INITTED))
                return;

        pidx = dd->ipath_led_override_phase++ & 1;
        dd->ipath_led_override = dd->ipath_led_override_vals[pidx];
        timeoff = dd->ipath_led_override_timeoff;

        /*
         * below potentially restores the LED values per current status,
         * should also possibly setup the traffic-blink register,
         * but leave that to per-chip functions.
         */
        val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_ibcstatus);
        ltstate = ipath_ib_linktrstate(dd, val);
        lstate = ipath_ib_linkstate(dd, val);

        dd->ipath_f_setextled(dd, lstate, ltstate);
        mod_timer(&dd->ipath_led_override_timer, jiffies + timeoff);
}

void ipath_set_led_override(struct ipath_devdata *dd, unsigned int val)
{
        int timeoff, freq;

        if (!(dd->ipath_flags & IPATH_INITTED))
                return;

        /* First check if we are blinking. If not, use 1HZ polling */
        timeoff = HZ;
        freq = (val & LED_OVER_FREQ_MASK) >> LED_OVER_FREQ_SHIFT;

        if (freq) {
                /* For blink, set each phase from one nybble of val */
                dd->ipath_led_override_vals[0] = val & 0xF;
                dd->ipath_led_override_vals[1] = (val >> 4) & 0xF;
                timeoff = (HZ << 4)/freq;
        } else {
                /* Non-blink set both phases the same. */
                dd->ipath_led_override_vals[0] = val & 0xF;
                dd->ipath_led_override_vals[1] = val & 0xF;
        }
        dd->ipath_led_override_timeoff = timeoff;

        /*
         * If the timer has not already been started, do so. Use a "quick"
         * timeout so the function will be called soon, to look at our request.
         */
        if (atomic_inc_return(&dd->ipath_led_override_timer_active) == 1) {
                /* Need to start timer */
                init_timer(&dd->ipath_led_override_timer);
                dd->ipath_led_override_timer.function =
                                                 ipath_run_led_override;
                dd->ipath_led_override_timer.data = (unsigned long) dd;
                dd->ipath_led_override_timer.expires = jiffies + 1;
                add_timer(&dd->ipath_led_override_timer);
        } else
                atomic_dec(&dd->ipath_led_override_timer_active);
}

/**
 * ipath_shutdown_device - shut down a device
 * @dd: the infinipath device
 *
 * This is called to make the device quiet when we are about to
 * unload the driver, and also when the device is administratively
 * disabled.   It does not free any data structures.
 * Everything it does has to be setup again by ipath_init_chip(dd,1)
 */
void ipath_shutdown_device(struct ipath_devdata *dd)
{
        unsigned long flags;

        ipath_dbg("Shutting down the device\n");

        ipath_hol_up(dd); /* make sure user processes aren't suspended */

        dd->ipath_flags |= IPATH_LINKUNK;
        dd->ipath_flags &= ~(IPATH_INITTED | IPATH_LINKDOWN |
                             IPATH_LINKINIT | IPATH_LINKARMED |
                             IPATH_LINKACTIVE);
        *dd->ipath_statusp &= ~(IPATH_STATUS_IB_CONF |
                                IPATH_STATUS_IB_READY);

        /* mask interrupts, but not errors */
        ipath_write_kreg(dd, dd->ipath_kregs->kr_intmask, 0ULL);

        dd->ipath_rcvctrl = 0;
        ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
                         dd->ipath_rcvctrl);

        if (dd->ipath_flags & IPATH_HAS_SEND_DMA)
                teardown_sdma(dd);

        /*
         * gracefully stop all sends allowing any in progress to trickle out
         * first.
         */
        spin_lock_irqsave(&dd->ipath_sendctrl_lock, flags);
        dd->ipath_sendctrl = 0;
        ipath_write_kreg(dd, dd->ipath_kregs->kr_sendctrl, dd->ipath_sendctrl);
        /* flush it */
        ipath_read_kreg64(dd, dd->ipath_kregs->kr_scratch);
        spin_unlock_irqrestore(&dd->ipath_sendctrl_lock, flags);

        /*
         * enough for anything that's going to trickle out to have actually
         * done so.
         */
        udelay(5);

        dd->ipath_f_setextled(dd, 0, 0); /* make sure LEDs are off */

        ipath_set_ib_lstate(dd, 0, INFINIPATH_IBCC_LINKINITCMD_DISABLE);
        ipath_cancel_sends(dd, 0);

        /*
         * we are shutting down, so tell components that care.  We don't do
         * this on just a link state change, much like ethernet, a cable
         * unplug, etc. doesn't change driver state
         */
        signal_ib_event(dd, IB_EVENT_PORT_ERR);

        /* disable IBC */
        dd->ipath_control &= ~INFINIPATH_C_LINKENABLE;
        ipath_write_kreg(dd, dd->ipath_kregs->kr_control,
                         dd->ipath_control | INFINIPATH_C_FREEZEMODE);

        /*
         * clear SerdesEnable and turn the leds off; do this here because
         * we are unloading, so don't count on interrupts to move along
         * Turn the LEDs off explicitly for the same reason.
         */
        dd->ipath_f_quiet_serdes(dd);

        /* stop all the timers that might still be running */
        del_timer_sync(&dd->ipath_hol_timer);
        if (dd->ipath_stats_timer_active) {
                del_timer_sync(&dd->ipath_stats_timer);
                dd->ipath_stats_timer_active = 0;
        }
        if (dd->ipath_intrchk_timer.data) {
                del_timer_sync(&dd->ipath_intrchk_timer);
                dd->ipath_intrchk_timer.data = 0;
        }
        if (atomic_read(&dd->ipath_led_override_timer_active)) {
                del_timer_sync(&dd->ipath_led_override_timer);
                atomic_set(&dd->ipath_led_override_timer_active, 0);
        }

        /*
         * clear all interrupts and errors, so that the next time the driver
         * is loaded or device is enabled, we know that whatever is set
         * happened while we were unloaded
         */
        ipath_write_kreg(dd, dd->ipath_kregs->kr_hwerrclear,
                         ~0ULL & ~INFINIPATH_HWE_MEMBISTFAILED);
        ipath_write_kreg(dd, dd->ipath_kregs->kr_errorclear, -1LL);
        ipath_write_kreg(dd, dd->ipath_kregs->kr_intclear, -1LL);

        ipath_cdbg(VERBOSE, "Flush time and errors to EEPROM\n");
        ipath_update_eeprom_log(dd);
}

/**
 * ipath_free_pddata - free a port's allocated data
 * @dd: the infinipath device
 * @pd: the portdata structure
 *
 * free up any allocated data for a port
 * This should not touch anything that would affect a simultaneous
 * re-allocation of port data, because it is called after ipath_mutex
 * is released (and can be called from reinit as well).
 * It should never change any chip state, or global driver state.
 * (The only exception to global state is freeing the port0 port0_skbs.)
 */
void ipath_free_pddata(struct ipath_devdata *dd, struct ipath_portdata *pd)
{
        if (!pd)
                return;

        if (pd->port_rcvhdrq) {
                ipath_cdbg(VERBOSE, "free closed port %d rcvhdrq @ %p "
                           "(size=%lu)\n", pd->port_port, pd->port_rcvhdrq,
                           (unsigned long) pd->port_rcvhdrq_size);
                dma_free_coherent(&dd->pcidev->dev, pd->port_rcvhdrq_size,
                                  pd->port_rcvhdrq, pd->port_rcvhdrq_phys);
                pd->port_rcvhdrq = NULL;
                if (pd->port_rcvhdrtail_kvaddr) {
                        dma_free_coherent(&dd->pcidev->dev, PAGE_SIZE,
                                         pd->port_rcvhdrtail_kvaddr,
                                         pd->port_rcvhdrqtailaddr_phys);
                        pd->port_rcvhdrtail_kvaddr = NULL;
                }
        }
        if (pd->port_port && pd->port_rcvegrbuf) {
                unsigned e;

                for (e = 0; e < pd->port_rcvegrbuf_chunks; e++) {
                        void *base = pd->port_rcvegrbuf[e];
                        size_t size = pd->port_rcvegrbuf_size;

                        ipath_cdbg(VERBOSE, "egrbuf free(%p, %lu), "
                                   "chunk %u/%u\n", base,
                                   (unsigned long) size,
                                   e, pd->port_rcvegrbuf_chunks);
                        dma_free_coherent(&dd->pcidev->dev, size,
                                base, pd->port_rcvegrbuf_phys[e]);
                }
                kfree(pd->port_rcvegrbuf);
                pd->port_rcvegrbuf = NULL;
                kfree(pd->port_rcvegrbuf_phys);
                pd->port_rcvegrbuf_phys = NULL;
                pd->port_rcvegrbuf_chunks = 0;
        } else if (pd->port_port == 0 && dd->ipath_port0_skbinfo) {
                unsigned e;
                struct ipath_skbinfo *skbinfo = dd->ipath_port0_skbinfo;

                dd->ipath_port0_skbinfo = NULL;
                ipath_cdbg(VERBOSE, "free closed port %d "
                           "ipath_port0_skbinfo @ %p\n", pd->port_port,
                           skbinfo);
                for (e = 0; e < dd->ipath_p0_rcvegrcnt; e++)
                        if (skbinfo[e].skb) {
                                pci_unmap_single(dd->pcidev, skbinfo[e].phys,
                                                 dd->ipath_ibmaxlen,
                                                 PCI_DMA_FROMDEVICE);
                                dev_kfree_skb(skbinfo[e].skb);
                        }
                vfree(skbinfo);
        }
        kfree(pd->port_tid_pg_list);
        vfree(pd->subport_uregbase);
        vfree(pd->subport_rcvegrbuf);
        vfree(pd->subport_rcvhdr_base);
        kfree(pd);
}

static int __init infinipath_init(void)
{
        int ret;

        if (ipath_debug & __IPATH_DBG)
                printk(KERN_INFO DRIVER_LOAD_MSG "%s", ib_ipath_version);

        /*
         * These must be called before the driver is registered with
         * the PCI subsystem.
         */
        idr_init(&unit_table);
        if (!idr_pre_get(&unit_table, GFP_KERNEL)) {
                printk(KERN_ERR IPATH_DRV_NAME ": idr_pre_get() failed\n");
                ret = -ENOMEM;
                goto bail;
        }

        ret = pci_register_driver(&ipath_driver);
        if (ret < 0) {
                printk(KERN_ERR IPATH_DRV_NAME
                       ": Unable to register driver: error %d\n", -ret);
                goto bail_unit;
        }

        ret = ipath_init_ipathfs();
        if (ret < 0) {
                printk(KERN_ERR IPATH_DRV_NAME ": Unable to create "
                       "ipathfs: error %d\n", -ret);
                goto bail_pci;
        }

        goto bail;

bail_pci:
        pci_unregister_driver(&ipath_driver);

bail_unit:
        idr_destroy(&unit_table);

bail:
        return ret;
}

static void __exit infinipath_cleanup(void)
{
        ipath_exit_ipathfs();

        ipath_cdbg(VERBOSE, "Unregistering pci driver\n");
        pci_unregister_driver(&ipath_driver);

        idr_destroy(&unit_table);
}

/**
 * ipath_reset_device - reset the chip if possible
 * @unit: the device to reset
 *
 * Whether or not reset is successful, we attempt to re-initialize the chip
 * (that is, much like a driver unload/reload).  We clear the INITTED flag
 * so that the various entry points will fail until we reinitialize.  For
 * now, we only allow this if no user ports are open that use chip resources
 */
int ipath_reset_device(int unit)
{
        int ret, i;
        struct ipath_devdata *dd = ipath_lookup(unit);
        unsigned long flags;

        if (!dd) {
                ret = -ENODEV;
                goto bail;
        }

        if (atomic_read(&dd->ipath_led_override_timer_active)) {
                /* Need to stop LED timer, _then_ shut off LEDs */
                del_timer_sync(&dd->ipath_led_override_timer);
                atomic_set(&dd->ipath_led_override_timer_active, 0);
        }

        /* Shut off LEDs after we are sure timer is not running */
        dd->ipath_led_override = LED_OVER_BOTH_OFF;
        dd->ipath_f_setextled(dd, 0, 0);

        dev_info(&dd->pcidev->dev, "Reset on unit %u requested\n", unit);

        if (!dd->ipath_kregbase || !(dd->ipath_flags & IPATH_PRESENT)) {
                dev_info(&dd->pcidev->dev, "Invalid unit number %u or "
                         "not initialized or not present\n", unit);
                ret = -ENXIO;
                goto bail;
        }

        spin_lock_irqsave(&dd->ipath_uctxt_lock, flags);
        if (dd->ipath_pd)
                for (i = 1; i < dd->ipath_cfgports; i++) {
                        if (!dd->ipath_pd[i] || !dd->ipath_pd[i]->port_cnt)
                                continue;
                        spin_unlock_irqrestore(&dd->ipath_uctxt_lock, flags);
                        ipath_dbg("unit %u port %d is in use "
                                  "(PID %u cmd %s), can't reset\n",
                                  unit, i,
                                  pid_nr(dd->ipath_pd[i]->port_pid),
                                  dd->ipath_pd[i]->port_comm);
                        ret = -EBUSY;
                        goto bail;
                }
        spin_unlock_irqrestore(&dd->ipath_uctxt_lock, flags);

        if (dd->ipath_flags & IPATH_HAS_SEND_DMA)
                teardown_sdma(dd);

        dd->ipath_flags &= ~IPATH_INITTED;
        ipath_write_kreg(dd, dd->ipath_kregs->kr_intmask, 0ULL);
        ret = dd->ipath_f_reset(dd);
        if (ret == 1) {
                ipath_dbg("Reinitializing unit %u after reset attempt\n",
                          unit);
                ret = ipath_init_chip(dd, 1);
        } else
                ret = -EAGAIN;
        if (ret)
                ipath_dev_err(dd, "Reinitialize unit %u after "
                              "reset failed with %d\n", unit, ret);
        else
                dev_info(&dd->pcidev->dev, "Reinitialized unit %u after "
                         "resetting\n", unit);

bail:
        return ret;
}

/*
 * send a signal to all the processes that have the driver open
 * through the normal interfaces (i.e., everything other than diags
 * interface).  Returns number of signalled processes.
 */
static int ipath_signal_procs(struct ipath_devdata *dd, int sig)
{
        int i, sub, any = 0;
        struct pid *pid;
        unsigned long flags;

        if (!dd->ipath_pd)
                return 0;

        spin_lock_irqsave(&dd->ipath_uctxt_lock, flags);
        for (i = 1; i < dd->ipath_cfgports; i++) {
                if (!dd->ipath_pd[i] || !dd->ipath_pd[i]->port_cnt)
                        continue;
                pid = dd->ipath_pd[i]->port_pid;
                if (!pid)
                        continue;

                dev_info(&dd->pcidev->dev, "context %d in use "
                          "(PID %u), sending signal %d\n",
                          i, pid_nr(pid), sig);
                kill_pid(pid, sig, 1);
                any++;
                for (sub = 0; sub < INFINIPATH_MAX_SUBPORT; sub++) {
                        pid = dd->ipath_pd[i]->port_subpid[sub];
                        if (!pid)
                                continue;
                        dev_info(&dd->pcidev->dev, "sub-context "
                                "%d:%d in use (PID %u), sending "
                                "signal %d\n", i, sub, pid_nr(pid), sig);
                        kill_pid(pid, sig, 1);
                        any++;
                }
        }
        spin_unlock_irqrestore(&dd->ipath_uctxt_lock, flags);
        return any;
}

static void ipath_hol_signal_down(struct ipath_devdata *dd)
{
        if (ipath_signal_procs(dd, SIGSTOP))
                ipath_dbg("Stopped some processes\n");
        ipath_cancel_sends(dd, 1);
}


static void ipath_hol_signal_up(struct ipath_devdata *dd)
{
        if (ipath_signal_procs(dd, SIGCONT))
                ipath_dbg("Continued some processes\n");
}

/*
 * link is down, stop any users processes, and flush pending sends
 * to prevent HoL blocking, then start the HoL timer that
 * periodically continues, then stop procs, so they can detect
 * link down if they want, and do something about it.
 * Timer may already be running, so use mod_timer, not add_timer.
 */
void ipath_hol_down(struct ipath_devdata *dd)
{
        dd->ipath_hol_state = IPATH_HOL_DOWN;
        ipath_hol_signal_down(dd);
        dd->ipath_hol_next = IPATH_HOL_DOWNCONT;
        dd->ipath_hol_timer.expires = jiffies +
                msecs_to_jiffies(ipath_hol_timeout_ms);
        mod_timer(&dd->ipath_hol_timer, dd->ipath_hol_timer.expires);
}

/*
 * link is up, continue any user processes, and ensure timer
 * is a nop, if running.  Let timer keep running, if set; it
 * will nop when it sees the link is up
 */
void ipath_hol_up(struct ipath_devdata *dd)
{
        ipath_hol_signal_up(dd);
        dd->ipath_hol_state = IPATH_HOL_UP;
}

/*
 * toggle the running/not running state of user proceses
 * to prevent HoL blocking on chip resources, but still allow
 * user processes to do link down special case handling.
 * Should only be called via the timer
 */
void ipath_hol_event(unsigned long opaque)
{
        struct ipath_devdata *dd = (struct ipath_devdata *)opaque;

        if (dd->ipath_hol_next == IPATH_HOL_DOWNSTOP
                && dd->ipath_hol_state != IPATH_HOL_UP) {
                dd->ipath_hol_next = IPATH_HOL_DOWNCONT;
                ipath_dbg("Stopping processes\n");
                ipath_hol_signal_down(dd);
        } else { /* may do "extra" if also in ipath_hol_up() */
                dd->ipath_hol_next = IPATH_HOL_DOWNSTOP;
                ipath_dbg("Continuing processes\n");
                ipath_hol_signal_up(dd);
        }
        if (dd->ipath_hol_state == IPATH_HOL_UP)
                ipath_dbg("link's up, don't resched timer\n");
        else {
                dd->ipath_hol_timer.expires = jiffies +
                        msecs_to_jiffies(ipath_hol_timeout_ms);
                mod_timer(&dd->ipath_hol_timer,
                        dd->ipath_hol_timer.expires);
        }
}

int ipath_set_rx_pol_inv(struct ipath_devdata *dd, u8 new_pol_inv)
{
        u64 val;

        if (new_pol_inv > INFINIPATH_XGXS_RX_POL_MASK)
                return -1;
        if (dd->ipath_rx_pol_inv != new_pol_inv) {
                dd->ipath_rx_pol_inv = new_pol_inv;
                val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_xgxsconfig);
                val &= ~(INFINIPATH_XGXS_RX_POL_MASK <<
                         INFINIPATH_XGXS_RX_POL_SHIFT);
                val |= ((u64)dd->ipath_rx_pol_inv) <<
                        INFINIPATH_XGXS_RX_POL_SHIFT;
                ipath_write_kreg(dd, dd->ipath_kregs->kr_xgxsconfig, val);
        }
        return 0;
}

/*
 * Disable and enable the armlaunch error.  Used for PIO bandwidth testing on
 * the 7220, which is count-based, rather than trigger-based.  Safe for the
 * driver check, since it's at init.   Not completely safe when used for
 * user-mode checking, since some error checking can be lost, but not
 * particularly risky, and only has problematic side-effects in the face of
 * very buggy user code.  There is no reference counting, but that's also
 * fine, given the intended use.
 */
void ipath_enable_armlaunch(struct ipath_devdata *dd)
{
        dd->ipath_lasterror &= ~INFINIPATH_E_SPIOARMLAUNCH;
        ipath_write_kreg(dd, dd->ipath_kregs->kr_errorclear,
                INFINIPATH_E_SPIOARMLAUNCH);
        dd->ipath_errormask |= INFINIPATH_E_SPIOARMLAUNCH;
        ipath_write_kreg(dd, dd->ipath_kregs->kr_errormask,
                dd->ipath_errormask);
}

void ipath_disable_armlaunch(struct ipath_devdata *dd)
{
        /* so don't re-enable if already set */
        dd->ipath_maskederrs &= ~INFINIPATH_E_SPIOARMLAUNCH;
        dd->ipath_errormask &= ~INFINIPATH_E_SPIOARMLAUNCH;
        ipath_write_kreg(dd, dd->ipath_kregs->kr_errormask,
                dd->ipath_errormask);
}

module_init(infinipath_init);
module_exit(infinipath_cleanup);