/*
 * Copyright IBM Corp. 2012
 *
 * Author(s):
 *   Jan Glauber <jang@linux.vnet.ibm.com>
 *
 * The System z PCI code is a rewrite from a prototype by
 * the following people (Kudoz!):
 *   Alexander Schmidt
 *   Christoph Raisch
 *   Hannes Hering
 *   Hoang-Nam Nguyen
 *   Jan-Bernd Themann
 *   Stefan Roscher
 *   Thomas Klein
 */

#define KMSG_COMPONENT "zpci"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/kernel_stat.h>
#include <linux/seq_file.h>
#include <linux/pci.h>
#include <linux/msi.h>

#include <asm/isc.h>
#include <asm/airq.h>
#include <asm/facility.h>
#include <asm/pci_insn.h>
#include <asm/pci_clp.h>
#include <asm/pci_dma.h>

#define DEBUG                           /* enable pr_debug */

#define SIC_IRQ_MODE_ALL                0
#define SIC_IRQ_MODE_SINGLE             1

#define ZPCI_NR_DMA_SPACES              1
#define ZPCI_NR_DEVICES                 CONFIG_PCI_NR_FUNCTIONS

/* list of all detected zpci devices */
static LIST_HEAD(zpci_list);
static DEFINE_SPINLOCK(zpci_list_lock);

static struct irq_chip zpci_irq_chip = {
        .name = "zPCI",
        .irq_unmask = pci_msi_unmask_irq,
        .irq_mask = pci_msi_mask_irq,
};

static DECLARE_BITMAP(zpci_domain, ZPCI_NR_DEVICES);
static DEFINE_SPINLOCK(zpci_domain_lock);

static struct airq_iv *zpci_aisb_iv;
static struct airq_iv *zpci_aibv[ZPCI_NR_DEVICES];

/* Adapter interrupt definitions */
static void zpci_irq_handler(struct airq_struct *airq);

static struct airq_struct zpci_airq = {
        .handler = zpci_irq_handler,
        .isc = PCI_ISC,
};

#define ZPCI_IOMAP_ENTRIES                                              \
        min(((unsigned long) CONFIG_PCI_NR_FUNCTIONS * PCI_BAR_COUNT),  \
            ZPCI_IOMAP_MAX_ENTRIES)

static DEFINE_SPINLOCK(zpci_iomap_lock);
static unsigned long *zpci_iomap_bitmap;
struct zpci_iomap_entry *zpci_iomap_start;
EXPORT_SYMBOL_GPL(zpci_iomap_start);

static struct kmem_cache *zdev_fmb_cache;

struct zpci_dev *get_zdev_by_fid(u32 fid)
{
        struct zpci_dev *tmp, *zdev = NULL;

        spin_lock(&zpci_list_lock);
        list_for_each_entry(tmp, &zpci_list, entry) {
                if (tmp->fid == fid) {
                        zdev = tmp;
                        break;
                }
        }
        spin_unlock(&zpci_list_lock);
        return zdev;
}

static struct zpci_dev *get_zdev_by_bus(struct pci_bus *bus)
{
        return (bus && bus->sysdata) ? (struct zpci_dev *) bus->sysdata : NULL;
}

int pci_domain_nr(struct pci_bus *bus)
{
        return ((struct zpci_dev *) bus->sysdata)->domain;
}
EXPORT_SYMBOL_GPL(pci_domain_nr);

int pci_proc_domain(struct pci_bus *bus)
{
        return pci_domain_nr(bus);
}
EXPORT_SYMBOL_GPL(pci_proc_domain);

/* Modify PCI: Register adapter interruptions */
static int zpci_set_airq(struct zpci_dev *zdev)
{
        u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT);
        struct zpci_fib fib = {0};

        fib.isc = PCI_ISC;
        fib.sum = 1;            /* enable summary notifications */
        fib.noi = airq_iv_end(zdev->aibv);
        fib.aibv = (unsigned long) zdev->aibv->vector;
        fib.aibvo = 0;          /* each zdev has its own interrupt vector */
        fib.aisb = (unsigned long) zpci_aisb_iv->vector + (zdev->aisb/64)*8;
        fib.aisbo = zdev->aisb & 63;

        return zpci_mod_fc(req, &fib);
}

struct mod_pci_args {
        u64 base;
        u64 limit;
        u64 iota;
        u64 fmb_addr;
};

static int mod_pci(struct zpci_dev *zdev, int fn, u8 dmaas, struct mod_pci_args *args)
{
        u64 req = ZPCI_CREATE_REQ(zdev->fh, dmaas, fn);
        struct zpci_fib fib = {0};

        fib.pba = args->base;
        fib.pal = args->limit;
        fib.iota = args->iota;
        fib.fmb_addr = args->fmb_addr;

        return zpci_mod_fc(req, &fib);
}

/* Modify PCI: Register I/O address translation parameters */
int zpci_register_ioat(struct zpci_dev *zdev, u8 dmaas,
                       u64 base, u64 limit, u64 iota)
{
        struct mod_pci_args args = { base, limit, iota, 0 };

        WARN_ON_ONCE(iota & 0x3fff);
        args.iota |= ZPCI_IOTA_RTTO_FLAG;
        return mod_pci(zdev, ZPCI_MOD_FC_REG_IOAT, dmaas, &args);
}

/* Modify PCI: Unregister I/O address translation parameters */
int zpci_unregister_ioat(struct zpci_dev *zdev, u8 dmaas)
{
        struct mod_pci_args args = { 0, 0, 0, 0 };

        return mod_pci(zdev, ZPCI_MOD_FC_DEREG_IOAT, dmaas, &args);
}

/* Modify PCI: Unregister adapter interruptions */
static int zpci_clear_airq(struct zpci_dev *zdev)
{
        struct mod_pci_args args = { 0, 0, 0, 0 };

        return mod_pci(zdev, ZPCI_MOD_FC_DEREG_INT, 0, &args);
}

/* Modify PCI: Set PCI function measurement parameters */
int zpci_fmb_enable_device(struct zpci_dev *zdev)
{
        struct mod_pci_args args = { 0, 0, 0, 0 };

        if (zdev->fmb)
                return -EINVAL;

        zdev->fmb = kmem_cache_zalloc(zdev_fmb_cache, GFP_KERNEL);
        if (!zdev->fmb)
                return -ENOMEM;
        WARN_ON((u64) zdev->fmb & 0xf);

        /* reset software counters */
        atomic64_set(&zdev->allocated_pages, 0);
        atomic64_set(&zdev->mapped_pages, 0);
        atomic64_set(&zdev->unmapped_pages, 0);

        args.fmb_addr = virt_to_phys(zdev->fmb);
        return mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args);
}

/* Modify PCI: Disable PCI function measurement */
int zpci_fmb_disable_device(struct zpci_dev *zdev)
{
        struct mod_pci_args args = { 0, 0, 0, 0 };
        int rc;

        if (!zdev->fmb)
                return -EINVAL;

        /* Function measurement is disabled if fmb address is zero */
        rc = mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args);

        kmem_cache_free(zdev_fmb_cache, zdev->fmb);
        zdev->fmb = NULL;
        return rc;
}

#define ZPCI_PCIAS_CFGSPC       15

static int zpci_cfg_load(struct zpci_dev *zdev, int offset, u32 *val, u8 len)
{
        u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
        u64 data;
        int rc;

        rc = zpci_load(&data, req, offset);
        if (!rc) {
                data = data << ((8 - len) * 8);
                data = le64_to_cpu(data);
                *val = (u32) data;
        } else
                *val = 0xffffffff;
        return rc;
}

static int zpci_cfg_store(struct zpci_dev *zdev, int offset, u32 val, u8 len)
{
        u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
        u64 data = val;
        int rc;

        data = cpu_to_le64(data);
        data = data >> ((8 - len) * 8);
        rc = zpci_store(data, req, offset);
        return rc;
}

void pcibios_fixup_bus(struct pci_bus *bus)
{
}

resource_size_t pcibios_align_resource(void *data, const struct resource *res,
                                       resource_size_t size,
                                       resource_size_t align)
{
        return 0;
}

/* combine single writes by using store-block insn */
void __iowrite64_copy(void __iomem *to, const void *from, size_t count)
{
       zpci_memcpy_toio(to, from, count);
}

/* Create a virtual mapping cookie for a PCI BAR */
void __iomem *pci_iomap_range(struct pci_dev *pdev,
                              int bar,
                              unsigned long offset,
                              unsigned long max)
{
        struct zpci_dev *zdev = to_zpci(pdev);
        int idx;

        if (!pci_resource_len(pdev, bar))
                return NULL;

        idx = zdev->bars[bar].map_idx;
        spin_lock(&zpci_iomap_lock);
        /* Detect overrun */
        WARN_ON(!++zpci_iomap_start[idx].count);
        zpci_iomap_start[idx].fh = zdev->fh;
        zpci_iomap_start[idx].bar = bar;
        spin_unlock(&zpci_iomap_lock);

        return (void __iomem *) ZPCI_ADDR(idx) + offset;
}
EXPORT_SYMBOL(pci_iomap_range);

void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
{
        return pci_iomap_range(dev, bar, 0, maxlen);
}
EXPORT_SYMBOL(pci_iomap);

void pci_iounmap(struct pci_dev *pdev, void __iomem *addr)
{
        unsigned int idx = ZPCI_IDX(addr);

        spin_lock(&zpci_iomap_lock);
        /* Detect underrun */
        WARN_ON(!zpci_iomap_start[idx].count);
        if (!--zpci_iomap_start[idx].count) {
                zpci_iomap_start[idx].fh = 0;
                zpci_iomap_start[idx].bar = 0;
        }
        spin_unlock(&zpci_iomap_lock);
}
EXPORT_SYMBOL(pci_iounmap);

static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
                    int size, u32 *val)
{
        struct zpci_dev *zdev = get_zdev_by_bus(bus);
        int ret;

        if (!zdev || devfn != ZPCI_DEVFN)
                ret = -ENODEV;
        else
                ret = zpci_cfg_load(zdev, where, val, size);

        return ret;
}

static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
                     int size, u32 val)
{
        struct zpci_dev *zdev = get_zdev_by_bus(bus);
        int ret;

        if (!zdev || devfn != ZPCI_DEVFN)
                ret = -ENODEV;
        else
                ret = zpci_cfg_store(zdev, where, val, size);

        return ret;
}

static struct pci_ops pci_root_ops = {
        .read = pci_read,
        .write = pci_write,
};

static void zpci_irq_handler(struct airq_struct *airq)
{
        unsigned long si, ai;
        struct airq_iv *aibv;
        int irqs_on = 0;

        inc_irq_stat(IRQIO_PCI);
        for (si = 0;;) {
                /* Scan adapter summary indicator bit vector */
                si = airq_iv_scan(zpci_aisb_iv, si, airq_iv_end(zpci_aisb_iv));
                if (si == -1UL) {
                        if (irqs_on++)
                                /* End of second scan with interrupts on. */
                                break;
                        /* First scan complete, reenable interrupts. */
                        zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC);
                        si = 0;
                        continue;
                }

                /* Scan the adapter interrupt vector for this device. */
                aibv = zpci_aibv[si];
                for (ai = 0;;) {
                        ai = airq_iv_scan(aibv, ai, airq_iv_end(aibv));
                        if (ai == -1UL)
                                break;
                        inc_irq_stat(IRQIO_MSI);
                        airq_iv_lock(aibv, ai);
                        generic_handle_irq(airq_iv_get_data(aibv, ai));
                        airq_iv_unlock(aibv, ai);
                }
        }
}

int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
{
        struct zpci_dev *zdev = to_zpci(pdev);
        unsigned int hwirq, msi_vecs;
        unsigned long aisb;
        struct msi_desc *msi;
        struct msi_msg msg;
        int rc, irq;

        if (type == PCI_CAP_ID_MSI && nvec > 1)
                return 1;
        msi_vecs = min_t(unsigned int, nvec, zdev->max_msi);

        /* Allocate adapter summary indicator bit */
        rc = -EIO;
        aisb = airq_iv_alloc_bit(zpci_aisb_iv);
        if (aisb == -1UL)
                goto out;
        zdev->aisb = aisb;

        /* Create adapter interrupt vector */
        rc = -ENOMEM;
        zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK);
        if (!zdev->aibv)
                goto out_si;

        /* Wire up shortcut pointer */
        zpci_aibv[aisb] = zdev->aibv;

        /* Request MSI interrupts */
        hwirq = 0;
        for_each_pci_msi_entry(msi, pdev) {
                rc = -EIO;
                irq = irq_alloc_desc(0);        /* Alloc irq on node 0 */
                if (irq < 0)
                        goto out_msi;
                rc = irq_set_msi_desc(irq, msi);
                if (rc)
                        goto out_msi;
                irq_set_chip_and_handler(irq, &zpci_irq_chip,
                                         handle_simple_irq);
                msg.data = hwirq;
                msg.address_lo = zdev->msi_addr & 0xffffffff;
                msg.address_hi = zdev->msi_addr >> 32;
                pci_write_msi_msg(irq, &msg);
                airq_iv_set_data(zdev->aibv, hwirq, irq);
                hwirq++;
        }

        /* Enable adapter interrupts */
        rc = zpci_set_airq(zdev);
        if (rc)
                goto out_msi;

        return (msi_vecs == nvec) ? 0 : msi_vecs;

out_msi:
        for_each_pci_msi_entry(msi, pdev) {
                if (hwirq-- == 0)
                        break;
                irq_set_msi_desc(msi->irq, NULL);
                irq_free_desc(msi->irq);
                msi->msg.address_lo = 0;
                msi->msg.address_hi = 0;
                msi->msg.data = 0;
                msi->irq = 0;
        }
        zpci_aibv[aisb] = NULL;
        airq_iv_release(zdev->aibv);
out_si:
        airq_iv_free_bit(zpci_aisb_iv, aisb);
out:
        return rc;
}

void arch_teardown_msi_irqs(struct pci_dev *pdev)
{
        struct zpci_dev *zdev = to_zpci(pdev);
        struct msi_desc *msi;
        int rc;

        /* Disable adapter interrupts */
        rc = zpci_clear_airq(zdev);
        if (rc)
                return;

        /* Release MSI interrupts */
        for_each_pci_msi_entry(msi, pdev) {
                if (msi->msi_attrib.is_msix)
                        __pci_msix_desc_mask_irq(msi, 1);
                else
                        __pci_msi_desc_mask_irq(msi, 1, 1);
                irq_set_msi_desc(msi->irq, NULL);
                irq_free_desc(msi->irq);
                msi->msg.address_lo = 0;
                msi->msg.address_hi = 0;
                msi->msg.data = 0;
                msi->irq = 0;
        }

        zpci_aibv[zdev->aisb] = NULL;
        airq_iv_release(zdev->aibv);
        airq_iv_free_bit(zpci_aisb_iv, zdev->aisb);
}

static void zpci_map_resources(struct pci_dev *pdev)
{
        resource_size_t len;
        int i;

        for (i = 0; i < PCI_BAR_COUNT; i++) {
                len = pci_resource_len(pdev, i);
                if (!len)
                        continue;
                pdev->resource[i].start =
                        (resource_size_t __force) pci_iomap(pdev, i, 0);
                pdev->resource[i].end = pdev->resource[i].start + len - 1;
        }
}

static void zpci_unmap_resources(struct pci_dev *pdev)
{
        resource_size_t len;
        int i;

        for (i = 0; i < PCI_BAR_COUNT; i++) {
                len = pci_resource_len(pdev, i);
                if (!len)
                        continue;
                pci_iounmap(pdev, (void __iomem __force *)
                            pdev->resource[i].start);
        }
}

static int __init zpci_irq_init(void)
{
        int rc;

        rc = register_adapter_interrupt(&zpci_airq);
        if (rc)
                goto out;
        /* Set summary to 1 to be called every time for the ISC. */
        *zpci_airq.lsi_ptr = 1;

        rc = -ENOMEM;
        zpci_aisb_iv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC);
        if (!zpci_aisb_iv)
                goto out_airq;

        zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC);
        return 0;

out_airq:
        unregister_adapter_interrupt(&zpci_airq);
out:
        return rc;
}

static void zpci_irq_exit(void)
{
        airq_iv_release(zpci_aisb_iv);
        unregister_adapter_interrupt(&zpci_airq);
}

static int zpci_alloc_iomap(struct zpci_dev *zdev)
{
        unsigned long entry;

        spin_lock(&zpci_iomap_lock);
        entry = find_first_zero_bit(zpci_iomap_bitmap, ZPCI_IOMAP_ENTRIES);
        if (entry == ZPCI_IOMAP_ENTRIES) {
                spin_unlock(&zpci_iomap_lock);
                return -ENOSPC;
        }
        set_bit(entry, zpci_iomap_bitmap);
        spin_unlock(&zpci_iomap_lock);
        return entry;
}

static void zpci_free_iomap(struct zpci_dev *zdev, int entry)
{
        spin_lock(&zpci_iomap_lock);
        memset(&zpci_iomap_start[entry], 0, sizeof(struct zpci_iomap_entry));
        clear_bit(entry, zpci_iomap_bitmap);
        spin_unlock(&zpci_iomap_lock);
}

static struct resource *__alloc_res(struct zpci_dev *zdev, unsigned long start,
                                    unsigned long size, unsigned long flags)
{
        struct resource *r;

        r = kzalloc(sizeof(*r), GFP_KERNEL);
        if (!r)
                return NULL;

        r->start = start;
        r->end = r->start + size - 1;
        r->flags = flags;
        r->name = zdev->res_name;

        if (request_resource(&iomem_resource, r)) {
                kfree(r);
                return NULL;
        }
        return r;
}

static int zpci_setup_bus_resources(struct zpci_dev *zdev,
                                    struct list_head *resources)
{
        unsigned long addr, size, flags;
        struct resource *res;
        int i, entry;

        snprintf(zdev->res_name, sizeof(zdev->res_name),
                 "PCI Bus %04x:%02x", zdev->domain, ZPCI_BUS_NR);

        for (i = 0; i < PCI_BAR_COUNT; i++) {
                if (!zdev->bars[i].size)
                        continue;
                entry = zpci_alloc_iomap(zdev);
                if (entry < 0)
                        return entry;
                zdev->bars[i].map_idx = entry;

                /* only MMIO is supported */
                flags = IORESOURCE_MEM;
                if (zdev->bars[i].val & 8)
                        flags |= IORESOURCE_PREFETCH;
                if (zdev->bars[i].val & 4)
                        flags |= IORESOURCE_MEM_64;

                addr = ZPCI_ADDR(entry);
                size = 1UL << zdev->bars[i].size;

                res = __alloc_res(zdev, addr, size, flags);
                if (!res) {
                        zpci_free_iomap(zdev, entry);
                        return -ENOMEM;
                }
                zdev->bars[i].res = res;
                pci_add_resource(resources, res);
        }

        return 0;
}

static void zpci_cleanup_bus_resources(struct zpci_dev *zdev)
{
        int i;

        for (i = 0; i < PCI_BAR_COUNT; i++) {
                if (!zdev->bars[i].size || !zdev->bars[i].res)
                        continue;

                zpci_free_iomap(zdev, zdev->bars[i].map_idx);
                release_resource(zdev->bars[i].res);
                kfree(zdev->bars[i].res);
        }
}

int pcibios_add_device(struct pci_dev *pdev)
{
        struct resource *res;
        int i;

        pdev->dev.groups = zpci_attr_groups;
        pdev->dev.archdata.dma_ops = &s390_pci_dma_ops;
        zpci_map_resources(pdev);

        for (i = 0; i < PCI_BAR_COUNT; i++) {
                res = &pdev->resource[i];
                if (res->parent || !res->flags)
                        continue;
                pci_claim_resource(pdev, i);
        }

        return 0;
}

void pcibios_release_device(struct pci_dev *pdev)
{
        zpci_unmap_resources(pdev);
}

int pcibios_enable_device(struct pci_dev *pdev, int mask)
{
        struct zpci_dev *zdev = to_zpci(pdev);

        zpci_debug_init_device(zdev, dev_name(&pdev->dev));
        zpci_fmb_enable_device(zdev);

        return pci_enable_resources(pdev, mask);
}

void pcibios_disable_device(struct pci_dev *pdev)
{
        struct zpci_dev *zdev = to_zpci(pdev);

        zpci_fmb_disable_device(zdev);
        zpci_debug_exit_device(zdev);
}

#ifdef CONFIG_HIBERNATE_CALLBACKS
static int zpci_restore(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct zpci_dev *zdev = to_zpci(pdev);
        int ret = 0;

        if (zdev->state != ZPCI_FN_STATE_ONLINE)
                goto out;

        ret = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES);
        if (ret)
                goto out;

        zpci_map_resources(pdev);
        zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
                           (u64) zdev->dma_table);

out:
        return ret;
}

static int zpci_freeze(struct device *dev)
{
        struct pci_dev *pdev = to_pci_dev(dev);
        struct zpci_dev *zdev = to_zpci(pdev);

        if (zdev->state != ZPCI_FN_STATE_ONLINE)
                return 0;

        zpci_unregister_ioat(zdev, 0);
        zpci_unmap_resources(pdev);
        return clp_disable_fh(zdev);
}

struct dev_pm_ops pcibios_pm_ops = {
        .thaw_noirq = zpci_restore,
        .freeze_noirq = zpci_freeze,
        .restore_noirq = zpci_restore,
        .poweroff_noirq = zpci_freeze,
};
#endif /* CONFIG_HIBERNATE_CALLBACKS */

static int zpci_alloc_domain(struct zpci_dev *zdev)
{
        spin_lock(&zpci_domain_lock);
        zdev->domain = find_first_zero_bit(zpci_domain, ZPCI_NR_DEVICES);
        if (zdev->domain == ZPCI_NR_DEVICES) {
                spin_unlock(&zpci_domain_lock);
                return -ENOSPC;
        }
        set_bit(zdev->domain, zpci_domain);
        spin_unlock(&zpci_domain_lock);
        return 0;
}

static void zpci_free_domain(struct zpci_dev *zdev)
{
        spin_lock(&zpci_domain_lock);
        clear_bit(zdev->domain, zpci_domain);
        spin_unlock(&zpci_domain_lock);
}

void pcibios_remove_bus(struct pci_bus *bus)
{
        struct zpci_dev *zdev = get_zdev_by_bus(bus);

        zpci_exit_slot(zdev);
        zpci_cleanup_bus_resources(zdev);
        zpci_free_domain(zdev);

        spin_lock(&zpci_list_lock);
        list_del(&zdev->entry);
        spin_unlock(&zpci_list_lock);

        kfree(zdev);
}

static int zpci_scan_bus(struct zpci_dev *zdev)
{
        LIST_HEAD(resources);
        int ret;

        ret = zpci_setup_bus_resources(zdev, &resources);
        if (ret)
                goto error;

        zdev->bus = pci_scan_root_bus(NULL, ZPCI_BUS_NR, &pci_root_ops,
                                      zdev, &resources);
        if (!zdev->bus) {
                ret = -EIO;
                goto error;
        }
        zdev->bus->max_bus_speed = zdev->max_bus_speed;
        pci_bus_add_devices(zdev->bus);
        return 0;

error:
        zpci_cleanup_bus_resources(zdev);
        pci_free_resource_list(&resources);
        return ret;
}

int zpci_enable_device(struct zpci_dev *zdev)
{
        int rc;

        rc = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES);
        if (rc)
                goto out;

        rc = zpci_dma_init_device(zdev);
        if (rc)
                goto out_dma;

        zdev->state = ZPCI_FN_STATE_ONLINE;
        return 0;

out_dma:
        clp_disable_fh(zdev);
out:
        return rc;
}
EXPORT_SYMBOL_GPL(zpci_enable_device);

int zpci_disable_device(struct zpci_dev *zdev)
{
        zpci_dma_exit_device(zdev);
        return clp_disable_fh(zdev);
}
EXPORT_SYMBOL_GPL(zpci_disable_device);

int zpci_create_device(struct zpci_dev *zdev)
{
        int rc;

        rc = zpci_alloc_domain(zdev);
        if (rc)
                goto out;

        mutex_init(&zdev->lock);
        if (zdev->state == ZPCI_FN_STATE_CONFIGURED) {
                rc = zpci_enable_device(zdev);
                if (rc)
                        goto out_free;
        }
        rc = zpci_scan_bus(zdev);
        if (rc)
                goto out_disable;

        spin_lock(&zpci_list_lock);
        list_add_tail(&zdev->entry, &zpci_list);
        spin_unlock(&zpci_list_lock);

        zpci_init_slot(zdev);

        return 0;

out_disable:
        if (zdev->state == ZPCI_FN_STATE_ONLINE)
                zpci_disable_device(zdev);
out_free:
        zpci_free_domain(zdev);
out:
        return rc;
}

void zpci_stop_device(struct zpci_dev *zdev)
{
        zpci_dma_exit_device(zdev);
        /*
         * Note: SCLP disables fh via set-pci-fn so don't
         * do that here.
         */
}
EXPORT_SYMBOL_GPL(zpci_stop_device);

static inline int barsize(u8 size)
{
        return (size) ? (1 << size) >> 10 : 0;
}

static int zpci_mem_init(void)
{
        BUILD_BUG_ON(!is_power_of_2(__alignof__(struct zpci_fmb)) ||
                     __alignof__(struct zpci_fmb) < sizeof(struct zpci_fmb));

        zdev_fmb_cache = kmem_cache_create("PCI_FMB_cache", sizeof(struct zpci_fmb),
                                           __alignof__(struct zpci_fmb), 0, NULL);
        if (!zdev_fmb_cache)
                goto error_fmb;

        zpci_iomap_start = kcalloc(ZPCI_IOMAP_ENTRIES,
                                   sizeof(*zpci_iomap_start), GFP_KERNEL);
        if (!zpci_iomap_start)
                goto error_iomap;

        zpci_iomap_bitmap = kcalloc(BITS_TO_LONGS(ZPCI_IOMAP_ENTRIES),
                                    sizeof(*zpci_iomap_bitmap), GFP_KERNEL);
        if (!zpci_iomap_bitmap)
                goto error_iomap_bitmap;

        return 0;
error_iomap_bitmap:
        kfree(zpci_iomap_start);
error_iomap:
        kmem_cache_destroy(zdev_fmb_cache);
error_fmb:
        return -ENOMEM;
}

static void zpci_mem_exit(void)
{
        kfree(zpci_iomap_bitmap);
        kfree(zpci_iomap_start);
        kmem_cache_destroy(zdev_fmb_cache);
}

static unsigned int s390_pci_probe = 1;
static unsigned int s390_pci_initialized;

char * __init pcibios_setup(char *str)
{
        if (!strcmp(str, "off")) {
                s390_pci_probe = 0;
                return NULL;
        }
        return str;
}

bool zpci_is_enabled(void)
{
        return s390_pci_initialized;
}

static int __init pci_base_init(void)
{
        int rc;

        if (!s390_pci_probe)
                return 0;

        if (!test_facility(69) || !test_facility(71) || !test_facility(72))
                return 0;

        rc = zpci_debug_init();
        if (rc)
                goto out;

        rc = zpci_mem_init();
        if (rc)
                goto out_mem;

        rc = zpci_irq_init();
        if (rc)
                goto out_irq;

        rc = zpci_dma_init();
        if (rc)
                goto out_dma;

        rc = clp_scan_pci_devices();
        if (rc)
                goto out_find;

        s390_pci_initialized = 1;
        return 0;

out_find:
        zpci_dma_exit();
out_dma:
        zpci_irq_exit();
out_irq:
        zpci_mem_exit();
out_mem:
        zpci_debug_exit();
out:
        return rc;
}
subsys_initcall_sync(pci_base_init);

void zpci_rescan(void)
{
        if (zpci_is_enabled())
                clp_rescan_pci_devices_simple();
}