/*
 * Support PCI/PCIe on PowerNV platforms
 *
 * Copyright 2011 Benjamin Herrenschmidt, IBM Corp.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#undef DEBUG

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/msi.h>

#include <asm/sections.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/machdep.h>
#include <asm/ppc-pci.h>
#include <asm/opal.h>
#include <asm/iommu.h>
#include <asm/tce.h>

#include "powernv.h"
#include "pci.h"

static int __pe_printk(const char *level, const struct pnv_ioda_pe *pe,
                       struct va_format *vaf)
{
        char pfix[32];

        if (pe->pdev)
                strlcpy(pfix, dev_name(&pe->pdev->dev), sizeof(pfix));
        else
                sprintf(pfix, "%04x:%02x     ",
                        pci_domain_nr(pe->pbus), pe->pbus->number);
        return printk("pci %s%s: [PE# %.3d] %pV", level, pfix, pe->pe_number, vaf);
}

#define define_pe_printk_level(func, kern_level)                \
static int func(const struct pnv_ioda_pe *pe, const char *fmt, ...)     \
{                                                               \
        struct va_format vaf;                                   \
        va_list args;                                           \
        int r;                                                  \
                                                                \
        va_start(args, fmt);                                    \
                                                                \
        vaf.fmt = fmt;                                          \
        vaf.va = &args;                                         \
                                                                \
        r = __pe_printk(kern_level, pe, &vaf);                  \
        va_end(args);                                           \
                                                                \
        return r;                                               \
}                                                               \

define_pe_printk_level(pe_err, KERN_ERR);
define_pe_printk_level(pe_warn, KERN_WARNING);
define_pe_printk_level(pe_info, KERN_INFO);

static struct pci_dn *pnv_ioda_get_pdn(struct pci_dev *dev)
{
        struct device_node *np;

        np = pci_device_to_OF_node(dev);
        if (!np)
                return NULL;
        return PCI_DN(np);
}

static int __devinit pnv_ioda_alloc_pe(struct pnv_phb *phb)
{
        unsigned long pe;

        do {
                pe = find_next_zero_bit(phb->ioda.pe_alloc,
                                        phb->ioda.total_pe, 0);
                if (pe >= phb->ioda.total_pe)
                        return IODA_INVALID_PE;
        } while(test_and_set_bit(pe, phb->ioda.pe_alloc));

        phb->ioda.pe_array[pe].pe_number = pe;
        return pe;
}

static void __devinit pnv_ioda_free_pe(struct pnv_phb *phb, int pe)
{
        WARN_ON(phb->ioda.pe_array[pe].pdev);

        memset(&phb->ioda.pe_array[pe], 0, sizeof(struct pnv_ioda_pe));
        clear_bit(pe, phb->ioda.pe_alloc);
}

/* Currently those 2 are only used when MSIs are enabled, this will change
 * but in the meantime, we need to protect them to avoid warnings
 */
#ifdef CONFIG_PCI_MSI
static struct pnv_ioda_pe * __devinit pnv_ioda_get_pe(struct pci_dev *dev)
{
        struct pci_controller *hose = pci_bus_to_host(dev->bus);
        struct pnv_phb *phb = hose->private_data;
        struct pci_dn *pdn = pnv_ioda_get_pdn(dev);

        if (!pdn)
                return NULL;
        if (pdn->pe_number == IODA_INVALID_PE)
                return NULL;
        return &phb->ioda.pe_array[pdn->pe_number];
}
#endif /* CONFIG_PCI_MSI */

static int __devinit pnv_ioda_configure_pe(struct pnv_phb *phb,
                                           struct pnv_ioda_pe *pe)
{
        struct pci_dev *parent;
        uint8_t bcomp, dcomp, fcomp;
        long rc, rid_end, rid;

        /* Bus validation ? */
        if (pe->pbus) {
                int count;

                dcomp = OPAL_IGNORE_RID_DEVICE_NUMBER;
                fcomp = OPAL_IGNORE_RID_FUNCTION_NUMBER;
                parent = pe->pbus->self;
                if (pe->flags & PNV_IODA_PE_BUS_ALL)
                        count = pe->pbus->busn_res.end - pe->pbus->busn_res.start + 1;
                else
                        count = 1;

                switch(count) {
                case  1: bcomp = OpalPciBusAll;         break;
                case  2: bcomp = OpalPciBus7Bits;       break;
                case  4: bcomp = OpalPciBus6Bits;       break;
                case  8: bcomp = OpalPciBus5Bits;       break;
                case 16: bcomp = OpalPciBus4Bits;       break;
                case 32: bcomp = OpalPciBus3Bits;       break;
                default:
                        pr_err("%s: Number of subordinate busses %d"
                               " unsupported\n",
                               pci_name(pe->pbus->self), count);
                        /* Do an exact match only */
                        bcomp = OpalPciBusAll;
                }
                rid_end = pe->rid + (count << 8);
        } else {
                parent = pe->pdev->bus->self;
                bcomp = OpalPciBusAll;
                dcomp = OPAL_COMPARE_RID_DEVICE_NUMBER;
                fcomp = OPAL_COMPARE_RID_FUNCTION_NUMBER;
                rid_end = pe->rid + 1;
        }

        /* Associate PE in PELT */
        rc = opal_pci_set_pe(phb->opal_id, pe->pe_number, pe->rid,
                             bcomp, dcomp, fcomp, OPAL_MAP_PE);
        if (rc) {
                pe_err(pe, "OPAL error %ld trying to setup PELT table\n", rc);
                return -ENXIO;
        }
        opal_pci_eeh_freeze_clear(phb->opal_id, pe->pe_number,
                                  OPAL_EEH_ACTION_CLEAR_FREEZE_ALL);

        /* Add to all parents PELT-V */
        while (parent) {
                struct pci_dn *pdn = pnv_ioda_get_pdn(parent);
                if (pdn && pdn->pe_number != IODA_INVALID_PE) {
                        rc = opal_pci_set_peltv(phb->opal_id, pdn->pe_number,
                                                pe->pe_number, OPAL_ADD_PE_TO_DOMAIN);
                        /* XXX What to do in case of error ? */
                }
                parent = parent->bus->self;
        }
        /* Setup reverse map */
        for (rid = pe->rid; rid < rid_end; rid++)
                phb->ioda.pe_rmap[rid] = pe->pe_number;

        /* Setup one MVTs on IODA1 */
        if (phb->type == PNV_PHB_IODA1) {
                pe->mve_number = pe->pe_number;
                rc = opal_pci_set_mve(phb->opal_id, pe->mve_number,
                                      pe->pe_number);
                if (rc) {
                        pe_err(pe, "OPAL error %ld setting up MVE %d\n",
                               rc, pe->mve_number);
                        pe->mve_number = -1;
                } else {
                        rc = opal_pci_set_mve_enable(phb->opal_id,
                                                     pe->mve_number, OPAL_ENABLE_MVE);
                        if (rc) {
                                pe_err(pe, "OPAL error %ld enabling MVE %d\n",
                                       rc, pe->mve_number);
                                pe->mve_number = -1;
                        }
                }
        } else if (phb->type == PNV_PHB_IODA2)
                pe->mve_number = 0;

        return 0;
}

static void __devinit pnv_ioda_link_pe_by_weight(struct pnv_phb *phb,
                                                 struct pnv_ioda_pe *pe)
{
        struct pnv_ioda_pe *lpe;

        list_for_each_entry(lpe, &phb->ioda.pe_dma_list, dma_link) {
                if (lpe->dma_weight < pe->dma_weight) {
                        list_add_tail(&pe->dma_link, &lpe->dma_link);
                        return;
                }
        }
        list_add_tail(&pe->dma_link, &phb->ioda.pe_dma_list);
}

static unsigned int pnv_ioda_dma_weight(struct pci_dev *dev)
{
        /* This is quite simplistic. The "base" weight of a device
         * is 10. 0 means no DMA is to be accounted for it.
         */

        /* If it's a bridge, no DMA */
        if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL)
                return 0;

        /* Reduce the weight of slow USB controllers */
        if (dev->class == PCI_CLASS_SERIAL_USB_UHCI ||
            dev->class == PCI_CLASS_SERIAL_USB_OHCI ||
            dev->class == PCI_CLASS_SERIAL_USB_EHCI)
                return 3;

        /* Increase the weight of RAID (includes Obsidian) */
        if ((dev->class >> 8) == PCI_CLASS_STORAGE_RAID)
                return 15;

        /* Default */
        return 10;
}

#if 0
static struct pnv_ioda_pe * __devinit pnv_ioda_setup_dev_PE(struct pci_dev *dev)
{
        struct pci_controller *hose = pci_bus_to_host(dev->bus);
        struct pnv_phb *phb = hose->private_data;
        struct pci_dn *pdn = pnv_ioda_get_pdn(dev);
        struct pnv_ioda_pe *pe;
        int pe_num;

        if (!pdn) {
                pr_err("%s: Device tree node not associated properly\n",
                           pci_name(dev));
                return NULL;
        }
        if (pdn->pe_number != IODA_INVALID_PE)
                return NULL;

        /* PE#0 has been pre-set */
        if (dev->bus->number == 0)
                pe_num = 0;
        else
                pe_num = pnv_ioda_alloc_pe(phb);
        if (pe_num == IODA_INVALID_PE) {
                pr_warning("%s: Not enough PE# available, disabling device\n",
                           pci_name(dev));
                return NULL;
        }

        /* NOTE: We get only one ref to the pci_dev for the pdn, not for the
         * pointer in the PE data structure, both should be destroyed at the
         * same time. However, this needs to be looked at more closely again
         * once we actually start removing things (Hotplug, SR-IOV, ...)
         *
         * At some point we want to remove the PDN completely anyways
         */
        pe = &phb->ioda.pe_array[pe_num];
        pci_dev_get(dev);
        pdn->pcidev = dev;
        pdn->pe_number = pe_num;
        pe->pdev = dev;
        pe->pbus = NULL;
        pe->tce32_seg = -1;
        pe->mve_number = -1;
        pe->rid = dev->bus->number << 8 | pdn->devfn;

        pe_info(pe, "Associated device to PE\n");

        if (pnv_ioda_configure_pe(phb, pe)) {
                /* XXX What do we do here ? */
                if (pe_num)
                        pnv_ioda_free_pe(phb, pe_num);
                pdn->pe_number = IODA_INVALID_PE;
                pe->pdev = NULL;
                pci_dev_put(dev);
                return NULL;
        }

        /* Assign a DMA weight to the device */
        pe->dma_weight = pnv_ioda_dma_weight(dev);
        if (pe->dma_weight != 0) {
                phb->ioda.dma_weight += pe->dma_weight;
                phb->ioda.dma_pe_count++;
        }

        /* Link the PE */
        pnv_ioda_link_pe_by_weight(phb, pe);

        return pe;
}
#endif /* Useful for SRIOV case */

static void pnv_ioda_setup_same_PE(struct pci_bus *bus, struct pnv_ioda_pe *pe)
{
        struct pci_dev *dev;

        list_for_each_entry(dev, &bus->devices, bus_list) {
                struct pci_dn *pdn = pnv_ioda_get_pdn(dev);

                if (pdn == NULL) {
                        pr_warn("%s: No device node associated with device !\n",
                                pci_name(dev));
                        continue;
                }
                pci_dev_get(dev);
                pdn->pcidev = dev;
                pdn->pe_number = pe->pe_number;
                pe->dma_weight += pnv_ioda_dma_weight(dev);
                if ((pe->flags & PNV_IODA_PE_BUS_ALL) && dev->subordinate)
                        pnv_ioda_setup_same_PE(dev->subordinate, pe);
        }
}

/*
 * There're 2 types of PCI bus sensitive PEs: One that is compromised of
 * single PCI bus. Another one that contains the primary PCI bus and its
 * subordinate PCI devices and buses. The second type of PE is normally
 * orgiriated by PCIe-to-PCI bridge or PLX switch downstream ports.
 */
static void __devinit pnv_ioda_setup_bus_PE(struct pci_bus *bus, int all)
{
        struct pci_controller *hose = pci_bus_to_host(bus);
        struct pnv_phb *phb = hose->private_data;
        struct pnv_ioda_pe *pe;
        int pe_num;

        pe_num = pnv_ioda_alloc_pe(phb);
        if (pe_num == IODA_INVALID_PE) {
                pr_warning("%s: Not enough PE# available for PCI bus %04x:%02x\n",
                        __func__, pci_domain_nr(bus), bus->number);
                return;
        }

        pe = &phb->ioda.pe_array[pe_num];
        pe->flags = (all ? PNV_IODA_PE_BUS_ALL : PNV_IODA_PE_BUS);
        pe->pbus = bus;
        pe->pdev = NULL;
        pe->tce32_seg = -1;
        pe->mve_number = -1;
        pe->rid = bus->busn_res.start << 8;
        pe->dma_weight = 0;

        if (all)
                pe_info(pe, "Secondary bus %d..%d associated with PE#%d\n",
                        bus->busn_res.start, bus->busn_res.end, pe_num);
        else
                pe_info(pe, "Secondary bus %d associated with PE#%d\n",
                        bus->busn_res.start, pe_num);

        if (pnv_ioda_configure_pe(phb, pe)) {
                /* XXX What do we do here ? */
                if (pe_num)
                        pnv_ioda_free_pe(phb, pe_num);
                pe->pbus = NULL;
                return;
        }

        /* Associate it with all child devices */
        pnv_ioda_setup_same_PE(bus, pe);

        /* Put PE to the list */
        list_add_tail(&pe->list, &phb->ioda.pe_list);

        /* Account for one DMA PE if at least one DMA capable device exist
         * below the bridge
         */
        if (pe->dma_weight != 0) {
                phb->ioda.dma_weight += pe->dma_weight;
                phb->ioda.dma_pe_count++;
        }

        /* Link the PE */
        pnv_ioda_link_pe_by_weight(phb, pe);
}

static void __devinit pnv_ioda_setup_PEs(struct pci_bus *bus)
{
        struct pci_dev *dev;

        pnv_ioda_setup_bus_PE(bus, 0);

        list_for_each_entry(dev, &bus->devices, bus_list) {
                if (dev->subordinate) {
                        if (pci_pcie_type(dev) == PCI_EXP_TYPE_PCI_BRIDGE)
                                pnv_ioda_setup_bus_PE(dev->subordinate, 1);
                        else
                                pnv_ioda_setup_PEs(dev->subordinate);
                }
        }
}

/*
 * Configure PEs so that the downstream PCI buses and devices
 * could have their associated PE#. Unfortunately, we didn't
 * figure out the way to identify the PLX bridge yet. So we
 * simply put the PCI bus and the subordinate behind the root
 * port to PE# here. The game rule here is expected to be changed
 * as soon as we can detected PLX bridge correctly.
 */
static void __devinit pnv_pci_ioda_setup_PEs(void)
{
        struct pci_controller *hose, *tmp;

        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
                pnv_ioda_setup_PEs(hose->bus);
        }
}

static void __devinit pnv_pci_ioda_dma_dev_setup(struct pnv_phb *phb,
                                                 struct pci_dev *dev)
{
        /* We delay DMA setup after we have assigned all PE# */
}

static void __devinit pnv_ioda_setup_bus_dma(struct pnv_ioda_pe *pe,
                                             struct pci_bus *bus)
{
        struct pci_dev *dev;

        list_for_each_entry(dev, &bus->devices, bus_list) {
                set_iommu_table_base(&dev->dev, &pe->tce32_table);
                if (dev->subordinate)
                        pnv_ioda_setup_bus_dma(pe, dev->subordinate);
        }
}

static void __devinit pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
                                                struct pnv_ioda_pe *pe,
                                                unsigned int base,
                                                unsigned int segs)
{

        struct page *tce_mem = NULL;
        const __be64 *swinvp;
        struct iommu_table *tbl;
        unsigned int i;
        int64_t rc;
        void *addr;

        /* 256M DMA window, 4K TCE pages, 8 bytes TCE */
#define TCE32_TABLE_SIZE        ((0x10000000 / 0x1000) * 8)

        /* XXX FIXME: Handle 64-bit only DMA devices */
        /* XXX FIXME: Provide 64-bit DMA facilities & non-4K TCE tables etc.. */
        /* XXX FIXME: Allocate multi-level tables on PHB3 */

        /* We shouldn't already have a 32-bit DMA associated */
        if (WARN_ON(pe->tce32_seg >= 0))
                return;

        /* Grab a 32-bit TCE table */
        pe->tce32_seg = base;
        pe_info(pe, " Setting up 32-bit TCE table at %08x..%08x\n",
                (base << 28), ((base + segs) << 28) - 1);

        /* XXX Currently, we allocate one big contiguous table for the
         * TCEs. We only really need one chunk per 256M of TCE space
         * (ie per segment) but that's an optimization for later, it
         * requires some added smarts with our get/put_tce implementation
         */
        tce_mem = alloc_pages_node(phb->hose->node, GFP_KERNEL,
                                   get_order(TCE32_TABLE_SIZE * segs));
        if (!tce_mem) {
                pe_err(pe, " Failed to allocate a 32-bit TCE memory\n");
                goto fail;
        }
        addr = page_address(tce_mem);
        memset(addr, 0, TCE32_TABLE_SIZE * segs);

        /* Configure HW */
        for (i = 0; i < segs; i++) {
                rc = opal_pci_map_pe_dma_window(phb->opal_id,
                                              pe->pe_number,
                                              base + i, 1,
                                              __pa(addr) + TCE32_TABLE_SIZE * i,
                                              TCE32_TABLE_SIZE, 0x1000);
                if (rc) {
                        pe_err(pe, " Failed to configure 32-bit TCE table,"
                               " err %ld\n", rc);
                        goto fail;
                }
        }

        /* Setup linux iommu table */
        tbl = &pe->tce32_table;
        pnv_pci_setup_iommu_table(tbl, addr, TCE32_TABLE_SIZE * segs,
                                  base << 28);

        /* OPAL variant of P7IOC SW invalidated TCEs */
        swinvp = of_get_property(phb->hose->dn, "ibm,opal-tce-kill", NULL);
        if (swinvp) {
                /* We need a couple more fields -- an address and a data
                 * to or.  Since the bus is only printed out on table free
                 * errors, and on the first pass the data will be a relative
                 * bus number, print that out instead.
                 */
                tbl->it_busno = 0;
                tbl->it_index = (unsigned long)ioremap(be64_to_cpup(swinvp), 8);
                tbl->it_type = TCE_PCI_SWINV_CREATE | TCE_PCI_SWINV_FREE
                        | TCE_PCI_SWINV_PAIR;
        }
        iommu_init_table(tbl, phb->hose->node);

        if (pe->pdev)
                set_iommu_table_base(&pe->pdev->dev, tbl);
        else
                pnv_ioda_setup_bus_dma(pe, pe->pbus);

        return;
 fail:
        /* XXX Failure: Try to fallback to 64-bit only ? */
        if (pe->tce32_seg >= 0)
                pe->tce32_seg = -1;
        if (tce_mem)
                __free_pages(tce_mem, get_order(TCE32_TABLE_SIZE * segs));
}

static void __devinit pnv_ioda_setup_dma(struct pnv_phb *phb)
{
        struct pci_controller *hose = phb->hose;
        unsigned int residual, remaining, segs, tw, base;
        struct pnv_ioda_pe *pe;

        /* If we have more PE# than segments available, hand out one
         * per PE until we run out and let the rest fail. If not,
         * then we assign at least one segment per PE, plus more based
         * on the amount of devices under that PE
         */
        if (phb->ioda.dma_pe_count > phb->ioda.tce32_count)
                residual = 0;
        else
                residual = phb->ioda.tce32_count -
                        phb->ioda.dma_pe_count;

        pr_info("PCI: Domain %04x has %ld available 32-bit DMA segments\n",
                hose->global_number, phb->ioda.tce32_count);
        pr_info("PCI: %d PE# for a total weight of %d\n",
                phb->ioda.dma_pe_count, phb->ioda.dma_weight);

        /* Walk our PE list and configure their DMA segments, hand them
         * out one base segment plus any residual segments based on
         * weight
         */
        remaining = phb->ioda.tce32_count;
        tw = phb->ioda.dma_weight;
        base = 0;
        list_for_each_entry(pe, &phb->ioda.pe_dma_list, dma_link) {
                if (!pe->dma_weight)
                        continue;
                if (!remaining) {
                        pe_warn(pe, "No DMA32 resources available\n");
                        continue;
                }
                segs = 1;
                if (residual) {
                        segs += ((pe->dma_weight * residual)  + (tw / 2)) / tw;
                        if (segs > remaining)
                                segs = remaining;
                }
                pe_info(pe, "DMA weight %d, assigned %d DMA32 segments\n",
                        pe->dma_weight, segs);
                pnv_pci_ioda_setup_dma_pe(phb, pe, base, segs);
                remaining -= segs;
                base += segs;
        }
}

#ifdef CONFIG_PCI_MSI
static int pnv_pci_ioda_msi_setup(struct pnv_phb *phb, struct pci_dev *dev,
                                  unsigned int hwirq, unsigned int is_64,
                                  struct msi_msg *msg)
{
        struct pnv_ioda_pe *pe = pnv_ioda_get_pe(dev);
        unsigned int xive_num = hwirq - phb->msi_base;
        uint64_t addr64;
        uint32_t addr32, data;
        int rc;

        /* No PE assigned ? bail out ... no MSI for you ! */
        if (pe == NULL)
                return -ENXIO;

        /* Check if we have an MVE */
        if (pe->mve_number < 0)
                return -ENXIO;

        /* Assign XIVE to PE */
        rc = opal_pci_set_xive_pe(phb->opal_id, pe->pe_number, xive_num);
        if (rc) {
                pr_warn("%s: OPAL error %d setting XIVE %d PE\n",
                        pci_name(dev), rc, xive_num);
                return -EIO;
        }

        if (is_64) {
                rc = opal_get_msi_64(phb->opal_id, pe->mve_number, xive_num, 1,
                                     &addr64, &data);
                if (rc) {
                        pr_warn("%s: OPAL error %d getting 64-bit MSI data\n",
                                pci_name(dev), rc);
                        return -EIO;
                }
                msg->address_hi = addr64 >> 32;
                msg->address_lo = addr64 & 0xfffffffful;
        } else {
                rc = opal_get_msi_32(phb->opal_id, pe->mve_number, xive_num, 1,
                                     &addr32, &data);
                if (rc) {
                        pr_warn("%s: OPAL error %d getting 32-bit MSI data\n",
                                pci_name(dev), rc);
                        return -EIO;
                }
                msg->address_hi = 0;
                msg->address_lo = addr32;
        }
        msg->data = data;

        pr_devel("%s: %s-bit MSI on hwirq %x (xive #%d),"
                 " address=%x_%08x data=%x PE# %d\n",
                 pci_name(dev), is_64 ? "64" : "32", hwirq, xive_num,
                 msg->address_hi, msg->address_lo, data, pe->pe_number);

        return 0;
}

static void pnv_pci_init_ioda_msis(struct pnv_phb *phb)
{
        unsigned int bmap_size;
        const __be32 *prop = of_get_property(phb->hose->dn,
                                             "ibm,opal-msi-ranges", NULL);
        if (!prop) {
                /* BML Fallback */
                prop = of_get_property(phb->hose->dn, "msi-ranges", NULL);
        }
        if (!prop)
                return;

        phb->msi_base = be32_to_cpup(prop);
        phb->msi_count = be32_to_cpup(prop + 1);
        bmap_size = BITS_TO_LONGS(phb->msi_count) * sizeof(unsigned long);
        phb->msi_map = zalloc_maybe_bootmem(bmap_size, GFP_KERNEL);
        if (!phb->msi_map) {
                pr_err("PCI %d: Failed to allocate MSI bitmap !\n",
                       phb->hose->global_number);
                return;
        }
        phb->msi_setup = pnv_pci_ioda_msi_setup;
        phb->msi32_support = 1;
        pr_info("  Allocated bitmap for %d MSIs (base IRQ 0x%x)\n",
                phb->msi_count, phb->msi_base);
}
#else
static void pnv_pci_init_ioda_msis(struct pnv_phb *phb) { }
#endif /* CONFIG_PCI_MSI */

/*
 * This function is supposed to be called on basis of PE from top
 * to bottom style. So the the I/O or MMIO segment assigned to
 * parent PE could be overrided by its child PEs if necessary.
 */
static void __devinit pnv_ioda_setup_pe_seg(struct pci_controller *hose,
                                struct pnv_ioda_pe *pe)
{
        struct pnv_phb *phb = hose->private_data;
        struct pci_bus_region region;
        struct resource *res;
        int i, index;
        int rc;

        /*
         * NOTE: We only care PCI bus based PE for now. For PCI
         * device based PE, for example SRIOV sensitive VF should
         * be figured out later.
         */
        BUG_ON(!(pe->flags & (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL)));

        pci_bus_for_each_resource(pe->pbus, res, i) {
                if (!res || !res->flags ||
                    res->start > res->end)
                        continue;

                if (res->flags & IORESOURCE_IO) {
                        region.start = res->start - phb->ioda.io_pci_base;
                        region.end   = res->end - phb->ioda.io_pci_base;
                        index = region.start / phb->ioda.io_segsize;

                        while (index < phb->ioda.total_pe &&
                               region.start <= region.end) {
                                phb->ioda.io_segmap[index] = pe->pe_number;
                                rc = opal_pci_map_pe_mmio_window(phb->opal_id,
                                        pe->pe_number, OPAL_IO_WINDOW_TYPE, 0, index);
                                if (rc != OPAL_SUCCESS) {
                                        pr_err("%s: OPAL error %d when mapping IO "
                                               "segment #%d to PE#%d\n",
                                               __func__, rc, index, pe->pe_number);
                                        break;
                                }

                                region.start += phb->ioda.io_segsize;
                                index++;
                        }
                } else if (res->flags & IORESOURCE_MEM) {
                        region.start = res->start -
                                       hose->pci_mem_offset -
                                       phb->ioda.m32_pci_base;
                        region.end   = res->end -
                                       hose->pci_mem_offset -
                                       phb->ioda.m32_pci_base;
                        index = region.start / phb->ioda.m32_segsize;

                        while (index < phb->ioda.total_pe &&
                               region.start <= region.end) {
                                phb->ioda.m32_segmap[index] = pe->pe_number;
                                rc = opal_pci_map_pe_mmio_window(phb->opal_id,
                                        pe->pe_number, OPAL_M32_WINDOW_TYPE, 0, index);
                                if (rc != OPAL_SUCCESS) {
                                        pr_err("%s: OPAL error %d when mapping M32 "
                                               "segment#%d to PE#%d",
                                               __func__, rc, index, pe->pe_number);
                                        break;
                                }

                                region.start += phb->ioda.m32_segsize;
                                index++;
                        }
                }
        }
}

static void __devinit pnv_pci_ioda_setup_seg(void)
{
        struct pci_controller *tmp, *hose;
        struct pnv_phb *phb;
        struct pnv_ioda_pe *pe;

        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
                phb = hose->private_data;
                list_for_each_entry(pe, &phb->ioda.pe_list, list) {
                        pnv_ioda_setup_pe_seg(hose, pe);
                }
        }
}

static void __devinit pnv_pci_ioda_setup_DMA(void)
{
        struct pci_controller *hose, *tmp;
        struct pnv_phb *phb;

        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
                pnv_ioda_setup_dma(hose->private_data);

                /* Mark the PHB initialization done */
                phb = hose->private_data;
                phb->initialized = 1;
        }
}

static void __devinit pnv_pci_ioda_fixup(void)
{
        pnv_pci_ioda_setup_PEs();
        pnv_pci_ioda_setup_seg();
        pnv_pci_ioda_setup_DMA();
}

/*
 * Returns the alignment for I/O or memory windows for P2P
 * bridges. That actually depends on how PEs are segmented.
 * For now, we return I/O or M32 segment size for PE sensitive
 * P2P bridges. Otherwise, the default values (4KiB for I/O,
 * 1MiB for memory) will be returned.
 *
 * The current PCI bus might be put into one PE, which was
 * create against the parent PCI bridge. For that case, we
 * needn't enlarge the alignment so that we can save some
 * resources.
 */
static resource_size_t pnv_pci_window_alignment(struct pci_bus *bus,
                                                unsigned long type)
{
        struct pci_dev *bridge;
        struct pci_controller *hose = pci_bus_to_host(bus);
        struct pnv_phb *phb = hose->private_data;
        int num_pci_bridges = 0;

        bridge = bus->self;
        while (bridge) {
                if (pci_pcie_type(bridge) == PCI_EXP_TYPE_PCI_BRIDGE) {
                        num_pci_bridges++;
                        if (num_pci_bridges >= 2)
                                return 1;
                }

                bridge = bridge->bus->self;
        }

        /* We need support prefetchable memory window later */
        if (type & IORESOURCE_MEM)
                return phb->ioda.m32_segsize;

        return phb->ioda.io_segsize;
}

/* Prevent enabling devices for which we couldn't properly
 * assign a PE
 */
static int __devinit pnv_pci_enable_device_hook(struct pci_dev *dev)
{
        struct pci_controller *hose = pci_bus_to_host(dev->bus);
        struct pnv_phb *phb = hose->private_data;
        struct pci_dn *pdn;

        /* The function is probably called while the PEs have
         * not be created yet. For example, resource reassignment
         * during PCI probe period. We just skip the check if
         * PEs isn't ready.
         */
        if (!phb->initialized)
                return 0;

        pdn = pnv_ioda_get_pdn(dev);
        if (!pdn || pdn->pe_number == IODA_INVALID_PE)
                return -EINVAL;

        return 0;
}

static u32 pnv_ioda_bdfn_to_pe(struct pnv_phb *phb, struct pci_bus *bus,
                               u32 devfn)
{
        return phb->ioda.pe_rmap[(bus->number << 8) | devfn];
}

void __init pnv_pci_init_ioda1_phb(struct device_node *np)
{
        struct pci_controller *hose;
        static int primary = 1;
        struct pnv_phb *phb;
        unsigned long size, m32map_off, iomap_off, pemap_off;
        const u64 *prop64;
        u64 phb_id;
        void *aux;
        long rc;

        pr_info(" Initializing IODA OPAL PHB %s\n", np->full_name);

        prop64 = of_get_property(np, "ibm,opal-phbid", NULL);
        if (!prop64) {
                pr_err("  Missing \"ibm,opal-phbid\" property !\n");
                return;
        }
        phb_id = be64_to_cpup(prop64);
        pr_debug("  PHB-ID  : 0x%016llx\n", phb_id);

        phb = alloc_bootmem(sizeof(struct pnv_phb));
        if (phb) {
                memset(phb, 0, sizeof(struct pnv_phb));
                phb->hose = hose = pcibios_alloc_controller(np);
        }
        if (!phb || !phb->hose) {
                pr_err("PCI: Failed to allocate PCI controller for %s\n",
                       np->full_name);
                return;
        }

        spin_lock_init(&phb->lock);
        /* XXX Use device-tree */
        hose->first_busno = 0;
        hose->last_busno = 0xff;
        hose->private_data = phb;
        phb->opal_id = phb_id;
        phb->type = PNV_PHB_IODA1;

        /* Detect specific models for error handling */
        if (of_device_is_compatible(np, "ibm,p7ioc-pciex"))
                phb->model = PNV_PHB_MODEL_P7IOC;
        else
                phb->model = PNV_PHB_MODEL_UNKNOWN;

        /* We parse "ranges" now since we need to deduce the register base
         * from the IO base
         */
        pci_process_bridge_OF_ranges(phb->hose, np, primary);
        primary = 0;

        /* Magic formula from Milton */
        phb->regs = of_iomap(np, 0);
        if (phb->regs == NULL)
                pr_err("  Failed to map registers !\n");


        /* XXX This is hack-a-thon. This needs to be changed so that:
         *  - we obtain stuff like PE# etc... from device-tree
         *  - we properly re-allocate M32 ourselves
         *    (the OFW one isn't very good)
         */

        /* Initialize more IODA stuff */
        phb->ioda.total_pe = 128;

        phb->ioda.m32_size = resource_size(&hose->mem_resources[0]);
        /* OFW Has already off top 64k of M32 space (MSI space) */
        phb->ioda.m32_size += 0x10000;

        phb->ioda.m32_segsize = phb->ioda.m32_size / phb->ioda.total_pe;
        phb->ioda.m32_pci_base = hose->mem_resources[0].start -
                hose->pci_mem_offset;
        phb->ioda.io_size = hose->pci_io_size;
        phb->ioda.io_segsize = phb->ioda.io_size / phb->ioda.total_pe;
        phb->ioda.io_pci_base = 0; /* XXX calculate this ? */

        /* Allocate aux data & arrays */
        size = _ALIGN_UP(phb->ioda.total_pe / 8, sizeof(unsigned long));
        m32map_off = size;
        size += phb->ioda.total_pe * sizeof(phb->ioda.m32_segmap[0]);
        iomap_off = size;
        size += phb->ioda.total_pe * sizeof(phb->ioda.io_segmap[0]);
        pemap_off = size;
        size += phb->ioda.total_pe * sizeof(struct pnv_ioda_pe);
        aux = alloc_bootmem(size);
        memset(aux, 0, size);
        phb->ioda.pe_alloc = aux;
        phb->ioda.m32_segmap = aux + m32map_off;
        phb->ioda.io_segmap = aux + iomap_off;
        phb->ioda.pe_array = aux + pemap_off;
        set_bit(0, phb->ioda.pe_alloc);

        INIT_LIST_HEAD(&phb->ioda.pe_dma_list);
        INIT_LIST_HEAD(&phb->ioda.pe_list);

        /* Calculate how many 32-bit TCE segments we have */
        phb->ioda.tce32_count = phb->ioda.m32_pci_base >> 28;

        /* Clear unusable m64 */
        hose->mem_resources[1].flags = 0;
        hose->mem_resources[1].start = 0;
        hose->mem_resources[1].end = 0;
        hose->mem_resources[2].flags = 0;
        hose->mem_resources[2].start = 0;
        hose->mem_resources[2].end = 0;

#if 0
        rc = opal_pci_set_phb_mem_window(opal->phb_id,
                                         window_type,
                                         window_num,
                                         starting_real_address,
                                         starting_pci_address,
                                         segment_size);
#endif

        pr_info("  %d PE's M32: 0x%x [segment=0x%x] IO: 0x%x [segment=0x%x]\n",
                phb->ioda.total_pe,
                phb->ioda.m32_size, phb->ioda.m32_segsize,
                phb->ioda.io_size, phb->ioda.io_segsize);

        if (phb->regs)  {
                pr_devel(" BUID     = 0x%016llx\n", in_be64(phb->regs + 0x100));
                pr_devel(" PHB2_CR  = 0x%016llx\n", in_be64(phb->regs + 0x160));
                pr_devel(" IO_BAR   = 0x%016llx\n", in_be64(phb->regs + 0x170));
                pr_devel(" IO_BAMR  = 0x%016llx\n", in_be64(phb->regs + 0x178));
                pr_devel(" IO_SAR   = 0x%016llx\n", in_be64(phb->regs + 0x180));
                pr_devel(" M32_BAR  = 0x%016llx\n", in_be64(phb->regs + 0x190));
                pr_devel(" M32_BAMR = 0x%016llx\n", in_be64(phb->regs + 0x198));
                pr_devel(" M32_SAR  = 0x%016llx\n", in_be64(phb->regs + 0x1a0));
        }
        phb->hose->ops = &pnv_pci_ops;

        /* Setup RID -> PE mapping function */
        phb->bdfn_to_pe = pnv_ioda_bdfn_to_pe;

        /* Setup TCEs */
        phb->dma_dev_setup = pnv_pci_ioda_dma_dev_setup;

        /* Setup MSI support */
        pnv_pci_init_ioda_msis(phb);

        /*
         * We pass the PCI probe flag PCI_REASSIGN_ALL_RSRC here
         * to let the PCI core do resource assignment. It's supposed
         * that the PCI core will do correct I/O and MMIO alignment
         * for the P2P bridge bars so that each PCI bus (excluding
         * the child P2P bridges) can form individual PE.
         */
        ppc_md.pcibios_fixup = pnv_pci_ioda_fixup;
        ppc_md.pcibios_enable_device_hook = pnv_pci_enable_device_hook;
        ppc_md.pcibios_window_alignment = pnv_pci_window_alignment;
        pci_add_flags(PCI_REASSIGN_ALL_RSRC);

        /* Reset IODA tables to a clean state */
        rc = opal_pci_reset(phb_id, OPAL_PCI_IODA_TABLE_RESET, OPAL_ASSERT_RESET);
        if (rc)
                pr_warning("  OPAL Error %ld performing IODA table reset !\n", rc);
        opal_pci_set_pe(phb_id, 0, 0, 7, 1, 1 , OPAL_MAP_PE);
}

void __init pnv_pci_init_ioda_hub(struct device_node *np)
{
        struct device_node *phbn;
        const u64 *prop64;
        u64 hub_id;

        pr_info("Probing IODA IO-Hub %s\n", np->full_name);

        prop64 = of_get_property(np, "ibm,opal-hubid", NULL);
        if (!prop64) {
                pr_err(" Missing \"ibm,opal-hubid\" property !\n");
                return;
        }
        hub_id = be64_to_cpup(prop64);
        pr_devel(" HUB-ID : 0x%016llx\n", hub_id);

        /* Count child PHBs */
        for_each_child_of_node(np, phbn) {
                /* Look for IODA1 PHBs */
                if (of_device_is_compatible(phbn, "ibm,ioda-phb"))
                        pnv_pci_init_ioda1_phb(phbn);
        }
}