/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1992 - 1997, 2000-2006 Silicon Graphics, Inc. All rights reserved.
 */

#include <linux/slab.h>
#include <linux/export.h>
#include <asm/sn/types.h>
#include <asm/sn/addrs.h>
#include <asm/sn/io.h>
#include <asm/sn/module.h>
#include <asm/sn/intr.h>
#include <asm/sn/pcibus_provider_defs.h>
#include <asm/sn/pcidev.h>
#include <asm/sn/sn_sal.h>
#include "xtalk/hubdev.h"

/*
 * The code in this file will only be executed when running with
 * a PROM that does _not_ have base ACPI IO support.
 * (i.e., SN_ACPI_BASE_SUPPORT() == 0)
 */

static int max_segment_number;           /* Default highest segment number */
static int max_pcibus_number = 255;     /* Default highest pci bus number */


/*
 * Retrieve the hub device info structure for the given nasid.
 */
static inline u64 sal_get_hubdev_info(u64 handle, u64 address)
{
        struct ia64_sal_retval ret_stuff;
        ret_stuff.status = 0;
        ret_stuff.v0 = 0;

        SAL_CALL_NOLOCK(ret_stuff,
                        (u64) SN_SAL_IOIF_GET_HUBDEV_INFO,
                        (u64) handle, (u64) address, 0, 0, 0, 0, 0);
        return ret_stuff.v0;
}

/*
 * Retrieve the pci bus information given the bus number.
 */
static inline u64 sal_get_pcibus_info(u64 segment, u64 busnum, u64 address)
{
        struct ia64_sal_retval ret_stuff;
        ret_stuff.status = 0;
        ret_stuff.v0 = 0;

        SAL_CALL_NOLOCK(ret_stuff,
                        (u64) SN_SAL_IOIF_GET_PCIBUS_INFO,
                        (u64) segment, (u64) busnum, (u64) address, 0, 0, 0, 0);
        return ret_stuff.v0;
}

/*
 * Retrieve the pci device information given the bus and device|function number.
 */
static inline u64
sal_get_pcidev_info(u64 segment, u64 bus_number, u64 devfn, u64 pci_dev,
                    u64 sn_irq_info)
{
        struct ia64_sal_retval ret_stuff;
        ret_stuff.status = 0;
        ret_stuff.v0 = 0;

        SAL_CALL_NOLOCK(ret_stuff,
                        (u64) SN_SAL_IOIF_GET_PCIDEV_INFO,
                        (u64) segment, (u64) bus_number, (u64) devfn,
                        (u64) pci_dev,
                        sn_irq_info, 0, 0);
        return ret_stuff.v0;
}


/*
 * sn_fixup_ionodes() - This routine initializes the HUB data structure for
 *                      each node in the system. This function is only
 *                      executed when running with a non-ACPI capable PROM.
 */
static void __init sn_fixup_ionodes(void)
{

        struct hubdev_info *hubdev;
        u64 status;
        u64 nasid;
        int i;
        extern void sn_common_hubdev_init(struct hubdev_info *);

        /*
         * Get SGI Specific HUB chipset information.
         * Inform Prom that this kernel can support domain bus numbering.
         */
        for (i = 0; i < num_cnodes; i++) {
                hubdev = (struct hubdev_info *)(NODEPDA(i)->pdinfo);
                nasid = cnodeid_to_nasid(i);
                hubdev->max_segment_number = 0xffffffff;
                hubdev->max_pcibus_number = 0xff;
                status = sal_get_hubdev_info(nasid, (u64) __pa(hubdev));
                if (status)
                        continue;

                /* Save the largest Domain and pcibus numbers found. */
                if (hubdev->max_segment_number) {
                        /*
                         * Dealing with a Prom that supports segments.
                         */
                        max_segment_number = hubdev->max_segment_number;
                        max_pcibus_number = hubdev->max_pcibus_number;
                }
                sn_common_hubdev_init(hubdev);
        }
}

/*
 * sn_pci_legacy_window_fixup - Setup PCI resources for
 *                              legacy IO and MEM space. This needs to
 *                              be done here, as the PROM does not have
 *                              ACPI support defining the root buses
 *                              and their resources (_CRS),
 */
static void
sn_legacy_pci_window_fixup(struct resource *res,
                u64 legacy_io, u64 legacy_mem)
{
                res[0].name = "legacy_io";
                res[0].flags = IORESOURCE_IO;
                res[0].start = legacy_io;
                res[0].end = res[0].start + 0xffff;
                res[0].parent = &ioport_resource;
                res[1].name = "legacy_mem";
                res[1].flags = IORESOURCE_MEM;
                res[1].start = legacy_mem;
                res[1].end = res[1].start + (1024 * 1024) - 1;
                res[1].parent = &iomem_resource;
}

/*
 * sn_io_slot_fixup() -   We are not running with an ACPI capable PROM,
 *                        and need to convert the pci_dev->resource
 *                        'start' and 'end' addresses to mapped addresses,
 *                        and setup the pci_controller->window array entries.
 */
void
sn_io_slot_fixup(struct pci_dev *dev)
{
        int idx;
        struct resource *res;
        unsigned long size;
        struct pcidev_info *pcidev_info;
        struct sn_irq_info *sn_irq_info;
        int status;

        pcidev_info = kzalloc(sizeof(struct pcidev_info), GFP_KERNEL);
        if (!pcidev_info)
                panic("%s: Unable to alloc memory for pcidev_info", __func__);

        sn_irq_info = kzalloc(sizeof(struct sn_irq_info), GFP_KERNEL);
        if (!sn_irq_info)
                panic("%s: Unable to alloc memory for sn_irq_info", __func__);

        /* Call to retrieve pci device information needed by kernel. */
        status = sal_get_pcidev_info((u64) pci_domain_nr(dev),
                (u64) dev->bus->number,
                dev->devfn,
                (u64) __pa(pcidev_info),
                (u64) __pa(sn_irq_info));

        BUG_ON(status); /* Cannot get platform pci device information */


        /* Copy over PIO Mapped Addresses */
        for (idx = 0; idx <= PCI_ROM_RESOURCE; idx++) {
                if (!pcidev_info->pdi_pio_mapped_addr[idx])
                        continue;

                res = &dev->resource[idx];

                size = res->end - res->start;
                if (size == 0)
                        continue;

                res->start = pcidev_info->pdi_pio_mapped_addr[idx];
                res->end = res->start + size;

                /*
                 * if it's already in the device structure, remove it before
                 * inserting
                 */
                if (res->parent && res->parent->child)
                        release_resource(res);

                if (res->flags & IORESOURCE_IO)
                        insert_resource(&ioport_resource, res);
                else
                        insert_resource(&iomem_resource, res);
                /*
                 * If ROM, mark as shadowed in PROM.
                 */
                if (idx == PCI_ROM_RESOURCE) {
                        pci_disable_rom(dev);
                        res->flags = IORESOURCE_MEM | IORESOURCE_ROM_SHADOW |
                                     IORESOURCE_PCI_FIXED;
                }
        }

        sn_pci_fixup_slot(dev, pcidev_info, sn_irq_info);
}
EXPORT_SYMBOL(sn_io_slot_fixup);

/*
 * sn_pci_controller_fixup() - This routine sets up a bus's resources
 *                             consistent with the Linux PCI abstraction layer.
 */
static void __init
sn_pci_controller_fixup(int segment, int busnum, struct pci_bus *bus)
{
        s64 status = 0;
        struct pci_controller *controller;
        struct pcibus_bussoft *prom_bussoft_ptr;
        struct resource *res;
        LIST_HEAD(resources);

        status = sal_get_pcibus_info((u64) segment, (u64) busnum,
                                     (u64) ia64_tpa(&prom_bussoft_ptr));
        if (status > 0)
                return;         /*bus # does not exist */
        prom_bussoft_ptr = __va(prom_bussoft_ptr);

        controller = kzalloc(sizeof(*controller), GFP_KERNEL);
        BUG_ON(!controller);
        controller->segment = segment;

        res = kcalloc(2, sizeof(struct resource), GFP_KERNEL);
        BUG_ON(!res);

        /*
         * Temporarily save the prom_bussoft_ptr for use by sn_bus_fixup().
         * (platform_data will be overwritten later in sn_common_bus_fixup())
         */
        controller->platform_data = prom_bussoft_ptr;

        sn_legacy_pci_window_fixup(res,
                        prom_bussoft_ptr->bs_legacy_io,
                        prom_bussoft_ptr->bs_legacy_mem);
        pci_add_resource_offset(&resources,     &res[0],
                        prom_bussoft_ptr->bs_legacy_io);
        pci_add_resource_offset(&resources,     &res[1],
                        prom_bussoft_ptr->bs_legacy_mem);

        bus = pci_scan_root_bus(NULL, busnum, &pci_root_ops, controller,
                                &resources);
        if (bus == NULL) {
                kfree(res);
                kfree(controller);
                return;
        }
        pci_bus_add_devices(bus);
}

/*
 * sn_bus_fixup
 */
void
sn_bus_fixup(struct pci_bus *bus)
{
        struct pci_dev *pci_dev = NULL;
        struct pcibus_bussoft *prom_bussoft_ptr;

        if (!bus->parent) {  /* If root bus */
                prom_bussoft_ptr = PCI_CONTROLLER(bus)->platform_data;
                if (prom_bussoft_ptr == NULL) {
                        printk(KERN_ERR
                               "sn_bus_fixup: 0x%04x:0x%02x Unable to "
                               "obtain prom_bussoft_ptr\n",
                               pci_domain_nr(bus), bus->number);
                        return;
                }
                sn_common_bus_fixup(bus, prom_bussoft_ptr);
        }
        list_for_each_entry(pci_dev, &bus->devices, bus_list) {
                sn_io_slot_fixup(pci_dev);
        }

}

/*
 * sn_io_init - PROM does not have ACPI support to define nodes or root buses,
 *              so we need to do things the hard way, including initiating the
 *              bus scanning ourselves.
 */

void __init sn_io_init(void)
{
        int i, j;

        sn_fixup_ionodes();

        /* busses are not known yet ... */
        for (i = 0; i <= max_segment_number; i++)
                for (j = 0; j <= max_pcibus_number; j++)
                        sn_pci_controller_fixup(i, j, NULL);
}