V4L/DVB (9893): cx18: Convert some list manipulations to emphasize entries not lists

[linux-2.6/linux-2.6-openrd.git] / drivers / acpi / pci_irq.c

/*
 *  pci_irq.c - ACPI PCI Interrupt Routing ($Revision: 11 $)
 *
 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 *  Copyright (C) 2002       Dominik Brodowski <devel@brodo.de>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  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.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */


#include <linux/dmi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/pm.h>
#include <linux/pci.h>
#include <linux/acpi.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

#define _COMPONENT              ACPI_PCI_COMPONENT
ACPI_MODULE_NAME("pci_irq");

static struct acpi_prt_list acpi_prt;
static DEFINE_SPINLOCK(acpi_prt_lock);

/* --------------------------------------------------------------------------
                         PCI IRQ Routing Table (PRT) Support
   -------------------------------------------------------------------------- */

static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(int segment,
                                                          int bus,
                                                          int device, int pin)
{
        struct acpi_prt_entry *entry = NULL;

        if (!acpi_prt.count)
                return NULL;

        /*
         * Parse through all PRT entries looking for a match on the specified
         * PCI device's segment, bus, device, and pin (don't care about func).
         *
         */
        spin_lock(&acpi_prt_lock);
        list_for_each_entry(entry, &acpi_prt.entries, node) {
                if ((segment == entry->id.segment)
                    && (bus == entry->id.bus)
                    && (device == entry->id.device)
                    && (pin == entry->pin)) {
                        spin_unlock(&acpi_prt_lock);
                        return entry;
                }
        }

        spin_unlock(&acpi_prt_lock);
        return NULL;
}

/* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
static struct dmi_system_id medion_md9580[] = {
        {
                .ident = "Medion MD9580-F laptop",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "A555"),
                },
        },
        { }
};

/* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
static struct dmi_system_id dell_optiplex[] = {
        {
                .ident = "Dell Optiplex GX1",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"),
                },
        },
        { }
};

/* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
static struct dmi_system_id hp_t5710[] = {
        {
                .ident = "HP t5710",
                .matches = {
                        DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
                        DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"),
                        DMI_MATCH(DMI_BOARD_NAME, "098Ch"),
                },
        },
        { }
};

struct prt_quirk {
        struct dmi_system_id    *system;
        unsigned int            segment;
        unsigned int            bus;
        unsigned int            device;
        unsigned char           pin;
        char                    *source;        /* according to BIOS */
        char                    *actual_source;
};

/*
 * These systems have incorrect _PRT entries.  The BIOS claims the PCI
 * interrupt at the listed segment/bus/device/pin is connected to the first
 * link device, but it is actually connected to the second.
 */
static struct prt_quirk prt_quirks[] = {
        { medion_md9580, 0, 0, 9, 'A',
                "\\_SB_.PCI0.ISA_.LNKA",
                "\\_SB_.PCI0.ISA_.LNKB"},
        { dell_optiplex, 0, 0, 0xd, 'A',
                "\\_SB_.LNKB",
                "\\_SB_.LNKA"},
        { hp_t5710, 0, 0, 1, 'A',
                "\\_SB_.PCI0.LNK1",
                "\\_SB_.PCI0.LNK3"},
};

static void
do_prt_fixups(struct acpi_prt_entry *entry, struct acpi_pci_routing_table *prt)
{
        int i;
        struct prt_quirk *quirk;

        for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) {
                quirk = &prt_quirks[i];

                /* All current quirks involve link devices, not GSIs */
                if (!prt->source)
                        continue;

                if (dmi_check_system(quirk->system) &&
                    entry->id.segment == quirk->segment &&
                    entry->id.bus == quirk->bus &&
                    entry->id.device == quirk->device &&
                    entry->pin + 'A' == quirk->pin &&
                    !strcmp(prt->source, quirk->source) &&
                    strlen(prt->source) >= strlen(quirk->actual_source)) {
                        printk(KERN_WARNING PREFIX "firmware reports "
                                "%04x:%02x:%02x PCI INT %c connected to %s; "
                                "changing to %s\n",
                                entry->id.segment, entry->id.bus,
                                entry->id.device, 'A' + entry->pin,
                                prt->source, quirk->actual_source);
                        strcpy(prt->source, quirk->actual_source);
                }
        }
}

static int
acpi_pci_irq_add_entry(acpi_handle handle,
                       int segment, int bus, struct acpi_pci_routing_table *prt)
{
        struct acpi_prt_entry *entry = NULL;


        if (!prt)
                return -EINVAL;

        entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
        if (!entry)
                return -ENOMEM;

        entry->id.segment = segment;
        entry->id.bus = bus;
        entry->id.device = (prt->address >> 16) & 0xFFFF;
        entry->id.function = prt->address & 0xFFFF;
        entry->pin = prt->pin;

        do_prt_fixups(entry, prt);

        /*
         * Type 1: Dynamic
         * ---------------
         * The 'source' field specifies the PCI interrupt link device used to
         * configure the IRQ assigned to this slot|dev|pin.  The 'source_index'
         * indicates which resource descriptor in the resource template (of
         * the link device) this interrupt is allocated from.
         * 
         * NOTE: Don't query the Link Device for IRQ information at this time
         *       because Link Device enumeration may not have occurred yet
         *       (e.g. exists somewhere 'below' this _PRT entry in the ACPI
         *       namespace).
         */
        if (prt->source[0]) {
                acpi_get_handle(handle, prt->source, &entry->link.handle);
                entry->link.index = prt->source_index;
        }
        /*
         * Type 2: Static
         * --------------
         * The 'source' field is NULL, and the 'source_index' field specifies
         * the IRQ value, which is hardwired to specific interrupt inputs on
         * the interrupt controller.
         */
        else
                entry->link.index = prt->source_index;

        ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
                              "      %02X:%02X:%02X[%c] -> %s[%d]\n",
                              entry->id.segment, entry->id.bus,
                              entry->id.device, ('A' + entry->pin), prt->source,
                              entry->link.index));

        spin_lock(&acpi_prt_lock);
        list_add_tail(&entry->node, &acpi_prt.entries);
        acpi_prt.count++;
        spin_unlock(&acpi_prt_lock);

        return 0;
}

static void
acpi_pci_irq_del_entry(int segment, int bus, struct acpi_prt_entry *entry)
{
        if (segment == entry->id.segment && bus == entry->id.bus) {
                acpi_prt.count--;
                list_del(&entry->node);
                kfree(entry);
        }
}

int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
{
        acpi_status status = AE_OK;
        char *pathname = NULL;
        struct acpi_buffer buffer = { 0, NULL };
        struct acpi_pci_routing_table *prt = NULL;
        struct acpi_pci_routing_table *entry = NULL;
        static int first_time = 1;


        pathname = kzalloc(ACPI_PATHNAME_MAX, GFP_KERNEL);
        if (!pathname)
                return -ENOMEM;

        if (first_time) {
                acpi_prt.count = 0;
                INIT_LIST_HEAD(&acpi_prt.entries);
                first_time = 0;
        }

        /* 
         * NOTE: We're given a 'handle' to the _PRT object's parent device
         *       (either a PCI root bridge or PCI-PCI bridge).
         */

        buffer.length = ACPI_PATHNAME_MAX;
        buffer.pointer = pathname;
        acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);

        printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
               pathname);

        /* 
         * Evaluate this _PRT and add its entries to our global list (acpi_prt).
         */

        buffer.length = 0;
        buffer.pointer = NULL;
        kfree(pathname);
        status = acpi_get_irq_routing_table(handle, &buffer);
        if (status != AE_BUFFER_OVERFLOW) {
                ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]",
                                acpi_format_exception(status)));
                return -ENODEV;
        }

        prt = kzalloc(buffer.length, GFP_KERNEL);
        if (!prt) {
                return -ENOMEM;
        }
        buffer.pointer = prt;

        status = acpi_get_irq_routing_table(handle, &buffer);
        if (ACPI_FAILURE(status)) {
                ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]",
                                acpi_format_exception(status)));
                kfree(buffer.pointer);
                return -ENODEV;
        }

        entry = prt;

        while (entry && (entry->length > 0)) {
                acpi_pci_irq_add_entry(handle, segment, bus, entry);
                entry = (struct acpi_pci_routing_table *)
                    ((unsigned long)entry + entry->length);
        }

        kfree(prt);

        return 0;
}

void acpi_pci_irq_del_prt(int segment, int bus)
{
        struct list_head *node = NULL, *n = NULL;
        struct acpi_prt_entry *entry = NULL;

        if (!acpi_prt.count) {
                return;
        }

        printk(KERN_DEBUG
               "ACPI: Delete PCI Interrupt Routing Table for %x:%x\n", segment,
               bus);
        spin_lock(&acpi_prt_lock);
        list_for_each_safe(node, n, &acpi_prt.entries) {
                entry = list_entry(node, struct acpi_prt_entry, node);

                acpi_pci_irq_del_entry(segment, bus, entry);
        }
        spin_unlock(&acpi_prt_lock);
}

/* --------------------------------------------------------------------------
                          PCI Interrupt Routing Support
   -------------------------------------------------------------------------- */
typedef int (*irq_lookup_func) (struct acpi_prt_entry *, int *, int *, char **);

static int
acpi_pci_allocate_irq(struct acpi_prt_entry *entry,
                      int *triggering, int *polarity, char **link)
{
        int irq;


        if (entry->link.handle) {
                irq = acpi_pci_link_allocate_irq(entry->link.handle,
                                                 entry->link.index, triggering,
                                                 polarity, link);
                if (irq < 0) {
                        printk(KERN_WARNING PREFIX
                                      "Invalid IRQ link routing entry\n");
                        return -1;
                }
        } else {
                irq = entry->link.index;
                *triggering = ACPI_LEVEL_SENSITIVE;
                *polarity = ACPI_ACTIVE_LOW;
        }

        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found IRQ %d\n", irq));
        return irq;
}

static int
acpi_pci_free_irq(struct acpi_prt_entry *entry,
                  int *triggering, int *polarity, char **link)
{
        int irq;

        if (entry->link.handle) {
                irq = acpi_pci_link_free_irq(entry->link.handle);
        } else {
                irq = entry->link.index;
        }
        return irq;
}

#ifdef CONFIG_X86_IO_APIC
extern int noioapicquirk;

static int bridge_has_boot_interrupt_variant(struct pci_bus *bus)
{
        struct pci_bus *bus_it;

        for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) {
                if (!bus_it->self)
                        return 0;

                printk(KERN_INFO "vendor=%04x device=%04x\n", bus_it->self->vendor,
                                bus_it->self->device);

                if (bus_it->self->irq_reroute_variant)
                        return bus_it->self->irq_reroute_variant;
        }
        return 0;
}
#endif /* CONFIG_X86_IO_APIC */

/*
 * acpi_pci_irq_lookup
 * success: return IRQ >= 0
 * failure: return -1
 */
static int
acpi_pci_irq_lookup(struct pci_bus *bus,
                    int device,
                    int pin,
                    int *triggering,
                    int *polarity, char **link, irq_lookup_func func)
{
        struct acpi_prt_entry *entry = NULL;
        int segment = pci_domain_nr(bus);
        int bus_nr = bus->number;
        int ret;


        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                          "Searching for PRT entry for %02x:%02x:%02x[%c]\n",
                          segment, bus_nr, device, ('A' + pin)));

        entry = acpi_pci_irq_find_prt_entry(segment, bus_nr, device, pin);
        if (!entry) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PRT entry not found\n"));
                return -1;
        }

        ret = func(entry, triggering, polarity, link);

#ifdef CONFIG_X86_IO_APIC
        /*
         * Some chipsets (e.g. intel 6700PXH) generate a legacy INTx when the
         * IRQ entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel
         * does during interrupt handling). When this INTx generation cannot be
         * disabled, we reroute these interrupts to their legacy equivalent to
         * get rid of spurious interrupts.
         */
        if (!noioapicquirk) {
                switch (bridge_has_boot_interrupt_variant(bus)) {
                case 0:
                        /* no rerouting necessary */
                        break;

                case INTEL_IRQ_REROUTE_VARIANT:
                        /*
                         * Remap according to INTx routing table in 6700PXH
                         * specs, intel order number 302628-002, section
                         * 2.15.2. Other chipsets (80332, ...) have the same
                         * mapping and are handled here as well.
                         */
                        printk(KERN_INFO "pci irq %d -> rerouted to legacy "
                                         "irq %d\n", ret, (ret % 4) + 16);
                        ret = (ret % 4) + 16;
                        break;

                default:
                        printk(KERN_INFO "not rerouting irq %d to legacy irq: "
                                         "unknown mapping\n", ret);
                        break;
                }
        }
#endif /* CONFIG_X86_IO_APIC */

        return ret;
}

/*
 * acpi_pci_irq_derive
 * success: return IRQ >= 0
 * failure: return < 0
 */
static int
acpi_pci_irq_derive(struct pci_dev *dev,
                    int pin,
                    int *triggering,
                    int *polarity, char **link, irq_lookup_func func)
{
        struct pci_dev *bridge = dev;
        int irq = -1;
        u8 bridge_pin = 0, orig_pin = pin;


        if (!dev)
                return -EINVAL;

        /* 
         * Attempt to derive an IRQ for this device from a parent bridge's
         * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
         */
        while (irq < 0 && bridge->bus->self) {
                pin = (pin + PCI_SLOT(bridge->devfn)) % 4;
                bridge = bridge->bus->self;

                if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
                        /* PC card has the same IRQ as its cardbridge */
                        bridge_pin = bridge->pin;
                        if (!bridge_pin) {
                                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                                  "No interrupt pin configured for device %s\n",
                                                  pci_name(bridge)));
                                return -1;
                        }
                        /* Pin is from 0 to 3 */
                        bridge_pin--;
                        pin = bridge_pin;
                }

                irq = acpi_pci_irq_lookup(bridge->bus, PCI_SLOT(bridge->devfn),
                                          pin, triggering, polarity,
                                          link, func);
        }

        if (irq < 0) {
                dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
                         'A' + orig_pin);
                return -1;
        }

        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Derive IRQ %d for device %s from %s\n",
                          irq, pci_name(dev), pci_name(bridge)));

        return irq;
}

/*
 * acpi_pci_irq_enable
 * success: return 0
 * failure: return < 0
 */

int acpi_pci_irq_enable(struct pci_dev *dev)
{
        int irq = 0;
        u8 pin = 0;
        int triggering = ACPI_LEVEL_SENSITIVE;
        int polarity = ACPI_ACTIVE_LOW;
        char *link = NULL;
        char link_desc[16];
        int rc;


        if (!dev)
                return -EINVAL;

        pin = dev->pin;
        if (!pin) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                  "No interrupt pin configured for device %s\n",
                                  pci_name(dev)));
                return 0;
        }
        pin--;

        if (!dev->bus) {
                dev_err(&dev->dev, "invalid (NULL) 'bus' field\n");
                return -ENODEV;
        }

        /* 
         * First we check the PCI IRQ routing table (PRT) for an IRQ.  PRT
         * values override any BIOS-assigned IRQs set during boot.
         */
        irq = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
                                  &triggering, &polarity, &link,
                                  acpi_pci_allocate_irq);

        /*
         * If no PRT entry was found, we'll try to derive an IRQ from the
         * device's parent bridge.
         */
        if (irq < 0)
                irq = acpi_pci_irq_derive(dev, pin, &triggering,
                                          &polarity, &link,
                                          acpi_pci_allocate_irq);

        if (irq < 0) {
                /*
                 * IDE legacy mode controller IRQs are magic. Why do compat
                 * extensions always make such a nasty mess.
                 */
                if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
                                (dev->class & 0x05) == 0)
                        return 0;
        }
        /*
         * No IRQ known to the ACPI subsystem - maybe the BIOS / 
         * driver reported one, then use it. Exit in any case.
         */
        if (irq < 0) {
                dev_warn(&dev->dev, "PCI INT %c: no GSI", 'A' + pin);
                /* Interrupt Line values above 0xF are forbidden */
                if (dev->irq > 0 && (dev->irq <= 0xF)) {
                        printk(" - using IRQ %d\n", dev->irq);
                        acpi_register_gsi(dev->irq, ACPI_LEVEL_SENSITIVE,
                                          ACPI_ACTIVE_LOW);
                        return 0;
                } else {
                        printk("\n");
                        return 0;
                }
        }

        rc = acpi_register_gsi(irq, triggering, polarity);
        if (rc < 0) {
                dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
                         'A' + pin);
                return rc;
        }
        dev->irq = rc;

        if (link)
                snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
        else
                link_desc[0] = '\0';

        dev_info(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
                 'A' + pin, link_desc, irq,
                 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
                 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);

        return 0;
}

/* FIXME: implement x86/x86_64 version */
void __attribute__ ((weak)) acpi_unregister_gsi(u32 i)
{
}

void acpi_pci_irq_disable(struct pci_dev *dev)
{
        int gsi = 0;
        u8 pin = 0;
        int triggering = ACPI_LEVEL_SENSITIVE;
        int polarity = ACPI_ACTIVE_LOW;


        if (!dev || !dev->bus)
                return;

        pin = dev->pin;
        if (!pin)
                return;
        pin--;

        /*
         * First we check the PCI IRQ routing table (PRT) for an IRQ.
         */
        gsi = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
                                  &triggering, &polarity, NULL,
                                  acpi_pci_free_irq);
        /*
         * If no PRT entry was found, we'll try to derive an IRQ from the
         * device's parent bridge.
         */
        if (gsi < 0)
                gsi = acpi_pci_irq_derive(dev, pin,
                                          &triggering, &polarity, NULL,
                                          acpi_pci_free_irq);
        if (gsi < 0)
                return;

        /*
         * TBD: It might be worth clearing dev->irq by magic constant
         * (e.g. PCI_UNDEFINED_IRQ).
         */

        dev_info(&dev->dev, "PCI INT %c disabled\n", 'A' + pin);
        acpi_unregister_gsi(gsi);
}