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Diffstat (limited to 'drivers/acpi/pci_link.c')
-rw-r--r--drivers/acpi/pci_link.c969
1 files changed, 969 insertions, 0 deletions
diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c
new file mode 100644
index 0000000..e33c0bc
--- /dev/null
+++ b/drivers/acpi/pci_link.c
@@ -0,0 +1,969 @@
+/*
+ * pci_link.c - ACPI PCI Interrupt Link Device Driver ($Revision: 34 $)
+ *
+ * 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.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * TBD:
+ * 1. Support more than one IRQ resource entry per link device (index).
+ * 2. Implement start/stop mechanism and use ACPI Bus Driver facilities
+ * for IRQ management (e.g. start()->_SRS).
+ */
+
+#include <linux/sysdev.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/mutex.h>
+
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+
+#define _COMPONENT ACPI_PCI_COMPONENT
+ACPI_MODULE_NAME("pci_link");
+#define ACPI_PCI_LINK_CLASS "pci_irq_routing"
+#define ACPI_PCI_LINK_DEVICE_NAME "PCI Interrupt Link"
+#define ACPI_PCI_LINK_FILE_INFO "info"
+#define ACPI_PCI_LINK_FILE_STATUS "state"
+#define ACPI_PCI_LINK_MAX_POSSIBLE 16
+static int acpi_pci_link_add(struct acpi_device *device);
+static int acpi_pci_link_remove(struct acpi_device *device, int type);
+
+static struct acpi_device_id link_device_ids[] = {
+ {"PNP0C0F", 0},
+ {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, link_device_ids);
+
+static struct acpi_driver acpi_pci_link_driver = {
+ .name = "pci_link",
+ .class = ACPI_PCI_LINK_CLASS,
+ .ids = link_device_ids,
+ .ops = {
+ .add = acpi_pci_link_add,
+ .remove = acpi_pci_link_remove,
+ },
+};
+
+/*
+ * If a link is initialized, we never change its active and initialized
+ * later even the link is disable. Instead, we just repick the active irq
+ */
+struct acpi_pci_link_irq {
+ u8 active; /* Current IRQ */
+ u8 triggering; /* All IRQs */
+ u8 polarity; /* All IRQs */
+ u8 resource_type;
+ u8 possible_count;
+ u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
+ u8 initialized:1;
+ u8 reserved:7;
+};
+
+struct acpi_pci_link {
+ struct list_head node;
+ struct acpi_device *device;
+ struct acpi_pci_link_irq irq;
+ int refcnt;
+};
+
+static struct {
+ int count;
+ struct list_head entries;
+} acpi_link;
+static DEFINE_MUTEX(acpi_link_lock);
+
+/* --------------------------------------------------------------------------
+ PCI Link Device Management
+ -------------------------------------------------------------------------- */
+
+/*
+ * set context (link) possible list from resource list
+ */
+static acpi_status
+acpi_pci_link_check_possible(struct acpi_resource *resource, void *context)
+{
+ struct acpi_pci_link *link = context;
+ u32 i = 0;
+
+
+ switch (resource->type) {
+ case ACPI_RESOURCE_TYPE_START_DEPENDENT:
+ case ACPI_RESOURCE_TYPE_END_TAG:
+ return AE_OK;
+ case ACPI_RESOURCE_TYPE_IRQ:
+ {
+ struct acpi_resource_irq *p = &resource->data.irq;
+ if (!p || !p->interrupt_count) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Blank _PRS IRQ resource\n"));
+ return AE_OK;
+ }
+ for (i = 0;
+ (i < p->interrupt_count
+ && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
+ if (!p->interrupts[i]) {
+ printk(KERN_WARNING PREFIX
+ "Invalid _PRS IRQ %d\n",
+ p->interrupts[i]);
+ continue;
+ }
+ link->irq.possible[i] = p->interrupts[i];
+ link->irq.possible_count++;
+ }
+ link->irq.triggering = p->triggering;
+ link->irq.polarity = p->polarity;
+ link->irq.resource_type = ACPI_RESOURCE_TYPE_IRQ;
+ break;
+ }
+ case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+ {
+ struct acpi_resource_extended_irq *p =
+ &resource->data.extended_irq;
+ if (!p || !p->interrupt_count) {
+ printk(KERN_WARNING PREFIX
+ "Blank _PRS EXT IRQ resource\n");
+ return AE_OK;
+ }
+ for (i = 0;
+ (i < p->interrupt_count
+ && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
+ if (!p->interrupts[i]) {
+ printk(KERN_WARNING PREFIX
+ "Invalid _PRS IRQ %d\n",
+ p->interrupts[i]);
+ continue;
+ }
+ link->irq.possible[i] = p->interrupts[i];
+ link->irq.possible_count++;
+ }
+ link->irq.triggering = p->triggering;
+ link->irq.polarity = p->polarity;
+ link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
+ break;
+ }
+ default:
+ printk(KERN_ERR PREFIX "_PRS resource type 0x%x isn't an IRQ\n",
+ resource->type);
+ return AE_OK;
+ }
+
+ return AE_CTRL_TERMINATE;
+}
+
+static int acpi_pci_link_get_possible(struct acpi_pci_link *link)
+{
+ acpi_status status;
+
+
+ if (!link)
+ return -EINVAL;
+
+ status = acpi_walk_resources(link->device->handle, METHOD_NAME__PRS,
+ acpi_pci_link_check_possible, link);
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRS"));
+ return -ENODEV;
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Found %d possible IRQs\n",
+ link->irq.possible_count));
+
+ return 0;
+}
+
+static acpi_status
+acpi_pci_link_check_current(struct acpi_resource *resource, void *context)
+{
+ int *irq = (int *)context;
+
+
+ switch (resource->type) {
+ case ACPI_RESOURCE_TYPE_START_DEPENDENT:
+ case ACPI_RESOURCE_TYPE_END_TAG:
+ return AE_OK;
+ case ACPI_RESOURCE_TYPE_IRQ:
+ {
+ struct acpi_resource_irq *p = &resource->data.irq;
+ if (!p || !p->interrupt_count) {
+ /*
+ * IRQ descriptors may have no IRQ# bits set,
+ * particularly those those w/ _STA disabled
+ */
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Blank _CRS IRQ resource\n"));
+ return AE_OK;
+ }
+ *irq = p->interrupts[0];
+ break;
+ }
+ case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+ {
+ struct acpi_resource_extended_irq *p =
+ &resource->data.extended_irq;
+ if (!p || !p->interrupt_count) {
+ /*
+ * extended IRQ descriptors must
+ * return at least 1 IRQ
+ */
+ printk(KERN_WARNING PREFIX
+ "Blank _CRS EXT IRQ resource\n");
+ return AE_OK;
+ }
+ *irq = p->interrupts[0];
+ break;
+ }
+ break;
+ default:
+ printk(KERN_ERR PREFIX "_CRS resource type 0x%x isn't an IRQ\n",
+ resource->type);
+ return AE_OK;
+ }
+
+ return AE_CTRL_TERMINATE;
+}
+
+/*
+ * Run _CRS and set link->irq.active
+ *
+ * return value:
+ * 0 - success
+ * !0 - failure
+ */
+static int acpi_pci_link_get_current(struct acpi_pci_link *link)
+{
+ int result = 0;
+ acpi_status status = AE_OK;
+ int irq = 0;
+
+ if (!link)
+ return -EINVAL;
+
+ link->irq.active = 0;
+
+ /* in practice, status disabled is meaningless, ignore it */
+ if (acpi_strict) {
+ /* Query _STA, set link->device->status */
+ result = acpi_bus_get_status(link->device);
+ if (result) {
+ printk(KERN_ERR PREFIX "Unable to read status\n");
+ goto end;
+ }
+
+ if (!link->device->status.enabled) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
+ return 0;
+ }
+ }
+
+ /*
+ * Query and parse _CRS to get the current IRQ assignment.
+ */
+
+ status = acpi_walk_resources(link->device->handle, METHOD_NAME__CRS,
+ acpi_pci_link_check_current, &irq);
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _CRS"));
+ result = -ENODEV;
+ goto end;
+ }
+
+ if (acpi_strict && !irq) {
+ printk(KERN_ERR PREFIX "_CRS returned 0\n");
+ result = -ENODEV;
+ }
+
+ link->irq.active = irq;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
+
+ end:
+ return result;
+}
+
+static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
+{
+ int result = 0;
+ acpi_status status = AE_OK;
+ struct {
+ struct acpi_resource res;
+ struct acpi_resource end;
+ } *resource;
+ struct acpi_buffer buffer = { 0, NULL };
+
+
+ if (!link || !irq)
+ return -EINVAL;
+
+ resource = kzalloc(sizeof(*resource) + 1, irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
+ if (!resource)
+ return -ENOMEM;
+
+ buffer.length = sizeof(*resource) + 1;
+ buffer.pointer = resource;
+
+ switch (link->irq.resource_type) {
+ case ACPI_RESOURCE_TYPE_IRQ:
+ resource->res.type = ACPI_RESOURCE_TYPE_IRQ;
+ resource->res.length = sizeof(struct acpi_resource);
+ resource->res.data.irq.triggering = link->irq.triggering;
+ resource->res.data.irq.polarity =
+ link->irq.polarity;
+ if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
+ resource->res.data.irq.sharable =
+ ACPI_EXCLUSIVE;
+ else
+ resource->res.data.irq.sharable = ACPI_SHARED;
+ resource->res.data.irq.interrupt_count = 1;
+ resource->res.data.irq.interrupts[0] = irq;
+ break;
+
+ case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+ resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
+ resource->res.length = sizeof(struct acpi_resource);
+ resource->res.data.extended_irq.producer_consumer =
+ ACPI_CONSUMER;
+ resource->res.data.extended_irq.triggering =
+ link->irq.triggering;
+ resource->res.data.extended_irq.polarity =
+ link->irq.polarity;
+ if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
+ resource->res.data.irq.sharable =
+ ACPI_EXCLUSIVE;
+ else
+ resource->res.data.irq.sharable = ACPI_SHARED;
+ resource->res.data.extended_irq.interrupt_count = 1;
+ resource->res.data.extended_irq.interrupts[0] = irq;
+ /* ignore resource_source, it's optional */
+ break;
+ default:
+ printk(KERN_ERR PREFIX "Invalid Resource_type %d\n", link->irq.resource_type);
+ result = -EINVAL;
+ goto end;
+
+ }
+ resource->end.type = ACPI_RESOURCE_TYPE_END_TAG;
+
+ /* Attempt to set the resource */
+ status = acpi_set_current_resources(link->device->handle, &buffer);
+
+ /* check for total failure */
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS"));
+ result = -ENODEV;
+ goto end;
+ }
+
+ /* Query _STA, set device->status */
+ result = acpi_bus_get_status(link->device);
+ if (result) {
+ printk(KERN_ERR PREFIX "Unable to read status\n");
+ goto end;
+ }
+ if (!link->device->status.enabled) {
+ printk(KERN_WARNING PREFIX
+ "%s [%s] disabled and referenced, BIOS bug\n",
+ acpi_device_name(link->device),
+ acpi_device_bid(link->device));
+ }
+
+ /* Query _CRS, set link->irq.active */
+ result = acpi_pci_link_get_current(link);
+ if (result) {
+ goto end;
+ }
+
+ /*
+ * Is current setting not what we set?
+ * set link->irq.active
+ */
+ if (link->irq.active != irq) {
+ /*
+ * policy: when _CRS doesn't return what we just _SRS
+ * assume _SRS worked and override _CRS value.
+ */
+ printk(KERN_WARNING PREFIX
+ "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
+ acpi_device_name(link->device),
+ acpi_device_bid(link->device), link->irq.active, irq);
+ link->irq.active = irq;
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
+
+ end:
+ kfree(resource);
+ return result;
+}
+
+/* --------------------------------------------------------------------------
+ PCI Link IRQ Management
+ -------------------------------------------------------------------------- */
+
+/*
+ * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
+ * Link Devices to move the PIRQs around to minimize sharing.
+ *
+ * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
+ * that the BIOS has already set to active. This is necessary because
+ * ACPI has no automatic means of knowing what ISA IRQs are used. Note that
+ * if the BIOS doesn't set a Link Device active, ACPI needs to program it
+ * even if acpi_irq_nobalance is set.
+ *
+ * A tables of penalties avoids directing PCI interrupts to well known
+ * ISA IRQs. Boot params are available to over-ride the default table:
+ *
+ * List interrupts that are free for PCI use.
+ * acpi_irq_pci=n[,m]
+ *
+ * List interrupts that should not be used for PCI:
+ * acpi_irq_isa=n[,m]
+ *
+ * Note that PCI IRQ routers have a list of possible IRQs,
+ * which may not include the IRQs this table says are available.
+ *
+ * Since this heuristic can't tell the difference between a link
+ * that no device will attach to, vs. a link which may be shared
+ * by multiple active devices -- it is not optimal.
+ *
+ * If interrupt performance is that important, get an IO-APIC system
+ * with a pin dedicated to each device. Or for that matter, an MSI
+ * enabled system.
+ */
+
+#define ACPI_MAX_IRQS 256
+#define ACPI_MAX_ISA_IRQ 16
+
+#define PIRQ_PENALTY_PCI_AVAILABLE (0)
+#define PIRQ_PENALTY_PCI_POSSIBLE (16*16)
+#define PIRQ_PENALTY_PCI_USING (16*16*16)
+#define PIRQ_PENALTY_ISA_TYPICAL (16*16*16*16)
+#define PIRQ_PENALTY_ISA_USED (16*16*16*16*16)
+#define PIRQ_PENALTY_ISA_ALWAYS (16*16*16*16*16*16)
+
+static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
+ PIRQ_PENALTY_ISA_ALWAYS, /* IRQ0 timer */
+ PIRQ_PENALTY_ISA_ALWAYS, /* IRQ1 keyboard */
+ PIRQ_PENALTY_ISA_ALWAYS, /* IRQ2 cascade */
+ PIRQ_PENALTY_ISA_TYPICAL, /* IRQ3 serial */
+ PIRQ_PENALTY_ISA_TYPICAL, /* IRQ4 serial */
+ PIRQ_PENALTY_ISA_TYPICAL, /* IRQ5 sometimes SoundBlaster */
+ PIRQ_PENALTY_ISA_TYPICAL, /* IRQ6 */
+ PIRQ_PENALTY_ISA_TYPICAL, /* IRQ7 parallel, spurious */
+ PIRQ_PENALTY_ISA_TYPICAL, /* IRQ8 rtc, sometimes */
+ PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ9 PCI, often acpi */
+ PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ10 PCI */
+ PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ11 PCI */
+ PIRQ_PENALTY_ISA_USED, /* IRQ12 mouse */
+ PIRQ_PENALTY_ISA_USED, /* IRQ13 fpe, sometimes */
+ PIRQ_PENALTY_ISA_USED, /* IRQ14 ide0 */
+ PIRQ_PENALTY_ISA_USED, /* IRQ15 ide1 */
+ /* >IRQ15 */
+};
+
+int __init acpi_irq_penalty_init(void)
+{
+ struct list_head *node = NULL;
+ struct acpi_pci_link *link = NULL;
+ int i = 0;
+
+
+ /*
+ * Update penalties to facilitate IRQ balancing.
+ */
+ list_for_each(node, &acpi_link.entries) {
+
+ link = list_entry(node, struct acpi_pci_link, node);
+ if (!link) {
+ printk(KERN_ERR PREFIX "Invalid link context\n");
+ continue;
+ }
+
+ /*
+ * reflect the possible and active irqs in the penalty table --
+ * useful for breaking ties.
+ */
+ if (link->irq.possible_count) {
+ int penalty =
+ PIRQ_PENALTY_PCI_POSSIBLE /
+ link->irq.possible_count;
+
+ for (i = 0; i < link->irq.possible_count; i++) {
+ if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
+ acpi_irq_penalty[link->irq.
+ possible[i]] +=
+ penalty;
+ }
+
+ } else if (link->irq.active) {
+ acpi_irq_penalty[link->irq.active] +=
+ PIRQ_PENALTY_PCI_POSSIBLE;
+ }
+ }
+ /* Add a penalty for the SCI */
+ acpi_irq_penalty[acpi_gbl_FADT.sci_interrupt] += PIRQ_PENALTY_PCI_USING;
+
+ return 0;
+}
+
+static int acpi_irq_balance = -1; /* 0: static, 1: balance */
+
+static int acpi_pci_link_allocate(struct acpi_pci_link *link)
+{
+ int irq;
+ int i;
+
+
+ if (link->irq.initialized) {
+ if (link->refcnt == 0)
+ /* This means the link is disabled but initialized */
+ acpi_pci_link_set(link, link->irq.active);
+ return 0;
+ }
+
+ /*
+ * search for active IRQ in list of possible IRQs.
+ */
+ for (i = 0; i < link->irq.possible_count; ++i) {
+ if (link->irq.active == link->irq.possible[i])
+ break;
+ }
+ /*
+ * forget active IRQ that is not in possible list
+ */
+ if (i == link->irq.possible_count) {
+ if (acpi_strict)
+ printk(KERN_WARNING PREFIX "_CRS %d not found"
+ " in _PRS\n", link->irq.active);
+ link->irq.active = 0;
+ }
+
+ /*
+ * if active found, use it; else pick entry from end of possible list.
+ */
+ if (link->irq.active) {
+ irq = link->irq.active;
+ } else {
+ irq = link->irq.possible[link->irq.possible_count - 1];
+ }
+
+ if (acpi_irq_balance || !link->irq.active) {
+ /*
+ * Select the best IRQ. This is done in reverse to promote
+ * the use of IRQs 9, 10, 11, and >15.
+ */
+ for (i = (link->irq.possible_count - 1); i >= 0; i--) {
+ if (acpi_irq_penalty[irq] >
+ acpi_irq_penalty[link->irq.possible[i]])
+ irq = link->irq.possible[i];
+ }
+ }
+
+ /* Attempt to enable the link device at this IRQ. */
+ if (acpi_pci_link_set(link, irq)) {
+ printk(KERN_ERR PREFIX "Unable to set IRQ for %s [%s]. "
+ "Try pci=noacpi or acpi=off\n",
+ acpi_device_name(link->device),
+ acpi_device_bid(link->device));
+ return -ENODEV;
+ } else {
+ acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
+ printk(PREFIX "%s [%s] enabled at IRQ %d\n",
+ acpi_device_name(link->device),
+ acpi_device_bid(link->device), link->irq.active);
+ }
+
+ link->irq.initialized = 1;
+
+ return 0;
+}
+
+/*
+ * acpi_pci_link_allocate_irq
+ * success: return IRQ >= 0
+ * failure: return -1
+ */
+
+int
+acpi_pci_link_allocate_irq(acpi_handle handle,
+ int index,
+ int *triggering, int *polarity, char **name)
+{
+ int result = 0;
+ struct acpi_device *device = NULL;
+ struct acpi_pci_link *link = NULL;
+
+
+ result = acpi_bus_get_device(handle, &device);
+ if (result) {
+ printk(KERN_ERR PREFIX "Invalid link device\n");
+ return -1;
+ }
+
+ link = acpi_driver_data(device);
+ if (!link) {
+ printk(KERN_ERR PREFIX "Invalid link context\n");
+ return -1;
+ }
+
+ /* TBD: Support multiple index (IRQ) entries per Link Device */
+ if (index) {
+ printk(KERN_ERR PREFIX "Invalid index %d\n", index);
+ return -1;
+ }
+
+ mutex_lock(&acpi_link_lock);
+ if (acpi_pci_link_allocate(link)) {
+ mutex_unlock(&acpi_link_lock);
+ return -1;
+ }
+
+ if (!link->irq.active) {
+ mutex_unlock(&acpi_link_lock);
+ printk(KERN_ERR PREFIX "Link active IRQ is 0!\n");
+ return -1;
+ }
+ link->refcnt++;
+ mutex_unlock(&acpi_link_lock);
+
+ if (triggering)
+ *triggering = link->irq.triggering;
+ if (polarity)
+ *polarity = link->irq.polarity;
+ if (name)
+ *name = acpi_device_bid(link->device);
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Link %s is referenced\n",
+ acpi_device_bid(link->device)));
+ return (link->irq.active);
+}
+
+/*
+ * We don't change link's irq information here. After it is reenabled, we
+ * continue use the info
+ */
+int acpi_pci_link_free_irq(acpi_handle handle)
+{
+ struct acpi_device *device = NULL;
+ struct acpi_pci_link *link = NULL;
+ acpi_status result;
+
+
+ result = acpi_bus_get_device(handle, &device);
+ if (result) {
+ printk(KERN_ERR PREFIX "Invalid link device\n");
+ return -1;
+ }
+
+ link = acpi_driver_data(device);
+ if (!link) {
+ printk(KERN_ERR PREFIX "Invalid link context\n");
+ return -1;
+ }
+
+ mutex_lock(&acpi_link_lock);
+ if (!link->irq.initialized) {
+ mutex_unlock(&acpi_link_lock);
+ printk(KERN_ERR PREFIX "Link isn't initialized\n");
+ return -1;
+ }
+#ifdef FUTURE_USE
+ /*
+ * The Link reference count allows us to _DISable an unused link
+ * and suspend time, and set it again on resume.
+ * However, 2.6.12 still has irq_router.resume
+ * which blindly restores the link state.
+ * So we disable the reference count method
+ * to prevent duplicate acpi_pci_link_set()
+ * which would harm some systems
+ */
+ link->refcnt--;
+#endif
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Link %s is dereferenced\n",
+ acpi_device_bid(link->device)));
+
+ if (link->refcnt == 0) {
+ acpi_evaluate_object(link->device->handle, "_DIS", NULL, NULL);
+ }
+ mutex_unlock(&acpi_link_lock);
+ return (link->irq.active);
+}
+
+/* --------------------------------------------------------------------------
+ Driver Interface
+ -------------------------------------------------------------------------- */
+
+static int acpi_pci_link_add(struct acpi_device *device)
+{
+ int result = 0;
+ struct acpi_pci_link *link = NULL;
+ int i = 0;
+ int found = 0;
+
+
+ if (!device)
+ return -EINVAL;
+
+ link = kzalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
+ if (!link)
+ return -ENOMEM;
+
+ link->device = device;
+ strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
+ strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
+ device->driver_data = link;
+
+ mutex_lock(&acpi_link_lock);
+ result = acpi_pci_link_get_possible(link);
+ if (result)
+ goto end;
+
+ /* query and set link->irq.active */
+ acpi_pci_link_get_current(link);
+
+ printk(KERN_INFO PREFIX "%s [%s] (IRQs", acpi_device_name(device),
+ acpi_device_bid(device));
+ for (i = 0; i < link->irq.possible_count; i++) {
+ if (link->irq.active == link->irq.possible[i]) {
+ printk(" *%d", link->irq.possible[i]);
+ found = 1;
+ } else
+ printk(" %d", link->irq.possible[i]);
+ }
+
+ printk(")");
+
+ if (!found)
+ printk(" *%d", link->irq.active);
+
+ if (!link->device->status.enabled)
+ printk(", disabled.");
+
+ printk("\n");
+
+ /* TBD: Acquire/release lock */
+ list_add_tail(&link->node, &acpi_link.entries);
+ acpi_link.count++;
+
+ end:
+ /* disable all links -- to be activated on use */
+ acpi_evaluate_object(device->handle, "_DIS", NULL, NULL);
+ mutex_unlock(&acpi_link_lock);
+
+ if (result)
+ kfree(link);
+
+ return result;
+}
+
+static int acpi_pci_link_resume(struct acpi_pci_link *link)
+{
+
+ if (link->refcnt && link->irq.active && link->irq.initialized)
+ return (acpi_pci_link_set(link, link->irq.active));
+ else
+ return 0;
+}
+
+static int irqrouter_resume(struct sys_device *dev)
+{
+ struct list_head *node = NULL;
+ struct acpi_pci_link *link = NULL;
+
+ list_for_each(node, &acpi_link.entries) {
+ link = list_entry(node, struct acpi_pci_link, node);
+ if (!link) {
+ printk(KERN_ERR PREFIX "Invalid link context\n");
+ continue;
+ }
+ acpi_pci_link_resume(link);
+ }
+ return 0;
+}
+
+static int acpi_pci_link_remove(struct acpi_device *device, int type)
+{
+ struct acpi_pci_link *link = NULL;
+
+
+ if (!device || !acpi_driver_data(device))
+ return -EINVAL;
+
+ link = acpi_driver_data(device);
+
+ mutex_lock(&acpi_link_lock);
+ list_del(&link->node);
+ mutex_unlock(&acpi_link_lock);
+
+ kfree(link);
+
+ return 0;
+}
+
+/*
+ * modify acpi_irq_penalty[] from cmdline
+ */
+static int __init acpi_irq_penalty_update(char *str, int used)
+{
+ int i;
+
+ for (i = 0; i < 16; i++) {
+ int retval;
+ int irq;
+
+ retval = get_option(&str, &irq);
+
+ if (!retval)
+ break; /* no number found */
+
+ if (irq < 0)
+ continue;
+
+ if (irq >= ARRAY_SIZE(acpi_irq_penalty))
+ continue;
+
+ if (used)
+ acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
+ else
+ acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
+
+ if (retval != 2) /* no next number */
+ break;
+ }
+ return 1;
+}
+
+/*
+ * We'd like PNP to call this routine for the
+ * single ISA_USED value for each legacy device.
+ * But instead it calls us with each POSSIBLE setting.
+ * There is no ISA_POSSIBLE weight, so we simply use
+ * the (small) PCI_USING penalty.
+ */
+void acpi_penalize_isa_irq(int irq, int active)
+{
+ if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
+ if (active)
+ acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
+ else
+ acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
+ }
+}
+
+/*
+ * Over-ride default table to reserve additional IRQs for use by ISA
+ * e.g. acpi_irq_isa=5
+ * Useful for telling ACPI how not to interfere with your ISA sound card.
+ */
+static int __init acpi_irq_isa(char *str)
+{
+ return acpi_irq_penalty_update(str, 1);
+}
+
+__setup("acpi_irq_isa=", acpi_irq_isa);
+
+/*
+ * Over-ride default table to free additional IRQs for use by PCI
+ * e.g. acpi_irq_pci=7,15
+ * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
+ */
+static int __init acpi_irq_pci(char *str)
+{
+ return acpi_irq_penalty_update(str, 0);
+}
+
+__setup("acpi_irq_pci=", acpi_irq_pci);
+
+static int __init acpi_irq_nobalance_set(char *str)
+{
+ acpi_irq_balance = 0;
+ return 1;
+}
+
+__setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
+
+int __init acpi_irq_balance_set(char *str)
+{
+ acpi_irq_balance = 1;
+ return 1;
+}
+
+__setup("acpi_irq_balance", acpi_irq_balance_set);
+
+/* FIXME: we will remove this interface after all drivers call pci_disable_device */
+static struct sysdev_class irqrouter_sysdev_class = {
+ .name = "irqrouter",
+ .resume = irqrouter_resume,
+};
+
+static struct sys_device device_irqrouter = {
+ .id = 0,
+ .cls = &irqrouter_sysdev_class,
+};
+
+static int __init irqrouter_init_sysfs(void)
+{
+ int error;
+
+
+ if (acpi_disabled || acpi_noirq)
+ return 0;
+
+ error = sysdev_class_register(&irqrouter_sysdev_class);
+ if (!error)
+ error = sysdev_register(&device_irqrouter);
+
+ return error;
+}
+
+device_initcall(irqrouter_init_sysfs);
+
+static int __init acpi_pci_link_init(void)
+{
+ if (acpi_noirq)
+ return 0;
+
+ if (acpi_irq_balance == -1) {
+ /* no command line switch: enable balancing in IOAPIC mode */
+ if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC)
+ acpi_irq_balance = 1;
+ else
+ acpi_irq_balance = 0;
+ }
+
+ acpi_link.count = 0;
+ INIT_LIST_HEAD(&acpi_link.entries);
+
+ if (acpi_bus_register_driver(&acpi_pci_link_driver) < 0)
+ return -ENODEV;
+
+ return 0;
+}
+
+subsys_initcall(acpi_pci_link_init);
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