ACPI,PCI,IRQ: reduce resource requirements

Code has been redesigned to calculate penalty requirements on the fly. This
significantly simplifies the implementation and removes some of the init
calls from x86 architecture.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 68 insertions, 29 deletions

diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c
index ededa909df2f..cc0ba1651db1 100644
--- a/drivers/acpi/pci_link.c
+++ b/drivers/acpi/pci_link.c
@@ -36,6 +36,7 @@
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
+#include <linux/irq.h>
 
 #include "internal.h"
 
@@ -440,7 +441,6 @@ static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
 #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)
@@ -457,9 +457,9 @@ static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
         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 */
+        0,                              /* IRQ9  PCI, often acpi */
+        0,                              /* IRQ10 PCI */
+        0,                              /* IRQ11 PCI */
         PIRQ_PENALTY_ISA_USED,          /* IRQ12 mouse */
         PIRQ_PENALTY_ISA_USED,          /* IRQ13 fpe, sometimes */
         PIRQ_PENALTY_ISA_USED,          /* IRQ14 ide0 */
@@ -467,6 +467,60 @@ static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
         /* >IRQ15 */
 };
 
+static int acpi_irq_pci_sharing_penalty(int irq)
+{
+        struct acpi_pci_link *link;
+        int penalty = 0;
+
+        list_for_each_entry(link, &acpi_link_list, list) {
+                /*
+                 * If a link is active, penalize its IRQ heavily
+                 * so we try to choose a different IRQ.
+                 */
+                if (link->irq.active && link->irq.active == irq)
+                        penalty += PIRQ_PENALTY_PCI_USING;
+                else {
+                        int i;
+
+                        /*
+                         * If a link is inactive, penalize the IRQs it
+                         * might use, but not as severely.
+                         */
+                        for (i = 0; i < link->irq.possible_count; i++)
+                                if (link->irq.possible[i] == irq)
+                                        penalty += PIRQ_PENALTY_PCI_POSSIBLE /
+                                                link->irq.possible_count;
+                }
+        }
+
+        return penalty;
+}
+
+static int acpi_irq_get_penalty(int irq)
+{
+        int penalty = 0;
+
+        if (irq < ACPI_MAX_ISA_IRQ)
+                penalty += acpi_irq_penalty[irq];
+
+        /*
+        * Penalize IRQ used by ACPI SCI. If ACPI SCI pin attributes conflict
+        * with PCI IRQ attributes, mark ACPI SCI as ISA_ALWAYS so it won't be
+        * use for PCI IRQs.
+        */
+        if (irq == acpi_gbl_FADT.sci_interrupt) {
+                u32 type = irq_get_trigger_type(irq) & IRQ_TYPE_SENSE_MASK;
+
+                if (type != IRQ_TYPE_LEVEL_LOW)
+                        penalty += PIRQ_PENALTY_ISA_ALWAYS;
+                else
+                        penalty += PIRQ_PENALTY_PCI_USING;
+        }
+
+        penalty += acpi_irq_pci_sharing_penalty(irq);
+        return penalty;
+}
+
 int __init acpi_irq_penalty_init(void)
 {
         struct acpi_pci_link *link;
@@ -547,12 +601,12 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link)
                  * 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]])
+                        if (acpi_irq_get_penalty(irq) >
+                            acpi_irq_get_penalty(link->irq.possible[i]))
                                 irq = link->irq.possible[i];
                 }
         }
-        if (acpi_irq_penalty[irq] >= PIRQ_PENALTY_ISA_ALWAYS) {
+        if (acpi_irq_get_penalty(irq) >= PIRQ_PENALTY_ISA_ALWAYS) {
                 printk(KERN_ERR PREFIX "No IRQ available for %s [%s]. "
                             "Try pci=noacpi or acpi=off\n",
                             acpi_device_name(link->device),
@@ -568,7 +622,6 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link)
                             acpi_device_bid(link->device));
                 return -ENODEV;
         } else {
-                acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
                 printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n",
                        acpi_device_name(link->device),
                        acpi_device_bid(link->device), link->irq.active);
@@ -800,9 +853,10 @@ static int __init acpi_irq_penalty_update(char *str, int used)
                         continue;
 
                 if (used)
-                        acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
+                        acpi_irq_penalty[irq] = acpi_irq_get_penalty(irq) +
+                                PIRQ_PENALTY_ISA_USED;
                 else
-                        acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
+                        acpi_irq_penalty[irq] = 0;
 
                 if (retval != 2)        /* no next number */
                         break;
@@ -819,34 +873,19 @@ static int __init acpi_irq_penalty_update(char *str, int used)
  */
 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;
-        }
+        if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty))
+                acpi_irq_penalty[irq] = acpi_irq_get_penalty(irq) +
+                        active ? PIRQ_PENALTY_ISA_USED : PIRQ_PENALTY_PCI_USING;
 }
 
 bool acpi_isa_irq_available(int irq)
 {
         return irq >= 0 && (irq >= ARRAY_SIZE(acpi_irq_penalty) ||
-                            acpi_irq_penalty[irq] < PIRQ_PENALTY_ISA_ALWAYS);
+                    acpi_irq_get_penalty(irq) < PIRQ_PENALTY_ISA_ALWAYS);
 }
 
-/*
- * Penalize IRQ used by ACPI SCI. If ACPI SCI pin attributes conflict with
- * PCI IRQ attributes, mark ACPI SCI as ISA_ALWAYS so it won't be use for
- * PCI IRQs.
- */
 void acpi_penalize_sci_irq(int irq, int trigger, int polarity)
 {
-        if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
-                if (trigger != ACPI_MADT_TRIGGER_LEVEL ||
-                    polarity != ACPI_MADT_POLARITY_ACTIVE_LOW)
-                        acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_ALWAYS;
-                else
-                        acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
-        }
 }
 
 /*