x86, ioapic: Optimize pin_2_irq

[safe/jmp/linux-2.6] / arch / x86 / kernel / apic / io_apic.c

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 463de9a..0d35f46 100644 (file)
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -36,6 +36,7 @@
 #include <linux/freezer.h>
 #include <linux/kthread.h>
 #include <linux/jiffies.h>     /* time_after() */
+#include <linux/slab.h>
 #ifdef CONFIG_ACPI
 #include <acpi/acpi_bus.h>
 #endif
@@ -88,6 +89,9 @@ int nr_ioapics;
 /* IO APIC gsi routing info */
 struct mp_ioapic_gsi  mp_gsi_routing[MAX_IO_APICS];
 
+/* The last gsi number used */
+u32 gsi_end;
+
 /* MP IRQ source entries */
 struct mpc_intsrc mp_irqs[MAX_IRQ_SOURCES];
 
@@ -1015,7 +1019,7 @@ static inline int irq_trigger(int idx)
 int (*ioapic_renumber_irq)(int ioapic, int irq);
 static int pin_2_irq(int idx, int apic, int pin)
 {
-       int irq, i;
+       int irq;
        int bus = mp_irqs[idx].srcbus;
 
        /*
@@ -1027,18 +1031,13 @@ static int pin_2_irq(int idx, int apic, int pin)
        if (test_bit(bus, mp_bus_not_pci)) {
                irq = mp_irqs[idx].srcbusirq;
        } else {
-               /*
-                * PCI IRQs are mapped in order
-                */
-               i = irq = 0;
-               while (i < apic)
-                       irq += nr_ioapic_registers[i++];
-               irq += pin;
+               u32 gsi = mp_gsi_routing[apic].gsi_base + pin;
                /*
                  * For MPS mode, so far only needed by ES7000 platform
                  */
                if (ioapic_renumber_irq)
-                       irq = ioapic_renumber_irq(apic, irq);
+                       gsi = ioapic_renumber_irq(apic, gsi);
+               irq = gsi;
        }
 
 #ifdef CONFIG_X86_32
@@ -1949,20 +1948,8 @@ static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
 
 void __init enable_IO_APIC(void)
 {
-       union IO_APIC_reg_01 reg_01;
        int i8259_apic, i8259_pin;
        int apic;
-       unsigned long flags;
-
-       /*
-        * The number of IO-APIC IRQ registers (== #pins):
-        */
-       for (apic = 0; apic < nr_ioapics; apic++) {
-               raw_spin_lock_irqsave(&ioapic_lock, flags);
-               reg_01.raw = io_apic_read(apic, 1);
-               raw_spin_unlock_irqrestore(&ioapic_lock, flags);
-               nr_ioapic_registers[apic] = reg_01.bits.entries+1;
-       }
 
        if (!legacy_pic->nr_legacy_irqs)
                return;
@@ -3854,7 +3841,11 @@ int __init io_apic_get_redir_entries (int ioapic)
        reg_01.raw = io_apic_read(ioapic, 1);
        raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 
-       return reg_01.bits.entries;
+       /* The register returns the maximum index redir index
+        * supported, which is one less than the total number of redir
+        * entries.
+        */
+       return reg_01.bits.entries + 1;
 }
 
 void __init probe_nr_irqs_gsi(void)
@@ -3870,7 +3861,7 @@ void __init probe_nr_irqs_gsi(void)
 
                nr = 0;
                for (idx = 0; idx < nr_ioapics; idx++)
-                       nr += io_apic_get_redir_entries(idx) + 1;
+                       nr += io_apic_get_redir_entries(idx);
 
                if (nr > nr_irqs_gsi)
                        nr_irqs_gsi = nr;
@@ -4081,22 +4072,27 @@ int __init io_apic_get_version(int ioapic)
        return reg_01.bits.version;
 }
 
-int acpi_get_override_irq(int bus_irq, int *trigger, int *polarity)
+int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity)
 {
-       int i;
+       int ioapic, pin, idx;
 
        if (skip_ioapic_setup)
                return -1;
 
-       for (i = 0; i < mp_irq_entries; i++)
-               if (mp_irqs[i].irqtype == mp_INT &&
-                   mp_irqs[i].srcbusirq == bus_irq)
-                       break;
-       if (i >= mp_irq_entries)
+       ioapic = mp_find_ioapic(gsi);
+       if (ioapic < 0)
                return -1;
 
-       *trigger = irq_trigger(i);
-       *polarity = irq_polarity(i);
+       pin = mp_find_ioapic_pin(ioapic, gsi);
+       if (pin < 0)
+               return -1;
+
+       idx = find_irq_entry(ioapic, pin, mp_INT);
+       if (idx < 0)
+               return -1;
+
+       *trigger = irq_trigger(idx);
+       *polarity = irq_polarity(idx);
        return 0;
 }
 
@@ -4237,7 +4233,7 @@ void __init ioapic_insert_resources(void)
        }
 }
 
-int mp_find_ioapic(int gsi)
+int mp_find_ioapic(u32 gsi)
 {
        int i = 0;
 
@@ -4252,7 +4248,7 @@ int mp_find_ioapic(int gsi)
        return -1;
 }
 
-int mp_find_ioapic_pin(int ioapic, int gsi)
+int mp_find_ioapic_pin(int ioapic, u32 gsi)
 {
        if (WARN_ON(ioapic == -1))
                return -1;
@@ -4280,6 +4276,7 @@ static int bad_ioapic(unsigned long address)
 void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
 {
        int idx = 0;
+       int entries;
 
        if (bad_ioapic(address))
                return;
@@ -4298,9 +4295,17 @@ void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
         * Build basic GSI lookup table to facilitate gsi->io_apic lookups
         * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
         */
+       entries = io_apic_get_redir_entries(idx);
        mp_gsi_routing[idx].gsi_base = gsi_base;
-       mp_gsi_routing[idx].gsi_end = gsi_base +
-           io_apic_get_redir_entries(idx);
+       mp_gsi_routing[idx].gsi_end = gsi_base + entries - 1;
+
+       /*
+        * The number of IO-APIC IRQ registers (== #pins):
+        */
+       nr_ioapic_registers[idx] = entries;
+
+       if (mp_gsi_routing[idx].gsi_end > gsi_end)
+               gsi_end = mp_gsi_routing[idx].gsi_end;
 
        printk(KERN_INFO "IOAPIC[%d]: apic_id %d, version %d, address 0x%x, "
               "GSI %d-%d\n", idx, mp_ioapics[idx].apicid,