[PATCH] x86: fix the irqbalance quirk for E7320/E7520/E7525

Move the irqbalance quirks for E7320/E7520/E7525(Errata 23 in
http://download.intel.com/design/chipsets/specupdt/30304203.pdf) to early
quirks.

And add a PCI quirk for these platforms to check(which happens very late
during the boot) if the APIC routing is indeed set to default flat mode.

This fixes the breakage(in x86_64) of this quirk due to cpu hotplug which
selects physical mode instead of the logical flat(as needed for this errata
workaround).

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: "Li, Shaohua" <shaohua.li@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>

1 files changed, 21 insertions, 0 deletions

diff --git a/arch/i386/kernel/acpi/earlyquirk.c b/arch/i386/kernel/acpi/earlyquirk.c
index c9841692bb7c..4b60af7f91dd 100644
--- a/arch/i386/kernel/acpi/earlyquirk.c
+++ b/arch/i386/kernel/acpi/earlyquirk.c
@@ -10,6 +10,7 @@
 #include <asm/pci-direct.h>
 #include <asm/acpi.h>
 #include <asm/apic.h>
+#include <asm/irq.h>
 
 #ifdef CONFIG_ACPI
 
@@ -49,6 +50,24 @@ static int __init check_bridge(int vendor, int device)
         return 0;
 }
 
+static void check_intel(void)
+{
+        u16 vendor, device;
+
+        vendor = read_pci_config_16(0, 0, 0, PCI_VENDOR_ID);
+
+        if (vendor != PCI_VENDOR_ID_INTEL)
+                return;
+
+        device = read_pci_config_16(0, 0, 0, PCI_DEVICE_ID);
+#ifdef CONFIG_SMP
+        if (device == PCI_DEVICE_ID_INTEL_E7320_MCH ||
+            device == PCI_DEVICE_ID_INTEL_E7520_MCH ||
+            device == PCI_DEVICE_ID_INTEL_E7525_MCH)
+                quirk_intel_irqbalance();
+#endif
+}
+
 void __init check_acpi_pci(void)
 {
         int num, slot, func;
@@ -60,6 +79,8 @@ void __init check_acpi_pci(void)
         if (!early_pci_allowed())
                 return;
 
+        check_intel();
+
         /* Poor man's PCI discovery */
         for (num = 0; num < 32; num++) {
                 for (slot = 0; slot < 32; slot++) {