[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, 35 insertions, 11 deletions

diff --git a/arch/i386/kernel/quirks.c b/arch/i386/kernel/quirks.c
index 9f6ab1789bb0..a01320a7b636 100644
--- a/arch/i386/kernel/quirks.c
+++ b/arch/i386/kernel/quirks.c
@@ -3,10 +3,23 @@
  */
 #include <linux/pci.h>
 #include <linux/irq.h>
+#include <asm/pci-direct.h>
+#include <asm/genapic.h>
+#include <asm/cpu.h>
 
 #if defined(CONFIG_X86_IO_APIC) && defined(CONFIG_SMP) && defined(CONFIG_PCI)
+static void __devinit verify_quirk_intel_irqbalance(struct pci_dev *dev)
+{
+#ifdef CONFIG_X86_64
+        if (genapic !=  &apic_flat)
+                panic("APIC mode must be flat on this system\n");
+#elif defined(CONFIG_X86_GENERICARCH)
+        if (genapic != &apic_default)
+                panic("APIC mode must be default(flat) on this system. Use apic=default\n");
+#endif
+}
 
-static void __devinit quirk_intel_irqbalance(struct pci_dev *dev)
+void __init quirk_intel_irqbalance(void)
 {
         u8 config, rev;
         u32 word;
@@ -16,18 +29,18 @@ static void __devinit quirk_intel_irqbalance(struct pci_dev *dev)
          * based platforms.
          * Disable SW irqbalance/affinity on those platforms.
          */
-        pci_read_config_byte(dev, PCI_CLASS_REVISION, &rev);
+        rev = read_pci_config_byte(0, 0, 0, PCI_CLASS_REVISION);
         if (rev > 0x9)
                 return;
 
         printk(KERN_INFO "Intel E7520/7320/7525 detected.");
 
-        /* enable access to config space*/
-        pci_read_config_byte(dev, 0xf4, &config);
-        pci_write_config_byte(dev, 0xf4, config|0x2);
+        /* enable access to config space */
+        config = read_pci_config_byte(0, 0, 0, 0xf4);
+        write_pci_config_byte(0, 0, 0, 0xf4, config|0x2);
 
         /* read xTPR register */
-        raw_pci_ops->read(0, 0, 0x40, 0x4c, 2, &word);
+        word = read_pci_config_16(0, 0, 0x40, 0x4c);
 
         if (!(word & (1 << 13))) {
                 printk(KERN_INFO "Disabling irq balancing and affinity\n");
@@ -38,13 +51,24 @@ static void __devinit quirk_intel_irqbalance(struct pci_dev *dev)
 #ifdef CONFIG_PROC_FS
                 no_irq_affinity = 1;
 #endif
+#ifdef CONFIG_HOTPLUG_CPU
+                printk(KERN_INFO "Disabling cpu hotplug control\n");
+                enable_cpu_hotplug = 0;
+#endif
+#ifdef CONFIG_X86_64
+                /* force the genapic selection to flat mode so that
+                 * interrupts can be redirected to more than one CPU.
+                 */
+                genapic_force = &apic_flat;
+#endif
         }
 
-        /* put back the original value for config space*/
+        /* put back the original value for config space */
         if (!(config & 0x2))
-                pci_write_config_byte(dev, 0xf4, config);
+                write_pci_config_byte(0, 0, 0, 0xf4, config);
 }
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_E7320_MCH,  quirk_intel_irqbalance);
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_E7525_MCH,  quirk_intel_irqbalance);
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_E7520_MCH,  quirk_intel_irqbalance);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_E7320_MCH,  verify_quirk_intel_irqbalance);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_E7525_MCH,  verify_quirk_intel_irqbalance);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL,   PCI_DEVICE_ID_INTEL_E7520_MCH,  verify_quirk_intel_irqbalance);
+
 #endif