[ACPI] automatic workaround for NFORCE timer-override BIOS bug

http://bugzilla.kernel.org/show_bug.cgi?id=3551Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

arch/i386/kernel/acpi/Makefile

-obj-$(CONFIG_ACPI_BOOT)		:= boot.o
+obj-$(CONFIG_ACPI_BOOT)		:= boot.o earlyquirk.o
 obj-$(CONFIG_ACPI_SLEEP)	+= sleep.o wakeup.o
 

arch/i386/kernel/acpi/boot.c

@@ -817,6 +817,10 @@ acpi_boot_init (void)
 		return error;
 	}
 
+#ifdef __i386__
+	check_acpi_pci();
+#endif
+
 	acpi_table_parse(ACPI_BOOT, acpi_parse_sbf);
 
 	/*

arch/i386/kernel/acpi/earlyquirk.c

+/* 
+ * Do early PCI probing for bug detection when the main PCI subsystem is 
+ * not up yet.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <asm/pci-direct.h>
+#include <asm/acpi.h>
+
+static int __init check_bridge(int vendor, int device) 
+{
+	/* According to Nvidia all timer overrides are bogus. Just ignore
+	   them all. */
+	if (vendor == PCI_VENDOR_ID_NVIDIA) { 
+		acpi_skip_timer_override = 1; 		
+	}
+	return 0;
+}
+   
+void __init check_acpi_pci(void) 
+{ 
+	int num,slot,func; 
+
+	/* Assume the machine supports type 1. If not it will 
+	   always read ffffffff and should not have any side effect. */
+
+	/* Poor man's PCI discovery */
+	for (num = 0; num < 32; num++) { 
+		for (slot = 0; slot < 32; slot++) { 
+			for (func = 0; func < 8; func++) { 
+				u32 class;
+				u32 vendor;
+				class = read_pci_config(num,slot,func,
+							PCI_CLASS_REVISION);
+				if (class == 0xffffffff)
+					break; 
+
+				if ((class >> 16) != PCI_CLASS_BRIDGE_PCI)
+					continue; 
+				
+				vendor = read_pci_config(num, slot, func, 
+							 PCI_VENDOR_ID);
+				
+				if (check_bridge(vendor&0xffff, vendor >> 16))
+					return; 
+			} 
+			
+		}
+	}
+}

include/asm-i386/acpi.h

@@ -138,6 +138,8 @@ extern int acpi_gsi_to_irq(u32 gsi, unsigned int *irq);
 extern int skip_ioapic_setup;
 extern int acpi_skip_timer_override;
 
+extern void check_acpi_pci(void);
+
 static inline void disable_ioapic_setup(void)
 {
 	skip_ioapic_setup = 1;

include/asm-i386/pci-direct.h

+#include "asm-x86_64/pci-direct.h"