3 files changed, 18 insertions, 13 deletions

diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
index 211ca3f7fd16..4ea15ca89b2b 100644
--- a/arch/x86/include/asm/acpi.h
+++ b/arch/x86/include/asm/acpi.h
@@ -88,6 +88,7 @@ extern int acpi_disabled;
 extern int acpi_pci_disabled;
 extern int acpi_skip_timer_override;
 extern int acpi_use_timer_override;
+extern int acpi_fix_pin2_polarity;
 
 extern u8 acpi_sci_flags;
 extern int acpi_sci_override_gsi;
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index b3a71137983a..3e6e2d68f761 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -72,6 +72,7 @@ u8 acpi_sci_flags __initdata;
 int acpi_sci_override_gsi __initdata;
 int acpi_skip_timer_override __initdata;
 int acpi_use_timer_override __initdata;
+int acpi_fix_pin2_polarity __initdata;
 
 #ifdef CONFIG_X86_LOCAL_APIC
 static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE;
@@ -415,10 +416,15 @@ acpi_parse_int_src_ovr(struct acpi_subtable_header * header,
                 return 0;
         }
 
-        if (acpi_skip_timer_override &&
-            intsrc->source_irq == 0 && intsrc->global_irq == 2) {
-                printk(PREFIX "BIOS IRQ0 pin2 override ignored.\n");
-                return 0;
+        if (intsrc->source_irq == 0 && intsrc->global_irq == 2) {
+                if (acpi_skip_timer_override) {
+                        printk(PREFIX "BIOS IRQ0 pin2 override ignored.\n");
+                        return 0;
+                }
+                if (acpi_fix_pin2_polarity && (intsrc->inti_flags & ACPI_MADT_POLARITY_MASK)) {
+                        intsrc->inti_flags &= ~ACPI_MADT_POLARITY_MASK;
+                        printk(PREFIX "BIOS IRQ0 pin2 override: forcing polarity to high active.\n");
+                }
         }
 
         mp_override_legacy_irq(intsrc->source_irq,
diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c
index 76b8cd953dee..9efbdcc56425 100644
--- a/arch/x86/kernel/early-quirks.c
+++ b/arch/x86/kernel/early-quirks.c
@@ -143,15 +143,10 @@ static void __init ati_bugs(int num, int slot, int func)
 
 static u32 __init ati_sbx00_rev(int num, int slot, int func)
 {
-        u32 old, d;
+        u32 d;
 
-        d = read_pci_config(num, slot, func, 0x70);
-        old = d;
-        d &= ~(1<<8);
-        write_pci_config(num, slot, func, 0x70, d);
         d = read_pci_config(num, slot, func, 0x8);
         d &= 0xff;
-        write_pci_config(num, slot, func, 0x70, old);
 
         return d;
 }
@@ -160,13 +155,16 @@ static void __init ati_bugs_contd(int num, int slot, int func)
 {
         u32 d, rev;
 
-        if (acpi_use_timer_override)
-                return;
-
         rev = ati_sbx00_rev(num, slot, func);
+        if (rev >= 0x40)
+                acpi_fix_pin2_polarity = 1;
+
         if (rev > 0x13)
                 return;
 
+        if (acpi_use_timer_override)
+                return;
+
         /* check for IRQ0 interrupt swap */
         d = read_pci_config(num, slot, func, 0x64);
         if (!(d & (1<<14)))