[PATCH] Fix up TLB flush filter disabling

I checked with AMD and they requested to only disable it for family 15.
Also disable it for i386 too. And some style fixes.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 29 insertions, 10 deletions

diff --git a/arch/i386/kernel/cpu/amd.c b/arch/i386/kernel/cpu/amd.c
index 73aeaf5a9d4e..4c1ddf2b57cc 100644
--- a/arch/i386/kernel/cpu/amd.c
+++ b/arch/i386/kernel/cpu/amd.c
@@ -28,6 +28,22 @@ static void __init init_amd(struct cpuinfo_x86 *c)
         int mbytes = num_physpages >> (20-PAGE_SHIFT);
         int r;
 
+#ifdef CONFIG_SMP
+        unsigned long value;
+
+        /* Disable TLB flush filter by setting HWCR.FFDIS on K8
+         * bit 6 of msr C001_0015
+         *
+         * Errata 63 for SH-B3 steppings
+         * Errata 122 for all steppings (F+ have it disabled by default)
+         */
+        if (c->x86 == 15) {
+                rdmsrl(MSR_K7_HWCR, value);
+                value |= 1 << 6;
+                wrmsrl(MSR_K7_HWCR, value);
+        }
+#endif
+
         /*
          *      FIXME: We should handle the K5 here. Set up the write
          *      range and also turn on MSR 83 bits 4 and 31 (write alloc,
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index 238f73e1a834..257f5ba17902 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -831,8 +831,6 @@ static void __init amd_detect_cmp(struct cpuinfo_x86 *c)
 #endif
 }
 
-#define HWCR 0xc0010015
-
 static int __init init_amd(struct cpuinfo_x86 *c)
 {
         int r;
@@ -841,14 +839,18 @@ static int __init init_amd(struct cpuinfo_x86 *c)
 #ifdef CONFIG_SMP
         unsigned long value;
 
-        // Disable TLB flush filter by setting HWCR.FFDIS:
-        // bit 6 of msr C001_0015
-        //
-        // Errata 63 for SH-B3 steppings
-        // Errata 122 for all(?) steppings
-        rdmsrl(HWCR, value);
-        value |= 1 << 6;
-        wrmsrl(HWCR, value);
+        /*
+         * Disable TLB flush filter by setting HWCR.FFDIS on K8
+         * bit 6 of msr C001_0015
+         *
+         * Errata 63 for SH-B3 steppings
+         * Errata 122 for all steppings (F+ have it disabled by default)
+         */
+        if (c->x86 == 15) {
+                rdmsrl(MSR_K8_HWCR, value);
+                value |= 1 << 6;
+                wrmsrl(MSR_K8_HWCR, value);
+        }
 #endif
 
         /* Bit 31 in normal CPUID used for nonstandard 3DNow ID;
diff --git a/include/asm-x86_64/msr.h b/include/asm-x86_64/msr.h
index 4d727f3f5550..5a7fe3c6c3d8 100644
--- a/include/asm-x86_64/msr.h
+++ b/include/asm-x86_64/msr.h
@@ -234,6 +234,7 @@ static inline unsigned int cpuid_edx(unsigned int op)
 #define MSR_K8_TOP_MEM1            0xC001001A
 #define MSR_K8_TOP_MEM2            0xC001001D
 #define MSR_K8_SYSCFG              0xC0010010
+#define MSR_K8_HWCR                0xC0010015
 
 /* K6 MSRs */
 #define MSR_K6_EFER                     0xC0000080