[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: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

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,

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);
+	/*
+	 * 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(HWCR, value);
+		wrmsrl(MSR_K8_HWCR, value);
+	}
 #endif
 
 	/* Bit 31 in normal CPUID used for nonstandard 3DNow ID;

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