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authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-06 12:19:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-06 12:19:38 -0700
commit18b15fcde715a5512671af9d72a76e7f6d7cb6f0 (patch)
tree073ca0c45f48abae1809e86efc06e22e7528f0e7 /arch/x86/kernel/cpu/amd.c
parent271fd5d7286eb931142402c170943d14640bb922 (diff)
parentab27a20e6212cd1d96d813352b47e1fc1cfd01db (diff)
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes form Peter Anvin * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: intel_mid_powerbtn: mark irq as IRQF_NO_SUSPEND arch/x86/platform/geode/net5501.c: change active_low to 0 for LED driver x86, relocs: Remove an unused variable asm-generic: Use __BITS_PER_LONG in statfs.h x86/amd: Re-enable CPU topology extensions in case BIOS has disabled it
Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
-rw-r--r--arch/x86/kernel/cpu/amd.c18
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 1c67ca100e4..146bb6218ee 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -580,6 +580,24 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
}
}
+ /* re-enable TopologyExtensions if switched off by BIOS */
+ if ((c->x86 == 0x15) &&
+ (c->x86_model >= 0x10) && (c->x86_model <= 0x1f) &&
+ !cpu_has(c, X86_FEATURE_TOPOEXT)) {
+ u64 val;
+
+ if (!rdmsrl_amd_safe(0xc0011005, &val)) {
+ val |= 1ULL << 54;
+ wrmsrl_amd_safe(0xc0011005, val);
+ rdmsrl(0xc0011005, val);
+ if (val & (1ULL << 54)) {
+ set_cpu_cap(c, X86_FEATURE_TOPOEXT);
+ printk(KERN_INFO FW_INFO "CPU: Re-enabling "
+ "disabled Topology Extensions Support\n");
+ }
+ }
+ }
+
cpu_detect_cache_sizes(c);
/* Multi core CPU? */