Explicitly define the AMD64_CPUID_FN_EXT MSR used to toggle the extended
features. Also define and use the bits necessary an old TOPOEXT fixup on
AMD Family 0x15 processors.
No functional changes intended.
Signed-off-by: K Prateek Nayak <kprateek.nayak@xxxxxxx>
---
Changelog v2..v3:
o New patch.
Note: The definition of MSR_AMD64_CPUID_FN_EXT_TOPOEXT_ENABLED crosses
the 100 column limit and results in a checkpatch warning.
msr-index.h contains a couple more examples where the definitions with
very explicit naming crosses 100 columns and I've decided to retain the
same despite the warning.
If this needs to be changed, please let me know and I'll address it in
the next version.
---
arch/x86/include/asm/msr-index.h | 5 +++++
arch/x86/kernel/cpu/topology_amd.c | 7 ++++---
2 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 2d5595bdfa27..7931f9b3250b 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -630,6 +630,11 @@
#define MSR_AMD_PPIN 0xc00102f1
#define MSR_AMD64_CPUID_FN_7 0xc0011002
#define MSR_AMD64_CPUID_FN_1 0xc0011004
+
+#define MSR_AMD64_CPUID_FN_EXT 0xc0011005
+#define MSR_AMD64_CPUID_FN_EXT_TOPOEXT_ENABLED_BIT 54
+#define MSR_AMD64_CPUID_FN_EXT_TOPOEXT_ENABLED BIT_ULL(MSR_AMD64_CPUID_FN_EXT_TOPOEXT_ENABLED_BIT)
+
#define MSR_AMD64_LS_CFG 0xc0011020
#define MSR_AMD64_DC_CFG 0xc0011022
#define MSR_AMD64_TW_CFG 0xc0011023
diff --git a/arch/x86/kernel/cpu/topology_amd.c b/arch/x86/kernel/cpu/topology_amd.c
index 843b1655ab45..bb00dc6433eb 100644
--- a/arch/x86/kernel/cpu/topology_amd.c
+++ b/arch/x86/kernel/cpu/topology_amd.c
@@ -158,11 +158,12 @@ static void topoext_fixup(struct topo_scan *tscan)
c->x86 != 0x15 || c->x86_model < 0x10 || c->x86_model > 0x6f)
return;
- if (msr_set_bit(0xc0011005, 54) <= 0)
+ if (msr_set_bit(MSR_AMD64_CPUID_FN_EXT,
+ MSR_AMD64_CPUID_FN_EXT_TOPOEXT_ENABLED_BIT) <= 0)
return;
- rdmsrq(0xc0011005, msrval);
- if (msrval & BIT_64(54)) {
+ rdmsrq(MSR_AMD64_CPUID_FN_EXT, msrval);
+ if (msrval & MSR_AMD64_CPUID_FN_EXT_TOPOEXT_ENABLED) {
set_cpu_cap(c, X86_FEATURE_TOPOEXT);
pr_info_once(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
}
--
2.34.1
