[PATCH v2 2/3] x86/topology: Name the AMD core-type values

Vishal Badole <[email protected]>
Newsgroups gmane.linux.acpi.devel,gmane.linux.kernel
Message-ID <[email protected]>
Replace the bare 0/1 in get_topology_cpu_type() with named constants
that mirror what the AMD APM publishes for CPUID Fn0x80000026
EBX[31:28] (Extended CPU Topology, Core Type):

  0 - Performance core
  1 - Efficient core
  2 - Low-power core (used by a follow-up)

No functional change.

Suggested-by: Borislav Petkov (AMD) <[email protected]>
Signed-off-by: Vishal Badole <[email protected]>
---
 arch/x86/include/asm/topology.h       | 6 ++++++
 arch/x86/kernel/cpu/topology_common.c | 4 ++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index ef76ba674f1b..1825691af941 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -114,6 +114,12 @@ enum x86_topology_domains {
 	TOPO_MAX_DOMAIN,
 };
 
+enum amd_cpu_type {
+	AMD_CPU_TYPE_PERFORMANCE	= 0,
+	AMD_CPU_TYPE_EFFICIENCY		= 1,
+	AMD_CPU_TYPE_LOW_POWER		= 2,
+};
+
 struct x86_topology_system {
 	unsigned int	dom_shifts[TOPO_MAX_DOMAIN];
 	unsigned int	dom_size[TOPO_MAX_DOMAIN];
diff --git a/arch/x86/kernel/cpu/topology_common.c b/arch/x86/kernel/cpu/topology_common.c
index b9d025f3373a..71b6c33afe0b 100644
--- a/arch/x86/kernel/cpu/topology_common.c
+++ b/arch/x86/kernel/cpu/topology_common.c
@@ -42,8 +42,8 @@ enum x86_topology_cpu_type get_topology_cpu_type(struct cpuinfo_x86 *c)
 	}
 	if (c->x86_vendor == X86_VENDOR_AMD) {
 		switch (c->topo.amd_type) {
-		case 0:	return TOPO_CPU_TYPE_PERFORMANCE;
-		case 1:	return TOPO_CPU_TYPE_EFFICIENCY;
+		case AMD_CPU_TYPE_PERFORMANCE:	return TOPO_CPU_TYPE_PERFORMANCE;
+		case AMD_CPU_TYPE_EFFICIENCY:	return TOPO_CPU_TYPE_EFFICIENCY;
 		}
 	}
 
-- 
2.34.1
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