linux-kernel - [PATCH 8/8] cpupower: Add cpuid cap flag for MSR_AMD

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Date:   Fri, 22 Jan 2021 11:39:29 -0600
From:   Nathan Fontenot <nathan.fontenot@....com>
To:     rrichter@....com, shuah@...nel.org, linux-kernel@...r.kernel.org,
        trenn@...e.com, linux-pm@...r.kernel.org
Subject: [PATCH 8/8] cpupower: Add cpuid cap flag for MSR_AMD_HWCR support

Remove the family check for accessing the MSR_AMD_HWCR MSR and replace
it with a cpupower cap flag.

This update also allows for the removal of the local cpupower_cpu_info
variable in cpufreq_has_boost_support() since we no longer need it to
check the family.

Signed-off-by: Nathan Fontenot <nathan.fontenot@....com>
---
 tools/power/cpupower/utils/helpers/cpuid.c   |    6 +++++-
 tools/power/cpupower/utils/helpers/helpers.h |    1 +
 tools/power/cpupower/utils/helpers/misc.c    |    7 +------
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/tools/power/cpupower/utils/helpers/cpuid.c b/tools/power/cpupower/utils/helpers/cpuid.c
index db2e88ceb67b..72eb43593180 100644
--- a/tools/power/cpupower/utils/helpers/cpuid.c
+++ b/tools/power/cpupower/utils/helpers/cpuid.c
@@ -129,9 +129,13 @@ int get_cpu_info(struct cpupower_cpu_info *cpu_info)
 	if (cpu_info->vendor == X86_VENDOR_AMD ||
 	    cpu_info->vendor == X86_VENDOR_HYGON) {
 		if (ext_cpuid_level >= 0x80000007) {
-			if (cpuid_edx(0x80000007) & (1 << 9))
+			if (cpuid_edx(0x80000007) & (1 << 9)) {
 				cpu_info->caps |= CPUPOWER_CAP_AMD_CPB;
 
+				if (cpu_info->family >= 0x17)
+					cpu_info->caps |= CPUPOWER_CAP_AMD_CPB_MSR;
+			}
+
 			if ((cpuid_edx(0x80000007) & (1 << 7)) &&
 			    cpu_info->family != 0x14) {
 				/* HW pstate was not implemented in family 0x14 */
diff --git a/tools/power/cpupower/utils/helpers/helpers.h b/tools/power/cpupower/utils/helpers/helpers.h
index 8a0c11c6ec63..33ffacee7fcb 100644
--- a/tools/power/cpupower/utils/helpers/helpers.h
+++ b/tools/power/cpupower/utils/helpers/helpers.h
@@ -72,6 +72,7 @@ enum cpupower_cpu_vendor {X86_VENDOR_UNKNOWN = 0, X86_VENDOR_INTEL,
 #define CPUPOWER_CAP_AMD_RDPRU		0x00000080
 #define CPUPOWER_CAP_AMD_HW_PSTATE	0x00000100
 #define CPUPOWER_CAP_AMD_PSTATEDEF	0x00000200
+#define CPUPOWER_CAP_AMD_CPB_MSR	0x00000400
 
 #define CPUPOWER_AMD_CPBDIS		0x02000000
 
diff --git a/tools/power/cpupower/utils/helpers/misc.c b/tools/power/cpupower/utils/helpers/misc.c
index f9bcce9c72d5..fc6e34511721 100644
--- a/tools/power/cpupower/utils/helpers/misc.c
+++ b/tools/power/cpupower/utils/helpers/misc.c
@@ -16,16 +16,11 @@
 int cpufreq_has_boost_support(unsigned int cpu, int *support, int *active,
 			int *states)
 {
-	struct cpupower_cpu_info cpu_info;
 	int ret;
 	unsigned long long val;
 
 	*support = *active = *states = 0;
 
-	ret = get_cpu_info(&cpu_info);
-	if (ret)
-		return ret;
-
 	if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_CPB) {
 		*support = 1;
 
@@ -34,7 +29,7 @@ int cpufreq_has_boost_support(unsigned int cpu, int *support, int *active,
 		 * has Hardware determined variable increments instead.
 		 */
 
-		if (cpu_info.family == 0x17 || cpu_info.family == 0x18) {
+		if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_CPB_MSR) {
 			if (!read_msr(cpu, MSR_AMD_HWCR, &val)) {
 				if (!(val & CPUPOWER_AMD_CPBDIS))
 					*active = 1;