linux-kernel - [PATCH 2/2] cpufreq: amd-pstate: Use amd_get_highest

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Tue, 25 Jun 2024 23:20:43 -0500
From: Mario Limonciello <mario.limonciello@....com>
To: Borislav Petkov <bp@...en8.de>, "Gautham R . Shenoy"
	<gautham.shenoy@....com>, Perry Yuan <perry.yuan@....com>
CC: Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>,
	"Dave Hansen" <dave.hansen@...ux.intel.com>, "maintainer:X86 ARCHITECTURE
 (32-BIT AND 64-BIT)" <x86@...nel.org>, "H . Peter Anvin" <hpa@...or.com>,
	Huang Rui <ray.huang@....com>, Mario Limonciello <mario.limonciello@....com>,
	"Rafael J . Wysocki" <rafael@...nel.org>, Viresh Kumar
	<viresh.kumar@...aro.org>, Nikolay Borisov <nik.borisov@...e.com>, Peter
 Zijlstra <peterz@...radead.org>, "open list:X86 ARCHITECTURE (32-BIT AND
 64-BIT)" <linux-kernel@...r.kernel.org>, "open list:AMD PSTATE DRIVER"
	<linux-pm@...r.kernel.org>
Subject: [PATCH 2/2] cpufreq: amd-pstate: Use amd_get_highest_perf() to lookup perf values

To keep consistency with amd-pstate and acpi-cpufreq behavior, use
amd_get_highest_perf() to find the highest perf value for a given
platform.

This fixes the exact same problem as commit bf202e654bfa ("cpufreq:
amd-pstate: fix the highest frequency issue which limits performance")
from happening on acpi-cpufreq too.

Signed-off-by: Mario Limonciello <mario.limonciello@....com>
---
 arch/x86/kernel/cpu/amd.c    | 16 +++++++++++++++-
 drivers/cpufreq/amd-pstate.c | 21 ++-------------------
 2 files changed, 17 insertions(+), 20 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 8b730193d79e..e69f640cc248 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -1218,7 +1218,21 @@ u32 amd_get_highest_perf(void)
 		}
 	}
 
-	return CPPC_HIGHEST_PERF_MAX;
+	/*
+	 * For AMD CPUs with Family ID 19H and Model ID range 0x70 to 0x7f,
+	 * the highest performance level is set to 196.
+	 * https://bugzilla.kernel.org/show_bug.cgi?id=218759
+	 */
+	if (cpu_feature_enabled(X86_FEATURE_ZEN4)) {
+		switch (c->x86_model) {
+		case 0x70 ... 0x7f:
+			return CPPC_HIGHEST_PERF_PERFORMANCE;
+		default:
+			return CPPC_HIGHEST_PERF_DEFAULT;
+		}
+	}
+
+	return CPPC_HIGHEST_PERF_DEFAULT;
 }
 EXPORT_SYMBOL_GPL(amd_get_highest_perf);
 
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 80eaa58f1405..f468d8562e17 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -52,8 +52,6 @@
 #define AMD_PSTATE_TRANSITION_LATENCY	20000
 #define AMD_PSTATE_TRANSITION_DELAY	1000
 #define AMD_PSTATE_FAST_CPPC_TRANSITION_DELAY 600
-#define CPPC_HIGHEST_PERF_PERFORMANCE	196
-#define CPPC_HIGHEST_PERF_DEFAULT	166
 
 #define AMD_CPPC_EPP_PERFORMANCE		0x00
 #define AMD_CPPC_EPP_BALANCE_PERFORMANCE	0x80
@@ -349,21 +347,6 @@ static inline int amd_pstate_enable(bool enable)
 	return static_call(amd_pstate_enable)(enable);
 }
 
-static u32 amd_pstate_highest_perf_set(struct amd_cpudata *cpudata)
-{
-	struct cpuinfo_x86 *c = &cpu_data(0);
-
-	/*
-	 * For AMD CPUs with Family ID 19H and Model ID range 0x70 to 0x7f,
-	 * the highest performance level is set to 196.
-	 * https://bugzilla.kernel.org/show_bug.cgi?id=218759
-	 */
-	if (c->x86 == 0x19 && (c->x86_model >= 0x70 && c->x86_model <= 0x7f))
-		return CPPC_HIGHEST_PERF_PERFORMANCE;
-
-	return CPPC_HIGHEST_PERF_DEFAULT;
-}
-
 static int pstate_init_perf(struct amd_cpudata *cpudata)
 {
 	u64 cap1;
@@ -380,7 +363,7 @@ static int pstate_init_perf(struct amd_cpudata *cpudata)
 	 * the default max perf.
 	 */
 	if (cpudata->hw_prefcore)
-		highest_perf = amd_pstate_highest_perf_set(cpudata);
+		highest_perf = amd_get_highest_perf();
 	else
 		highest_perf = AMD_CPPC_HIGHEST_PERF(cap1);
 
@@ -404,7 +387,7 @@ static int cppc_init_perf(struct amd_cpudata *cpudata)
 		return ret;
 
 	if (cpudata->hw_prefcore)
-		highest_perf = amd_pstate_highest_perf_set(cpudata);
+		highest_perf = amd_get_highest_perf();
 	else
 		highest_perf = cppc_perf.highest_perf;
 
-- 
2.43.0