linux-kernel - [PATCH 3/3] cpufreq/amd-pstate: Remove warning for X86_FEATURE

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Message-ID: <20240813095459.2122-1-gautham.shenoy@amd.com>
Date: Tue, 13 Aug 2024 15:24:59 +0530
From: "Gautham R. Shenoy" <gautham.shenoy@....com>
To: "Rafael J . Wysocki" <rafael@...nel.org>, Viresh Kumar
	<viresh.kumar@...aro.org>
CC: <linux-pm@...r.kernel.org>, <linux-kernel@...r.kernel.org>, "Mario
 Limonciello" <mario.limonciello@....com>, Huang Rui <ray.huang@....com>,
	"Perry Yuan" <perry.yuan@....com>, Dan Carpenter <dan.carpenter@...aro.org>,
	Dhananjay Ugwekar <Dhananjay.Ugwekar@....com>, David Wang <00107082@....com>,
	"Gautham R . Shenoy" <gautham.shenoy@....com>
Subject: [PATCH 3/3] cpufreq/amd-pstate: Remove warning for X86_FEATURE_CPPC on Zen1 and Zen2

commit bff7d13c190a ("cpufreq: amd-pstate: add debug message while
CPPC is supported and disabled by SBIOS") issues a warning on plaforms
where the X86_FEATURE_CPPC is expected to be enabled, but is not due
to it being disabled in the BIOS.

This feature bit corresponds to CPUID 0x80000008.ebx[27] which is a
reserved bit on the Zen1 and Zen2 platforms, and is expected to be
cleared on these platforms. Thus printing the warning message for Zen1
and Zen2 models when X86_FEATURE_CPPC is incorrect. Fix this.

Fixes: bff7d13c190a ("cpufreq: amd-pstate: add debug message while CPPC is supported and disabled by SBIOS")
Reported-by: David Wang <00107082@....com>
Closes: https://lore.kernel.org/lkml/20240730140111.4491-1-00107082@163.com/
Signed-off-by: Gautham R. Shenoy <gautham.shenoy@....com>
---
 drivers/cpufreq/amd-pstate.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 89bda7a2bb8d..66002718397c 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -1841,10 +1841,8 @@ static bool amd_cppc_supported(void)
 	 * the code is added for debugging purposes.
 	 */
 	if (!cpu_feature_enabled(X86_FEATURE_CPPC)) {
-		if (cpu_feature_enabled(X86_FEATURE_ZEN1) || cpu_feature_enabled(X86_FEATURE_ZEN2)) {
-			if (c->x86_model > 0x60 && c->x86_model < 0xaf)
-				warn = true;
-		} else if (cpu_feature_enabled(X86_FEATURE_ZEN3) || cpu_feature_enabled(X86_FEATURE_ZEN4)) {
+		if (cpu_feature_enabled(X86_FEATURE_ZEN3) ||
+		    cpu_feature_enabled(X86_FEATURE_ZEN4)) {
 			if ((c->x86_model > 0x10 && c->x86_model < 0x1F) ||
 					(c->x86_model > 0x40 && c->x86_model < 0xaf))
 				warn = true;
-- 
2.34.1