linux-kernel - [PATCH v5 4/8] cpufreq: amd-pstate: fix max_perf calculation for amd_get_max

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Message-ID: <cb7e254f8def659a35481dc48d90d2b4391e21f5.1710473712.git.perry.yuan@amd.com>
Date: Fri, 15 Mar 2024 11:38:05 +0800
From: Perry Yuan <perry.yuan@....com>
To: <rafael.j.wysocki@...el.com>, <Mario.Limonciello@....com>,
	<viresh.kumar@...aro.org>, <Ray.Huang@....com>, <gautham.shenoy@....com>,
	<Borislav.Petkov@....com>
CC: <Alexander.Deucher@....com>, <Xinmei.Huang@....com>,
	<Xiaojian.Du@....com>, <Li.Meng@....com>, <linux-pm@...r.kernel.org>,
	<linux-kernel@...r.kernel.org>
Subject: [PATCH v5 4/8] cpufreq: amd-pstate: fix max_perf calculation for amd_get_max_freq()

From: Perry Yuan <Perry.Yuan@....com>

When CPU core Precision Boost state changed, the max frequency will also
need to be updated according to the current boost state, if boost is
disabled now, the max perf will be limited to nominal perf values.
otherwise the max frequency will be showed wrongly.

Signed-off-by: Perry Yuan <Perry.Yuan@....com>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@....com>
---
 drivers/cpufreq/amd-pstate.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 025f35bd3b01..a4bcac673fdb 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -676,6 +676,10 @@ static int amd_get_max_freq(struct amd_cpudata *cpudata)
 	nominal_perf = READ_ONCE(cpudata->nominal_perf);
 	max_perf = READ_ONCE(cpudata->highest_perf);
 
+	/* when boost is off, the highest perf will be limited to nominal_perf */
+	if (!amd_pstate_global_params.cpb_boost)
+		max_perf = nominal_perf;
+
 	boost_ratio = div_u64(max_perf << SCHED_CAPACITY_SHIFT,
 			      nominal_perf);
 
-- 
2.34.1