linux-kernel - [PATCH] cpufreq/amd-pstate: Refactor max frequency calculation

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Message-ID: <20241218190030.1228868-1-naresh.solanki@9elements.com>
Date: Thu, 19 Dec 2024 00:30:29 +0530
From: Naresh Solanki <naresh.solanki@...ements.com>
To: Huang Rui <ray.huang@....com>,
	"Gautham R. Shenoy" <gautham.shenoy@....com>,
	Mario Limonciello <mario.limonciello@....com>,
	Perry Yuan <perry.yuan@....com>,
	"Rafael J. Wysocki" <rafael@...nel.org>,
	Viresh Kumar <viresh.kumar@...aro.org>,
	linux-pm@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: Naresh Solanki <naresh.solanki@...ements.com>
Subject: [PATCH] cpufreq/amd-pstate: Refactor max frequency calculation

Refactor to calculate max-freq more accurately.

Signed-off-by: Naresh Solanki <naresh.solanki@...ements.com>
---
 drivers/cpufreq/amd-pstate.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index d7630bab2516..78a2cbd14952 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -892,7 +892,7 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata)
 	u64 numerator;
 	u32 nominal_perf, nominal_freq;
 	u32 lowest_nonlinear_perf, lowest_nonlinear_freq;
-	u32 boost_ratio, lowest_nonlinear_ratio;
+	u32 lowest_nonlinear_ratio;
 	struct cppc_perf_caps cppc_perf;
 
 	ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
@@ -914,8 +914,7 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata)
 	ret = amd_get_boost_ratio_numerator(cpudata->cpu, &numerator);
 	if (ret)
 		return ret;
-	boost_ratio = div_u64(numerator << SCHED_CAPACITY_SHIFT, nominal_perf);
-	max_freq = (nominal_freq * boost_ratio >> SCHED_CAPACITY_SHIFT) * 1000;
+	max_freq = div_u64(numerator * nominal_freq * 1000, nominal_perf);
 
 	lowest_nonlinear_perf = READ_ONCE(cpudata->lowest_nonlinear_perf);
 	lowest_nonlinear_ratio = div_u64(lowest_nonlinear_perf << SCHED_CAPACITY_SHIFT,
-- 
2.42.0