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From: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
To: rafael@kernel.org,
	viresh.kumar@linaro.org
Cc: linux-pm@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Subject: [PATCH] cpufreq: intel_pstate: Directly use stored ratios for max frequencies
Date: Thu, 18 Jan 2024 04:05:13 -0800
Message-Id: <20240118120513.1018808-1-srinivas.pandruvada@linux.intel.com>
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Avoid unnecessary calculation for converting frequency to performance
ratio by using a scaling factor for the maximum non turbo and turbo
frequency. Here the driver already stored performance ratios for max
non turbo and turbo frequency by reading from MSR_HWP_CAPABILITIES.
Directly use those ratios without any calculations.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/cpufreq/intel_pstate.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 2ca70b0b5fdc..6bbc21ca96e0 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -2532,7 +2532,14 @@ static void intel_pstate_update_perf_limits(struct cpudata *cpu,
 		int freq;
 
 		freq = max_policy_perf * perf_ctl_scaling;
-		max_policy_perf = DIV_ROUND_UP(freq, scaling);
+
+		if (freq == cpu->pstate.turbo_freq)
+			max_policy_perf = cpu->pstate.turbo_pstate;
+		else if (freq == cpu->pstate.max_freq)
+			max_policy_perf = cpu->pstate.max_pstate;
+		else
+			max_policy_perf = DIV_ROUND_UP(freq, scaling);
+
 		freq = min_policy_perf * perf_ctl_scaling;
 		min_policy_perf = DIV_ROUND_UP(freq, scaling);
 	}
-- 
2.40.1