linux-kernel - [PATCH 2/4] cpufreq/amd-pstate: Don't update CPPC request in amd_pstate_cpu_boost

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Message-ID: <20241012174519.897-2-mario.limonciello@amd.com>
Date: Sat, 12 Oct 2024 12:45:17 -0500
From: Mario Limonciello <mario.limonciello@....com>
To: "Gautham R . Shenoy" <gautham.shenoy@....com>
CC: Perry Yuan <perry.yuan@....com>, <linux-kernel@...r.kernel.org>,
	<linux-pm@...r.kernel.org>, Dhananjay Ugwekar <Dhananjay.Ugwekar@....com>,
	Mario Limonciello <mario.limonciello@....com>
Subject: [PATCH 2/4] cpufreq/amd-pstate: Don't update CPPC request in amd_pstate_cpu_boost_update()

When boost is changed the CPPC value is changed in amd_pstate_cpu_boost_update()
but then changed again when refresh_frequency_limits() and all it's callbacks
occur.  The first is a pointless write, so instead just update the limits for
the policy and let the policy refresh anchor everything properly.

Fixes: c8c68c38b56f ("cpufreq: amd-pstate: initialize core precision boost state")
Signed-off-by: Mario Limonciello <mario.limonciello@....com>
---
 drivers/cpufreq/amd-pstate.c | 24 +-----------------------
 1 file changed, 1 insertion(+), 23 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index dfa9a146769b..13dec8b1e7a8 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -665,34 +665,12 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
 static int amd_pstate_cpu_boost_update(struct cpufreq_policy *policy, bool on)
 {
 	struct amd_cpudata *cpudata = policy->driver_data;
-	struct cppc_perf_ctrls perf_ctrls;
-	u32 highest_perf, nominal_perf, nominal_freq, max_freq;
+	u32 nominal_freq, max_freq;
 	int ret = 0;
 
-	highest_perf = READ_ONCE(cpudata->highest_perf);
-	nominal_perf = READ_ONCE(cpudata->nominal_perf);
 	nominal_freq = READ_ONCE(cpudata->nominal_freq);
 	max_freq = READ_ONCE(cpudata->max_freq);
 
-	if (boot_cpu_has(X86_FEATURE_CPPC)) {
-		u64 value = READ_ONCE(cpudata->cppc_req_cached);
-
-		value &= ~GENMASK_ULL(7, 0);
-		value |= on ? highest_perf : nominal_perf;
-		WRITE_ONCE(cpudata->cppc_req_cached, value);
-
-		wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
-	} else {
-		perf_ctrls.max_perf = on ? highest_perf : nominal_perf;
-		ret = cppc_set_perf(cpudata->cpu, &perf_ctrls);
-		if (ret) {
-			cpufreq_cpu_release(policy);
-			pr_debug("Failed to set max perf on CPU:%d. ret:%d\n",
-				cpudata->cpu, ret);
-			return ret;
-		}
-	}
-
 	if (on)
 		policy->cpuinfo.max_freq = max_freq;
 	else if (policy->cpuinfo.max_freq > nominal_freq * 1000)
-- 
2.43.0