[PATCH 2/4] cpufreq/amd-pstate: Don't update CPPC request in amd_pstate_cpu_boost_update()

From: Mario Limonciello
Date: Sat Oct 12 2024 - 13:46:13 EST


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@xxxxxxx>
---
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