[PATCH v3 3/7] cpufreq: amd-pstate: fix max_perf calculation for amd_get_max_freq()

Perry Yuan
2024-02-07T09:22:43Z

From: Perry Yuan <Perry.Yuan@amd.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@amd.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 82b43bb2ab83..1f86ce920d6c 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -624,6 +624,10 @@ 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 (!global.cpb_boost)
+ max_perf = nominal_perf;
+
boost_ratio = div_u64(max_perf << SCHED_CAPACITY_SHIFT,
nominal_perf);

--
2.34.1