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-rw-r--r--drivers/cpufreq/amd-pstate.c82
-rw-r--r--drivers/cpufreq/amd-pstate.h2
2 files changed, 71 insertions, 13 deletions
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 9a80040e3acf..fa4eb5a0a443 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -389,7 +389,8 @@ static inline int amd_pstate_cppc_enable(struct cpufreq_policy *policy)
static int msr_init_perf(struct amd_cpudata *cpudata)
{
union perf_cached perf = READ_ONCE(cpudata->perf);
- u64 cap1, numerator;
+ u64 cap1, numerator, cppc_req;
+ u8 min_perf;
int ret = rdmsrl_safe_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1,
&cap1);
@@ -400,6 +401,22 @@ static int msr_init_perf(struct amd_cpudata *cpudata)
if (ret)
return ret;
+ ret = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, &cppc_req);
+ if (ret)
+ return ret;
+
+ WRITE_ONCE(cpudata->cppc_req_cached, cppc_req);
+ min_perf = FIELD_GET(AMD_CPPC_MIN_PERF_MASK, cppc_req);
+
+ /*
+ * Clear out the min_perf part to check if the rest of the MSR is 0, if yes, this is an
+ * indication that the min_perf value is the one specified through the BIOS option
+ */
+ cppc_req &= ~(AMD_CPPC_MIN_PERF_MASK);
+
+ if (!cppc_req)
+ perf.bios_min_perf = min_perf;
+
perf.highest_perf = numerator;
perf.max_limit_perf = numerator;
perf.min_limit_perf = FIELD_GET(AMD_CPPC_LOWEST_PERF_MASK, cap1);
@@ -580,20 +597,26 @@ static int amd_pstate_verify(struct cpufreq_policy_data *policy_data)
{
/*
* Initialize lower frequency limit (i.e.policy->min) with
- * lowest_nonlinear_frequency which is the most energy efficient
- * frequency. Override the initial value set by cpufreq core and
- * amd-pstate qos_requests.
+ * lowest_nonlinear_frequency or the min frequency (if) specified in BIOS,
+ * Override the initial value set by cpufreq core and amd-pstate qos_requests.
*/
if (policy_data->min == FREQ_QOS_MIN_DEFAULT_VALUE) {
struct cpufreq_policy *policy __free(put_cpufreq_policy) =
cpufreq_cpu_get(policy_data->cpu);
struct amd_cpudata *cpudata;
+ union perf_cached perf;
if (!policy)
return -EINVAL;
cpudata = policy->driver_data;
- policy_data->min = cpudata->lowest_nonlinear_freq;
+ perf = READ_ONCE(cpudata->perf);
+
+ if (perf.bios_min_perf)
+ policy_data->min = perf_to_freq(perf, cpudata->nominal_freq,
+ perf.bios_min_perf);
+ else
+ policy_data->min = cpudata->lowest_nonlinear_freq;
}
cpufreq_verify_within_cpu_limits(policy_data);
@@ -1024,6 +1047,10 @@ free_cpudata1:
static void amd_pstate_cpu_exit(struct cpufreq_policy *policy)
{
struct amd_cpudata *cpudata = policy->driver_data;
+ union perf_cached perf = READ_ONCE(cpudata->perf);
+
+ /* Reset CPPC_REQ MSR to the BIOS value */
+ amd_pstate_update_perf(policy, perf.bios_min_perf, 0U, 0U, 0U, false);
freq_qos_remove_request(&cpudata->req[1]);
freq_qos_remove_request(&cpudata->req[0]);
@@ -1419,7 +1446,6 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
struct amd_cpudata *cpudata;
union perf_cached perf;
struct device *dev;
- u64 value;
int ret;
/*
@@ -1484,12 +1510,6 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
cpudata->epp_default = AMD_CPPC_EPP_BALANCE_PERFORMANCE;
}
- if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
- ret = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, &value);
- if (ret)
- return ret;
- WRITE_ONCE(cpudata->cppc_req_cached, value);
- }
ret = amd_pstate_set_epp(policy, cpudata->epp_default);
if (ret)
return ret;
@@ -1509,6 +1529,11 @@ static void amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy)
struct amd_cpudata *cpudata = policy->driver_data;
if (cpudata) {
+ union perf_cached perf = READ_ONCE(cpudata->perf);
+
+ /* Reset CPPC_REQ MSR to the BIOS value */
+ amd_pstate_update_perf(policy, perf.bios_min_perf, 0U, 0U, 0U, false);
+
kfree(cpudata);
policy->driver_data = NULL;
}
@@ -1566,12 +1591,31 @@ static int amd_pstate_cpu_online(struct cpufreq_policy *policy)
static int amd_pstate_cpu_offline(struct cpufreq_policy *policy)
{
- return 0;
+ struct amd_cpudata *cpudata = policy->driver_data;
+ union perf_cached perf = READ_ONCE(cpudata->perf);
+
+ /*
+ * Reset CPPC_REQ MSR to the BIOS value, this will allow us to retain the BIOS specified
+ * min_perf value across kexec reboots. If this CPU is just onlined normally after this, the
+ * limits, epp and desired perf will get reset to the cached values in cpudata struct
+ */
+ return amd_pstate_update_perf(policy, perf.bios_min_perf, 0U, 0U, 0U, false);
}
static int amd_pstate_suspend(struct cpufreq_policy *policy)
{
struct amd_cpudata *cpudata = policy->driver_data;
+ union perf_cached perf = READ_ONCE(cpudata->perf);
+ int ret;
+
+ /*
+ * Reset CPPC_REQ MSR to the BIOS value, this will allow us to retain the BIOS specified
+ * min_perf value across kexec reboots. If this CPU is just resumed back without kexec,
+ * the limits, epp and desired perf will get reset to the cached values in cpudata struct
+ */
+ ret = amd_pstate_update_perf(policy, perf.bios_min_perf, 0U, 0U, 0U, false);
+ if (ret)
+ return ret;
/* invalidate to ensure it's rewritten during resume */
cpudata->cppc_req_cached = 0;
@@ -1582,6 +1626,17 @@ static int amd_pstate_suspend(struct cpufreq_policy *policy)
return 0;
}
+static int amd_pstate_resume(struct cpufreq_policy *policy)
+{
+ struct amd_cpudata *cpudata = policy->driver_data;
+ union perf_cached perf = READ_ONCE(cpudata->perf);
+ int cur_perf = freq_to_perf(perf, cpudata->nominal_freq, policy->cur);
+
+ /* Set CPPC_REQ to last sane value until the governor updates it */
+ return amd_pstate_update_perf(policy, perf.min_limit_perf, cur_perf, perf.max_limit_perf,
+ 0U, false);
+}
+
static int amd_pstate_epp_resume(struct cpufreq_policy *policy)
{
struct amd_cpudata *cpudata = policy->driver_data;
@@ -1610,6 +1665,7 @@ static struct cpufreq_driver amd_pstate_driver = {
.online = amd_pstate_cpu_online,
.offline = amd_pstate_cpu_offline,
.suspend = amd_pstate_suspend,
+ .resume = amd_pstate_resume,
.set_boost = amd_pstate_set_boost,
.update_limits = amd_pstate_update_limits,
.name = "amd-pstate",
diff --git a/drivers/cpufreq/amd-pstate.h b/drivers/cpufreq/amd-pstate.h
index fbe1c08d3f06..2f7ae364d331 100644
--- a/drivers/cpufreq/amd-pstate.h
+++ b/drivers/cpufreq/amd-pstate.h
@@ -30,6 +30,7 @@
* @lowest_perf: the absolute lowest performance level of the processor
* @min_limit_perf: Cached value of the performance corresponding to policy->min
* @max_limit_perf: Cached value of the performance corresponding to policy->max
+ * @bios_min_perf: Cached perf value corresponding to the "Requested CPU Min Frequency" BIOS option
*/
union perf_cached {
struct {
@@ -39,6 +40,7 @@ union perf_cached {
u8 lowest_perf;
u8 min_limit_perf;
u8 max_limit_perf;
+ u8 bios_min_perf;
};
u64 val;
};