[v12,05/11] cpufreq: amd-pstate: implement amd pstate cpu online and offline callback
Commit Message
From: Perry Yuan <Perry.Yuan@amd.com>
Adds online and offline driver callback support to allow cpu cores go
offline and help to restore the previous working states when core goes
back online later for EPP driver mode.
Acked-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Mario Limonciello <Mario.Limonciello@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Tested-by: Wyes Karny <wyes.karny@amd.com>
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
---
drivers/cpufreq/amd-pstate.c | 82 ++++++++++++++++++++++++++++++++++++
include/linux/amd-pstate.h | 1 +
2 files changed, 83 insertions(+)
@@ -1000,6 +1000,86 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
return 0;
}
+static void amd_pstate_epp_reenable(struct amd_cpudata *cpudata)
+{
+ struct cppc_perf_ctrls perf_ctrls;
+ u64 value, max_perf;
+ int ret;
+
+ ret = amd_pstate_enable(true);
+ if (ret)
+ pr_err("failed to enable amd pstate during resume, return %d\n", ret);
+
+ value = READ_ONCE(cpudata->cppc_req_cached);
+ max_perf = READ_ONCE(cpudata->highest_perf);
+
+ if (boot_cpu_has(X86_FEATURE_CPPC)) {
+ wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
+ } else {
+ perf_ctrls.max_perf = max_perf;
+ perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(cpudata->epp_cached);
+ cppc_set_perf(cpudata->cpu, &perf_ctrls);
+ }
+}
+
+static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy)
+{
+ struct amd_cpudata *cpudata = policy->driver_data;
+
+ pr_debug("AMD CPU Core %d going online\n", cpudata->cpu);
+
+ if (cppc_state == AMD_PSTATE_ACTIVE) {
+ amd_pstate_epp_reenable(cpudata);
+ cpudata->suspended = false;
+ }
+
+ return 0;
+}
+
+static void amd_pstate_epp_offline(struct cpufreq_policy *policy)
+{
+ struct amd_cpudata *cpudata = policy->driver_data;
+ struct cppc_perf_ctrls perf_ctrls;
+ int min_perf;
+ u64 value;
+
+ min_perf = READ_ONCE(cpudata->lowest_perf);
+ value = READ_ONCE(cpudata->cppc_req_cached);
+
+ mutex_lock(&amd_pstate_limits_lock);
+ if (boot_cpu_has(X86_FEATURE_CPPC)) {
+ cpudata->epp_policy = CPUFREQ_POLICY_UNKNOWN;
+
+ /* Set max perf same as min perf */
+ value &= ~AMD_CPPC_MAX_PERF(~0L);
+ value |= AMD_CPPC_MAX_PERF(min_perf);
+ value &= ~AMD_CPPC_MIN_PERF(~0L);
+ value |= AMD_CPPC_MIN_PERF(min_perf);
+ wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
+ } else {
+ perf_ctrls.desired_perf = 0;
+ perf_ctrls.max_perf = min_perf;
+ perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(HWP_EPP_BALANCE_POWERSAVE);
+ cppc_set_perf(cpudata->cpu, &perf_ctrls);
+ }
+ mutex_unlock(&amd_pstate_limits_lock);
+}
+
+static int amd_pstate_epp_cpu_offline(struct cpufreq_policy *policy)
+{
+ struct amd_cpudata *cpudata = policy->driver_data;
+
+ pr_debug("AMD CPU Core %d going offline\n", cpudata->cpu);
+
+ if (cpudata->suspended)
+ return 0;
+
+ if (cppc_state == AMD_PSTATE_ACTIVE)
+ amd_pstate_epp_offline(policy);
+
+ return 0;
+}
+
static int amd_pstate_epp_verify_policy(struct cpufreq_policy_data *policy)
{
cpufreq_verify_within_cpu_limits(policy);
@@ -1026,6 +1106,8 @@ static struct cpufreq_driver amd_pstate_epp_driver = {
.setpolicy = amd_pstate_epp_set_policy,
.init = amd_pstate_epp_cpu_init,
.exit = amd_pstate_epp_cpu_exit,
+ .offline = amd_pstate_epp_cpu_offline,
+ .online = amd_pstate_epp_cpu_online,
.name = "amd_pstate_epp",
.attr = amd_pstate_epp_attr,
};
@@ -87,6 +87,7 @@ struct amd_cpudata {
s16 epp_cached;
u32 policy;
u64 cppc_cap1_cached;
+ bool suspended;
};
/*