Commit 41abd479 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

Merge tag 'amd-pstate-v6.16-2025-05-08' of... 

Merge tag 'amd-pstate-v6.16-2025-05-08' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/superm1/linux

Merge amd-pstate content for 6.16 (5/8/25) from Mario Limonciello:

 - Add support for a new feature on some BIOS that allows setting
   "lowest CPU minimum frequency".

 - Fix the amd-pstate-ut unit tests to restore system settings when
   done.

* tag 'amd-pstate-v6.16-2025-05-08' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/superm1/linux:
  amd-pstate-ut: Reset amd-pstate driver mode after running selftests
  cpufreq/amd-pstate: Add support for the "Requested CPU Min frequency" BIOS option
  cpufreq/amd-pstate: Add offline, online and suspend callbacks for amd_pstate_driver
  cpufreq/amd-pstate: Move max_perf limiting in amd_pstate_update
parents f1a50492 d26d1643

drivers/cpufreq/amd-pstate-ut.c

+12 −7
Original line number Diff line number Diff line
@@ -242,6 +242,8 @@ static int amd_pstate_set_mode(enum amd_pstate_mode mode) 
static int amd_pstate_ut_check_driver(u32 index)

{

	enum amd_pstate_mode mode1, mode2 = AMD_PSTATE_DISABLE;

	enum amd_pstate_mode orig_mode = amd_pstate_get_status();

	int ret;



	for (mode1 = AMD_PSTATE_DISABLE; mode1 < AMD_PSTATE_MAX; mode1++) {

		int ret = amd_pstate_set_mode(mode1);
@@ -251,16 +253,19 @@ static int amd_pstate_ut_check_driver(u32 index) 
			if (mode1 == mode2)

				continue;

			ret = amd_pstate_set_mode(mode2);

			if (ret) {

				pr_err("%s: failed to update status for %s->%s\n", __func__,

					amd_pstate_get_mode_string(mode1),

					amd_pstate_get_mode_string(mode2));

				return ret;

			}

			if (ret)

				goto out;

		}

	}



	return 0;

out:

	if (ret)

		pr_warn("%s: failed to update status for %s->%s: %d\n", __func__,

			amd_pstate_get_mode_string(mode1),

			amd_pstate_get_mode_string(mode2), ret);



	amd_pstate_set_mode(orig_mode);

	return ret;

}



static int __init amd_pstate_ut_init(void)

drivers/cpufreq/amd-pstate.c

+88 −25
Original line number Diff line number Diff line
@@ -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);
@@ -554,6 +571,10 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u8 min_perf, 
	if (!policy)

		return;



	/* limit the max perf when core performance boost feature is disabled */

	if (!cpudata->boost_supported)

		max_perf = min_t(u8, perf.nominal_perf, max_perf);



	des_perf = clamp_t(u8, des_perf, min_perf, max_perf);



	policy->cur = perf_to_freq(perf, cpudata->nominal_freq, des_perf);
@@ -563,10 +584,6 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u8 min_perf, 
		des_perf = 0;

	}



	/* limit the max perf when core performance boost feature is disabled */

	if (!cpudata->boost_supported)

		max_perf = min_t(u8, perf.nominal_perf, max_perf);



	if (trace_amd_pstate_perf_enabled() && amd_pstate_sample(cpudata)) {

		trace_amd_pstate_perf(min_perf, des_perf, max_perf, cpudata->freq,

			cpudata->cur.mperf, cpudata->cur.aperf, cpudata->cur.tsc,
@@ -580,19 +597,25 @@ 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;

		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;

	}
@@ -1021,6 +1044,10 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) 
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]);
@@ -1302,6 +1329,12 @@ static ssize_t amd_pstate_show_status(char *buf) 
	return sysfs_emit(buf, "%s\n", amd_pstate_mode_string[cppc_state]);

}



int amd_pstate_get_status(void)

{

	return cppc_state;

}

EXPORT_SYMBOL_GPL(amd_pstate_get_status);



int amd_pstate_update_status(const char *buf, size_t size)

{

	int mode_idx;
@@ -1416,7 +1449,6 @@ 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;



	/*
@@ -1481,12 +1513,6 @@ 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;
@@ -1506,6 +1532,11 @@ 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;

	}
@@ -1556,21 +1587,38 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) 
	return 0;

}



static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy)

static int amd_pstate_cpu_online(struct cpufreq_policy *policy)

{

	pr_debug("AMD CPU Core %d going online\n", policy->cpu);



	return amd_pstate_cppc_enable(policy);

}



static int amd_pstate_epp_cpu_offline(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_epp_suspend(struct cpufreq_policy *policy)

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;
@@ -1581,6 +1629,17 @@ static int amd_pstate_epp_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;
@@ -1606,6 +1665,10 @@ static struct cpufreq_driver amd_pstate_driver = { 
	.fast_switch    = amd_pstate_fast_switch,

	.init		= amd_pstate_cpu_init,

	.exit		= amd_pstate_cpu_exit,

	.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",
@@ -1618,9 +1681,9 @@ 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,

	.suspend	= amd_pstate_epp_suspend,

	.offline	= amd_pstate_cpu_offline,

	.online		= amd_pstate_cpu_online,

	.suspend	= amd_pstate_suspend,

	.resume		= amd_pstate_epp_resume,

	.update_limits	= amd_pstate_update_limits,

	.set_boost	= amd_pstate_set_boost,

drivers/cpufreq/amd-pstate.h

+3 −0
Original line number Diff line number Diff line
@@ -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;

};
@@ -119,6 +121,7 @@ enum amd_pstate_mode { 
	AMD_PSTATE_MAX,

};

const char *amd_pstate_get_mode_string(enum amd_pstate_mode mode);

int amd_pstate_get_status(void);

int amd_pstate_update_status(const char *buf, size_t size);



#endif /* _LINUX_AMD_PSTATE_H */