From: Perry Yuan <[email protected]>
Add EPP driver support for AMD SoCs which support a dedicated MSR for
CPPC. EPP is used by the DPM controller to configure the frequency that
a core operates at during short periods of activity.
The SoC EPP targets are configured on a scale from 0 to 255 where 0
represents maximum performance and 255 represents maximum efficiency.
The amd-pstate driver exports profile string names to userspace that are
tied to specific EPP values.
The balance_performance string (0x80) provides the best balance for
efficiency versus power on most systems, but users can choose other
strings to meet their needs as well.
$ cat /sys/devices/system/cpu/cpufreq/policy0/energy_performance_available_preferences
default performance balance_performance balance_power power
$ cat /sys/devices/system/cpu/cpufreq/policy0/energy_performance_preference
balance_performance
To enable the driver,it needs to add `amd_pstate=active` to kernel
command line and kernel will load the active mode epp driver
Signed-off-by: Perry Yuan <[email protected]>
---
drivers/cpufreq/amd-pstate.c | 643 ++++++++++++++++++++++++++++++++++-
include/linux/amd-pstate.h | 35 ++
2 files changed, 672 insertions(+), 6 deletions(-)
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 204e39006dda..5989d4d25d0f 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -37,9 +37,12 @@
#include <linux/uaccess.h>
#include <linux/static_call.h>
#include <linux/amd-pstate.h>
+#include <linux/cpufreq_common.h>
+#ifdef CONFIG_ACPI
#include <acpi/processor.h>
#include <acpi/cppc_acpi.h>
+#endif
#include <asm/msr.h>
#include <asm/processor.h>
@@ -59,9 +62,130 @@
* we disable it by default to go acpi-cpufreq on these processors and add a
* module parameter to be able to enable it manually for debugging.
*/
-static struct cpufreq_driver amd_pstate_driver;
+static bool cppc_active;
static int cppc_load __initdata;
+static struct cpufreq_driver *default_pstate_driver;
+static struct amd_cpudata **all_cpu_data;
+static struct amd_pstate_params global_params;
+
+static DEFINE_MUTEX(amd_pstate_limits_lock);
+static DEFINE_MUTEX(amd_pstate_driver_lock);
+
+static bool cppc_boost __read_mostly;
+struct kobject *amd_pstate_kobj;
+
+#ifdef CONFIG_ACPI_CPPC_LIB
+static s16 amd_pstate_get_epp(struct amd_cpudata *cpudata, u64 cppc_req_cached)
+{
+ s16 epp;
+ struct cppc_perf_caps perf_caps;
+ int ret;
+
+ if (boot_cpu_has(X86_FEATURE_CPPC)) {
+ if (!cppc_req_cached) {
+ epp = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ,
+ &cppc_req_cached);
+ if (epp)
+ return epp;
+ }
+ epp = (cppc_req_cached >> 24) & 0xFF;
+ } else {
+ ret = cppc_get_epp_caps(cpudata->cpu, &perf_caps);
+ if (ret < 0) {
+ pr_debug("Could not retrieve energy perf value (%d)\n", ret);
+ return -EIO;
+ }
+ epp = (s16) perf_caps.energy_perf;
+ }
+
+ return epp;
+}
+#endif
+
+static int amd_pstate_get_energy_pref_index(struct amd_cpudata *cpudata)
+{
+ s16 epp;
+ int index = -EINVAL;
+
+ epp = amd_pstate_get_epp(cpudata, 0);
+ if (epp < 0)
+ return epp;
+
+ switch (epp) {
+ case HWP_EPP_PERFORMANCE:
+ index = EPP_INDEX_PERFORMANCE;
+ break;
+ case HWP_EPP_BALANCE_PERFORMANCE:
+ index = EPP_INDEX_BALANCE_PERFORMANCE;
+ break;
+ case HWP_EPP_BALANCE_POWERSAVE:
+ index = EPP_INDEX_BALANCE_POWERSAVE;
+ break;
+ case HWP_EPP_POWERSAVE:
+ index = EPP_INDEX_POWERSAVE;
+ break;
+ default:
+ break;
+ }
+
+ return index;
+}
+
+#ifdef CONFIG_ACPI_CPPC_LIB
+static int amd_pstate_set_epp(struct amd_cpudata *cpudata, u32 epp)
+{
+ int ret;
+ struct cppc_perf_ctrls perf_ctrls;
+
+ if (boot_cpu_has(X86_FEATURE_CPPC)) {
+ u64 value = READ_ONCE(cpudata->cppc_req_cached);
+
+ value &= ~GENMASK_ULL(31, 24);
+ value |= (u64)epp << 24;
+ WRITE_ONCE(cpudata->cppc_req_cached, value);
+
+ ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
+ if (!ret)
+ cpudata->epp_cached = epp;
+ } else {
+ perf_ctrls.energy_perf = epp;
+ ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
+ if (ret) {
+ pr_debug("failed to set energy perf value (%d)\n", ret);
+ return ret;
+ }
+ cpudata->epp_cached = epp;
+ }
+
+ return ret;
+}
+
+static int amd_pstate_set_energy_pref_index(struct amd_cpudata *cpudata,
+ int pref_index)
+{
+ int epp = -EINVAL;
+ int ret;
+
+ if (!pref_index) {
+ pr_debug("EPP pref_index is invalid\n");
+ return -EINVAL;
+ }
+
+ if (epp == -EINVAL)
+ epp = epp_values[pref_index];
+
+ if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
+ pr_debug("EPP cannot be set under performance policy\n");
+ return -EBUSY;
+ }
+
+ ret = amd_pstate_set_epp(cpudata, epp);
+
+ return ret;
+}
+#endif
+
static inline int pstate_enable(bool enable)
{
return wrmsrl_safe(MSR_AMD_CPPC_ENABLE, enable);
@@ -70,11 +194,21 @@ static inline int pstate_enable(bool enable)
static int cppc_enable(bool enable)
{
int cpu, ret = 0;
+ struct cppc_perf_ctrls perf_ctrls;
for_each_present_cpu(cpu) {
ret = cppc_set_enable(cpu, enable);
if (ret)
return ret;
+
+ /* Enable autonomous mode for EPP */
+ if (!cppc_active) {
+ /* Set desired perf as zero to allow EPP firmware control */
+ perf_ctrls.desired_perf = 0;
+ ret = cppc_set_perf(cpu, &perf_ctrls);
+ if (ret)
+ return ret;
+ }
}
return ret;
@@ -417,7 +551,7 @@ static void amd_pstate_boost_init(struct amd_cpudata *cpudata)
return;
cpudata->boost_supported = true;
- amd_pstate_driver.boost_enabled = true;
+ default_pstate_driver->boost_enabled = true;
}
static void amd_perf_ctl_reset(unsigned int cpu)
@@ -591,10 +725,61 @@ static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy *policy,
return sprintf(&buf[0], "%u\n", perf);
}
+static ssize_t show_energy_performance_available_preferences(
+ struct cpufreq_policy *policy, char *buf)
+{
+ int i = 0;
+ int ret = 0;
+
+ while (energy_perf_strings[i] != NULL)
+ ret += sysfs_emit(buf, "%s", energy_perf_strings[i++]);
+
+ ret += sysfs_emit(buf, "\n");
+
+ return ret;
+}
+
+static ssize_t store_energy_performance_preference(
+ struct cpufreq_policy *policy, const char *buf, size_t count)
+{
+ struct amd_cpudata *cpudata = policy->driver_data;
+ char str_preference[21];
+ ssize_t ret;
+
+ ret = sscanf(buf, "%20s", str_preference);
+ if (ret != 1)
+ return -EINVAL;
+
+ ret = match_string(energy_perf_strings, -1, str_preference);
+ if (ret < 0)
+ return -EINVAL;
+
+ mutex_lock(&amd_pstate_limits_lock);
+ ret = amd_pstate_set_energy_pref_index(cpudata, ret);
+ mutex_unlock(&amd_pstate_limits_lock);
+
+ return ret ?: count;
+}
+
+static ssize_t show_energy_performance_preference(
+ struct cpufreq_policy *policy, char *buf)
+{
+ struct amd_cpudata *cpudata = policy->driver_data;
+ int preference;
+
+ preference = amd_pstate_get_energy_pref_index(cpudata);
+ if (preference < 0)
+ return preference;
+
+ return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]);
+}
+
cpufreq_freq_attr_ro(amd_pstate_max_freq);
cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
cpufreq_freq_attr_ro(amd_pstate_highest_perf);
+cpufreq_freq_attr_rw(energy_performance_preference);
+cpufreq_freq_attr_ro(energy_performance_available_preferences);
static struct freq_attr *amd_pstate_attr[] = {
&amd_pstate_max_freq,
@@ -603,6 +788,429 @@ static struct freq_attr *amd_pstate_attr[] = {
NULL,
};
+static struct freq_attr *amd_pstate_epp_attr[] = {
+ &amd_pstate_max_freq,
+ &amd_pstate_lowest_nonlinear_freq,
+ &amd_pstate_highest_perf,
+ &energy_performance_preference,
+ &energy_performance_available_preferences,
+ NULL,
+};
+
+static inline void update_boost_state(void)
+{
+ u64 misc_en;
+ struct amd_cpudata *cpudata;
+
+ cpudata = all_cpu_data[0];
+ rdmsrl(MSR_K7_HWCR, misc_en);
+ global_params.cppc_boost_disabled = misc_en & BIT_ULL(25);
+}
+
+static bool amd_pstate_acpi_pm_profile_server(void)
+{
+ if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
+ acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
+ return true;
+
+ return false;
+}
+
+static int amd_pstate_init_cpu(unsigned int cpunum)
+{
+ struct amd_cpudata *cpudata;
+
+ cpudata = all_cpu_data[cpunum];
+ if (!cpudata) {
+ cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL);
+ if (!cpudata)
+ return -ENOMEM;
+ WRITE_ONCE(all_cpu_data[cpunum], cpudata);
+
+ cpudata->cpu = cpunum;
+
+ if (cppc_active) {
+ if (amd_pstate_acpi_pm_profile_server())
+ cppc_boost = true;
+ }
+
+ }
+ cpudata->epp_powersave = -EINVAL;
+ cpudata->epp_policy = 0;
+ pr_debug("controlling: cpu %d\n", cpunum);
+ return 0;
+}
+
+static int __amd_pstate_cpu_init(struct cpufreq_policy *policy)
+{
+ int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
+ struct amd_cpudata *cpudata;
+ struct device *dev;
+ int rc;
+ u64 value;
+
+ rc = amd_pstate_init_cpu(policy->cpu);
+ if (rc)
+ return rc;
+
+ cpudata = all_cpu_data[policy->cpu];
+
+ dev = get_cpu_device(policy->cpu);
+ if (!dev)
+ goto free_cpudata1;
+
+ rc = amd_pstate_init_perf(cpudata);
+ if (rc)
+ goto free_cpudata1;
+
+ min_freq = amd_get_min_freq(cpudata);
+ max_freq = amd_get_max_freq(cpudata);
+ nominal_freq = amd_get_nominal_freq(cpudata);
+ lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
+ if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
+ dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
+ min_freq, max_freq);
+ ret = -EINVAL;
+ goto free_cpudata1;
+ }
+
+ policy->min = min_freq;
+ policy->max = max_freq;
+
+ policy->cpuinfo.min_freq = min_freq;
+ policy->cpuinfo.max_freq = max_freq;
+ /* It will be updated by governor */
+ policy->cur = policy->cpuinfo.min_freq;
+
+ /* Initial processor data capability frequencies */
+ cpudata->max_freq = max_freq;
+ cpudata->min_freq = min_freq;
+ cpudata->nominal_freq = nominal_freq;
+ cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
+
+ policy->driver_data = cpudata;
+
+ update_boost_state();
+ cpudata->epp_cached = amd_pstate_get_epp(cpudata, value);
+
+ policy->min = policy->cpuinfo.min_freq;
+ policy->max = policy->cpuinfo.max_freq;
+
+ if (boot_cpu_has(X86_FEATURE_CPPC))
+ policy->fast_switch_possible = true;
+
+ if (boot_cpu_has(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 = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1, &value);
+ if (ret)
+ return ret;
+ WRITE_ONCE(cpudata->cppc_cap1_cached, value);
+ }
+ amd_pstate_boost_init(cpudata);
+
+ return 0;
+
+free_cpudata1:
+ kfree(cpudata);
+ return ret;
+}
+
+static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ ret = __amd_pstate_cpu_init(policy);
+ if (ret)
+ return ret;
+ /*
+ * Set the policy to powersave to provide a valid fallback value in case
+ * the default cpufreq governor is neither powersave nor performance.
+ */
+ policy->policy = CPUFREQ_POLICY_POWERSAVE;
+
+ return 0;
+}
+
+static int amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy)
+{
+ pr_debug("CPU %d exiting\n", policy->cpu);
+ policy->fast_switch_possible = false;
+ return 0;
+}
+
+static void amd_pstate_update_max_freq(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = policy = cpufreq_cpu_get(cpu);
+
+ if (!policy)
+ return;
+
+ refresh_frequency_limits(policy);
+ cpufreq_cpu_put(policy);
+}
+
+static void amd_pstate_epp_update_limits(unsigned int cpu)
+{
+ mutex_lock(&amd_pstate_driver_lock);
+ update_boost_state();
+ if (global_params.cppc_boost_disabled) {
+ for_each_possible_cpu(cpu)
+ amd_pstate_update_max_freq(cpu);
+ } else {
+ cpufreq_update_policy(cpu);
+ }
+ mutex_unlock(&amd_pstate_driver_lock);
+}
+
+static int cppc_boost_hold_time_ns = 3 * NSEC_PER_MSEC;
+
+static inline void amd_pstate_boost_up(struct amd_cpudata *cpudata)
+{
+ u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
+ u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
+ u32 max_limit = (hwp_req & 0xff);
+ u32 min_limit = (hwp_req & 0xff00) >> 8;
+ u32 boost_level1;
+
+ /* If max and min are equal or already at max, nothing to boost */
+ if (max_limit == min_limit)
+ return;
+
+ /* Set boost max and min to initial value */
+ if (!cpudata->cppc_boost_min)
+ cpudata->cppc_boost_min = min_limit;
+
+ boost_level1 = ((AMD_CPPC_NOMINAL_PERF(hwp_cap) + min_limit) >> 1);
+
+ if (cpudata->cppc_boost_min < boost_level1)
+ cpudata->cppc_boost_min = boost_level1;
+ else if (cpudata->cppc_boost_min < AMD_CPPC_NOMINAL_PERF(hwp_cap))
+ cpudata->cppc_boost_min = AMD_CPPC_NOMINAL_PERF(hwp_cap);
+ else if (cpudata->cppc_boost_min == AMD_CPPC_NOMINAL_PERF(hwp_cap))
+ cpudata->cppc_boost_min = max_limit;
+ else
+ return;
+
+ hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
+ hwp_req |= AMD_CPPC_MIN_PERF(cpudata->cppc_boost_min);
+ wrmsrl(MSR_AMD_CPPC_REQ, hwp_req);
+ cpudata->last_update = cpudata->sample.time;
+}
+
+static inline void amd_pstate_boost_down(struct amd_cpudata *cpudata)
+{
+ bool expired;
+
+ if (cpudata->cppc_boost_min) {
+ expired = time_after64(cpudata->sample.time, cpudata->last_update +
+ cppc_boost_hold_time_ns);
+
+ if (expired) {
+ wrmsrl(MSR_AMD_CPPC_REQ, cpudata->cppc_req_cached);
+ cpudata->cppc_boost_min = 0;
+ }
+ }
+
+ cpudata->last_update = cpudata->sample.time;
+}
+
+static inline void amd_pstate_boost_update_util(struct amd_cpudata *cpudata,
+ u64 time)
+{
+ cpudata->sample.time = time;
+ if (smp_processor_id() != cpudata->cpu)
+ return;
+
+ if (cpudata->sched_flags & SCHED_CPUFREQ_IOWAIT) {
+ bool do_io = false;
+
+ cpudata->sched_flags = 0;
+ /*
+ * Set iowait_boost flag and update time. Since IO WAIT flag
+ * is set all the time, we can't just conclude that there is
+ * some IO bound activity is scheduled on this CPU with just
+ * one occurrence. If we receive at least two in two
+ * consecutive ticks, then we treat as boost candidate.
+ * This is leveraged from Intel Pstate driver.
+ */
+ if (time_before64(time, cpudata->last_io_update + 2 * TICK_NSEC))
+ do_io = true;
+
+ cpudata->last_io_update = time;
+
+ if (do_io)
+ amd_pstate_boost_up(cpudata);
+
+ } else {
+ amd_pstate_boost_down(cpudata);
+ }
+}
+
+static inline void amd_pstate_cppc_update_hook(struct update_util_data *data,
+ u64 time, unsigned int flags)
+{
+ struct amd_cpudata *cpudata = container_of(data,
+ struct amd_cpudata, update_util);
+
+ cpudata->sched_flags |= flags;
+
+ if (smp_processor_id() == cpudata->cpu)
+ amd_pstate_boost_update_util(cpudata, time);
+}
+
+static void amd_pstate_clear_update_util_hook(unsigned int cpu)
+{
+ struct amd_cpudata *cpudata = all_cpu_data[cpu];
+
+ if (!cpudata->update_util_set)
+ return;
+
+ cpufreq_remove_update_util_hook(cpu);
+ cpudata->update_util_set = false;
+ synchronize_rcu();
+}
+
+static void amd_pstate_set_update_util_hook(unsigned int cpu_num)
+{
+ struct amd_cpudata *cpudata = all_cpu_data[cpu_num];
+
+ if (!cppc_boost) {
+ if (cpudata->update_util_set)
+ amd_pstate_clear_update_util_hook(cpudata->cpu);
+ return;
+ }
+
+ if (cpudata->update_util_set)
+ return;
+
+ cpudata->sample.time = 0;
+ cpufreq_add_update_util_hook(cpu_num, &cpudata->update_util,
+ amd_pstate_cppc_update_hook);
+ cpudata->update_util_set = true;
+}
+
+static void amd_pstate_epp_init(unsigned int cpu)
+{
+ struct amd_cpudata *cpudata = all_cpu_data[cpu];
+ u32 max_perf, min_perf;
+ u64 value;
+ s16 epp;
+ int ret;
+
+ max_perf = READ_ONCE(cpudata->highest_perf);
+ min_perf = READ_ONCE(cpudata->lowest_perf);
+
+ value = READ_ONCE(cpudata->cppc_req_cached);
+
+ if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
+ min_perf = max_perf;
+
+ /* Initial min/max values for CPPC Performance Controls Register */
+ value &= ~AMD_CPPC_MIN_PERF(~0L);
+ value |= AMD_CPPC_MIN_PERF(min_perf);
+
+ value &= ~AMD_CPPC_MAX_PERF(~0L);
+ value |= AMD_CPPC_MAX_PERF(max_perf);
+
+ /* CPPC EPP feature require to set zero to the desire perf bit */
+ value &= ~AMD_CPPC_DES_PERF(~0L);
+ value |= AMD_CPPC_DES_PERF(0);
+
+ if (cpudata->epp_policy == cpudata->policy)
+ goto skip_epp;
+
+ cpudata->epp_policy = cpudata->policy;
+
+ if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
+ epp = amd_pstate_get_epp(cpudata, value);
+ cpudata->epp_powersave = epp;
+ if (epp < 0)
+ goto skip_epp;
+ /* force the epp value to be zero for performance policy */
+ epp = 0;
+ } else {
+ if (cpudata->epp_powersave < 0)
+ goto skip_epp;
+ /* Get BIOS pre-defined epp value */
+ epp = amd_pstate_get_epp(cpudata, value);
+ if (epp)
+ goto skip_epp;
+ epp = cpudata->epp_powersave;
+ }
+ /* Set initial EPP value */
+ if (boot_cpu_has(X86_FEATURE_CPPC)) {
+ value &= ~GENMASK_ULL(31, 24);
+ value |= (u64)epp << 24;
+ }
+
+skip_epp:
+ WRITE_ONCE(cpudata->cppc_req_cached, value);
+ ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
+ if (!ret)
+ cpudata->epp_cached = epp;
+}
+
+static void amd_pstate_set_max_limits(struct amd_cpudata *cpudata)
+{
+ u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
+ u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
+ u32 max_limit = (hwp_cap >> 24) & 0xff;
+
+ hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
+ hwp_req |= AMD_CPPC_MIN_PERF(max_limit);
+ wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, hwp_req);
+}
+
+static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
+{
+ struct amd_cpudata *cpudata;
+
+ if (!policy->cpuinfo.max_freq)
+ return -ENODEV;
+
+ pr_debug("set_policy: cpuinfo.max %u policy->max %u\n",
+ policy->cpuinfo.max_freq, policy->max);
+
+ cpudata = all_cpu_data[policy->cpu];
+ cpudata->policy = policy->policy;
+
+ if (boot_cpu_has(X86_FEATURE_CPPC)) {
+ mutex_lock(&amd_pstate_limits_lock);
+
+ if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
+ amd_pstate_clear_update_util_hook(policy->cpu);
+ amd_pstate_set_max_limits(cpudata);
+ } else {
+ amd_pstate_set_update_util_hook(policy->cpu);
+ }
+
+ if (boot_cpu_has(X86_FEATURE_CPPC))
+ amd_pstate_epp_init(policy->cpu);
+
+ mutex_unlock(&amd_pstate_limits_lock);
+ }
+
+ return 0;
+}
+
+static void amd_pstate_verify_cpu_policy(struct amd_cpudata *cpudata,
+ struct cpufreq_policy_data *policy)
+{
+ update_boost_state();
+ cpufreq_verify_within_cpu_limits(policy);
+}
+
+static int amd_pstate_epp_verify_policy(struct cpufreq_policy_data *policy)
+{
+ amd_pstate_verify_cpu_policy(all_cpu_data[policy->cpu], policy);
+ pr_debug("policy_max =%d, policy_min=%d\n", policy->max, policy->min);
+ return 0;
+}
+
static struct cpufreq_driver amd_pstate_driver = {
.flags = CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_UPDATE_LIMITS,
.verify = amd_pstate_verify,
@@ -616,8 +1224,20 @@ static struct cpufreq_driver amd_pstate_driver = {
.attr = amd_pstate_attr,
};
+static struct cpufreq_driver amd_pstate_epp_driver = {
+ .flags = CPUFREQ_CONST_LOOPS,
+ .verify = amd_pstate_epp_verify_policy,
+ .setpolicy = amd_pstate_epp_set_policy,
+ .init = amd_pstate_epp_cpu_init,
+ .exit = amd_pstate_epp_cpu_exit,
+ .update_limits = amd_pstate_epp_update_limits,
+ .name = "amd_pstate_epp",
+ .attr = amd_pstate_epp_attr,
+};
+
static int __init amd_pstate_init(void)
{
+ static struct amd_cpudata **cpudata;
int ret;
if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
@@ -644,7 +1264,8 @@ static int __init amd_pstate_init(void)
/* capability check */
if (boot_cpu_has(X86_FEATURE_CPPC)) {
pr_debug("AMD CPPC MSR based functionality is supported\n");
- amd_pstate_driver.adjust_perf = amd_pstate_adjust_perf;
+ if (!cppc_active)
+ default_pstate_driver->adjust_perf = amd_pstate_adjust_perf;
} else {
pr_debug("AMD CPPC shared memory based functionality is supported\n");
static_call_update(amd_pstate_enable, cppc_enable);
@@ -652,6 +1273,10 @@ static int __init amd_pstate_init(void)
static_call_update(amd_pstate_update_perf, cppc_update_perf);
}
+ cpudata = vzalloc(array_size(sizeof(void *), num_possible_cpus()));
+ if (!cpudata)
+ return -ENOMEM;
+ WRITE_ONCE(all_cpu_data, cpudata);
/* enable amd pstate feature */
ret = amd_pstate_enable(true);
if (ret) {
@@ -659,9 +1284,9 @@ static int __init amd_pstate_init(void)
return ret;
}
- ret = cpufreq_register_driver(&amd_pstate_driver);
+ ret = cpufreq_register_driver(default_pstate_driver);
if (ret)
- pr_err("failed to register amd_pstate_driver with return %d\n",
+ pr_err("failed to register amd pstate driver with return %d\n",
ret);
return ret;
@@ -676,8 +1301,14 @@ static int __init amd_pstate_param(char *str)
if (!strcmp(str, "disable")) {
cppc_load = 0;
pr_info("driver is explicitly disabled\n");
- } else if (!strcmp(str, "passive"))
+ } else if (!strcmp(str, "passive")) {
cppc_load = 1;
+ default_pstate_driver = &amd_pstate_driver;
+ } else if (!strcmp(str, "active")) {
+ cppc_active = 1;
+ cppc_load = 1;
+ default_pstate_driver = &amd_pstate_epp_driver;
+ }
return 0;
}
diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
index 1c4b8659f171..888af62040f1 100644
--- a/include/linux/amd-pstate.h
+++ b/include/linux/amd-pstate.h
@@ -25,6 +25,7 @@ struct amd_aperf_mperf {
u64 aperf;
u64 mperf;
u64 tsc;
+ u64 time;
};
/**
@@ -47,6 +48,18 @@ struct amd_aperf_mperf {
* @prev: Last Aperf/Mperf/tsc count value read from register
* @freq: current cpu frequency value
* @boost_supported: check whether the Processor or SBIOS supports boost mode
+ * @epp_powersave: Last saved CPPC energy performance preference
+ when policy switched to performance
+ * @epp_policy: Last saved policy used to set energy-performance preference
+ * @epp_cached: Cached CPPC energy-performance preference value
+ * @policy: Cpufreq policy value
+ * @sched_flags: Store scheduler flags for possible cross CPU update
+ * @update_util_set: CPUFreq utility callback is set
+ * @last_update: Time stamp of the last performance state update
+ * @cppc_boost_min: Last CPPC boosted min performance state
+ * @cppc_cap1_cached: Cached value of the last CPPC Capabilities MSR
+ * @update_util: Cpufreq utility callback information
+ * @sample: the stored performance sample
*
* The amd_cpudata is key private data for each CPU thread in AMD P-State, and
* represents all the attributes and goals that AMD P-State requests at runtime.
@@ -72,6 +85,28 @@ struct amd_cpudata {
u64 freq;
bool boost_supported;
+
+ /* EPP feature related attributes*/
+ s16 epp_powersave;
+ s16 epp_policy;
+ s16 epp_cached;
+ u32 policy;
+ u32 sched_flags;
+ bool update_util_set;
+ u64 last_update;
+ u64 last_io_update;
+ u32 cppc_boost_min;
+ u64 cppc_cap1_cached;
+ struct update_util_data update_util;
+ struct amd_aperf_mperf sample;
+};
+
+/**
+ * struct amd_pstate_params - global parameters for the performance control
+ * @ cppc_boost_disabled wheher the core performance boost disabled
+ */
+struct amd_pstate_params {
+ bool cppc_boost_disabled;
};
#endif /* _LINUX_AMD_PSTATE_H */
--
2.34.1
On 12/2/2022 01:47, Perry Yuan wrote:
> From: Perry Yuan <[email protected]>
>
> Add EPP driver support for AMD SoCs which support a dedicated MSR for
> CPPC. EPP is used by the DPM controller to configure the frequency that
> a core operates at during short periods of activity.
>
> The SoC EPP targets are configured on a scale from 0 to 255 where 0
> represents maximum performance and 255 represents maximum efficiency.
>
> The amd-pstate driver exports profile string names to userspace that are
> tied to specific EPP values.
>
> The balance_performance string (0x80) provides the best balance for
> efficiency versus power on most systems, but users can choose other
> strings to meet their needs as well.
>
> $ cat /sys/devices/system/cpu/cpufreq/policy0/energy_performance_available_preferences
> default performance balance_performance balance_power power
>
> $ cat /sys/devices/system/cpu/cpufreq/policy0/energy_performance_preference
> balance_performance
>
> To enable the driver,it needs to add `amd_pstate=active` to kernel
> command line and kernel will load the active mode epp driver
>
> Signed-off-by: Perry Yuan <[email protected]>
> ---
> drivers/cpufreq/amd-pstate.c | 643 ++++++++++++++++++++++++++++++++++-
> include/linux/amd-pstate.h | 35 ++
> 2 files changed, 672 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 204e39006dda..5989d4d25d0f 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -37,9 +37,12 @@
> #include <linux/uaccess.h>
> #include <linux/static_call.h>
> #include <linux/amd-pstate.h>
> +#include <linux/cpufreq_common.h>
>
> +#ifdef CONFIG_ACPI
> #include <acpi/processor.h>
> #include <acpi/cppc_acpi.h>
> +#endif
>
> #include <asm/msr.h>
> #include <asm/processor.h>
> @@ -59,9 +62,130 @@
> * we disable it by default to go acpi-cpufreq on these processors and add a
> * module parameter to be able to enable it manually for debugging.
> */
> -static struct cpufreq_driver amd_pstate_driver;
> +static bool cppc_active;
> static int cppc_load __initdata;
>
> +static struct cpufreq_driver *default_pstate_driver;
> +static struct amd_cpudata **all_cpu_data;
> +static struct amd_pstate_params global_params;
> +
> +static DEFINE_MUTEX(amd_pstate_limits_lock);
> +static DEFINE_MUTEX(amd_pstate_driver_lock);
> +
> +static bool cppc_boost __read_mostly;
> +struct kobject *amd_pstate_kobj;
> +
> +#ifdef CONFIG_ACPI_CPPC_LIB
Rather than making this conditional I would think that amd-pstate should
probably depend on or select CONFIG_ACPI_CPPC_LIB, no?
> +static s16 amd_pstate_get_epp(struct amd_cpudata *cpudata, u64 cppc_req_cached)
> +{
> + s16 epp;
> + struct cppc_perf_caps perf_caps;
> + int ret;
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + if (!cppc_req_cached) {
> + epp = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ,
> + &cppc_req_cached);
> + if (epp)
> + return epp;
> + }
> + epp = (cppc_req_cached >> 24) & 0xFF;
> + } else {
> + ret = cppc_get_epp_caps(cpudata->cpu, &perf_caps);
> + if (ret < 0) {
> + pr_debug("Could not retrieve energy perf value (%d)\n", ret);
> + return -EIO;
> + }
> + epp = (s16) perf_caps.energy_perf;
> + }
> +
> + return epp;
> +}
> +#endif
> +
> +static int amd_pstate_get_energy_pref_index(struct amd_cpudata *cpudata)
> +{
> + s16 epp;
> + int index = -EINVAL;
> +
> + epp = amd_pstate_get_epp(cpudata, 0);
> + if (epp < 0)
> + return epp;
> +
> + switch (epp) {
> + case HWP_EPP_PERFORMANCE:
> + index = EPP_INDEX_PERFORMANCE;
> + break;
> + case HWP_EPP_BALANCE_PERFORMANCE:
> + index = EPP_INDEX_BALANCE_PERFORMANCE;
> + break;
> + case HWP_EPP_BALANCE_POWERSAVE:
> + index = EPP_INDEX_BALANCE_POWERSAVE;
> + break;
> + case HWP_EPP_POWERSAVE:
> + index = EPP_INDEX_POWERSAVE;
> + break;
> + default:
> + break;
> + }
> +
> + return index;
> +}
> +
> +#ifdef CONFIG_ACPI_CPPC_LIB
> +static int amd_pstate_set_epp(struct amd_cpudata *cpudata, u32 epp)
> +{
> + int ret;
> + struct cppc_perf_ctrls perf_ctrls;
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + u64 value = READ_ONCE(cpudata->cppc_req_cached);
> +
> + value &= ~GENMASK_ULL(31, 24);
> + value |= (u64)epp << 24;
> + WRITE_ONCE(cpudata->cppc_req_cached, value);
> +
> + ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> + if (!ret)
> + cpudata->epp_cached = epp;
> + } else {
> + perf_ctrls.energy_perf = epp;
> + ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> + if (ret) {
> + pr_debug("failed to set energy perf value (%d)\n", ret);
> + return ret;
> + }
> + cpudata->epp_cached = epp;
> + }
> +
> + return ret;
> +}
> +
> +static int amd_pstate_set_energy_pref_index(struct amd_cpudata *cpudata,
> + int pref_index)
> +{
> + int epp = -EINVAL;
> + int ret;
> +
> + if (!pref_index) {
> + pr_debug("EPP pref_index is invalid\n");
> + return -EINVAL;
> + }
> +
> + if (epp == -EINVAL)
> + epp = epp_values[pref_index];
> +
> + if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> + pr_debug("EPP cannot be set under performance policy\n");
> + return -EBUSY;
> + }
> +
> + ret = amd_pstate_set_epp(cpudata, epp);
> +
> + return ret;
> +}
> +#endif
> +
> static inline int pstate_enable(bool enable)
> {
> return wrmsrl_safe(MSR_AMD_CPPC_ENABLE, enable);
> @@ -70,11 +194,21 @@ static inline int pstate_enable(bool enable)
> static int cppc_enable(bool enable)
> {
> int cpu, ret = 0;
> + struct cppc_perf_ctrls perf_ctrls;
>
> for_each_present_cpu(cpu) {
> ret = cppc_set_enable(cpu, enable);
> if (ret)
> return ret;
> +
> + /* Enable autonomous mode for EPP */
> + if (!cppc_active) {
> + /* Set desired perf as zero to allow EPP firmware control */
> + perf_ctrls.desired_perf = 0;
> + ret = cppc_set_perf(cpu, &perf_ctrls);
> + if (ret)
> + return ret;
> + }
> }
>
> return ret;
> @@ -417,7 +551,7 @@ static void amd_pstate_boost_init(struct amd_cpudata *cpudata)
> return;
>
> cpudata->boost_supported = true;
> - amd_pstate_driver.boost_enabled = true;
> + default_pstate_driver->boost_enabled = true;
> }
>
> static void amd_perf_ctl_reset(unsigned int cpu)
> @@ -591,10 +725,61 @@ static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy *policy,
> return sprintf(&buf[0], "%u\n", perf);
> }
>
> +static ssize_t show_energy_performance_available_preferences(
> + struct cpufreq_policy *policy, char *buf)
> +{
> + int i = 0;
> + int ret = 0;
> +
> + while (energy_perf_strings[i] != NULL)
> + ret += sysfs_emit(buf, "%s", energy_perf_strings[i++]);
> +
> + ret += sysfs_emit(buf, "\n");
> +
> + return ret;
> +}
> +
> +static ssize_t store_energy_performance_preference(
> + struct cpufreq_policy *policy, const char *buf, size_t count)
> +{
> + struct amd_cpudata *cpudata = policy->driver_data;
> + char str_preference[21];
> + ssize_t ret;
> +
> + ret = sscanf(buf, "%20s", str_preference);
> + if (ret != 1)
> + return -EINVAL;
> +
> + ret = match_string(energy_perf_strings, -1, str_preference);
> + if (ret < 0)
> + return -EINVAL;
> +
> + mutex_lock(&amd_pstate_limits_lock);
> + ret = amd_pstate_set_energy_pref_index(cpudata, ret);
> + mutex_unlock(&amd_pstate_limits_lock);
> +
> + return ret ?: count;
> +}
> +
> +static ssize_t show_energy_performance_preference(
> + struct cpufreq_policy *policy, char *buf)
> +{
> + struct amd_cpudata *cpudata = policy->driver_data;
> + int preference;
> +
> + preference = amd_pstate_get_energy_pref_index(cpudata);
> + if (preference < 0)
> + return preference;
> +
> + return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]);
You've got an extra space after "return".
> +}
> +
> cpufreq_freq_attr_ro(amd_pstate_max_freq);
> cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
>
> cpufreq_freq_attr_ro(amd_pstate_highest_perf);
> +cpufreq_freq_attr_rw(energy_performance_preference);
> +cpufreq_freq_attr_ro(energy_performance_available_preferences);
>
> static struct freq_attr *amd_pstate_attr[] = {
> &amd_pstate_max_freq,
> @@ -603,6 +788,429 @@ static struct freq_attr *amd_pstate_attr[] = {
> NULL,
> };
>
> +static struct freq_attr *amd_pstate_epp_attr[] = {
> + &amd_pstate_max_freq,
> + &amd_pstate_lowest_nonlinear_freq,
> + &amd_pstate_highest_perf,
> + &energy_performance_preference,
> + &energy_performance_available_preferences,
> + NULL,
> +};
> +
> +static inline void update_boost_state(void)
> +{
> + u64 misc_en;
> + struct amd_cpudata *cpudata;
> +
> + cpudata = all_cpu_data[0];
> + rdmsrl(MSR_K7_HWCR, misc_en);
> + global_params.cppc_boost_disabled = misc_en & BIT_ULL(25);
> +}
> +
> +static bool amd_pstate_acpi_pm_profile_server(void)
> +{
> + if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
> + acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
> + return true;
> +
> + return false;
> +}
Right now this is only used to control boost, but I wonder if this
should instad also control the default EPP policy as all?
> +
> +static int amd_pstate_init_cpu(unsigned int cpunum)
> +{
> + struct amd_cpudata *cpudata;
> +
> + cpudata = all_cpu_data[cpunum];
> + if (!cpudata) {
> + cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL);
> + if (!cpudata)
> + return -ENOMEM;
> + WRITE_ONCE(all_cpu_data[cpunum], cpudata);
> +
> + cpudata->cpu = cpunum;
> +
> + if (cppc_active) {
> + if (amd_pstate_acpi_pm_profile_server())
> + cppc_boost = true;
> + }
> +
> + }
> + cpudata->epp_powersave = -EINVAL;
> + cpudata->epp_policy = 0; > + pr_debug("controlling: cpu %d\n", cpunum);
> + return 0;
> +}
> +
> +static int __amd_pstate_cpu_init(struct cpufreq_policy *policy)
> +{
> + int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
> + struct amd_cpudata *cpudata;
> + struct device *dev;
> + int rc;
> + u64 value;
> +
> + rc = amd_pstate_init_cpu(policy->cpu);
> + if (rc)
> + return rc;
> +
> + cpudata = all_cpu_data[policy->cpu];
> +
> + dev = get_cpu_device(policy->cpu);
> + if (!dev)
> + goto free_cpudata1;
> +
> + rc = amd_pstate_init_perf(cpudata);
> + if (rc)
> + goto free_cpudata1;
> +
> + min_freq = amd_get_min_freq(cpudata);
> + max_freq = amd_get_max_freq(cpudata);
> + nominal_freq = amd_get_nominal_freq(cpudata);
> + lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
> + if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
> + dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
> + min_freq, max_freq);
> + ret = -EINVAL;
> + goto free_cpudata1;
> + }
> +
> + policy->min = min_freq;
> + policy->max = max_freq;
> +
> + policy->cpuinfo.min_freq = min_freq;
> + policy->cpuinfo.max_freq = max_freq;
> + /* It will be updated by governor */
> + policy->cur = policy->cpuinfo.min_freq;
> +
> + /* Initial processor data capability frequencies */
> + cpudata->max_freq = max_freq;
> + cpudata->min_freq = min_freq;
> + cpudata->nominal_freq = nominal_freq;
> + cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
> +
> + policy->driver_data = cpudata;
> +
> + update_boost_state();
> + cpudata->epp_cached = amd_pstate_get_epp(cpudata, value);
> +
> + policy->min = policy->cpuinfo.min_freq;
> + policy->max = policy->cpuinfo.max_freq;
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC))
> + policy->fast_switch_possible = true;
> +
> + if (boot_cpu_has(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 = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1, &value);
> + if (ret)
> + return ret;
> + WRITE_ONCE(cpudata->cppc_cap1_cached, value);
> + }
> + amd_pstate_boost_init(cpudata);
> +
> + return 0;
> +
> +free_cpudata1:
> + kfree(cpudata);
> + return ret;
> +}
> +
> +static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
> +{
> + int ret;
> +
> + ret = __amd_pstate_cpu_init(policy);
> + if (ret)
> + return ret;
> + /*
> + * Set the policy to powersave to provide a valid fallback value in case
> + * the default cpufreq governor is neither powersave nor performance.
> + */
> + policy->policy = CPUFREQ_POLICY_POWERSAVE;
> +
> + return 0;
> +}
> +
> +static int amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy)
> +{
> + pr_debug("CPU %d exiting\n", policy->cpu);
> + policy->fast_switch_possible = false;
> + return 0;
> +}
> +
> +static void amd_pstate_update_max_freq(unsigned int cpu)
> +{
> + struct cpufreq_policy *policy = policy = cpufreq_cpu_get(cpu);
> +
> + if (!policy)
> + return;
> +
> + refresh_frequency_limits(policy);
> + cpufreq_cpu_put(policy);
> +}
> +
> +static void amd_pstate_epp_update_limits(unsigned int cpu)
> +{
> + mutex_lock(&amd_pstate_driver_lock);
> + update_boost_state();
> + if (global_params.cppc_boost_disabled) {
> + for_each_possible_cpu(cpu)
> + amd_pstate_update_max_freq(cpu);
> + } else {
> + cpufreq_update_policy(cpu);
> + }
> + mutex_unlock(&amd_pstate_driver_lock);
> +}
> +
> +static int cppc_boost_hold_time_ns = 3 * NSEC_PER_MSEC;
> +
> +static inline void amd_pstate_boost_up(struct amd_cpudata *cpudata)
> +{
> + u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
> + u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
> + u32 max_limit = (hwp_req & 0xff);
> + u32 min_limit = (hwp_req & 0xff00) >> 8;
> + u32 boost_level1;
> +
> + /* If max and min are equal or already at max, nothing to boost */
> + if (max_limit == min_limit)
> + return;
> +
> + /* Set boost max and min to initial value */
> + if (!cpudata->cppc_boost_min)
> + cpudata->cppc_boost_min = min_limit;
> +
> + boost_level1 = ((AMD_CPPC_NOMINAL_PERF(hwp_cap) + min_limit) >> 1);
> +
> + if (cpudata->cppc_boost_min < boost_level1)
> + cpudata->cppc_boost_min = boost_level1;
> + else if (cpudata->cppc_boost_min < AMD_CPPC_NOMINAL_PERF(hwp_cap))
> + cpudata->cppc_boost_min = AMD_CPPC_NOMINAL_PERF(hwp_cap);
> + else if (cpudata->cppc_boost_min == AMD_CPPC_NOMINAL_PERF(hwp_cap))
> + cpudata->cppc_boost_min = max_limit;
> + else
> + return;
> +
> + hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
> + hwp_req |= AMD_CPPC_MIN_PERF(cpudata->cppc_boost_min);
> + wrmsrl(MSR_AMD_CPPC_REQ, hwp_req);
> + cpudata->last_update = cpudata->sample.time;
> +}
> +
> +static inline void amd_pstate_boost_down(struct amd_cpudata *cpudata)
> +{
> + bool expired;
> +
> + if (cpudata->cppc_boost_min) {
> + expired = time_after64(cpudata->sample.time, cpudata->last_update +
> + cppc_boost_hold_time_ns);
> +
> + if (expired) {
> + wrmsrl(MSR_AMD_CPPC_REQ, cpudata->cppc_req_cached);
> + cpudata->cppc_boost_min = 0;
> + }
> + }
> +
> + cpudata->last_update = cpudata->sample.time;
> +}
> +
> +static inline void amd_pstate_boost_update_util(struct amd_cpudata *cpudata,
> + u64 time)
> +{
> + cpudata->sample.time = time;
> + if (smp_processor_id() != cpudata->cpu)
> + return;
> +
> + if (cpudata->sched_flags & SCHED_CPUFREQ_IOWAIT) {
> + bool do_io = false;
> +
> + cpudata->sched_flags = 0;
> + /*
> + * Set iowait_boost flag and update time. Since IO WAIT flag
> + * is set all the time, we can't just conclude that there is
> + * some IO bound activity is scheduled on this CPU with just
> + * one occurrence. If we receive at least two in two
> + * consecutive ticks, then we treat as boost candidate.
> + * This is leveraged from Intel Pstate driver.
> + */
> + if (time_before64(time, cpudata->last_io_update + 2 * TICK_NSEC))
> + do_io = true;
> +
> + cpudata->last_io_update = time;
> +
> + if (do_io)
> + amd_pstate_boost_up(cpudata);
> +
> + } else {
> + amd_pstate_boost_down(cpudata);
> + }
> +}
> +
> +static inline void amd_pstate_cppc_update_hook(struct update_util_data *data,
> + u64 time, unsigned int flags)
> +{
> + struct amd_cpudata *cpudata = container_of(data,
> + struct amd_cpudata, update_util);
> +
> + cpudata->sched_flags |= flags;
> +
> + if (smp_processor_id() == cpudata->cpu)
> + amd_pstate_boost_update_util(cpudata, time);
> +}
> +
> +static void amd_pstate_clear_update_util_hook(unsigned int cpu)
> +{
> + struct amd_cpudata *cpudata = all_cpu_data[cpu];
> +
> + if (!cpudata->update_util_set)
> + return;
> +
> + cpufreq_remove_update_util_hook(cpu);
> + cpudata->update_util_set = false;
> + synchronize_rcu();
> +}
> +
> +static void amd_pstate_set_update_util_hook(unsigned int cpu_num)
> +{
> + struct amd_cpudata *cpudata = all_cpu_data[cpu_num];
> +
> + if (!cppc_boost) {
> + if (cpudata->update_util_set)
> + amd_pstate_clear_update_util_hook(cpudata->cpu);
> + return;
> + }
> +
> + if (cpudata->update_util_set)
> + return;
> +
> + cpudata->sample.time = 0;
> + cpufreq_add_update_util_hook(cpu_num, &cpudata->update_util,
> + amd_pstate_cppc_update_hook);
> + cpudata->update_util_set = true;
> +}
> +
> +static void amd_pstate_epp_init(unsigned int cpu)
> +{
> + struct amd_cpudata *cpudata = all_cpu_data[cpu];
> + u32 max_perf, min_perf;
> + u64 value;
> + s16 epp;
> + int ret;
> +
> + max_perf = READ_ONCE(cpudata->highest_perf);
> + min_perf = READ_ONCE(cpudata->lowest_perf);
> +
> + value = READ_ONCE(cpudata->cppc_req_cached);
> +
> + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
> + min_perf = max_perf;
> +
> + /* Initial min/max values for CPPC Performance Controls Register */
> + value &= ~AMD_CPPC_MIN_PERF(~0L);
> + value |= AMD_CPPC_MIN_PERF(min_perf);
> +
> + value &= ~AMD_CPPC_MAX_PERF(~0L);
> + value |= AMD_CPPC_MAX_PERF(max_perf);
> +
> + /* CPPC EPP feature require to set zero to the desire perf bit */
> + value &= ~AMD_CPPC_DES_PERF(~0L);
> + value |= AMD_CPPC_DES_PERF(0);
> +
> + if (cpudata->epp_policy == cpudata->policy)
> + goto skip_epp;
> +
> + cpudata->epp_policy = cpudata->policy;
> +
> + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> + epp = amd_pstate_get_epp(cpudata, value);
> + cpudata->epp_powersave = epp;
> + if (epp < 0)
> + goto skip_epp;
> + /* force the epp value to be zero for performance policy */
> + epp = 0;
> + } else {
> + if (cpudata->epp_powersave < 0)
> + goto skip_epp;
> + /* Get BIOS pre-defined epp value */
> + epp = amd_pstate_get_epp(cpudata, value);
> + if (epp)
> + goto skip_epp;
> + epp = cpudata->epp_powersave;
> + }
> + /* Set initial EPP value */
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + value &= ~GENMASK_ULL(31, 24);
> + value |= (u64)epp << 24;
> + }
> +
> +skip_epp:
> + WRITE_ONCE(cpudata->cppc_req_cached, value);
> + ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> + if (!ret)
> + cpudata->epp_cached = epp;
> +}
> +
> +static void amd_pstate_set_max_limits(struct amd_cpudata *cpudata)
> +{
> + u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
> + u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
> + u32 max_limit = (hwp_cap >> 24) & 0xff;
> +
> + hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
> + hwp_req |= AMD_CPPC_MIN_PERF(max_limit);
> + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, hwp_req);
> +}
> +
> +static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
> +{
> + struct amd_cpudata *cpudata;
> +
> + if (!policy->cpuinfo.max_freq)
> + return -ENODEV;
> +
> + pr_debug("set_policy: cpuinfo.max %u policy->max %u\n",
> + policy->cpuinfo.max_freq, policy->max);
> +
> + cpudata = all_cpu_data[policy->cpu];
> + cpudata->policy = policy->policy;
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + mutex_lock(&amd_pstate_limits_lock);
> +
> + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> + amd_pstate_clear_update_util_hook(policy->cpu);
> + amd_pstate_set_max_limits(cpudata);
> + } else {
> + amd_pstate_set_update_util_hook(policy->cpu);
> + }
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC))
> + amd_pstate_epp_init(policy->cpu);
> +
> + mutex_unlock(&amd_pstate_limits_lock);
> + }
> +
> + return 0;
> +}
> +
> +static void amd_pstate_verify_cpu_policy(struct amd_cpudata *cpudata,
> + struct cpufreq_policy_data *policy)
> +{
> + update_boost_state();
> + cpufreq_verify_within_cpu_limits(policy);
> +}
> +
> +static int amd_pstate_epp_verify_policy(struct cpufreq_policy_data *policy)
> +{
> + amd_pstate_verify_cpu_policy(all_cpu_data[policy->cpu], policy);
> + pr_debug("policy_max =%d, policy_min=%d\n", policy->max, policy->min);
> + return 0;
> +}
> +
> static struct cpufreq_driver amd_pstate_driver = {
> .flags = CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_UPDATE_LIMITS,
> .verify = amd_pstate_verify,
> @@ -616,8 +1224,20 @@ static struct cpufreq_driver amd_pstate_driver = {
> .attr = amd_pstate_attr,
> };
>
> +static struct cpufreq_driver amd_pstate_epp_driver = {
> + .flags = CPUFREQ_CONST_LOOPS,
> + .verify = amd_pstate_epp_verify_policy,
> + .setpolicy = amd_pstate_epp_set_policy,
> + .init = amd_pstate_epp_cpu_init,
> + .exit = amd_pstate_epp_cpu_exit,
> + .update_limits = amd_pstate_epp_update_limits,
> + .name = "amd_pstate_epp",
> + .attr = amd_pstate_epp_attr,
> +};
> +
> static int __init amd_pstate_init(void)
> {
> + static struct amd_cpudata **cpudata;
> int ret;
>
> if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
> @@ -644,7 +1264,8 @@ static int __init amd_pstate_init(void)
> /* capability check */
> if (boot_cpu_has(X86_FEATURE_CPPC)) {
> pr_debug("AMD CPPC MSR based functionality is supported\n");
> - amd_pstate_driver.adjust_perf = amd_pstate_adjust_perf;
> + if (!cppc_active)
> + default_pstate_driver->adjust_perf = amd_pstate_adjust_perf;
> } else {
> pr_debug("AMD CPPC shared memory based functionality is supported\n");
> static_call_update(amd_pstate_enable, cppc_enable);
> @@ -652,6 +1273,10 @@ static int __init amd_pstate_init(void)
> static_call_update(amd_pstate_update_perf, cppc_update_perf);
> }
>
> + cpudata = vzalloc(array_size(sizeof(void *), num_possible_cpus()));
> + if (!cpudata)
> + return -ENOMEM;
> + WRITE_ONCE(all_cpu_data, cpudata);
> /* enable amd pstate feature */
> ret = amd_pstate_enable(true);
> if (ret) {
> @@ -659,9 +1284,9 @@ static int __init amd_pstate_init(void)
> return ret;
> }
>
> - ret = cpufreq_register_driver(&amd_pstate_driver);
> + ret = cpufreq_register_driver(default_pstate_driver);
> if (ret)
> - pr_err("failed to register amd_pstate_driver with return %d\n",
> + pr_err("failed to register amd pstate driver with return %d\n",
> ret);
>
> return ret;
> @@ -676,8 +1301,14 @@ static int __init amd_pstate_param(char *str)
> if (!strcmp(str, "disable")) {
> cppc_load = 0;
> pr_info("driver is explicitly disabled\n");
> - } else if (!strcmp(str, "passive"))
> + } else if (!strcmp(str, "passive")) {
> cppc_load = 1;
> + default_pstate_driver = &amd_pstate_driver;
> + } else if (!strcmp(str, "active")) {
> + cppc_active = 1;
> + cppc_load = 1;
> + default_pstate_driver = &amd_pstate_epp_driver;
> + }
>
> return 0;
> }
> diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
> index 1c4b8659f171..888af62040f1 100644
> --- a/include/linux/amd-pstate.h
> +++ b/include/linux/amd-pstate.h
> @@ -25,6 +25,7 @@ struct amd_aperf_mperf {
> u64 aperf;
> u64 mperf;
> u64 tsc;
> + u64 time;
> };
>
> /**
> @@ -47,6 +48,18 @@ struct amd_aperf_mperf {
> * @prev: Last Aperf/Mperf/tsc count value read from register
> * @freq: current cpu frequency value
> * @boost_supported: check whether the Processor or SBIOS supports boost mode
> + * @epp_powersave: Last saved CPPC energy performance preference
> + when policy switched to performance
> + * @epp_policy: Last saved policy used to set energy-performance preference
> + * @epp_cached: Cached CPPC energy-performance preference value
> + * @policy: Cpufreq policy value
> + * @sched_flags: Store scheduler flags for possible cross CPU update
> + * @update_util_set: CPUFreq utility callback is set
> + * @last_update: Time stamp of the last performance state update
> + * @cppc_boost_min: Last CPPC boosted min performance state
> + * @cppc_cap1_cached: Cached value of the last CPPC Capabilities MSR
> + * @update_util: Cpufreq utility callback information
> + * @sample: the stored performance sample
> *
> * The amd_cpudata is key private data for each CPU thread in AMD P-State, and
> * represents all the attributes and goals that AMD P-State requests at runtime.
> @@ -72,6 +85,28 @@ struct amd_cpudata {
>
> u64 freq;
> bool boost_supported;
> +
> + /* EPP feature related attributes*/
> + s16 epp_powersave;
> + s16 epp_policy;
> + s16 epp_cached;
> + u32 policy;
> + u32 sched_flags;
> + bool update_util_set;
> + u64 last_update;
> + u64 last_io_update;
> + u32 cppc_boost_min;
> + u64 cppc_cap1_cached;
> + struct update_util_data update_util;
> + struct amd_aperf_mperf sample;
> +};
> +
> +/**
> + * struct amd_pstate_params - global parameters for the performance control
> + * @ cppc_boost_disabled wheher the core performance boost disabled
> + */
> +struct amd_pstate_params {
> + bool cppc_boost_disabled;
> };
>
> #endif /* _LINUX_AMD_PSTATE_H */
Hi Perry,
I love your patch! Yet something to improve:
[auto build test ERROR on rafael-pm/linux-next]
[also build test ERROR on linus/master v6.1-rc7 next-20221202]
[cannot apply to tip/x86/core]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Perry-Yuan/Implement-AMD-Pstate-EPP-Driver/20221202-155515
base: https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
patch link: https://lore.kernel.org/r/20221202074719.623673-5-perry.yuan%40amd.com
patch subject: [PATCH v6 04/11] cpufreq: amd_pstate: implement Pstate EPP support for the AMD processors
config: i386-allyesconfig
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
reproduce (this is a W=1 build):
# https://github.com/intel-lab-lkp/linux/commit/6f2da26e9fe72400ed922b14ea494beb5e38dc59
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Perry-Yuan/Implement-AMD-Pstate-EPP-Driver/20221202-155515
git checkout 6f2da26e9fe72400ed922b14ea494beb5e38dc59
# save the config file
mkdir build_dir && cp config build_dir/.config
make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
All errors (new ones prefixed by >>):
drivers/cpufreq/amd-pstate.c: In function 'amd_pstate_get_energy_pref_index':
>> drivers/cpufreq/amd-pstate.c:111:15: error: implicit declaration of function 'amd_pstate_get_epp' [-Werror=implicit-function-declaration]
111 | epp = amd_pstate_get_epp(cpudata, 0);
| ^~~~~~~~~~~~~~~~~~
drivers/cpufreq/amd-pstate.c: In function 'store_energy_performance_preference':
>> drivers/cpufreq/amd-pstate.c:758:15: error: implicit declaration of function 'amd_pstate_set_energy_pref_index'; did you mean 'amd_pstate_get_energy_pref_index'? [-Werror=implicit-function-declaration]
758 | ret = amd_pstate_set_energy_pref_index(cpudata, ret);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| amd_pstate_get_energy_pref_index
drivers/cpufreq/amd-pstate.c: In function 'update_boost_state':
drivers/cpufreq/amd-pstate.c:803:29: warning: variable 'cpudata' set but not used [-Wunused-but-set-variable]
803 | struct amd_cpudata *cpudata;
| ^~~~~~~
In file included from drivers/cpufreq/amd-pstate.c:40:
At top level:
include/linux/cpufreq_common.h:48:21: warning: 'epp_values' defined but not used [-Wunused-variable]
48 | static unsigned int epp_values[] = {
| ^~~~~~~~~~
cc1: some warnings being treated as errors
vim +/amd_pstate_get_epp +111 drivers/cpufreq/amd-pstate.c
105
106 static int amd_pstate_get_energy_pref_index(struct amd_cpudata *cpudata)
107 {
108 s16 epp;
109 int index = -EINVAL;
110
> 111 epp = amd_pstate_get_epp(cpudata, 0);
112 if (epp < 0)
113 return epp;
114
115 switch (epp) {
116 case HWP_EPP_PERFORMANCE:
117 index = EPP_INDEX_PERFORMANCE;
118 break;
119 case HWP_EPP_BALANCE_PERFORMANCE:
120 index = EPP_INDEX_BALANCE_PERFORMANCE;
121 break;
122 case HWP_EPP_BALANCE_POWERSAVE:
123 index = EPP_INDEX_BALANCE_POWERSAVE;
124 break;
125 case HWP_EPP_POWERSAVE:
126 index = EPP_INDEX_POWERSAVE;
127 break;
128 default:
129 break;
130 }
131
132 return index;
133 }
134
--
0-DAY CI Kernel Test Service
https://01.org/lkp
On Fri, Dec 02, 2022 at 03:47:12PM +0800, Yuan, Perry wrote:
> From: Perry Yuan <[email protected]>
>
> cpufreq: amd_pstate: implement Pstate EPP support for the AMD processors
I suggest that we align the format like "cpufreq: amd-pstate:" as the
prefix of the subject like previous patches. Because it's there anywhere
even in the documentation file. I think it's not worth to change such as
minor update like amd-pstate to amd_pstate for all the files and comments.
So let's align the previous way.
> Add EPP driver support for AMD SoCs which support a dedicated MSR for
> CPPC. EPP is used by the DPM controller to configure the frequency that
> a core operates at during short periods of activity.
>
> The SoC EPP targets are configured on a scale from 0 to 255 where 0
> represents maximum performance and 255 represents maximum efficiency.
>
> The amd-pstate driver exports profile string names to userspace that are
> tied to specific EPP values.
>
> The balance_performance string (0x80) provides the best balance for
> efficiency versus power on most systems, but users can choose other
> strings to meet their needs as well.
>
> $ cat /sys/devices/system/cpu/cpufreq/policy0/energy_performance_available_preferences
> default performance balance_performance balance_power power
>
> $ cat /sys/devices/system/cpu/cpufreq/policy0/energy_performance_preference
> balance_performance
>
> To enable the driver,it needs to add `amd_pstate=active` to kernel
> command line and kernel will load the active mode epp driver
>
> Signed-off-by: Perry Yuan <[email protected]>
> ---
> drivers/cpufreq/amd-pstate.c | 643 ++++++++++++++++++++++++++++++++++-
> include/linux/amd-pstate.h | 35 ++
> 2 files changed, 672 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 204e39006dda..5989d4d25d0f 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -37,9 +37,12 @@
> #include <linux/uaccess.h>
> #include <linux/static_call.h>
> #include <linux/amd-pstate.h>
> +#include <linux/cpufreq_common.h>
>
> +#ifdef CONFIG_ACPI
> #include <acpi/processor.h>
> #include <acpi/cppc_acpi.h>
> +#endif
The amd-pstate module depends on ACPI in the kconfig, so we won't need add
CONFIG_ACPI here.
>
> #include <asm/msr.h>
> #include <asm/processor.h>
> @@ -59,9 +62,130 @@
> * we disable it by default to go acpi-cpufreq on these processors and add a
> * module parameter to be able to enable it manually for debugging.
> */
> -static struct cpufreq_driver amd_pstate_driver;
> +static bool cppc_active;
> static int cppc_load __initdata;
>
> +static struct cpufreq_driver *default_pstate_driver;
> +static struct amd_cpudata **all_cpu_data;
> +static struct amd_pstate_params global_params;
> +
> +static DEFINE_MUTEX(amd_pstate_limits_lock);
> +static DEFINE_MUTEX(amd_pstate_driver_lock);
> +
> +static bool cppc_boost __read_mostly;
> +struct kobject *amd_pstate_kobj;
Where is it using amd_pstate_kobj?
> +
> +#ifdef CONFIG_ACPI_CPPC_LIB
> +static s16 amd_pstate_get_epp(struct amd_cpudata *cpudata, u64 cppc_req_cached)
> +{
> + s16 epp;
> + struct cppc_perf_caps perf_caps;
> + int ret;
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + if (!cppc_req_cached) {
> + epp = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ,
> + &cppc_req_cached);
> + if (epp)
> + return epp;
> + }
> + epp = (cppc_req_cached >> 24) & 0xFF;
> + } else {
> + ret = cppc_get_epp_caps(cpudata->cpu, &perf_caps);
> + if (ret < 0) {
> + pr_debug("Could not retrieve energy perf value (%d)\n", ret);
> + return -EIO;
> + }
> + epp = (s16) perf_caps.energy_perf;
> + }
> +
> + return epp;
> +}
> +#endif
> +
> +static int amd_pstate_get_energy_pref_index(struct amd_cpudata *cpudata)
> +{
> + s16 epp;
> + int index = -EINVAL;
> +
> + epp = amd_pstate_get_epp(cpudata, 0);
> + if (epp < 0)
> + return epp;
> +
> + switch (epp) {
> + case HWP_EPP_PERFORMANCE:
> + index = EPP_INDEX_PERFORMANCE;
> + break;
> + case HWP_EPP_BALANCE_PERFORMANCE:
> + index = EPP_INDEX_BALANCE_PERFORMANCE;
> + break;
> + case HWP_EPP_BALANCE_POWERSAVE:
> + index = EPP_INDEX_BALANCE_POWERSAVE;
> + break;
> + case HWP_EPP_POWERSAVE:
> + index = EPP_INDEX_POWERSAVE;
> + break;
> + default:
> + break;
> + }
> +
> + return index;
> +}
> +
> +#ifdef CONFIG_ACPI_CPPC_LIB
> +static int amd_pstate_set_epp(struct amd_cpudata *cpudata, u32 epp)
> +{
> + int ret;
> + struct cppc_perf_ctrls perf_ctrls;
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + u64 value = READ_ONCE(cpudata->cppc_req_cached);
> +
> + value &= ~GENMASK_ULL(31, 24);
> + value |= (u64)epp << 24;
> + WRITE_ONCE(cpudata->cppc_req_cached, value);
> +
> + ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> + if (!ret)
> + cpudata->epp_cached = epp;
> + } else {
> + perf_ctrls.energy_perf = epp;
> + ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> + if (ret) {
> + pr_debug("failed to set energy perf value (%d)\n", ret);
> + return ret;
> + }
> + cpudata->epp_cached = epp;
> + }
> +
> + return ret;
> +}
> +
> +static int amd_pstate_set_energy_pref_index(struct amd_cpudata *cpudata,
> + int pref_index)
> +{
> + int epp = -EINVAL;
> + int ret;
> +
> + if (!pref_index) {
> + pr_debug("EPP pref_index is invalid\n");
> + return -EINVAL;
> + }
> +
> + if (epp == -EINVAL)
> + epp = epp_values[pref_index];
> +
> + if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> + pr_debug("EPP cannot be set under performance policy\n");
> + return -EBUSY;
> + }
> +
> + ret = amd_pstate_set_epp(cpudata, epp);
> +
> + return ret;
> +}
> +#endif
> +
> static inline int pstate_enable(bool enable)
> {
> return wrmsrl_safe(MSR_AMD_CPPC_ENABLE, enable);
> @@ -70,11 +194,21 @@ static inline int pstate_enable(bool enable)
> static int cppc_enable(bool enable)
> {
> int cpu, ret = 0;
> + struct cppc_perf_ctrls perf_ctrls;
>
> for_each_present_cpu(cpu) {
> ret = cppc_set_enable(cpu, enable);
> if (ret)
> return ret;
> +
> + /* Enable autonomous mode for EPP */
> + if (!cppc_active) {
> + /* Set desired perf as zero to allow EPP firmware control */
> + perf_ctrls.desired_perf = 0;
> + ret = cppc_set_perf(cpu, &perf_ctrls);
> + if (ret)
> + return ret;
> + }
> }
>
> return ret;
> @@ -417,7 +551,7 @@ static void amd_pstate_boost_init(struct amd_cpudata *cpudata)
> return;
>
> cpudata->boost_supported = true;
> - amd_pstate_driver.boost_enabled = true;
> + default_pstate_driver->boost_enabled = true;
> }
>
> static void amd_perf_ctl_reset(unsigned int cpu)
> @@ -591,10 +725,61 @@ static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy *policy,
> return sprintf(&buf[0], "%u\n", perf);
> }
>
> +static ssize_t show_energy_performance_available_preferences(
> + struct cpufreq_policy *policy, char *buf)
> +{
> + int i = 0;
> + int ret = 0;
> +
> + while (energy_perf_strings[i] != NULL)
> + ret += sysfs_emit(buf, "%s", energy_perf_strings[i++]);
> +
> + ret += sysfs_emit(buf, "\n");
> +
> + return ret;
> +}
> +
> +static ssize_t store_energy_performance_preference(
> + struct cpufreq_policy *policy, const char *buf, size_t count)
> +{
> + struct amd_cpudata *cpudata = policy->driver_data;
> + char str_preference[21];
> + ssize_t ret;
> +
> + ret = sscanf(buf, "%20s", str_preference);
> + if (ret != 1)
> + return -EINVAL;
> +
> + ret = match_string(energy_perf_strings, -1, str_preference);
> + if (ret < 0)
> + return -EINVAL;
> +
> + mutex_lock(&amd_pstate_limits_lock);
> + ret = amd_pstate_set_energy_pref_index(cpudata, ret);
> + mutex_unlock(&amd_pstate_limits_lock);
> +
> + return ret ?: count;
> +}
> +
> +static ssize_t show_energy_performance_preference(
> + struct cpufreq_policy *policy, char *buf)
> +{
> + struct amd_cpudata *cpudata = policy->driver_data;
> + int preference;
> +
> + preference = amd_pstate_get_energy_pref_index(cpudata);
> + if (preference < 0)
> + return preference;
> +
> + return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]);
> +}
> +
> cpufreq_freq_attr_ro(amd_pstate_max_freq);
> cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
>
> cpufreq_freq_attr_ro(amd_pstate_highest_perf);
> +cpufreq_freq_attr_rw(energy_performance_preference);
> +cpufreq_freq_attr_ro(energy_performance_available_preferences);
>
> static struct freq_attr *amd_pstate_attr[] = {
> &amd_pstate_max_freq,
> @@ -603,6 +788,429 @@ static struct freq_attr *amd_pstate_attr[] = {
> NULL,
> };
>
> +static struct freq_attr *amd_pstate_epp_attr[] = {
> + &amd_pstate_max_freq,
> + &amd_pstate_lowest_nonlinear_freq,
> + &amd_pstate_highest_perf,
> + &energy_performance_preference,
> + &energy_performance_available_preferences,
> + NULL,
> +};
> +
> +static inline void update_boost_state(void)
> +{
> + u64 misc_en;
> + struct amd_cpudata *cpudata;
> +
> + cpudata = all_cpu_data[0];
> + rdmsrl(MSR_K7_HWCR, misc_en);
> + global_params.cppc_boost_disabled = misc_en & BIT_ULL(25);
> +}
> +
> +static bool amd_pstate_acpi_pm_profile_server(void)
> +{
> + if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
> + acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
> + return true;
> +
> + return false;
> +}
> +
> +static int amd_pstate_init_cpu(unsigned int cpunum)
> +{
> + struct amd_cpudata *cpudata;
> +
> + cpudata = all_cpu_data[cpunum];
> + if (!cpudata) {
> + cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL);
> + if (!cpudata)
> + return -ENOMEM;
> + WRITE_ONCE(all_cpu_data[cpunum], cpudata);
> +
> + cpudata->cpu = cpunum;
> +
> + if (cppc_active) {
> + if (amd_pstate_acpi_pm_profile_server())
> + cppc_boost = true;
> + }
> +
> + }
> + cpudata->epp_powersave = -EINVAL;
> + cpudata->epp_policy = 0;
> + pr_debug("controlling: cpu %d\n", cpunum);
> + return 0;
> +}
> +
> +static int __amd_pstate_cpu_init(struct cpufreq_policy *policy)
> +{
> + int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
> + struct amd_cpudata *cpudata;
> + struct device *dev;
> + int rc;
> + u64 value;
> +
> + rc = amd_pstate_init_cpu(policy->cpu);
> + if (rc)
> + return rc;
> +
> + cpudata = all_cpu_data[policy->cpu];
> +
> + dev = get_cpu_device(policy->cpu);
> + if (!dev)
> + goto free_cpudata1;
> +
> + rc = amd_pstate_init_perf(cpudata);
> + if (rc)
> + goto free_cpudata1;
> +
> + min_freq = amd_get_min_freq(cpudata);
> + max_freq = amd_get_max_freq(cpudata);
> + nominal_freq = amd_get_nominal_freq(cpudata);
> + lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
> + if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
> + dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
> + min_freq, max_freq);
> + ret = -EINVAL;
> + goto free_cpudata1;
> + }
> +
> + policy->min = min_freq;
> + policy->max = max_freq;
> +
> + policy->cpuinfo.min_freq = min_freq;
> + policy->cpuinfo.max_freq = max_freq;
> + /* It will be updated by governor */
> + policy->cur = policy->cpuinfo.min_freq;
> +
> + /* Initial processor data capability frequencies */
> + cpudata->max_freq = max_freq;
> + cpudata->min_freq = min_freq;
> + cpudata->nominal_freq = nominal_freq;
> + cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
> +
> + policy->driver_data = cpudata;
> +
> + update_boost_state();
> + cpudata->epp_cached = amd_pstate_get_epp(cpudata, value);
> +
> + policy->min = policy->cpuinfo.min_freq;
> + policy->max = policy->cpuinfo.max_freq;
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC))
> + policy->fast_switch_possible = true;
> +
> + if (boot_cpu_has(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 = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1, &value);
> + if (ret)
> + return ret;
> + WRITE_ONCE(cpudata->cppc_cap1_cached, value);
> + }
> + amd_pstate_boost_init(cpudata);
> +
> + return 0;
> +
> +free_cpudata1:
> + kfree(cpudata);
> + return ret;
> +}
> +
> +static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
> +{
> + int ret;
> +
> + ret = __amd_pstate_cpu_init(policy);
> + if (ret)
> + return ret;
> + /*
> + * Set the policy to powersave to provide a valid fallback value in case
> + * the default cpufreq governor is neither powersave nor performance.
> + */
> + policy->policy = CPUFREQ_POLICY_POWERSAVE;
> +
> + return 0;
> +}
> +
> +static int amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy)
> +{
> + pr_debug("CPU %d exiting\n", policy->cpu);
> + policy->fast_switch_possible = false;
> + return 0;
> +}
> +
> +static void amd_pstate_update_max_freq(unsigned int cpu)
> +{
> + struct cpufreq_policy *policy = policy = cpufreq_cpu_get(cpu);
> +
> + if (!policy)
> + return;
> +
> + refresh_frequency_limits(policy);
> + cpufreq_cpu_put(policy);
> +}
> +
> +static void amd_pstate_epp_update_limits(unsigned int cpu)
> +{
> + mutex_lock(&amd_pstate_driver_lock);
> + update_boost_state();
> + if (global_params.cppc_boost_disabled) {
> + for_each_possible_cpu(cpu)
> + amd_pstate_update_max_freq(cpu);
> + } else {
> + cpufreq_update_policy(cpu);
> + }
> + mutex_unlock(&amd_pstate_driver_lock);
> +}
> +
> +static int cppc_boost_hold_time_ns = 3 * NSEC_PER_MSEC;
> +
> +static inline void amd_pstate_boost_up(struct amd_cpudata *cpudata)
> +{
> + u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
> + u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
> + u32 max_limit = (hwp_req & 0xff);
> + u32 min_limit = (hwp_req & 0xff00) >> 8;
> + u32 boost_level1;
> +
> + /* If max and min are equal or already at max, nothing to boost */
> + if (max_limit == min_limit)
> + return;
> +
> + /* Set boost max and min to initial value */
> + if (!cpudata->cppc_boost_min)
> + cpudata->cppc_boost_min = min_limit;
> +
> + boost_level1 = ((AMD_CPPC_NOMINAL_PERF(hwp_cap) + min_limit) >> 1);
> +
> + if (cpudata->cppc_boost_min < boost_level1)
> + cpudata->cppc_boost_min = boost_level1;
> + else if (cpudata->cppc_boost_min < AMD_CPPC_NOMINAL_PERF(hwp_cap))
> + cpudata->cppc_boost_min = AMD_CPPC_NOMINAL_PERF(hwp_cap);
> + else if (cpudata->cppc_boost_min == AMD_CPPC_NOMINAL_PERF(hwp_cap))
> + cpudata->cppc_boost_min = max_limit;
> + else
> + return;
> +
> + hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
> + hwp_req |= AMD_CPPC_MIN_PERF(cpudata->cppc_boost_min);
> + wrmsrl(MSR_AMD_CPPC_REQ, hwp_req);
> + cpudata->last_update = cpudata->sample.time;
> +}
> +
> +static inline void amd_pstate_boost_down(struct amd_cpudata *cpudata)
> +{
> + bool expired;
> +
> + if (cpudata->cppc_boost_min) {
> + expired = time_after64(cpudata->sample.time, cpudata->last_update +
> + cppc_boost_hold_time_ns);
> +
> + if (expired) {
> + wrmsrl(MSR_AMD_CPPC_REQ, cpudata->cppc_req_cached);
> + cpudata->cppc_boost_min = 0;
> + }
> + }
> +
> + cpudata->last_update = cpudata->sample.time;
> +}
> +
> +static inline void amd_pstate_boost_update_util(struct amd_cpudata *cpudata,
> + u64 time)
> +{
> + cpudata->sample.time = time;
> + if (smp_processor_id() != cpudata->cpu)
> + return;
> +
> + if (cpudata->sched_flags & SCHED_CPUFREQ_IOWAIT) {
> + bool do_io = false;
> +
> + cpudata->sched_flags = 0;
> + /*
> + * Set iowait_boost flag and update time. Since IO WAIT flag
> + * is set all the time, we can't just conclude that there is
> + * some IO bound activity is scheduled on this CPU with just
> + * one occurrence. If we receive at least two in two
> + * consecutive ticks, then we treat as boost candidate.
> + * This is leveraged from Intel Pstate driver.
> + */
> + if (time_before64(time, cpudata->last_io_update + 2 * TICK_NSEC))
> + do_io = true;
> +
> + cpudata->last_io_update = time;
> +
> + if (do_io)
> + amd_pstate_boost_up(cpudata);
> +
> + } else {
> + amd_pstate_boost_down(cpudata);
> + }
> +}
> +
> +static inline void amd_pstate_cppc_update_hook(struct update_util_data *data,
> + u64 time, unsigned int flags)
> +{
> + struct amd_cpudata *cpudata = container_of(data,
> + struct amd_cpudata, update_util);
> +
> + cpudata->sched_flags |= flags;
> +
> + if (smp_processor_id() == cpudata->cpu)
> + amd_pstate_boost_update_util(cpudata, time);
> +}
> +
> +static void amd_pstate_clear_update_util_hook(unsigned int cpu)
> +{
> + struct amd_cpudata *cpudata = all_cpu_data[cpu];
> +
> + if (!cpudata->update_util_set)
> + return;
> +
> + cpufreq_remove_update_util_hook(cpu);
> + cpudata->update_util_set = false;
> + synchronize_rcu();
> +}
> +
> +static void amd_pstate_set_update_util_hook(unsigned int cpu_num)
> +{
> + struct amd_cpudata *cpudata = all_cpu_data[cpu_num];
> +
> + if (!cppc_boost) {
> + if (cpudata->update_util_set)
> + amd_pstate_clear_update_util_hook(cpudata->cpu);
> + return;
> + }
> +
> + if (cpudata->update_util_set)
> + return;
> +
> + cpudata->sample.time = 0;
> + cpufreq_add_update_util_hook(cpu_num, &cpudata->update_util,
> + amd_pstate_cppc_update_hook);
> + cpudata->update_util_set = true;
> +}
> +
> +static void amd_pstate_epp_init(unsigned int cpu)
> +{
> + struct amd_cpudata *cpudata = all_cpu_data[cpu];
> + u32 max_perf, min_perf;
> + u64 value;
> + s16 epp;
> + int ret;
> +
> + max_perf = READ_ONCE(cpudata->highest_perf);
> + min_perf = READ_ONCE(cpudata->lowest_perf);
> +
> + value = READ_ONCE(cpudata->cppc_req_cached);
> +
> + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
> + min_perf = max_perf;
> +
> + /* Initial min/max values for CPPC Performance Controls Register */
> + value &= ~AMD_CPPC_MIN_PERF(~0L);
> + value |= AMD_CPPC_MIN_PERF(min_perf);
> +
> + value &= ~AMD_CPPC_MAX_PERF(~0L);
> + value |= AMD_CPPC_MAX_PERF(max_perf);
> +
> + /* CPPC EPP feature require to set zero to the desire perf bit */
> + value &= ~AMD_CPPC_DES_PERF(~0L);
> + value |= AMD_CPPC_DES_PERF(0);
> +
> + if (cpudata->epp_policy == cpudata->policy)
> + goto skip_epp;
> +
> + cpudata->epp_policy = cpudata->policy;
> +
> + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> + epp = amd_pstate_get_epp(cpudata, value);
> + cpudata->epp_powersave = epp;
> + if (epp < 0)
> + goto skip_epp;
> + /* force the epp value to be zero for performance policy */
> + epp = 0;
> + } else {
> + if (cpudata->epp_powersave < 0)
> + goto skip_epp;
> + /* Get BIOS pre-defined epp value */
> + epp = amd_pstate_get_epp(cpudata, value);
> + if (epp)
> + goto skip_epp;
> + epp = cpudata->epp_powersave;
> + }
> + /* Set initial EPP value */
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> + value &= ~GENMASK_ULL(31, 24);
> + value |= (u64)epp << 24;
> + }
> +
> +skip_epp:
> + WRITE_ONCE(cpudata->cppc_req_cached, value);
> + ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> + if (!ret)
> + cpudata->epp_cached = epp;
> +}
> +
> +static void amd_pstate_set_max_limits(struct amd_cpudata *cpudata)
> +{
> + u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
> + u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
> + u32 max_limit = (hwp_cap >> 24) & 0xff;
> +
> + hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
> + hwp_req |= AMD_CPPC_MIN_PERF(max_limit);
> + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, hwp_req);
> +}
> +
> +static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
> +{
> + struct amd_cpudata *cpudata;
> +
> + if (!policy->cpuinfo.max_freq)
> + return -ENODEV;
> +
> + pr_debug("set_policy: cpuinfo.max %u policy->max %u\n",
> + policy->cpuinfo.max_freq, policy->max);
> +
> + cpudata = all_cpu_data[policy->cpu];
> + cpudata->policy = policy->policy;
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC)) {
X86_FEATURE_CPPC indicated the MSR support, but I believe the share memory
CPU also has the EPP, right?
> + mutex_lock(&amd_pstate_limits_lock);
> +
> + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> + amd_pstate_clear_update_util_hook(policy->cpu);
> + amd_pstate_set_max_limits(cpudata);
> + } else {
> + amd_pstate_set_update_util_hook(policy->cpu);
May I know why amd processors also needs to set and update util hook?
> + }
> +
> + if (boot_cpu_has(X86_FEATURE_CPPC))
I am confused why if (boot_cpu_has(X86_FEATURE_CPPC) is still inside of a
if (boot_cpu_has(X86_FEATURE_CPPC)).
> + amd_pstate_epp_init(policy->cpu);
> +
> + mutex_unlock(&amd_pstate_limits_lock);
> + }
> +
> + return 0;
> +}
> +
> +static void amd_pstate_verify_cpu_policy(struct amd_cpudata *cpudata,
> + struct cpufreq_policy_data *policy)
> +{
> + update_boost_state();
> + cpufreq_verify_within_cpu_limits(policy);
> +}
> +
> +static int amd_pstate_epp_verify_policy(struct cpufreq_policy_data *policy)
> +{
> + amd_pstate_verify_cpu_policy(all_cpu_data[policy->cpu], policy);
> + pr_debug("policy_max =%d, policy_min=%d\n", policy->max, policy->min);
> + return 0;
> +}
> +
> static struct cpufreq_driver amd_pstate_driver = {
> .flags = CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_UPDATE_LIMITS,
> .verify = amd_pstate_verify,
> @@ -616,8 +1224,20 @@ static struct cpufreq_driver amd_pstate_driver = {
> .attr = amd_pstate_attr,
> };
>
> +static struct cpufreq_driver amd_pstate_epp_driver = {
> + .flags = CPUFREQ_CONST_LOOPS,
> + .verify = amd_pstate_epp_verify_policy,
> + .setpolicy = amd_pstate_epp_set_policy,
> + .init = amd_pstate_epp_cpu_init,
> + .exit = amd_pstate_epp_cpu_exit,
> + .update_limits = amd_pstate_epp_update_limits,
> + .name = "amd_pstate_epp",
> + .attr = amd_pstate_epp_attr,
> +};
> +
> static int __init amd_pstate_init(void)
> {
> + static struct amd_cpudata **cpudata;
> int ret;
>
> if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
> @@ -644,7 +1264,8 @@ static int __init amd_pstate_init(void)
> /* capability check */
> if (boot_cpu_has(X86_FEATURE_CPPC)) {
> pr_debug("AMD CPPC MSR based functionality is supported\n");
> - amd_pstate_driver.adjust_perf = amd_pstate_adjust_perf;
> + if (!cppc_active)
> + default_pstate_driver->adjust_perf = amd_pstate_adjust_perf;
> } else {
> pr_debug("AMD CPPC shared memory based functionality is supported\n");
> static_call_update(amd_pstate_enable, cppc_enable);
> @@ -652,6 +1273,10 @@ static int __init amd_pstate_init(void)
> static_call_update(amd_pstate_update_perf, cppc_update_perf);
> }
>
> + cpudata = vzalloc(array_size(sizeof(void *), num_possible_cpus()));
> + if (!cpudata)
> + return -ENOMEM;
> + WRITE_ONCE(all_cpu_data, cpudata);
> /* enable amd pstate feature */
> ret = amd_pstate_enable(true);
> if (ret) {
> @@ -659,9 +1284,9 @@ static int __init amd_pstate_init(void)
> return ret;
> }
>
> - ret = cpufreq_register_driver(&amd_pstate_driver);
> + ret = cpufreq_register_driver(default_pstate_driver);
> if (ret)
> - pr_err("failed to register amd_pstate_driver with return %d\n",
> + pr_err("failed to register amd pstate driver with return %d\n",
> ret);
>
> return ret;
> @@ -676,8 +1301,14 @@ static int __init amd_pstate_param(char *str)
> if (!strcmp(str, "disable")) {
> cppc_load = 0;
> pr_info("driver is explicitly disabled\n");
> - } else if (!strcmp(str, "passive"))
> + } else if (!strcmp(str, "passive")) {
> cppc_load = 1;
> + default_pstate_driver = &amd_pstate_driver;
> + } else if (!strcmp(str, "active")) {
> + cppc_active = 1;
> + cppc_load = 1;
> + default_pstate_driver = &amd_pstate_epp_driver;
> + }
>
> return 0;
> }
> diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
> index 1c4b8659f171..888af62040f1 100644
> --- a/include/linux/amd-pstate.h
> +++ b/include/linux/amd-pstate.h
> @@ -25,6 +25,7 @@ struct amd_aperf_mperf {
> u64 aperf;
> u64 mperf;
> u64 tsc;
> + u64 time;
> };
>
> /**
> @@ -47,6 +48,18 @@ struct amd_aperf_mperf {
> * @prev: Last Aperf/Mperf/tsc count value read from register
> * @freq: current cpu frequency value
> * @boost_supported: check whether the Processor or SBIOS supports boost mode
> + * @epp_powersave: Last saved CPPC energy performance preference
> + when policy switched to performance
> + * @epp_policy: Last saved policy used to set energy-performance preference
> + * @epp_cached: Cached CPPC energy-performance preference value
> + * @policy: Cpufreq policy value
> + * @sched_flags: Store scheduler flags for possible cross CPU update
> + * @update_util_set: CPUFreq utility callback is set
> + * @last_update: Time stamp of the last performance state update
> + * @cppc_boost_min: Last CPPC boosted min performance state
> + * @cppc_cap1_cached: Cached value of the last CPPC Capabilities MSR
> + * @update_util: Cpufreq utility callback information
> + * @sample: the stored performance sample
> *
> * The amd_cpudata is key private data for each CPU thread in AMD P-State, and
> * represents all the attributes and goals that AMD P-State requests at runtime.
> @@ -72,6 +85,28 @@ struct amd_cpudata {
>
> u64 freq;
> bool boost_supported;
> +
> + /* EPP feature related attributes*/
> + s16 epp_powersave;
> + s16 epp_policy;
> + s16 epp_cached;
> + u32 policy;
> + u32 sched_flags;
> + bool update_util_set;
> + u64 last_update;
> + u64 last_io_update;
> + u32 cppc_boost_min;
> + u64 cppc_cap1_cached;
> + struct update_util_data update_util;
> + struct amd_aperf_mperf sample;
> +};
> +
> +/**
> + * struct amd_pstate_params - global parameters for the performance control
> + * @ cppc_boost_disabled wheher the core performance boost disabled
> + */
> +struct amd_pstate_params {
> + bool cppc_boost_disabled;
> };
>
> #endif /* _LINUX_AMD_PSTATE_H */
> --
> 2.34.1
>
[AMD Official Use Only - General]
Hi Mario.
> -----Original Message-----
> From: Limonciello, Mario <[email protected]>
> Sent: Saturday, December 3, 2022 1:36 AM
> To: Yuan, Perry <[email protected]>; [email protected]; Huang,
> Ray <[email protected]>; [email protected]
> Cc: Sharma, Deepak <[email protected]>; Fontenot, Nathan
> <[email protected]>; Deucher, Alexander
> <[email protected]>; Huang, Shimmer
> <[email protected]>; Du, Xiaojian <[email protected]>; Meng,
> Li (Jassmine) <[email protected]>; Karny, Wyes <[email protected]>;
> [email protected]; [email protected]
> Subject: Re: [PATCH v6 04/11] cpufreq: amd_pstate: implement Pstate EPP
> support for the AMD processors
>
> On 12/2/2022 01:47, Perry Yuan wrote:
> > From: Perry Yuan <[email protected]>
> >
> > Add EPP driver support for AMD SoCs which support a dedicated MSR for
> > CPPC. EPP is used by the DPM controller to configure the frequency
> > that a core operates at during short periods of activity.
> >
> > The SoC EPP targets are configured on a scale from 0 to 255 where 0
> > represents maximum performance and 255 represents maximum
> efficiency.
> >
> > The amd-pstate driver exports profile string names to userspace that
> > are tied to specific EPP values.
> >
> > The balance_performance string (0x80) provides the best balance for
> > efficiency versus power on most systems, but users can choose other
> > strings to meet their needs as well.
> >
> > $ cat
> >
> /sys/devices/system/cpu/cpufreq/policy0/energy_performance_available_
> p
> > references default performance balance_performance balance_power
> power
> >
> > $ cat
> >
> /sys/devices/system/cpu/cpufreq/policy0/energy_performance_preferenc
> e
> > balance_performance
> >
> > To enable the driver,it needs to add `amd_pstate=active` to kernel
> > command line and kernel will load the active mode epp driver
> >
> > Signed-off-by: Perry Yuan <[email protected]>
> > ---
> > drivers/cpufreq/amd-pstate.c | 643
> ++++++++++++++++++++++++++++++++++-
> > include/linux/amd-pstate.h | 35 ++
> > 2 files changed, 672 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/cpufreq/amd-pstate.c
> > b/drivers/cpufreq/amd-pstate.c index 204e39006dda..5989d4d25d0f
> 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -37,9 +37,12 @@
> > #include <linux/uaccess.h>
> > #include <linux/static_call.h>
> > #include <linux/amd-pstate.h>
> > +#include <linux/cpufreq_common.h>
> >
> > +#ifdef CONFIG_ACPI
> > #include <acpi/processor.h>
> > #include <acpi/cppc_acpi.h>
> > +#endif
> >
> > #include <asm/msr.h>
> > #include <asm/processor.h>
> > @@ -59,9 +62,130 @@
> > * we disable it by default to go acpi-cpufreq on these processors and add
> a
> > * module parameter to be able to enable it manually for debugging.
> > */
> > -static struct cpufreq_driver amd_pstate_driver;
> > +static bool cppc_active;
> > static int cppc_load __initdata;
> >
> > +static struct cpufreq_driver *default_pstate_driver; static struct
> > +amd_cpudata **all_cpu_data; static struct amd_pstate_params
> > +global_params;
> > +
> > +static DEFINE_MUTEX(amd_pstate_limits_lock);
> > +static DEFINE_MUTEX(amd_pstate_driver_lock);
> > +
> > +static bool cppc_boost __read_mostly; struct kobject
> > +*amd_pstate_kobj;
> > +
> > +#ifdef CONFIG_ACPI_CPPC_LIB
> Rather than making this conditional I would think that amd-pstate should
> probably depend on or select CONFIG_ACPI_CPPC_LIB, no?
Yes, the Kconfig select CONFIG_ACPI_CPPC_LIB , I removed the checking in V7.
Thanks for your review.
Perry.
>
> > +static s16 amd_pstate_get_epp(struct amd_cpudata *cpudata, u64
> > +cppc_req_cached) {
> > + s16 epp;
> > + struct cppc_perf_caps perf_caps;
> > + int ret;
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + if (!cppc_req_cached) {
> > + epp = rdmsrl_on_cpu(cpudata->cpu,
> MSR_AMD_CPPC_REQ,
> > + &cppc_req_cached);
> > + if (epp)
> > + return epp;
> > + }
> > + epp = (cppc_req_cached >> 24) & 0xFF;
> > + } else {
> > + ret = cppc_get_epp_caps(cpudata->cpu, &perf_caps);
> > + if (ret < 0) {
> > + pr_debug("Could not retrieve energy perf value
> (%d)\n", ret);
> > + return -EIO;
> > + }
> > + epp = (s16) perf_caps.energy_perf;
> > + }
> > +
> > + return epp;
> > +}
> > +#endif
> > +
> > +static int amd_pstate_get_energy_pref_index(struct amd_cpudata
> > +*cpudata) {
> > + s16 epp;
> > + int index = -EINVAL;
> > +
> > + epp = amd_pstate_get_epp(cpudata, 0);
> > + if (epp < 0)
> > + return epp;
> > +
> > + switch (epp) {
> > + case HWP_EPP_PERFORMANCE:
> > + index = EPP_INDEX_PERFORMANCE;
> > + break;
> > + case HWP_EPP_BALANCE_PERFORMANCE:
> > + index = EPP_INDEX_BALANCE_PERFORMANCE;
> > + break;
> > + case HWP_EPP_BALANCE_POWERSAVE:
> > + index = EPP_INDEX_BALANCE_POWERSAVE;
> > + break;
> > + case HWP_EPP_POWERSAVE:
> > + index = EPP_INDEX_POWERSAVE;
> > + break;
> > + default:
> > + break;
> > + }
> > +
> > + return index;
> > +}
> > +
> > +#ifdef CONFIG_ACPI_CPPC_LIB
> > +static int amd_pstate_set_epp(struct amd_cpudata *cpudata, u32 epp) {
> > + int ret;
> > + struct cppc_perf_ctrls perf_ctrls;
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + u64 value = READ_ONCE(cpudata->cppc_req_cached);
> > +
> > + value &= ~GENMASK_ULL(31, 24);
> > + value |= (u64)epp << 24;
> > + WRITE_ONCE(cpudata->cppc_req_cached, value);
> > +
> > + ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ,
> value);
> > + if (!ret)
> > + cpudata->epp_cached = epp;
> > + } else {
> > + perf_ctrls.energy_perf = epp;
> > + ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> > + if (ret) {
> > + pr_debug("failed to set energy perf value (%d)\n",
> ret);
> > + return ret;
> > + }
> > + cpudata->epp_cached = epp;
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static int amd_pstate_set_energy_pref_index(struct amd_cpudata
> *cpudata,
> > + int pref_index)
> > +{
> > + int epp = -EINVAL;
> > + int ret;
> > +
> > + if (!pref_index) {
> > + pr_debug("EPP pref_index is invalid\n");
> > + return -EINVAL;
> > + }
> > +
> > + if (epp == -EINVAL)
> > + epp = epp_values[pref_index];
> > +
> > + if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
> {
> > + pr_debug("EPP cannot be set under performance policy\n");
> > + return -EBUSY;
> > + }
> > +
> > + ret = amd_pstate_set_epp(cpudata, epp);
> > +
> > + return ret;
> > +}
> > +#endif
> > +
> > static inline int pstate_enable(bool enable)
> > {
> > return wrmsrl_safe(MSR_AMD_CPPC_ENABLE, enable); @@ -70,11
> +194,21
> > @@ static inline int pstate_enable(bool enable)
> > static int cppc_enable(bool enable)
> > {
> > int cpu, ret = 0;
> > + struct cppc_perf_ctrls perf_ctrls;
> >
> > for_each_present_cpu(cpu) {
> > ret = cppc_set_enable(cpu, enable);
> > if (ret)
> > return ret;
> > +
> > + /* Enable autonomous mode for EPP */
> > + if (!cppc_active) {
> > + /* Set desired perf as zero to allow EPP firmware
> control */
> > + perf_ctrls.desired_perf = 0;
> > + ret = cppc_set_perf(cpu, &perf_ctrls);
> > + if (ret)
> > + return ret;
> > + }
> > }
> >
> > return ret;
> > @@ -417,7 +551,7 @@ static void amd_pstate_boost_init(struct
> amd_cpudata *cpudata)
> > return;
> >
> > cpudata->boost_supported = true;
> > - amd_pstate_driver.boost_enabled = true;
> > + default_pstate_driver->boost_enabled = true;
> > }
> >
> > static void amd_perf_ctl_reset(unsigned int cpu) @@ -591,10 +725,61
> > @@ static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy
> *policy,
> > return sprintf(&buf[0], "%u\n", perf);
> > }
> >
> > +static ssize_t show_energy_performance_available_preferences(
> > + struct cpufreq_policy *policy, char *buf) {
> > + int i = 0;
> > + int ret = 0;
> > +
> > + while (energy_perf_strings[i] != NULL)
> > + ret += sysfs_emit(buf, "%s", energy_perf_strings[i++]);
> > +
> > + ret += sysfs_emit(buf, "\n");
> > +
> > + return ret;
> > +}
> > +
> > +static ssize_t store_energy_performance_preference(
> > + struct cpufreq_policy *policy, const char *buf, size_t count) {
> > + struct amd_cpudata *cpudata = policy->driver_data;
> > + char str_preference[21];
> > + ssize_t ret;
> > +
> > + ret = sscanf(buf, "%20s", str_preference);
> > + if (ret != 1)
> > + return -EINVAL;
> > +
> > + ret = match_string(energy_perf_strings, -1, str_preference);
> > + if (ret < 0)
> > + return -EINVAL;
> > +
> > + mutex_lock(&amd_pstate_limits_lock);
> > + ret = amd_pstate_set_energy_pref_index(cpudata, ret);
> > + mutex_unlock(&amd_pstate_limits_lock);
> > +
> > + return ret ?: count;
> > +}
> > +
> > +static ssize_t show_energy_performance_preference(
> > + struct cpufreq_policy *policy, char *buf) {
> > + struct amd_cpudata *cpudata = policy->driver_data;
> > + int preference;
> > +
> > + preference = amd_pstate_get_energy_pref_index(cpudata);
> > + if (preference < 0)
> > + return preference;
> > +
> > + return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]);
>
> You've got an extra space after "return".
Fixed in V7.
>
> > +}
> > +
> > cpufreq_freq_attr_ro(amd_pstate_max_freq);
> > cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
> >
> > cpufreq_freq_attr_ro(amd_pstate_highest_perf);
> > +cpufreq_freq_attr_rw(energy_performance_preference);
> > +cpufreq_freq_attr_ro(energy_performance_available_preferences);
> >
> > static struct freq_attr *amd_pstate_attr[] = {
> > &amd_pstate_max_freq,
> > @@ -603,6 +788,429 @@ static struct freq_attr *amd_pstate_attr[] = {
> > NULL,
> > };
> >
> > +static struct freq_attr *amd_pstate_epp_attr[] = {
> > + &amd_pstate_max_freq,
> > + &amd_pstate_lowest_nonlinear_freq,
> > + &amd_pstate_highest_perf,
> > + &energy_performance_preference,
> > + &energy_performance_available_preferences,
> > + NULL,
> > +};
> > +
> > +static inline void update_boost_state(void) {
> > + u64 misc_en;
> > + struct amd_cpudata *cpudata;
> > +
> > + cpudata = all_cpu_data[0];
> > + rdmsrl(MSR_K7_HWCR, misc_en);
> > + global_params.cppc_boost_disabled = misc_en & BIT_ULL(25); }
> > +
> > +static bool amd_pstate_acpi_pm_profile_server(void)
> > +{
> > + if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
> > + acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
> > + return true;
> > +
> > + return false;
> > +}
>
> Right now this is only used to control boost, but I wonder if this should instad
> also control the default EPP policy as all?
It should be able to control the EPP profile as well if needed.
Currently the default EPP profile is balance_performance for all CPUs.
If we want to set different profile for server CPU, there some are codes can be added here.
>
> > +
> > +static int amd_pstate_init_cpu(unsigned int cpunum) {
> > + struct amd_cpudata *cpudata;
> > +
> > + cpudata = all_cpu_data[cpunum];
> > + if (!cpudata) {
> > + cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL);
> > + if (!cpudata)
> > + return -ENOMEM;
> > + WRITE_ONCE(all_cpu_data[cpunum], cpudata);
> > +
> > + cpudata->cpu = cpunum;
> > +
> > + if (cppc_active) {
> > + if (amd_pstate_acpi_pm_profile_server())
> > + cppc_boost = true;
> > + }
> > +
> > + }
> > + cpudata->epp_powersave = -EINVAL;
> > + cpudata->epp_policy = 0; > + pr_debug("controlling: cpu %d\n",
> cpunum);
> > + return 0;
> > +}
> > +
> > +static int __amd_pstate_cpu_init(struct cpufreq_policy *policy) {
> > + int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
> > + struct amd_cpudata *cpudata;
> > + struct device *dev;
> > + int rc;
> > + u64 value;
> > +
> > + rc = amd_pstate_init_cpu(policy->cpu);
> > + if (rc)
> > + return rc;
> > +
> > + cpudata = all_cpu_data[policy->cpu];
> > +
> > + dev = get_cpu_device(policy->cpu);
> > + if (!dev)
> > + goto free_cpudata1;
> > +
> > + rc = amd_pstate_init_perf(cpudata);
> > + if (rc)
> > + goto free_cpudata1;
> > +
> > + min_freq = amd_get_min_freq(cpudata);
> > + max_freq = amd_get_max_freq(cpudata);
> > + nominal_freq = amd_get_nominal_freq(cpudata);
> > + lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
> > + if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
> > + dev_err(dev, "min_freq(%d) or max_freq(%d) value is
> incorrect\n",
> > + min_freq, max_freq);
> > + ret = -EINVAL;
> > + goto free_cpudata1;
> > + }
> > +
> > + policy->min = min_freq;
> > + policy->max = max_freq;
> > +
> > + policy->cpuinfo.min_freq = min_freq;
> > + policy->cpuinfo.max_freq = max_freq;
> > + /* It will be updated by governor */
> > + policy->cur = policy->cpuinfo.min_freq;
> > +
> > + /* Initial processor data capability frequencies */
> > + cpudata->max_freq = max_freq;
> > + cpudata->min_freq = min_freq;
> > + cpudata->nominal_freq = nominal_freq;
> > + cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
> > +
> > + policy->driver_data = cpudata;
> > +
> > + update_boost_state();
> > + cpudata->epp_cached = amd_pstate_get_epp(cpudata, value);
> > +
> > + policy->min = policy->cpuinfo.min_freq;
> > + policy->max = policy->cpuinfo.max_freq;
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC))
> > + policy->fast_switch_possible = true;
> > +
> > + if (boot_cpu_has(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 = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1,
> &value);
> > + if (ret)
> > + return ret;
> > + WRITE_ONCE(cpudata->cppc_cap1_cached, value);
> > + }
> > + amd_pstate_boost_init(cpudata);
> > +
> > + return 0;
> > +
> > +free_cpudata1:
> > + kfree(cpudata);
> > + return ret;
> > +}
> > +
> > +static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) {
> > + int ret;
> > +
> > + ret = __amd_pstate_cpu_init(policy);
> > + if (ret)
> > + return ret;
> > + /*
> > + * Set the policy to powersave to provide a valid fallback value in case
> > + * the default cpufreq governor is neither powersave nor
> performance.
> > + */
> > + policy->policy = CPUFREQ_POLICY_POWERSAVE;
> > +
> > + return 0;
> > +}
> > +
> > +static int amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy) {
> > + pr_debug("CPU %d exiting\n", policy->cpu);
> > + policy->fast_switch_possible = false;
> > + return 0;
> > +}
> > +
> > +static void amd_pstate_update_max_freq(unsigned int cpu) {
> > + struct cpufreq_policy *policy = policy = cpufreq_cpu_get(cpu);
> > +
> > + if (!policy)
> > + return;
> > +
> > + refresh_frequency_limits(policy);
> > + cpufreq_cpu_put(policy);
> > +}
> > +
> > +static void amd_pstate_epp_update_limits(unsigned int cpu) {
> > + mutex_lock(&amd_pstate_driver_lock);
> > + update_boost_state();
> > + if (global_params.cppc_boost_disabled) {
> > + for_each_possible_cpu(cpu)
> > + amd_pstate_update_max_freq(cpu);
> > + } else {
> > + cpufreq_update_policy(cpu);
> > + }
> > + mutex_unlock(&amd_pstate_driver_lock);
> > +}
> > +
> > +static int cppc_boost_hold_time_ns = 3 * NSEC_PER_MSEC;
> > +
> > +static inline void amd_pstate_boost_up(struct amd_cpudata *cpudata) {
> > + u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
> > + u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
> > + u32 max_limit = (hwp_req & 0xff);
> > + u32 min_limit = (hwp_req & 0xff00) >> 8;
> > + u32 boost_level1;
> > +
> > + /* If max and min are equal or already at max, nothing to boost */
> > + if (max_limit == min_limit)
> > + return;
> > +
> > + /* Set boost max and min to initial value */
> > + if (!cpudata->cppc_boost_min)
> > + cpudata->cppc_boost_min = min_limit;
> > +
> > + boost_level1 = ((AMD_CPPC_NOMINAL_PERF(hwp_cap) +
> min_limit) >> 1);
> > +
> > + if (cpudata->cppc_boost_min < boost_level1)
> > + cpudata->cppc_boost_min = boost_level1;
> > + else if (cpudata->cppc_boost_min <
> AMD_CPPC_NOMINAL_PERF(hwp_cap))
> > + cpudata->cppc_boost_min =
> AMD_CPPC_NOMINAL_PERF(hwp_cap);
> > + else if (cpudata->cppc_boost_min ==
> AMD_CPPC_NOMINAL_PERF(hwp_cap))
> > + cpudata->cppc_boost_min = max_limit;
> > + else
> > + return;
> > +
> > + hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
> > + hwp_req |= AMD_CPPC_MIN_PERF(cpudata->cppc_boost_min);
> > + wrmsrl(MSR_AMD_CPPC_REQ, hwp_req);
> > + cpudata->last_update = cpudata->sample.time; }
> > +
> > +static inline void amd_pstate_boost_down(struct amd_cpudata *cpudata)
> > +{
> > + bool expired;
> > +
> > + if (cpudata->cppc_boost_min) {
> > + expired = time_after64(cpudata->sample.time, cpudata-
> >last_update +
> > + cppc_boost_hold_time_ns);
> > +
> > + if (expired) {
> > + wrmsrl(MSR_AMD_CPPC_REQ, cpudata-
> >cppc_req_cached);
> > + cpudata->cppc_boost_min = 0;
> > + }
> > + }
> > +
> > + cpudata->last_update = cpudata->sample.time; }
> > +
> > +static inline void amd_pstate_boost_update_util(struct amd_cpudata
> *cpudata,
> > + u64 time)
> > +{
> > + cpudata->sample.time = time;
> > + if (smp_processor_id() != cpudata->cpu)
> > + return;
> > +
> > + if (cpudata->sched_flags & SCHED_CPUFREQ_IOWAIT) {
> > + bool do_io = false;
> > +
> > + cpudata->sched_flags = 0;
> > + /*
> > + * Set iowait_boost flag and update time. Since IO WAIT flag
> > + * is set all the time, we can't just conclude that there is
> > + * some IO bound activity is scheduled on this CPU with just
> > + * one occurrence. If we receive at least two in two
> > + * consecutive ticks, then we treat as boost candidate.
> > + * This is leveraged from Intel Pstate driver.
> > + */
> > + if (time_before64(time, cpudata->last_io_update + 2 *
> TICK_NSEC))
> > + do_io = true;
> > +
> > + cpudata->last_io_update = time;
> > +
> > + if (do_io)
> > + amd_pstate_boost_up(cpudata);
> > +
> > + } else {
> > + amd_pstate_boost_down(cpudata);
> > + }
> > +}
> > +
> > +static inline void amd_pstate_cppc_update_hook(struct update_util_data
> *data,
> > + u64 time, unsigned int flags)
> > +{
> > + struct amd_cpudata *cpudata = container_of(data,
> > + struct amd_cpudata, update_util);
> > +
> > + cpudata->sched_flags |= flags;
> > +
> > + if (smp_processor_id() == cpudata->cpu)
> > + amd_pstate_boost_update_util(cpudata, time); }
> > +
> > +static void amd_pstate_clear_update_util_hook(unsigned int cpu) {
> > + struct amd_cpudata *cpudata = all_cpu_data[cpu];
> > +
> > + if (!cpudata->update_util_set)
> > + return;
> > +
> > + cpufreq_remove_update_util_hook(cpu);
> > + cpudata->update_util_set = false;
> > + synchronize_rcu();
> > +}
> > +
> > +static void amd_pstate_set_update_util_hook(unsigned int cpu_num) {
> > + struct amd_cpudata *cpudata = all_cpu_data[cpu_num];
> > +
> > + if (!cppc_boost) {
> > + if (cpudata->update_util_set)
> > + amd_pstate_clear_update_util_hook(cpudata->cpu);
> > + return;
> > + }
> > +
> > + if (cpudata->update_util_set)
> > + return;
> > +
> > + cpudata->sample.time = 0;
> > + cpufreq_add_update_util_hook(cpu_num, &cpudata->update_util,
> > +
> amd_pstate_cppc_update_hook);
> > + cpudata->update_util_set = true;
> > +}
> > +
> > +static void amd_pstate_epp_init(unsigned int cpu) {
> > + struct amd_cpudata *cpudata = all_cpu_data[cpu];
> > + u32 max_perf, min_perf;
> > + u64 value;
> > + s16 epp;
> > + int ret;
> > +
> > + max_perf = READ_ONCE(cpudata->highest_perf);
> > + min_perf = READ_ONCE(cpudata->lowest_perf);
> > +
> > + value = READ_ONCE(cpudata->cppc_req_cached);
> > +
> > + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
> > + min_perf = max_perf;
> > +
> > + /* Initial min/max values for CPPC Performance Controls Register */
> > + value &= ~AMD_CPPC_MIN_PERF(~0L);
> > + value |= AMD_CPPC_MIN_PERF(min_perf);
> > +
> > + value &= ~AMD_CPPC_MAX_PERF(~0L);
> > + value |= AMD_CPPC_MAX_PERF(max_perf);
> > +
> > + /* CPPC EPP feature require to set zero to the desire perf bit */
> > + value &= ~AMD_CPPC_DES_PERF(~0L);
> > + value |= AMD_CPPC_DES_PERF(0);
> > +
> > + if (cpudata->epp_policy == cpudata->policy)
> > + goto skip_epp;
> > +
> > + cpudata->epp_policy = cpudata->policy;
> > +
> > + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> > + epp = amd_pstate_get_epp(cpudata, value);
> > + cpudata->epp_powersave = epp;
> > + if (epp < 0)
> > + goto skip_epp;
> > + /* force the epp value to be zero for performance policy */
> > + epp = 0;
> > + } else {
> > + if (cpudata->epp_powersave < 0)
> > + goto skip_epp;
> > + /* Get BIOS pre-defined epp value */
> > + epp = amd_pstate_get_epp(cpudata, value);
> > + if (epp)
> > + goto skip_epp;
> > + epp = cpudata->epp_powersave;
> > + }
> > + /* Set initial EPP value */
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + value &= ~GENMASK_ULL(31, 24);
> > + value |= (u64)epp << 24;
> > + }
> > +
> > +skip_epp:
> > + WRITE_ONCE(cpudata->cppc_req_cached, value);
> > + ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> > + if (!ret)
> > + cpudata->epp_cached = epp;
> > +}
> > +
> > +static void amd_pstate_set_max_limits(struct amd_cpudata *cpudata) {
> > + u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
> > + u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
> > + u32 max_limit = (hwp_cap >> 24) & 0xff;
> > +
> > + hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
> > + hwp_req |= AMD_CPPC_MIN_PERF(max_limit);
> > + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, hwp_req); }
> > +
> > +static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) {
> > + struct amd_cpudata *cpudata;
> > +
> > + if (!policy->cpuinfo.max_freq)
> > + return -ENODEV;
> > +
> > + pr_debug("set_policy: cpuinfo.max %u policy->max %u\n",
> > + policy->cpuinfo.max_freq, policy->max);
> > +
> > + cpudata = all_cpu_data[policy->cpu];
> > + cpudata->policy = policy->policy;
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + mutex_lock(&amd_pstate_limits_lock);
> > +
> > + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> > + amd_pstate_clear_update_util_hook(policy->cpu);
> > + amd_pstate_set_max_limits(cpudata);
> > + } else {
> > + amd_pstate_set_update_util_hook(policy->cpu);
> > + }
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC))
> > + amd_pstate_epp_init(policy->cpu);
> > +
> > + mutex_unlock(&amd_pstate_limits_lock);
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static void amd_pstate_verify_cpu_policy(struct amd_cpudata *cpudata,
> > + struct cpufreq_policy_data *policy)
> {
> > + update_boost_state();
> > + cpufreq_verify_within_cpu_limits(policy);
> > +}
> > +
> > +static int amd_pstate_epp_verify_policy(struct cpufreq_policy_data
> > +*policy) {
> > + amd_pstate_verify_cpu_policy(all_cpu_data[policy->cpu], policy);
> > + pr_debug("policy_max =%d, policy_min=%d\n", policy->max, policy-
> >min);
> > + return 0;
> > +}
> > +
> > static struct cpufreq_driver amd_pstate_driver = {
> > .flags = CPUFREQ_CONST_LOOPS |
> CPUFREQ_NEED_UPDATE_LIMITS,
> > .verify = amd_pstate_verify,
> > @@ -616,8 +1224,20 @@ static struct cpufreq_driver amd_pstate_driver =
> {
> > .attr = amd_pstate_attr,
> > };
> >
> > +static struct cpufreq_driver amd_pstate_epp_driver = {
> > + .flags = CPUFREQ_CONST_LOOPS,
> > + .verify = amd_pstate_epp_verify_policy,
> > + .setpolicy = amd_pstate_epp_set_policy,
> > + .init = amd_pstate_epp_cpu_init,
> > + .exit = amd_pstate_epp_cpu_exit,
> > + .update_limits = amd_pstate_epp_update_limits,
> > + .name = "amd_pstate_epp",
> > + .attr = amd_pstate_epp_attr,
> > +};
> > +
> > static int __init amd_pstate_init(void)
> > {
> > + static struct amd_cpudata **cpudata;
> > int ret;
> >
> > if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) @@ -644,7
> +1264,8
> > @@ static int __init amd_pstate_init(void)
> > /* capability check */
> > if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > pr_debug("AMD CPPC MSR based functionality is
> supported\n");
> > - amd_pstate_driver.adjust_perf = amd_pstate_adjust_perf;
> > + if (!cppc_active)
> > + default_pstate_driver->adjust_perf =
> amd_pstate_adjust_perf;
> > } else {
> > pr_debug("AMD CPPC shared memory based functionality is
> supported\n");
> > static_call_update(amd_pstate_enable, cppc_enable); @@ -
> 652,6
> > +1273,10 @@ static int __init amd_pstate_init(void)
> > static_call_update(amd_pstate_update_perf,
> cppc_update_perf);
> > }
> >
> > + cpudata = vzalloc(array_size(sizeof(void *), num_possible_cpus()));
> > + if (!cpudata)
> > + return -ENOMEM;
> > + WRITE_ONCE(all_cpu_data, cpudata);
> > /* enable amd pstate feature */
> > ret = amd_pstate_enable(true);
> > if (ret) {
> > @@ -659,9 +1284,9 @@ static int __init amd_pstate_init(void)
> > return ret;
> > }
> >
> > - ret = cpufreq_register_driver(&amd_pstate_driver);
> > + ret = cpufreq_register_driver(default_pstate_driver);
> > if (ret)
> > - pr_err("failed to register amd_pstate_driver with
> return %d\n",
> > + pr_err("failed to register amd pstate driver with
> return %d\n",
> > ret);
> >
> > return ret;
> > @@ -676,8 +1301,14 @@ static int __init amd_pstate_param(char *str)
> > if (!strcmp(str, "disable")) {
> > cppc_load = 0;
> > pr_info("driver is explicitly disabled\n");
> > - } else if (!strcmp(str, "passive"))
> > + } else if (!strcmp(str, "passive")) {
> > cppc_load = 1;
> > + default_pstate_driver = &amd_pstate_driver;
> > + } else if (!strcmp(str, "active")) {
> > + cppc_active = 1;
> > + cppc_load = 1;
> > + default_pstate_driver = &amd_pstate_epp_driver;
> > + }
> >
> > return 0;
> > }
> > diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
> > index 1c4b8659f171..888af62040f1 100644
> > --- a/include/linux/amd-pstate.h
> > +++ b/include/linux/amd-pstate.h
> > @@ -25,6 +25,7 @@ struct amd_aperf_mperf {
> > u64 aperf;
> > u64 mperf;
> > u64 tsc;
> > + u64 time;
> > };
> >
> > /**
> > @@ -47,6 +48,18 @@ struct amd_aperf_mperf {
> > * @prev: Last Aperf/Mperf/tsc count value read from register
> > * @freq: current cpu frequency value
> > * @boost_supported: check whether the Processor or SBIOS supports
> > boost mode
> > + * @epp_powersave: Last saved CPPC energy performance preference
> > + when policy switched to performance
> > + * @epp_policy: Last saved policy used to set energy-performance
> > +preference
> > + * @epp_cached: Cached CPPC energy-performance preference value
> > + * @policy: Cpufreq policy value
> > + * @sched_flags: Store scheduler flags for possible cross CPU update
> > + * @update_util_set: CPUFreq utility callback is set
> > + * @last_update: Time stamp of the last performance state update
> > + * @cppc_boost_min: Last CPPC boosted min performance state
> > + * @cppc_cap1_cached: Cached value of the last CPPC Capabilities MSR
> > + * @update_util: Cpufreq utility callback information
> > + * @sample: the stored performance sample
> > *
> > * The amd_cpudata is key private data for each CPU thread in AMD P-
> State, and
> > * represents all the attributes and goals that AMD P-State requests at
> runtime.
> > @@ -72,6 +85,28 @@ struct amd_cpudata {
> >
> > u64 freq;
> > bool boost_supported;
> > +
> > + /* EPP feature related attributes*/
> > + s16 epp_powersave;
> > + s16 epp_policy;
> > + s16 epp_cached;
> > + u32 policy;
> > + u32 sched_flags;
> > + bool update_util_set;
> > + u64 last_update;
> > + u64 last_io_update;
> > + u32 cppc_boost_min;
> > + u64 cppc_cap1_cached;
> > + struct update_util_data update_util;
> > + struct amd_aperf_mperf sample;
> > +};
> > +
> > +/**
> > + * struct amd_pstate_params - global parameters for the performance
> > +control
> > + * @ cppc_boost_disabled wheher the core performance boost disabled
> > +*/ struct amd_pstate_params {
> > + bool cppc_boost_disabled;
> > };
> >
> > #endif /* _LINUX_AMD_PSTATE_H */
[AMD Official Use Only - General]
Hi Ray,
> -----Original Message-----
> From: Huang, Ray <[email protected]>
> Sent: Monday, December 5, 2022 8:22 PM
> To: Yuan, Perry <[email protected]>
> Cc: [email protected]; Limonciello, Mario
> <[email protected]>; [email protected]; Sharma, Deepak
> <[email protected]>; Fontenot, Nathan
> <[email protected]>; Deucher, Alexander
> <[email protected]>; Huang, Shimmer
> <[email protected]>; Du, Xiaojian <[email protected]>; Meng,
> Li (Jassmine) <[email protected]>; Karny, Wyes <[email protected]>;
> [email protected]; [email protected]
> Subject: Re: [PATCH v6 04/11] cpufreq: amd_pstate: implement Pstate EPP
> support for the AMD processors
>
> On Fri, Dec 02, 2022 at 03:47:12PM +0800, Yuan, Perry wrote:
> > From: Perry Yuan <[email protected]>
> >
>
> > cpufreq: amd_pstate: implement Pstate EPP support for the AMD
> > processors
>
> I suggest that we align the format like "cpufreq: amd-pstate:" as the prefix of
> the subject like previous patches. Because it's there anywhere even in the
> documentation file. I think it's not worth to change such as minor update like
> amd-pstate to amd_pstate for all the files and comments.
> So let's align the previous way.
Agreed , I have revised the title and part of the kernel docs update patches in V7.
Please take a look at the v7 if you have some other concerns.
>
> > Add EPP driver support for AMD SoCs which support a dedicated MSR for
> > CPPC. EPP is used by the DPM controller to configure the frequency
> > that a core operates at during short periods of activity.
> >
> > The SoC EPP targets are configured on a scale from 0 to 255 where 0
> > represents maximum performance and 255 represents maximum
> efficiency.
> >
> > The amd-pstate driver exports profile string names to userspace that
> > are tied to specific EPP values.
> >
> > The balance_performance string (0x80) provides the best balance for
> > efficiency versus power on most systems, but users can choose other
> > strings to meet their needs as well.
> >
> > $ cat
> >
> /sys/devices/system/cpu/cpufreq/policy0/energy_performance_available_
> p
> > references default performance balance_performance balance_power
> power
> >
> > $ cat
> >
> /sys/devices/system/cpu/cpufreq/policy0/energy_performance_preferenc
> e
> > balance_performance
> >
> > To enable the driver,it needs to add `amd_pstate=active` to kernel
> > command line and kernel will load the active mode epp driver
> >
> > Signed-off-by: Perry Yuan <[email protected]>
> > ---
> > drivers/cpufreq/amd-pstate.c | 643
> ++++++++++++++++++++++++++++++++++-
> > include/linux/amd-pstate.h | 35 ++
> > 2 files changed, 672 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/cpufreq/amd-pstate.c
> > b/drivers/cpufreq/amd-pstate.c index 204e39006dda..5989d4d25d0f
> 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -37,9 +37,12 @@
> > #include <linux/uaccess.h>
> > #include <linux/static_call.h>
> > #include <linux/amd-pstate.h>
> > +#include <linux/cpufreq_common.h>
> >
> > +#ifdef CONFIG_ACPI
> > #include <acpi/processor.h>
> > #include <acpi/cppc_acpi.h>
> > +#endif
>
> The amd-pstate module depends on ACPI in the kconfig, so we won't need
> add CONFIG_ACPI here.
Removed in V7.
>
> >
> > #include <asm/msr.h>
> > #include <asm/processor.h>
> > @@ -59,9 +62,130 @@
> > * we disable it by default to go acpi-cpufreq on these processors and add
> a
> > * module parameter to be able to enable it manually for debugging.
> > */
> > -static struct cpufreq_driver amd_pstate_driver;
> > +static bool cppc_active;
> > static int cppc_load __initdata;
> >
> > +static struct cpufreq_driver *default_pstate_driver; static struct
> > +amd_cpudata **all_cpu_data; static struct amd_pstate_params
> > +global_params;
> > +
> > +static DEFINE_MUTEX(amd_pstate_limits_lock);
> > +static DEFINE_MUTEX(amd_pstate_driver_lock);
> > +
> > +static bool cppc_boost __read_mostly; struct kobject
> > +*amd_pstate_kobj;
>
> Where is it using amd_pstate_kobj?
Moved the amd_pstate_kobj definition to the patch where it is actually used in v7.
>
> > +
> > +#ifdef CONFIG_ACPI_CPPC_LIB
> > +static s16 amd_pstate_get_epp(struct amd_cpudata *cpudata, u64
> > +cppc_req_cached) {
> > + s16 epp;
> > + struct cppc_perf_caps perf_caps;
> > + int ret;
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + if (!cppc_req_cached) {
> > + epp = rdmsrl_on_cpu(cpudata->cpu,
> MSR_AMD_CPPC_REQ,
> > + &cppc_req_cached);
> > + if (epp)
> > + return epp;
> > + }
> > + epp = (cppc_req_cached >> 24) & 0xFF;
> > + } else {
> > + ret = cppc_get_epp_caps(cpudata->cpu, &perf_caps);
> > + if (ret < 0) {
> > + pr_debug("Could not retrieve energy perf value
> (%d)\n", ret);
> > + return -EIO;
> > + }
> > + epp = (s16) perf_caps.energy_perf;
> > + }
> > +
> > + return epp;
> > +}
> > +#endif
> > +
> > +static int amd_pstate_get_energy_pref_index(struct amd_cpudata
> > +*cpudata) {
> > + s16 epp;
> > + int index = -EINVAL;
> > +
> > + epp = amd_pstate_get_epp(cpudata, 0);
> > + if (epp < 0)
> > + return epp;
> > +
> > + switch (epp) {
> > + case HWP_EPP_PERFORMANCE:
> > + index = EPP_INDEX_PERFORMANCE;
> > + break;
> > + case HWP_EPP_BALANCE_PERFORMANCE:
> > + index = EPP_INDEX_BALANCE_PERFORMANCE;
> > + break;
> > + case HWP_EPP_BALANCE_POWERSAVE:
> > + index = EPP_INDEX_BALANCE_POWERSAVE;
> > + break;
> > + case HWP_EPP_POWERSAVE:
> > + index = EPP_INDEX_POWERSAVE;
> > + break;
> > + default:
> > + break;
> > + }
> > +
> > + return index;
> > +}
> > +
> > +#ifdef CONFIG_ACPI_CPPC_LIB
> > +static int amd_pstate_set_epp(struct amd_cpudata *cpudata, u32 epp) {
> > + int ret;
> > + struct cppc_perf_ctrls perf_ctrls;
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + u64 value = READ_ONCE(cpudata->cppc_req_cached);
> > +
> > + value &= ~GENMASK_ULL(31, 24);
> > + value |= (u64)epp << 24;
> > + WRITE_ONCE(cpudata->cppc_req_cached, value);
> > +
> > + ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ,
> value);
> > + if (!ret)
> > + cpudata->epp_cached = epp;
> > + } else {
> > + perf_ctrls.energy_perf = epp;
> > + ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> > + if (ret) {
> > + pr_debug("failed to set energy perf value (%d)\n",
> ret);
> > + return ret;
> > + }
> > + cpudata->epp_cached = epp;
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static int amd_pstate_set_energy_pref_index(struct amd_cpudata
> *cpudata,
> > + int pref_index)
> > +{
> > + int epp = -EINVAL;
> > + int ret;
> > +
> > + if (!pref_index) {
> > + pr_debug("EPP pref_index is invalid\n");
> > + return -EINVAL;
> > + }
> > +
> > + if (epp == -EINVAL)
> > + epp = epp_values[pref_index];
> > +
> > + if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
> {
> > + pr_debug("EPP cannot be set under performance policy\n");
> > + return -EBUSY;
> > + }
> > +
> > + ret = amd_pstate_set_epp(cpudata, epp);
> > +
> > + return ret;
> > +}
> > +#endif
> > +
> > static inline int pstate_enable(bool enable) {
> > return wrmsrl_safe(MSR_AMD_CPPC_ENABLE, enable); @@ -70,11
> +194,21
> > @@ static inline int pstate_enable(bool enable) static int
> > cppc_enable(bool enable) {
> > int cpu, ret = 0;
> > + struct cppc_perf_ctrls perf_ctrls;
> >
> > for_each_present_cpu(cpu) {
> > ret = cppc_set_enable(cpu, enable);
> > if (ret)
> > return ret;
> > +
> > + /* Enable autonomous mode for EPP */
> > + if (!cppc_active) {
> > + /* Set desired perf as zero to allow EPP firmware
> control */
> > + perf_ctrls.desired_perf = 0;
> > + ret = cppc_set_perf(cpu, &perf_ctrls);
> > + if (ret)
> > + return ret;
> > + }
> > }
> >
> > return ret;
> > @@ -417,7 +551,7 @@ static void amd_pstate_boost_init(struct
> amd_cpudata *cpudata)
> > return;
> >
> > cpudata->boost_supported = true;
> > - amd_pstate_driver.boost_enabled = true;
> > + default_pstate_driver->boost_enabled = true;
> > }
> >
> > static void amd_perf_ctl_reset(unsigned int cpu) @@ -591,10 +725,61
> > @@ static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy
> *policy,
> > return sprintf(&buf[0], "%u\n", perf); }
> >
> > +static ssize_t show_energy_performance_available_preferences(
> > + struct cpufreq_policy *policy, char *buf) {
> > + int i = 0;
> > + int ret = 0;
> > +
> > + while (energy_perf_strings[i] != NULL)
> > + ret += sysfs_emit(buf, "%s", energy_perf_strings[i++]);
> > +
> > + ret += sysfs_emit(buf, "\n");
> > +
> > + return ret;
> > +}
> > +
> > +static ssize_t store_energy_performance_preference(
> > + struct cpufreq_policy *policy, const char *buf, size_t count) {
> > + struct amd_cpudata *cpudata = policy->driver_data;
> > + char str_preference[21];
> > + ssize_t ret;
> > +
> > + ret = sscanf(buf, "%20s", str_preference);
> > + if (ret != 1)
> > + return -EINVAL;
> > +
> > + ret = match_string(energy_perf_strings, -1, str_preference);
> > + if (ret < 0)
> > + return -EINVAL;
> > +
> > + mutex_lock(&amd_pstate_limits_lock);
> > + ret = amd_pstate_set_energy_pref_index(cpudata, ret);
> > + mutex_unlock(&amd_pstate_limits_lock);
> > +
> > + return ret ?: count;
> > +}
> > +
> > +static ssize_t show_energy_performance_preference(
> > + struct cpufreq_policy *policy, char *buf) {
> > + struct amd_cpudata *cpudata = policy->driver_data;
> > + int preference;
> > +
> > + preference = amd_pstate_get_energy_pref_index(cpudata);
> > + if (preference < 0)
> > + return preference;
> > +
> > + return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]); }
> > +
> > cpufreq_freq_attr_ro(amd_pstate_max_freq);
> > cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
> >
> > cpufreq_freq_attr_ro(amd_pstate_highest_perf);
> > +cpufreq_freq_attr_rw(energy_performance_preference);
> > +cpufreq_freq_attr_ro(energy_performance_available_preferences);
> >
> > static struct freq_attr *amd_pstate_attr[] = {
> > &amd_pstate_max_freq,
> > @@ -603,6 +788,429 @@ static struct freq_attr *amd_pstate_attr[] = {
> > NULL,
> > };
> >
> > +static struct freq_attr *amd_pstate_epp_attr[] = {
> > + &amd_pstate_max_freq,
> > + &amd_pstate_lowest_nonlinear_freq,
> > + &amd_pstate_highest_perf,
> > + &energy_performance_preference,
> > + &energy_performance_available_preferences,
> > + NULL,
> > +};
> > +
> > +static inline void update_boost_state(void) {
> > + u64 misc_en;
> > + struct amd_cpudata *cpudata;
> > +
> > + cpudata = all_cpu_data[0];
> > + rdmsrl(MSR_K7_HWCR, misc_en);
> > + global_params.cppc_boost_disabled = misc_en & BIT_ULL(25); }
> > +
> > +static bool amd_pstate_acpi_pm_profile_server(void)
> > +{
> > + if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
> > + acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
> > + return true;
> > +
> > + return false;
> > +}
> > +
> > +static int amd_pstate_init_cpu(unsigned int cpunum) {
> > + struct amd_cpudata *cpudata;
> > +
> > + cpudata = all_cpu_data[cpunum];
> > + if (!cpudata) {
> > + cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL);
> > + if (!cpudata)
> > + return -ENOMEM;
> > + WRITE_ONCE(all_cpu_data[cpunum], cpudata);
> > +
> > + cpudata->cpu = cpunum;
> > +
> > + if (cppc_active) {
> > + if (amd_pstate_acpi_pm_profile_server())
> > + cppc_boost = true;
> > + }
> > +
> > + }
> > + cpudata->epp_powersave = -EINVAL;
> > + cpudata->epp_policy = 0;
> > + pr_debug("controlling: cpu %d\n", cpunum);
> > + return 0;
> > +}
> > +
> > +static int __amd_pstate_cpu_init(struct cpufreq_policy *policy) {
> > + int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret;
> > + struct amd_cpudata *cpudata;
> > + struct device *dev;
> > + int rc;
> > + u64 value;
> > +
> > + rc = amd_pstate_init_cpu(policy->cpu);
> > + if (rc)
> > + return rc;
> > +
> > + cpudata = all_cpu_data[policy->cpu];
> > +
> > + dev = get_cpu_device(policy->cpu);
> > + if (!dev)
> > + goto free_cpudata1;
> > +
> > + rc = amd_pstate_init_perf(cpudata);
> > + if (rc)
> > + goto free_cpudata1;
> > +
> > + min_freq = amd_get_min_freq(cpudata);
> > + max_freq = amd_get_max_freq(cpudata);
> > + nominal_freq = amd_get_nominal_freq(cpudata);
> > + lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
> > + if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
> > + dev_err(dev, "min_freq(%d) or max_freq(%d) value is
> incorrect\n",
> > + min_freq, max_freq);
> > + ret = -EINVAL;
> > + goto free_cpudata1;
> > + }
> > +
> > + policy->min = min_freq;
> > + policy->max = max_freq;
> > +
> > + policy->cpuinfo.min_freq = min_freq;
> > + policy->cpuinfo.max_freq = max_freq;
> > + /* It will be updated by governor */
> > + policy->cur = policy->cpuinfo.min_freq;
> > +
> > + /* Initial processor data capability frequencies */
> > + cpudata->max_freq = max_freq;
> > + cpudata->min_freq = min_freq;
> > + cpudata->nominal_freq = nominal_freq;
> > + cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
> > +
> > + policy->driver_data = cpudata;
> > +
> > + update_boost_state();
> > + cpudata->epp_cached = amd_pstate_get_epp(cpudata, value);
> > +
> > + policy->min = policy->cpuinfo.min_freq;
> > + policy->max = policy->cpuinfo.max_freq;
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC))
> > + policy->fast_switch_possible = true;
> > +
> > + if (boot_cpu_has(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 = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1,
> &value);
> > + if (ret)
> > + return ret;
> > + WRITE_ONCE(cpudata->cppc_cap1_cached, value);
> > + }
> > + amd_pstate_boost_init(cpudata);
> > +
> > + return 0;
> > +
> > +free_cpudata1:
> > + kfree(cpudata);
> > + return ret;
> > +}
> > +
> > +static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) {
> > + int ret;
> > +
> > + ret = __amd_pstate_cpu_init(policy);
> > + if (ret)
> > + return ret;
> > + /*
> > + * Set the policy to powersave to provide a valid fallback value in case
> > + * the default cpufreq governor is neither powersave nor
> performance.
> > + */
> > + policy->policy = CPUFREQ_POLICY_POWERSAVE;
> > +
> > + return 0;
> > +}
> > +
> > +static int amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy) {
> > + pr_debug("CPU %d exiting\n", policy->cpu);
> > + policy->fast_switch_possible = false;
> > + return 0;
> > +}
> > +
> > +static void amd_pstate_update_max_freq(unsigned int cpu) {
> > + struct cpufreq_policy *policy = policy = cpufreq_cpu_get(cpu);
> > +
> > + if (!policy)
> > + return;
> > +
> > + refresh_frequency_limits(policy);
> > + cpufreq_cpu_put(policy);
> > +}
> > +
> > +static void amd_pstate_epp_update_limits(unsigned int cpu) {
> > + mutex_lock(&amd_pstate_driver_lock);
> > + update_boost_state();
> > + if (global_params.cppc_boost_disabled) {
> > + for_each_possible_cpu(cpu)
> > + amd_pstate_update_max_freq(cpu);
> > + } else {
> > + cpufreq_update_policy(cpu);
> > + }
> > + mutex_unlock(&amd_pstate_driver_lock);
> > +}
> > +
> > +static int cppc_boost_hold_time_ns = 3 * NSEC_PER_MSEC;
> > +
> > +static inline void amd_pstate_boost_up(struct amd_cpudata *cpudata) {
> > + u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
> > + u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
> > + u32 max_limit = (hwp_req & 0xff);
> > + u32 min_limit = (hwp_req & 0xff00) >> 8;
> > + u32 boost_level1;
> > +
> > + /* If max and min are equal or already at max, nothing to boost */
> > + if (max_limit == min_limit)
> > + return;
> > +
> > + /* Set boost max and min to initial value */
> > + if (!cpudata->cppc_boost_min)
> > + cpudata->cppc_boost_min = min_limit;
> > +
> > + boost_level1 = ((AMD_CPPC_NOMINAL_PERF(hwp_cap) +
> min_limit) >> 1);
> > +
> > + if (cpudata->cppc_boost_min < boost_level1)
> > + cpudata->cppc_boost_min = boost_level1;
> > + else if (cpudata->cppc_boost_min <
> AMD_CPPC_NOMINAL_PERF(hwp_cap))
> > + cpudata->cppc_boost_min =
> AMD_CPPC_NOMINAL_PERF(hwp_cap);
> > + else if (cpudata->cppc_boost_min ==
> AMD_CPPC_NOMINAL_PERF(hwp_cap))
> > + cpudata->cppc_boost_min = max_limit;
> > + else
> > + return;
> > +
> > + hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
> > + hwp_req |= AMD_CPPC_MIN_PERF(cpudata->cppc_boost_min);
> > + wrmsrl(MSR_AMD_CPPC_REQ, hwp_req);
> > + cpudata->last_update = cpudata->sample.time; }
> > +
> > +static inline void amd_pstate_boost_down(struct amd_cpudata *cpudata)
> > +{
> > + bool expired;
> > +
> > + if (cpudata->cppc_boost_min) {
> > + expired = time_after64(cpudata->sample.time, cpudata-
> >last_update +
> > + cppc_boost_hold_time_ns);
> > +
> > + if (expired) {
> > + wrmsrl(MSR_AMD_CPPC_REQ, cpudata-
> >cppc_req_cached);
> > + cpudata->cppc_boost_min = 0;
> > + }
> > + }
> > +
> > + cpudata->last_update = cpudata->sample.time; }
> > +
> > +static inline void amd_pstate_boost_update_util(struct amd_cpudata
> *cpudata,
> > + u64 time)
> > +{
> > + cpudata->sample.time = time;
> > + if (smp_processor_id() != cpudata->cpu)
> > + return;
> > +
> > + if (cpudata->sched_flags & SCHED_CPUFREQ_IOWAIT) {
> > + bool do_io = false;
> > +
> > + cpudata->sched_flags = 0;
> > + /*
> > + * Set iowait_boost flag and update time. Since IO WAIT flag
> > + * is set all the time, we can't just conclude that there is
> > + * some IO bound activity is scheduled on this CPU with just
> > + * one occurrence. If we receive at least two in two
> > + * consecutive ticks, then we treat as boost candidate.
> > + * This is leveraged from Intel Pstate driver.
> > + */
> > + if (time_before64(time, cpudata->last_io_update + 2 *
> TICK_NSEC))
> > + do_io = true;
> > +
> > + cpudata->last_io_update = time;
> > +
> > + if (do_io)
> > + amd_pstate_boost_up(cpudata);
> > +
> > + } else {
> > + amd_pstate_boost_down(cpudata);
> > + }
> > +}
> > +
> > +static inline void amd_pstate_cppc_update_hook(struct update_util_data
> *data,
> > + u64 time, unsigned int flags)
> > +{
> > + struct amd_cpudata *cpudata = container_of(data,
> > + struct amd_cpudata, update_util);
> > +
> > + cpudata->sched_flags |= flags;
> > +
> > + if (smp_processor_id() == cpudata->cpu)
> > + amd_pstate_boost_update_util(cpudata, time); }
> > +
> > +static void amd_pstate_clear_update_util_hook(unsigned int cpu) {
> > + struct amd_cpudata *cpudata = all_cpu_data[cpu];
> > +
> > + if (!cpudata->update_util_set)
> > + return;
> > +
> > + cpufreq_remove_update_util_hook(cpu);
> > + cpudata->update_util_set = false;
> > + synchronize_rcu();
> > +}
> > +
> > +static void amd_pstate_set_update_util_hook(unsigned int cpu_num) {
> > + struct amd_cpudata *cpudata = all_cpu_data[cpu_num];
> > +
> > + if (!cppc_boost) {
> > + if (cpudata->update_util_set)
> > + amd_pstate_clear_update_util_hook(cpudata->cpu);
> > + return;
> > + }
> > +
> > + if (cpudata->update_util_set)
> > + return;
> > +
> > + cpudata->sample.time = 0;
> > + cpufreq_add_update_util_hook(cpu_num, &cpudata->update_util,
> > +
> amd_pstate_cppc_update_hook);
> > + cpudata->update_util_set = true;
> > +}
> > +
> > +static void amd_pstate_epp_init(unsigned int cpu) {
> > + struct amd_cpudata *cpudata = all_cpu_data[cpu];
> > + u32 max_perf, min_perf;
> > + u64 value;
> > + s16 epp;
> > + int ret;
> > +
> > + max_perf = READ_ONCE(cpudata->highest_perf);
> > + min_perf = READ_ONCE(cpudata->lowest_perf);
> > +
> > + value = READ_ONCE(cpudata->cppc_req_cached);
> > +
> > + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
> > + min_perf = max_perf;
> > +
> > + /* Initial min/max values for CPPC Performance Controls Register */
> > + value &= ~AMD_CPPC_MIN_PERF(~0L);
> > + value |= AMD_CPPC_MIN_PERF(min_perf);
> > +
> > + value &= ~AMD_CPPC_MAX_PERF(~0L);
> > + value |= AMD_CPPC_MAX_PERF(max_perf);
> > +
> > + /* CPPC EPP feature require to set zero to the desire perf bit */
> > + value &= ~AMD_CPPC_DES_PERF(~0L);
> > + value |= AMD_CPPC_DES_PERF(0);
> > +
> > + if (cpudata->epp_policy == cpudata->policy)
> > + goto skip_epp;
> > +
> > + cpudata->epp_policy = cpudata->policy;
> > +
> > + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> > + epp = amd_pstate_get_epp(cpudata, value);
> > + cpudata->epp_powersave = epp;
> > + if (epp < 0)
> > + goto skip_epp;
> > + /* force the epp value to be zero for performance policy */
> > + epp = 0;
> > + } else {
> > + if (cpudata->epp_powersave < 0)
> > + goto skip_epp;
> > + /* Get BIOS pre-defined epp value */
> > + epp = amd_pstate_get_epp(cpudata, value);
> > + if (epp)
> > + goto skip_epp;
> > + epp = cpudata->epp_powersave;
> > + }
> > + /* Set initial EPP value */
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > + value &= ~GENMASK_ULL(31, 24);
> > + value |= (u64)epp << 24;
> > + }
> > +
> > +skip_epp:
> > + WRITE_ONCE(cpudata->cppc_req_cached, value);
> > + ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> > + if (!ret)
> > + cpudata->epp_cached = epp;
> > +}
> > +
> > +static void amd_pstate_set_max_limits(struct amd_cpudata *cpudata) {
> > + u64 hwp_cap = READ_ONCE(cpudata->cppc_cap1_cached);
> > + u64 hwp_req = READ_ONCE(cpudata->cppc_req_cached);
> > + u32 max_limit = (hwp_cap >> 24) & 0xff;
> > +
> > + hwp_req &= ~AMD_CPPC_MIN_PERF(~0L);
> > + hwp_req |= AMD_CPPC_MIN_PERF(max_limit);
> > + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, hwp_req); }
> > +
> > +static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) {
> > + struct amd_cpudata *cpudata;
> > +
> > + if (!policy->cpuinfo.max_freq)
> > + return -ENODEV;
> > +
> > + pr_debug("set_policy: cpuinfo.max %u policy->max %u\n",
> > + policy->cpuinfo.max_freq, policy->max);
> > +
> > + cpudata = all_cpu_data[policy->cpu];
> > + cpudata->policy = policy->policy;
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC)) {
>
> X86_FEATURE_CPPC indicated the MSR support, but I believe the share
> memory CPU also has the EPP, right?
Yes, the shared memory system which are using below preferred profile will add the util hook with another patchset.
Current I would like to add this to MSR systems in this patchset as tight schedule.
if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
>
> > + mutex_lock(&amd_pstate_limits_lock);
> > +
> > + if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) {
> > + amd_pstate_clear_update_util_hook(policy->cpu);
> > + amd_pstate_set_max_limits(cpudata);
> > + } else {
> > + amd_pstate_set_update_util_hook(policy->cpu);
>
> May I know why amd processors also needs to set and update util hook?
Like intel already implemented this scheduler hook, it helps to improve the I/O performance, it is not enabled by default for Client CPU.
>
> > + }
> > +
> > + if (boot_cpu_has(X86_FEATURE_CPPC))
>
> I am confused why if (boot_cpu_has(X86_FEATURE_CPPC) is still inside of a if
> (boot_cpu_has(X86_FEATURE_CPPC)).
>
Fixed in V7.
> > + amd_pstate_epp_init(policy->cpu);
> > +
> > + mutex_unlock(&amd_pstate_limits_lock);
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static void amd_pstate_verify_cpu_policy(struct amd_cpudata *cpudata,
> > + struct cpufreq_policy_data *policy)
> {
> > + update_boost_state();
> > + cpufreq_verify_within_cpu_limits(policy);
> > +}
> > +
> > +static int amd_pstate_epp_verify_policy(struct cpufreq_policy_data
> > +*policy) {
> > + amd_pstate_verify_cpu_policy(all_cpu_data[policy->cpu], policy);
> > + pr_debug("policy_max =%d, policy_min=%d\n", policy->max, policy-
> >min);
> > + return 0;
> > +}
> > +
> > static struct cpufreq_driver amd_pstate_driver = {
> > .flags = CPUFREQ_CONST_LOOPS |
> CPUFREQ_NEED_UPDATE_LIMITS,
> > .verify = amd_pstate_verify,
> > @@ -616,8 +1224,20 @@ static struct cpufreq_driver amd_pstate_driver =
> {
> > .attr = amd_pstate_attr,
> > };
> >
> > +static struct cpufreq_driver amd_pstate_epp_driver = {
> > + .flags = CPUFREQ_CONST_LOOPS,
> > + .verify = amd_pstate_epp_verify_policy,
> > + .setpolicy = amd_pstate_epp_set_policy,
> > + .init = amd_pstate_epp_cpu_init,
> > + .exit = amd_pstate_epp_cpu_exit,
> > + .update_limits = amd_pstate_epp_update_limits,
> > + .name = "amd_pstate_epp",
> > + .attr = amd_pstate_epp_attr,
> > +};
> > +
> > static int __init amd_pstate_init(void) {
> > + static struct amd_cpudata **cpudata;
> > int ret;
> >
> > if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) @@ -644,7
> +1264,8 @@
> > static int __init amd_pstate_init(void)
> > /* capability check */
> > if (boot_cpu_has(X86_FEATURE_CPPC)) {
> > pr_debug("AMD CPPC MSR based functionality is
> supported\n");
> > - amd_pstate_driver.adjust_perf = amd_pstate_adjust_perf;
> > + if (!cppc_active)
> > + default_pstate_driver->adjust_perf =
> amd_pstate_adjust_perf;
> > } else {
> > pr_debug("AMD CPPC shared memory based functionality is
> supported\n");
> > static_call_update(amd_pstate_enable, cppc_enable); @@ -
> 652,6
> > +1273,10 @@ static int __init amd_pstate_init(void)
> > static_call_update(amd_pstate_update_perf,
> cppc_update_perf);
> > }
> >
> > + cpudata = vzalloc(array_size(sizeof(void *), num_possible_cpus()));
> > + if (!cpudata)
> > + return -ENOMEM;
> > + WRITE_ONCE(all_cpu_data, cpudata);
> > /* enable amd pstate feature */
> > ret = amd_pstate_enable(true);
> > if (ret) {
> > @@ -659,9 +1284,9 @@ static int __init amd_pstate_init(void)
> > return ret;
> > }
> >
> > - ret = cpufreq_register_driver(&amd_pstate_driver);
> > + ret = cpufreq_register_driver(default_pstate_driver);
> > if (ret)
> > - pr_err("failed to register amd_pstate_driver with
> return %d\n",
> > + pr_err("failed to register amd pstate driver with
> return %d\n",
> > ret);
> >
> > return ret;
> > @@ -676,8 +1301,14 @@ static int __init amd_pstate_param(char *str)
> > if (!strcmp(str, "disable")) {
> > cppc_load = 0;
> > pr_info("driver is explicitly disabled\n");
> > - } else if (!strcmp(str, "passive"))
> > + } else if (!strcmp(str, "passive")) {
> > cppc_load = 1;
> > + default_pstate_driver = &amd_pstate_driver;
> > + } else if (!strcmp(str, "active")) {
> > + cppc_active = 1;
> > + cppc_load = 1;
> > + default_pstate_driver = &amd_pstate_epp_driver;
> > + }
> >
> > return 0;
> > }
> > diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h
> > index 1c4b8659f171..888af62040f1 100644
> > --- a/include/linux/amd-pstate.h
> > +++ b/include/linux/amd-pstate.h
> > @@ -25,6 +25,7 @@ struct amd_aperf_mperf {
> > u64 aperf;
> > u64 mperf;
> > u64 tsc;
> > + u64 time;
> > };
> >
> > /**
> > @@ -47,6 +48,18 @@ struct amd_aperf_mperf {
> > * @prev: Last Aperf/Mperf/tsc count value read from register
> > * @freq: current cpu frequency value
> > * @boost_supported: check whether the Processor or SBIOS supports
> > boost mode
> > + * @epp_powersave: Last saved CPPC energy performance preference
> > + when policy switched to performance
> > + * @epp_policy: Last saved policy used to set energy-performance
> > +preference
> > + * @epp_cached: Cached CPPC energy-performance preference value
> > + * @policy: Cpufreq policy value
> > + * @sched_flags: Store scheduler flags for possible cross CPU update
> > + * @update_util_set: CPUFreq utility callback is set
> > + * @last_update: Time stamp of the last performance state update
> > + * @cppc_boost_min: Last CPPC boosted min performance state
> > + * @cppc_cap1_cached: Cached value of the last CPPC Capabilities MSR
> > + * @update_util: Cpufreq utility callback information
> > + * @sample: the stored performance sample
> > *
> > * The amd_cpudata is key private data for each CPU thread in AMD P-
> State, and
> > * represents all the attributes and goals that AMD P-State requests at
> runtime.
> > @@ -72,6 +85,28 @@ struct amd_cpudata {
> >
> > u64 freq;
> > bool boost_supported;
> > +
> > + /* EPP feature related attributes*/
> > + s16 epp_powersave;
> > + s16 epp_policy;
> > + s16 epp_cached;
> > + u32 policy;
> > + u32 sched_flags;
> > + bool update_util_set;
> > + u64 last_update;
> > + u64 last_io_update;
> > + u32 cppc_boost_min;
> > + u64 cppc_cap1_cached;
> > + struct update_util_data update_util;
> > + struct amd_aperf_mperf sample;
> > +};
> > +
> > +/**
> > + * struct amd_pstate_params - global parameters for the performance
> > +control
> > + * @ cppc_boost_disabled wheher the core performance boost disabled
> > +*/ struct amd_pstate_params {
> > + bool cppc_boost_disabled;
> > };
> >
> > #endif /* _LINUX_AMD_PSTATE_H */
> > --
> > 2.34.1
> >