@@ -9,6 +9,16 @@
#include <asm/processor.h>
#include <asm/topology.h>
+#define CPPC_HIGHEST_PERF_PREFCORE 166
+
+enum amd_pref_core {
+ AMD_PREF_CORE_UNKNOWN = 0,
+ AMD_PREF_CORE_SUPPORTED,
+ AMD_PREF_CORE_UNSUPPORTED,
+};
+static enum amd_pref_core amd_pref_core_detected;
+static u64 boost_numerator;
+
/* Refer to drivers/acpi/cppc_acpi.c for the description of functions */
bool cpc_supported_by_cpu(void)
@@ -146,6 +156,66 @@ int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf)
}
EXPORT_SYMBOL_GPL(amd_get_highest_perf);
+/**
+ * amd_detect_prefcore: Detect if CPUs in the system support preferred cores
+ * @detected: Output variable for the result of the detection.
+ *
+ * Determine whether CPUs in the system support preferred cores. On systems
+ * that support preferred cores, different highest perf values will be found
+ * on different cores. On other systems, the highest perf value will be the
+ * same on all cores.
+ *
+ * The result of the detection will be stored in the 'detected' parameter.
+ *
+ * Return: 0 for success, negative error code otherwise
+ */
+int amd_detect_prefcore(bool *detected)
+{
+ int cpu, count = 0;
+ u64 highest_perf[2] = {0};
+
+ if (WARN_ON(!detected))
+ return -EINVAL;
+
+ switch (amd_pref_core_detected) {
+ case AMD_PREF_CORE_SUPPORTED:
+ *detected = true;
+ return 0;
+ case AMD_PREF_CORE_UNSUPPORTED:
+ *detected = false;
+ return 0;
+ default:
+ break;
+ }
+
+ for_each_present_cpu(cpu) {
+ u32 tmp;
+ int ret;
+
+ ret = amd_get_highest_perf(cpu, &tmp);
+ if (ret)
+ return ret;
+
+ if (!count || (count == 1 && tmp != highest_perf[0]))
+ highest_perf[count++] = tmp;
+
+ if (count == 2)
+ break;
+ }
+
+ *detected = (count == 2);
+ boost_numerator = highest_perf[0];
+
+ amd_pref_core_detected = *detected ? AMD_PREF_CORE_SUPPORTED :
+ AMD_PREF_CORE_UNSUPPORTED;
+
+ pr_debug("AMD CPPC preferred core is %ssupported (highest perf: 0x%llx)\n",
+ *detected ? "" : "un", highest_perf[0]);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(amd_detect_prefcore);
+
/**
* amd_get_boost_ratio_numerator: Get the numerator to use for boost ratio calculation
* @cpu: CPU to get numerator for.
@@ -155,24 +225,27 @@ EXPORT_SYMBOL_GPL(amd_get_highest_perf);
* a CPU. On systems that support preferred cores, this will be a hardcoded
* value. On other systems this will the highest performance register value.
*
+ * If booting the system with amd-pstate enabled but preferred cores disabled then
+ * the correct boost numerator will be returned to match hardware capabilities
+ * even if the preferred cores scheduling hints are not enabled.
+ *
* Return: 0 for success, negative error code otherwise.
*/
int amd_get_boost_ratio_numerator(unsigned int cpu, u64 *numerator)
{
- struct cpuinfo_x86 *c = &boot_cpu_data;
+ bool prefcore;
+ int ret;
- if (c->x86 == 0x17 && ((c->x86_model >= 0x30 && c->x86_model < 0x40) ||
- (c->x86_model >= 0x70 && c->x86_model < 0x80))) {
- *numerator = 166;
- return 0;
- }
+ ret = amd_detect_prefcore(&prefcore);
+ if (ret)
+ return ret;
- if (c->x86 == 0x19 && ((c->x86_model >= 0x20 && c->x86_model < 0x30) ||
- (c->x86_model >= 0x40 && c->x86_model < 0x70))) {
- *numerator = 166;
+ /* without preferred cores, return the highest perf register value */
+ if (!prefcore) {
+ *numerator = boost_numerator;
return 0;
}
- *numerator = 255;
+ *numerator = CPPC_HIGHEST_PERF_PREFCORE;
return 0;
}
@@ -807,32 +807,18 @@ static DECLARE_WORK(sched_prefcore_work, amd_pstste_sched_prefcore_workfn);
static void amd_pstate_init_prefcore(struct amd_cpudata *cpudata)
{
- int ret, prio;
- u32 highest_perf;
-
- ret = amd_get_highest_perf(cpudata->cpu, &highest_perf);
- if (ret)
+ /* user disabled or not detected */
+ if (!amd_pstate_prefcore)
return;
cpudata->hw_prefcore = true;
- /* check if CPPC preferred core feature is enabled*/
- if (highest_perf < CPPC_MAX_PERF)
- prio = (int)highest_perf;
- else {
- pr_debug("AMD CPPC preferred core is unsupported!\n");
- cpudata->hw_prefcore = false;
- return;
- }
-
- if (!amd_pstate_prefcore)
- return;
/*
* The priorities can be set regardless of whether or not
* sched_set_itmt_support(true) has been called and it is valid to
* update them at any time after it has been called.
*/
- sched_set_itmt_core_prio(prio, cpudata->cpu);
+ sched_set_itmt_core_prio((int)READ_ONCE(cpudata->highest_perf), cpudata->cpu);
schedule_work(&sched_prefcore_work);
}
@@ -998,12 +984,12 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
cpudata->cpu = policy->cpu;
- amd_pstate_init_prefcore(cpudata);
-
ret = amd_pstate_init_perf(cpudata);
if (ret)
goto free_cpudata1;
+ amd_pstate_init_prefcore(cpudata);
+
ret = amd_pstate_init_freq(cpudata);
if (ret)
goto free_cpudata1;
@@ -1453,12 +1439,12 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
cpudata->cpu = policy->cpu;
cpudata->epp_policy = 0;
- amd_pstate_init_prefcore(cpudata);
-
ret = amd_pstate_init_perf(cpudata);
if (ret)
goto free_cpudata1;
+ amd_pstate_init_prefcore(cpudata);
+
ret = amd_pstate_init_freq(cpudata);
if (ret)
goto free_cpudata1;
@@ -1920,6 +1906,12 @@ static int __init amd_pstate_init(void)
static_call_update(amd_pstate_update_perf, cppc_update_perf);
}
+ if (amd_pstate_prefcore) {
+ ret = amd_detect_prefcore(&amd_pstate_prefcore);
+ if (ret)
+ return ret;
+ }
+
/* enable amd pstate feature */
ret = amd_pstate_enable(true);
if (ret) {
@@ -161,6 +161,7 @@ extern int cppc_get_auto_sel_caps(int cpunum, struct cppc_perf_caps *perf_caps);
extern int cppc_set_auto_sel(int cpu, bool enable);
extern int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf);
extern int amd_get_boost_ratio_numerator(unsigned int cpu, u64 *numerator);
+extern int amd_detect_prefcore(bool *detected);
#else /* !CONFIG_ACPI_CPPC_LIB */
static inline int cppc_get_desired_perf(int cpunum, u64 *desired_perf)
{
@@ -242,6 +243,10 @@ static inline int amd_get_boost_ratio_numerator(unsigned int cpu, u64 *numerator
{
return -EOPNOTSUPP;
}
+static inline int amd_detect_prefcore(bool *detected)
+{
+ return -ENODEV;
+}
#endif /* !CONFIG_ACPI_CPPC_LIB */
#endif /* _CPPC_ACPI_H*/