[PATCH v3 06/11] x86/amd: Move amd_get_highest_perf() out of amd-pstate

From: Mario Limonciello
Date: Thu Sep 05 2024 - 12:31:47 EST


From: Mario Limonciello <mario.limonciello@xxxxxxx>

amd_pstate_get_highest_perf() is a helper used to get the highest perf
value on AMD systems. It's used in amd-pstate as part of preferred
core handling, but applicable for acpi-cpufreq as well.

Move it out to cppc handling code as amd_get_highest_perf().

Reviewed-by: Perry Yuan <perry.yuan@xxxxxxx>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@xxxxxxx>
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v1->v2:
* Update commit message (Gautham)
---
arch/x86/kernel/acpi/cppc.c | 30 ++++++++++++++++++++++++++++++
drivers/cpufreq/amd-pstate.c | 34 ++--------------------------------
include/acpi/cppc_acpi.h | 5 +++++
3 files changed, 37 insertions(+), 32 deletions(-)

diff --git a/arch/x86/kernel/acpi/cppc.c b/arch/x86/kernel/acpi/cppc.c
index f0328ce98a8fe..a75dcb382c786 100644
--- a/arch/x86/kernel/acpi/cppc.c
+++ b/arch/x86/kernel/acpi/cppc.c
@@ -116,6 +116,36 @@ void init_freq_invariance_cppc(void)
mutex_unlock(&freq_invariance_lock);
}

+/*
+ * Get the highest performance register value.
+ * @cpu: CPU from which to get highest performance.
+ * @highest_perf: Return address for highest performance value.
+ *
+ * Return: 0 for success, negative error code otherwise.
+ */
+int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf)
+{
+ u64 val;
+ int ret;
+
+ if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
+ ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &val);
+ if (ret)
+ goto out;
+
+ val = AMD_CPPC_HIGHEST_PERF(val);
+ } else {
+ ret = cppc_get_highest_perf(cpu, &val);
+ if (ret)
+ goto out;
+ }
+
+ WRITE_ONCE(*highest_perf, (u32)val);
+out:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(amd_get_highest_perf);
+
/**
* amd_get_boost_ratio_numerator: Get the numerator to use for boost ratio calculation
* @cpu: CPU to get numerator for.
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index db4f747f128f1..44df6ef66b5fa 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -803,36 +803,6 @@ static void amd_pstste_sched_prefcore_workfn(struct work_struct *work)
}
static DECLARE_WORK(sched_prefcore_work, amd_pstste_sched_prefcore_workfn);

-/*
- * Get the highest performance register value.
- * @cpu: CPU from which to get highest performance.
- * @highest_perf: Return address.
- *
- * Return: 0 for success, -EIO otherwise.
- */
-static int amd_pstate_get_highest_perf(int cpu, u32 *highest_perf)
-{
- int ret;
-
- if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
- u64 cap1;
-
- ret = rdmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_CAP1, &cap1);
- if (ret)
- return ret;
- WRITE_ONCE(*highest_perf, AMD_CPPC_HIGHEST_PERF(cap1));
- } else {
- u64 cppc_highest_perf;
-
- ret = cppc_get_highest_perf(cpu, &cppc_highest_perf);
- if (ret)
- return ret;
- WRITE_ONCE(*highest_perf, cppc_highest_perf);
- }
-
- return (ret);
-}
-
#define CPPC_MAX_PERF U8_MAX

static void amd_pstate_init_prefcore(struct amd_cpudata *cpudata)
@@ -840,7 +810,7 @@ static void amd_pstate_init_prefcore(struct amd_cpudata *cpudata)
int ret, prio;
u32 highest_perf;

- ret = amd_pstate_get_highest_perf(cpudata->cpu, &highest_perf);
+ ret = amd_get_highest_perf(cpudata->cpu, &highest_perf);
if (ret)
return;

@@ -879,7 +849,7 @@ static void amd_pstate_update_limits(unsigned int cpu)
if ((!amd_pstate_prefcore) || (!cpudata->hw_prefcore))
goto free_cpufreq_put;

- ret = amd_pstate_get_highest_perf(cpu, &cur_high);
+ ret = amd_get_highest_perf(cpu, &cur_high);
if (ret)
goto free_cpufreq_put;

diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
index 97861abc5f5b8..f7c7abf2a95e9 100644
--- a/include/acpi/cppc_acpi.h
+++ b/include/acpi/cppc_acpi.h
@@ -159,6 +159,7 @@ extern int cppc_get_epp_perf(int cpunum, u64 *epp_perf);
extern int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable);
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);
#else /* !CONFIG_ACPI_CPPC_LIB */
static inline int cppc_get_desired_perf(int cpunum, u64 *desired_perf)
@@ -233,6 +234,10 @@ static inline int cppc_get_auto_sel_caps(int cpunum, struct cppc_perf_caps *perf
{
return -EOPNOTSUPP;
}
+static inline int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf)
+{
+ return -ENODEV;
+}
static inline int amd_get_boost_ratio_numerator(unsigned int cpu, u64 *numerator)
{
return -EOPNOTSUPP;
--
2.43.0