[PATCH v3 2/4] ACPI: CPPC: Make autonomous selection helpers take a u64

From: Sumit Gupta

Date: Fri Jul 24 2026 - 18:02:45 EST


cppc_get_auto_sel()/cppc_set_auto_sel() use a bool, unlike the other
CPPC register get/set helpers which use a u64.

The next patch in this series saves and restores the OSPM-set registers
across CPU hotplug and driver unload through a common table of register
get/set helpers that all take a u64. The bool autonomous selection
helpers cannot be added to that table.

Change cppc_get_auto_sel()/cppc_set_auto_sel() to take a u64 so the
autonomous selection register fits alongside the others, and update
their callers.

Signed-off-by: Sumit Gupta <sumitg@xxxxxxxxxx>
---
drivers/acpi/cppc_acpi.c | 20 ++++----------------
drivers/cpufreq/amd-pstate.c | 2 +-
drivers/cpufreq/cppc_cpufreq.c | 4 ++--
include/acpi/cppc_acpi.h | 8 ++++----
4 files changed, 11 insertions(+), 23 deletions(-)

diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 9f572f481241..ffadd2ca26b1 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -1757,23 +1757,11 @@ EXPORT_SYMBOL_GPL(cppc_set_auto_act_window);
/**
* cppc_get_auto_sel() - Read autonomous selection register.
* @cpu: CPU from which to read register.
- * @enable: Return address.
+ * @enable: Return address, set to 0 or 1.
*/
-int cppc_get_auto_sel(int cpu, bool *enable)
+int cppc_get_auto_sel(int cpu, u64 *enable)
{
- u64 auto_sel;
- int ret;
-
- if (enable == NULL)
- return -EINVAL;
-
- ret = cppc_get_reg_val(cpu, AUTO_SEL_ENABLE, &auto_sel);
- if (ret)
- return ret;
-
- *enable = (bool)auto_sel;
-
- return 0;
+ return cppc_get_reg_val(cpu, AUTO_SEL_ENABLE, enable);
}
EXPORT_SYMBOL_GPL(cppc_get_auto_sel);

@@ -1782,7 +1770,7 @@ EXPORT_SYMBOL_GPL(cppc_get_auto_sel);
* @cpu : CPU to which to write register.
* @enable : the desired value of autonomous selection resiter to be updated.
*/
-int cppc_set_auto_sel(int cpu, bool enable)
+int cppc_set_auto_sel(int cpu, u64 enable)
{
return cppc_set_reg_val(cpu, AUTO_SEL_ENABLE, enable);
}
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index f8d8288d644f..0f99bb86c3a3 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -507,7 +507,7 @@ static int shmem_init_perf(struct amd_cpudata *cpudata)
struct cppc_perf_caps cppc_perf;
union perf_cached perf = READ_ONCE(cpudata->perf);
u64 numerator;
- bool auto_sel;
+ u64 auto_sel;

int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
if (ret)
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index 6dc59f99d880..34cdba00e61a 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -893,7 +893,7 @@ static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)

static ssize_t show_auto_select(struct cpufreq_policy *policy, char *buf)
{
- bool val;
+ u64 val;
int ret;

ret = cppc_get_auto_sel(policy->cpu, &val);
@@ -905,7 +905,7 @@ static ssize_t show_auto_select(struct cpufreq_policy *policy, char *buf)
if (ret)
return ret;

- return sysfs_emit(buf, "%d\n", val);
+ return sysfs_emit(buf, "%llu\n", val);
}

static ssize_t store_auto_select(struct cpufreq_policy *policy,
diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
index 8693890a7275..f4da73876287 100644
--- a/include/acpi/cppc_acpi.h
+++ b/include/acpi/cppc_acpi.h
@@ -182,8 +182,8 @@ extern int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool e
extern int cppc_set_epp(int cpu, u64 epp_val);
extern int cppc_get_auto_act_window(int cpu, u64 *auto_act_window);
extern int cppc_set_auto_act_window(int cpu, u64 auto_act_window);
-extern int cppc_get_auto_sel(int cpu, bool *enable);
-extern int cppc_set_auto_sel(int cpu, bool enable);
+extern int cppc_get_auto_sel(int cpu, u64 *enable);
+extern int cppc_set_auto_sel(int cpu, u64 enable);
extern int cppc_get_perf_limited(int cpu, u64 *perf_limited);
extern int cppc_set_perf_limited(int cpu, u64 bits_to_clear);
extern int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf);
@@ -274,11 +274,11 @@ static inline int cppc_set_auto_act_window(int cpu, u64 auto_act_window)
{
return -EOPNOTSUPP;
}
-static inline int cppc_get_auto_sel(int cpu, bool *enable)
+static inline int cppc_get_auto_sel(int cpu, u64 *enable)
{
return -EOPNOTSUPP;
}
-static inline int cppc_set_auto_sel(int cpu, bool enable)
+static inline int cppc_set_auto_sel(int cpu, u64 enable)
{
return -EOPNOTSUPP;
}
--
2.34.1