Add support for getting the highest performance to the generic CPPC driver. This enables downstream drivers such as amd-pstate to discover and use these values.
Please refer to Chapter 8.4.6.1.1.1. Highest Performance of ACPI Specification 6.5 for details on continuous performance control of CPPC. Also see the Link below.
Tested-by: Oleksandr Natalenko oleksandr@natalenko.name Reviewed-by: Mario Limonciello mario.limonciello@amd.com Reviewed-by: Wyes Karny wyes.karny@amd.com Reviewed-by: Perry Yuan perry.yuan@amd.com Acked-by: Huang Rui ray.huang@amd.com Signed-off-by: Meng Li li.meng@amd.com Link: https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html?... --- drivers/acpi/cppc_acpi.c | 13 +++++++++++++ include/acpi/cppc_acpi.h | 5 +++++ 2 files changed, 18 insertions(+)
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index d155a86a8614..a50e70abdf19 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -1157,6 +1157,19 @@ int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf) return cppc_get_perf(cpunum, NOMINAL_PERF, nominal_perf); }
+/** + * cppc_get_highest_perf - Get the highest performance register value. + * @cpunum: CPU from which to get highest performance. + * @highest_perf: Return address. + * + * Return: 0 for success, -EIO otherwise. + */ +int cppc_get_highest_perf(int cpunum, u64 *highest_perf) +{ + return cppc_get_perf(cpunum, HIGHEST_PERF, highest_perf); +} +EXPORT_SYMBOL_GPL(cppc_get_highest_perf); + /** * cppc_get_epp_perf - Get the epp register value. * @cpunum: CPU from which to get epp preference value. diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h index 3a0995f8bce8..930b6afba6f4 100644 --- a/include/acpi/cppc_acpi.h +++ b/include/acpi/cppc_acpi.h @@ -139,6 +139,7 @@ struct cppc_cpudata { #ifdef CONFIG_ACPI_CPPC_LIB extern int cppc_get_desired_perf(int cpunum, u64 *desired_perf); extern int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf); +extern int cppc_get_highest_perf(int cpunum, u64 *highest_perf); extern int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs); extern int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls); extern int cppc_set_enable(int cpu, bool enable); @@ -167,6 +168,10 @@ static inline int cppc_get_nominal_perf(int cpunum, u64 *nominal_perf) { return -ENOTSUPP; } +static inline int cppc_get_highest_perf(int cpunum, u64 *highest_perf) +{ + return -ENOTSUPP; +} static inline int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs) { return -ENOTSUPP;