Users are having more success with amd-pstate since the introduction of EPP and Guided modes. To expose the driver to more users by default introduce a kernel configuration option for setting the default mode. Users can use an integer to map out which default mode they want to use in lieu of a kernel command line option. This will default to EPP, but only if: 1) The CPU supports an MSR. 2) The system profile is identified 3) The system profile is identified as a non-server by the FADT. Link: https://gitlab.freedesktop.org/hadess/power-profiles-daemon/-/merge_requests/121 Reviewed-by: Gautham R. Shenoy <gautham.shenoy@xxxxxxx> Co-developed-by: Perry Yuan <perry.yuan@xxxxxxx> Signed-off-by: Perry Yuan <perry.yuan@xxxxxxx> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> --- drivers/cpufreq/Kconfig.x86 | 17 +++++++++ drivers/cpufreq/amd-pstate.c | 73 ++++++++++++++++++++++++------------ include/linux/amd-pstate.h | 4 +- 3 files changed, 68 insertions(+), 26 deletions(-) diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86 index 00476e94db90..438c9e75a04d 100644 --- a/drivers/cpufreq/Kconfig.x86 +++ b/drivers/cpufreq/Kconfig.x86 @@ -51,6 +51,23 @@ config X86_AMD_PSTATE If in doubt, say N. +config X86_AMD_PSTATE_DEFAULT_MODE + int "AMD Processor P-State default mode" + depends on X86_AMD_PSTATE + default 3 if X86_AMD_PSTATE + range 1 4 + help + Select the default mode the amd-pstate driver will use on + supported hardware. + The value set has the following meanings: + 1 -> Disabled + 2 -> Passive + 3 -> Active (EPP) + 4 -> Guided + + For details, take a look at: + <file:Documentation/admin-guide/pm/amd-pstate.rst>. + config X86_AMD_PSTATE_UT tristate "selftest for AMD Processor P-State driver" depends on X86 && ACPI_PROCESSOR diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index c9d296ebf81e..b400d1ee8e64 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -62,7 +62,7 @@ static struct cpufreq_driver *current_pstate_driver; static struct cpufreq_driver amd_pstate_driver; static struct cpufreq_driver amd_pstate_epp_driver; -static int cppc_state = AMD_PSTATE_DISABLE; +static int cppc_state = AMD_PSTATE_UNDEFINED; /* * AMD Energy Preference Performance (EPP) @@ -1363,6 +1363,25 @@ static struct cpufreq_driver amd_pstate_epp_driver = { .attr = amd_pstate_epp_attr, }; +static int __init amd_pstate_set_driver(int mode_idx) +{ + if (mode_idx >= AMD_PSTATE_DISABLE && mode_idx < AMD_PSTATE_MAX) { + cppc_state = mode_idx; + if (cppc_state == AMD_PSTATE_DISABLE) + pr_info("driver is explicitly disabled\n"); + + if (cppc_state == AMD_PSTATE_ACTIVE) + current_pstate_driver = &amd_pstate_epp_driver; + + if (cppc_state == AMD_PSTATE_PASSIVE || cppc_state == AMD_PSTATE_GUIDED) + current_pstate_driver = &amd_pstate_driver; + + return 0; + } + + return -EINVAL; +} + static int __init amd_pstate_init(void) { struct device *dev_root; @@ -1370,15 +1389,6 @@ static int __init amd_pstate_init(void) if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) return -ENODEV; - /* - * by default the pstate driver is disabled to load - * enable the amd_pstate passive mode driver explicitly - * with amd_pstate=passive or other modes in kernel command line - */ - if (cppc_state == AMD_PSTATE_DISABLE) { - pr_info("driver load is disabled, boot with specific mode to enable this\n"); - return -ENODEV; - } if (!acpi_cpc_valid()) { pr_warn_once("the _CPC object is not present in SBIOS or ACPI disabled\n"); @@ -1389,6 +1399,33 @@ static int __init amd_pstate_init(void) if (cpufreq_get_current_driver()) return -EEXIST; + switch (cppc_state) { + case AMD_PSTATE_UNDEFINED: + /* Disable on the following configs by default: + * 1. Undefined platforms + * 2. Server platforms + * 3. Shared memory designs + */ + if (acpi_pm_profile_undefined() || + acpi_pm_profile_server() || + !boot_cpu_has(X86_FEATURE_CPPC)) { + pr_info("driver load is disabled, boot with specific mode to enable this\n"); + return -ENODEV; + } + ret = amd_pstate_set_driver(CONFIG_X86_AMD_PSTATE_DEFAULT_MODE); + if (ret) + return ret; + break; + case AMD_PSTATE_DISABLE: + return -ENODEV; + case AMD_PSTATE_PASSIVE: + case AMD_PSTATE_ACTIVE: + case AMD_PSTATE_GUIDED: + break; + default: + return -EINVAL; + } + /* capability check */ if (boot_cpu_has(X86_FEATURE_CPPC)) { pr_debug("AMD CPPC MSR based functionality is supported\n"); @@ -1441,21 +1478,7 @@ static int __init amd_pstate_param(char *str) size = strlen(str); mode_idx = get_mode_idx_from_str(str, size); - if (mode_idx >= AMD_PSTATE_DISABLE && mode_idx < AMD_PSTATE_MAX) { - cppc_state = mode_idx; - if (cppc_state == AMD_PSTATE_DISABLE) - pr_info("driver is explicitly disabled\n"); - - if (cppc_state == AMD_PSTATE_ACTIVE) - current_pstate_driver = &amd_pstate_epp_driver; - - if (cppc_state == AMD_PSTATE_PASSIVE || cppc_state == AMD_PSTATE_GUIDED) - current_pstate_driver = &amd_pstate_driver; - - return 0; - } - - return -EINVAL; + return amd_pstate_set_driver(mode_idx); } early_param("amd_pstate", amd_pstate_param); diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h index c10ebf8c42e6..446394f84606 100644 --- a/include/linux/amd-pstate.h +++ b/include/linux/amd-pstate.h @@ -94,7 +94,8 @@ struct amd_cpudata { * enum amd_pstate_mode - driver working mode of amd pstate */ enum amd_pstate_mode { - AMD_PSTATE_DISABLE = 0, + AMD_PSTATE_UNDEFINED = 0, + AMD_PSTATE_DISABLE, AMD_PSTATE_PASSIVE, AMD_PSTATE_ACTIVE, AMD_PSTATE_GUIDED, @@ -102,6 +103,7 @@ enum amd_pstate_mode { }; static const char * const amd_pstate_mode_string[] = { + [AMD_PSTATE_UNDEFINED] = "undefined", [AMD_PSTATE_DISABLE] = "disable", [AMD_PSTATE_PASSIVE] = "passive", [AMD_PSTATE_ACTIVE] = "active", -- 2.34.1