diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 61dcd7b89b26a..7955cfc91c319 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -106,6 +106,8 @@ static unsigned int epp_values[] = { [EPP_INDEX_POWERSAVE] = AMD_CPPC_EPP_POWERSAVE, }; +typedef int (*cppc_mode_transition_fn)(int); + static inline int get_mode_idx_from_str(const char *str, size_t size) { int i; @@ -838,6 +840,98 @@ static ssize_t show_energy_performance_preference( return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]); } +static void amd_pstate_driver_cleanup(void) +{ + amd_pstate_enable(false); + cppc_state = AMD_PSTATE_DISABLE; + current_pstate_driver = NULL; +} + +static int amd_pstate_register_driver(int mode) +{ + int ret; + + if (mode == AMD_PSTATE_PASSIVE || mode == AMD_PSTATE_GUIDED) + current_pstate_driver = &amd_pstate_driver; + else if (mode == AMD_PSTATE_ACTIVE) + current_pstate_driver = &amd_pstate_epp_driver; + else + return -EINVAL; + + cppc_state = mode; + ret = cpufreq_register_driver(current_pstate_driver); + if (ret) { + amd_pstate_driver_cleanup(); + return ret; + } + return 0; +} + +static int amd_pstate_unregister_driver(int dummy) +{ + cpufreq_unregister_driver(current_pstate_driver); + amd_pstate_driver_cleanup(); + return 0; +} + +static int amd_pstate_change_mode_without_dvr_change(int mode) +{ + int cpu = 0; + + cppc_state = mode; + + if (boot_cpu_has(X86_FEATURE_CPPC) || cppc_state == AMD_PSTATE_ACTIVE) + return 0; + + for_each_present_cpu(cpu) { + cppc_set_auto_sel(cpu, (cppc_state == AMD_PSTATE_PASSIVE) ? 0 : 1); + } + + return 0; +} + +static int amd_pstate_change_driver_mode(int mode) +{ + int ret; + + ret = amd_pstate_unregister_driver(0); + if (ret) + return ret; + + ret = amd_pstate_register_driver(mode); + if (ret) + return ret; + + return 0; +} + +cppc_mode_transition_fn mode_state_machine[AMD_PSTATE_MAX][AMD_PSTATE_MAX] = { + [AMD_PSTATE_DISABLE] = { + [AMD_PSTATE_DISABLE] = NULL, + [AMD_PSTATE_PASSIVE] = amd_pstate_register_driver, + [AMD_PSTATE_ACTIVE] = amd_pstate_register_driver, + [AMD_PSTATE_GUIDED] = amd_pstate_register_driver, + }, + [AMD_PSTATE_PASSIVE] = { + [AMD_PSTATE_DISABLE] = amd_pstate_unregister_driver, + [AMD_PSTATE_PASSIVE] = NULL, + [AMD_PSTATE_ACTIVE] = amd_pstate_change_driver_mode, + [AMD_PSTATE_GUIDED] = amd_pstate_change_mode_without_dvr_change, + }, + [AMD_PSTATE_ACTIVE] = { + [AMD_PSTATE_DISABLE] = amd_pstate_unregister_driver, + [AMD_PSTATE_PASSIVE] = amd_pstate_change_driver_mode, + [AMD_PSTATE_ACTIVE] = NULL, + [AMD_PSTATE_GUIDED] = amd_pstate_change_driver_mode, + }, + [AMD_PSTATE_GUIDED] = { + [AMD_PSTATE_DISABLE] = amd_pstate_unregister_driver, + [AMD_PSTATE_PASSIVE] = amd_pstate_change_mode_without_dvr_change, + [AMD_PSTATE_ACTIVE] = amd_pstate_change_driver_mode, + [AMD_PSTATE_GUIDED] = NULL, + }, +}; + static ssize_t amd_pstate_show_status(char *buf) { if (!current_pstate_driver) @@ -846,57 +940,22 @@ static ssize_t amd_pstate_show_status(char *buf) return sysfs_emit(buf, "%s\n", amd_pstate_mode_string[cppc_state]); } -static void amd_pstate_driver_cleanup(void) -{ - current_pstate_driver = NULL; -} - static int amd_pstate_update_status(const char *buf, size_t size) { - int ret = 0; int mode_idx; - if (size > 7 || size < 6) + if (size > strlen("passive") || size < strlen("active")) return -EINVAL; - mode_idx = get_mode_idx_from_str(buf, size); - switch(mode_idx) { - case AMD_PSTATE_DISABLE: - if (!current_pstate_driver) - return -EINVAL; - if (cppc_state == AMD_PSTATE_ACTIVE) - return -EBUSY; - cpufreq_unregister_driver(current_pstate_driver); - amd_pstate_driver_cleanup(); - break; - case AMD_PSTATE_PASSIVE: - if (current_pstate_driver) { - if (current_pstate_driver == &amd_pstate_driver) - return 0; - cpufreq_unregister_driver(current_pstate_driver); - cppc_state = AMD_PSTATE_PASSIVE; - current_pstate_driver = &amd_pstate_driver; - } + mode_idx = get_mode_idx_from_str(buf, size); - ret = cpufreq_register_driver(current_pstate_driver); - break; - case AMD_PSTATE_ACTIVE: - if (current_pstate_driver) { - if (current_pstate_driver == &amd_pstate_epp_driver) - return 0; - cpufreq_unregister_driver(current_pstate_driver); - current_pstate_driver = &amd_pstate_epp_driver; - cppc_state = AMD_PSTATE_ACTIVE; - } + if (mode_idx < 0 || mode_idx >= AMD_PSTATE_MAX) + return -EINVAL; - ret = cpufreq_register_driver(current_pstate_driver); - break; - default: - ret = -EINVAL; - break; - } + if (mode_state_machine[cppc_state][mode_idx]) + return mode_state_machine[cppc_state][mode_idx](mode_idx); - return ret; + return 0; } static ssize_t show_status(struct kobject *kobj,