Merge branch 'acpi-cppc' into linux-next * acpi-cppc: cpufreq: CPPC: Add sysfs documentation for perf_limited ACPI: CPPC: add APIs and sysfs interface for perf_limited cpufreq: cppc: Update MIN_PERF/MAX_PERF in target callbacks cpufreq: CPPC: Update cached perf_ctrls on sysfs write ACPI: CPPC: Extend cppc_set_epp_perf() for FFH/SystemMemory ACPI: CPPC: Warn on missing mandatory DESIRED_PERF register ACPI: CPPC: Add cppc_get_perf() API to read performance controls
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 3a05604..82d10d5 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -327,6 +327,24 @@ This file is only present if the cppc-cpufreq driver is in use. +What: /sys/devices/system/cpu/cpuX/cpufreq/perf_limited +Date: February 2026 +Contact: linux-pm@vger.kernel.org +Description: Performance Limited + + Read to check if platform throttling (thermal/power/current + limits) caused delivered performance to fall below the + requested level. A non-zero value indicates throttling occurred. + + Write the bitmask of bits to clear: + + - 0x1 = clear bit 0 (desired performance excursion) + - 0x2 = clear bit 1 (minimum performance excursion) + - 0x3 = clear both bits + + The platform sets these bits; OSPM can only clear them. + + This file is only present if the cppc-cpufreq driver is in use. What: /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1} Date: August 2008
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index f0e513e..53a6ffd 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c
@@ -854,6 +854,16 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) per_cpu(cpu_pcc_subspace_idx, pr->id) = pcc_subspace_id; /* + * In CPPC v1, DESIRED_PERF is mandatory. In CPPC v2, it is optional + * only when AUTO_SEL_ENABLE is supported. + */ + if (!CPC_SUPPORTED(&cpc_ptr->cpc_regs[DESIRED_PERF]) && + (!osc_sb_cppc2_support_acked || + !CPC_SUPPORTED(&cpc_ptr->cpc_regs[AUTO_SEL_ENABLE]))) + pr_warn("Desired perf. register is mandatory if CPPC v2 is not supported " + "or autonomous selection is disabled\n"); + + /* * Initialize the remaining cpc_regs as unsupported. * Example: In case FW exposes CPPC v2, the below loop will initialize * LOWEST_FREQ and NOMINAL_FREQ regs as unsupported @@ -1561,6 +1571,8 @@ int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable) struct cpc_register_resource *auto_sel_reg; struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); struct cppc_pcc_data *pcc_ss_data = NULL; + bool autosel_ffh_sysmem; + bool epp_ffh_sysmem; int ret; if (!cpc_desc) { @@ -1571,6 +1583,11 @@ int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable) auto_sel_reg = &cpc_desc->cpc_regs[AUTO_SEL_ENABLE]; epp_set_reg = &cpc_desc->cpc_regs[ENERGY_PERF]; + epp_ffh_sysmem = CPC_SUPPORTED(epp_set_reg) && + (CPC_IN_FFH(epp_set_reg) || CPC_IN_SYSTEM_MEMORY(epp_set_reg)); + autosel_ffh_sysmem = CPC_SUPPORTED(auto_sel_reg) && + (CPC_IN_FFH(auto_sel_reg) || CPC_IN_SYSTEM_MEMORY(auto_sel_reg)); + if (CPC_IN_PCC(epp_set_reg) || CPC_IN_PCC(auto_sel_reg)) { if (pcc_ss_id < 0) { pr_debug("Invalid pcc_ss_id for CPU:%d\n", cpu); @@ -1596,11 +1613,22 @@ int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable) ret = send_pcc_cmd(pcc_ss_id, CMD_WRITE); up_write(&pcc_ss_data->pcc_lock); } else if (osc_cpc_flexible_adr_space_confirmed && - CPC_SUPPORTED(epp_set_reg) && CPC_IN_FFH(epp_set_reg)) { - ret = cpc_write(cpu, epp_set_reg, perf_ctrls->energy_perf); + (epp_ffh_sysmem || autosel_ffh_sysmem)) { + if (autosel_ffh_sysmem) { + ret = cpc_write(cpu, auto_sel_reg, enable); + if (ret) + return ret; + } + + if (epp_ffh_sysmem) { + ret = cpc_write(cpu, epp_set_reg, + perf_ctrls->energy_perf); + if (ret) + return ret; + } } else { ret = -ENOTSUPP; - pr_debug("_CPC in PCC and _CPC in FFH are not supported\n"); + pr_debug("_CPC in PCC/FFH/SystemMemory are not supported\n"); } return ret; @@ -1739,6 +1767,86 @@ int cppc_set_enable(int cpu, bool enable) EXPORT_SYMBOL_GPL(cppc_set_enable); /** + * cppc_get_perf - Get a CPU's performance controls. + * @cpu: CPU for which to get performance controls. + * @perf_ctrls: ptr to cppc_perf_ctrls. See cppc_acpi.h + * + * Return: 0 for success with perf_ctrls, -ERRNO otherwise. + */ +int cppc_get_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls) +{ + struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); + struct cpc_register_resource *desired_perf_reg, + *min_perf_reg, *max_perf_reg, + *energy_perf_reg, *auto_sel_reg; + u64 desired_perf = 0, min = 0, max = 0, energy_perf = 0, auto_sel = 0; + int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); + struct cppc_pcc_data *pcc_ss_data = NULL; + int ret = 0, regs_in_pcc = 0; + + if (!cpc_desc) { + pr_debug("No CPC descriptor for CPU:%d\n", cpu); + return -ENODEV; + } + + if (!perf_ctrls) { + pr_debug("Invalid perf_ctrls pointer\n"); + return -EINVAL; + } + + desired_perf_reg = &cpc_desc->cpc_regs[DESIRED_PERF]; + min_perf_reg = &cpc_desc->cpc_regs[MIN_PERF]; + max_perf_reg = &cpc_desc->cpc_regs[MAX_PERF]; + energy_perf_reg = &cpc_desc->cpc_regs[ENERGY_PERF]; + auto_sel_reg = &cpc_desc->cpc_regs[AUTO_SEL_ENABLE]; + + /* Are any of the regs PCC ?*/ + if (CPC_IN_PCC(desired_perf_reg) || CPC_IN_PCC(min_perf_reg) || + CPC_IN_PCC(max_perf_reg) || CPC_IN_PCC(energy_perf_reg) || + CPC_IN_PCC(auto_sel_reg)) { + if (pcc_ss_id < 0) { + pr_debug("Invalid pcc_ss_id for CPU:%d\n", cpu); + return -ENODEV; + } + pcc_ss_data = pcc_data[pcc_ss_id]; + regs_in_pcc = 1; + down_write(&pcc_ss_data->pcc_lock); + /* Ring doorbell once to update PCC subspace */ + if (send_pcc_cmd(pcc_ss_id, CMD_READ) < 0) { + ret = -EIO; + goto out_err; + } + } + + /* Read optional elements if present */ + if (CPC_SUPPORTED(max_perf_reg)) + cpc_read(cpu, max_perf_reg, &max); + perf_ctrls->max_perf = max; + + if (CPC_SUPPORTED(min_perf_reg)) + cpc_read(cpu, min_perf_reg, &min); + perf_ctrls->min_perf = min; + + if (CPC_SUPPORTED(desired_perf_reg)) + cpc_read(cpu, desired_perf_reg, &desired_perf); + perf_ctrls->desired_perf = desired_perf; + + if (CPC_SUPPORTED(energy_perf_reg)) + cpc_read(cpu, energy_perf_reg, &energy_perf); + perf_ctrls->energy_perf = energy_perf; + + if (CPC_SUPPORTED(auto_sel_reg)) + cpc_read(cpu, auto_sel_reg, &auto_sel); + perf_ctrls->auto_sel = (bool)auto_sel; + +out_err: + if (regs_in_pcc) + up_write(&pcc_ss_data->pcc_lock); + return ret; +} +EXPORT_SYMBOL_GPL(cppc_get_perf); + +/** * cppc_set_perf - Set a CPU's performance controls. * @cpu: CPU for which to set performance controls. * @perf_ctrls: ptr to cppc_perf_ctrls. See cppc_acpi.h @@ -1871,6 +1979,62 @@ int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls) EXPORT_SYMBOL_GPL(cppc_set_perf); /** + * cppc_get_perf_limited - Get the Performance Limited register value. + * @cpu: CPU from which to get Performance Limited register. + * @perf_limited: Pointer to store the Performance Limited value. + * + * The returned value contains sticky status bits indicating platform-imposed + * performance limitations. + * + * Return: 0 for success, -EIO on failure, -EOPNOTSUPP if not supported. + */ +int cppc_get_perf_limited(int cpu, u64 *perf_limited) +{ + return cppc_get_reg_val(cpu, PERF_LIMITED, perf_limited); +} +EXPORT_SYMBOL_GPL(cppc_get_perf_limited); + +/** + * cppc_set_perf_limited() - Clear bits in the Performance Limited register. + * @cpu: CPU on which to write register. + * @bits_to_clear: Bitmask of bits to clear in the perf_limited register. + * + * The Performance Limited register contains two sticky bits set by platform: + * - Bit 0 (Desired_Excursion): Set when delivered performance is constrained + * below desired performance. Not used when Autonomous Selection is enabled. + * - Bit 1 (Minimum_Excursion): Set when delivered performance is constrained + * below minimum performance. + * + * These bits are sticky and remain set until OSPM explicitly clears them. + * This function only allows clearing bits (the platform sets them). + * + * Return: 0 for success, -EINVAL for invalid bits, -EIO on register + * access failure, -EOPNOTSUPP if not supported. + */ +int cppc_set_perf_limited(int cpu, u64 bits_to_clear) +{ + u64 current_val, new_val; + int ret; + + /* Only bits 0 and 1 are valid */ + if (bits_to_clear & ~CPPC_PERF_LIMITED_MASK) + return -EINVAL; + + if (!bits_to_clear) + return 0; + + ret = cppc_get_perf_limited(cpu, ¤t_val); + if (ret) + return ret; + + /* Clear the specified bits */ + new_val = current_val & ~bits_to_clear; + + return cppc_set_reg_val(cpu, PERF_LIMITED, new_val); +} +EXPORT_SYMBOL_GPL(cppc_set_perf_limited); + +/** * cppc_get_transition_latency - returns frequency transition latency in ns * @cpu_num: CPU number for per_cpu(). *
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 011f35c..94d489a 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -287,6 +287,21 @@ static inline void cppc_freq_invariance_exit(void) } #endif /* CONFIG_ACPI_CPPC_CPUFREQ_FIE */ +static void cppc_cpufreq_update_perf_limits(struct cppc_cpudata *cpu_data, + struct cpufreq_policy *policy) +{ + struct cppc_perf_caps *caps = &cpu_data->perf_caps; + u32 min_perf, max_perf; + + min_perf = cppc_khz_to_perf(caps, policy->min); + max_perf = cppc_khz_to_perf(caps, policy->max); + + cpu_data->perf_ctrls.min_perf = + clamp_t(u32, min_perf, caps->lowest_perf, caps->highest_perf); + cpu_data->perf_ctrls.max_perf = + clamp_t(u32, max_perf, caps->lowest_perf, caps->highest_perf); +} + static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) @@ -298,6 +313,8 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, cpu_data->perf_ctrls.desired_perf = cppc_khz_to_perf(&cpu_data->perf_caps, target_freq); + cppc_cpufreq_update_perf_limits(cpu_data, policy); + freqs.old = policy->cur; freqs.new = target_freq; @@ -322,8 +339,9 @@ static unsigned int cppc_cpufreq_fast_switch(struct cpufreq_policy *policy, desired_perf = cppc_khz_to_perf(&cpu_data->perf_caps, target_freq); cpu_data->perf_ctrls.desired_perf = desired_perf; - ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); + cppc_cpufreq_update_perf_limits(cpu_data, policy); + ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); if (ret) { pr_debug("Failed to set target on CPU:%d. ret:%d\n", cpu, ret); @@ -594,6 +612,12 @@ static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu) goto free_mask; } + ret = cppc_get_perf(cpu, &cpu_data->perf_ctrls); + if (ret) { + pr_debug("Err reading CPU%d perf ctrls: ret:%d\n", cpu, ret); + goto free_mask; + } + return cpu_data; free_mask: @@ -849,6 +873,7 @@ static ssize_t show_auto_select(struct cpufreq_policy *policy, char *buf) static ssize_t store_auto_select(struct cpufreq_policy *policy, const char *buf, size_t count) { + struct cppc_cpudata *cpu_data = policy->driver_data; bool val; int ret; @@ -860,6 +885,29 @@ static ssize_t store_auto_select(struct cpufreq_policy *policy, if (ret) return ret; + cpu_data->perf_ctrls.auto_sel = val; + + if (val) { + u32 old_min_perf = cpu_data->perf_ctrls.min_perf; + u32 old_max_perf = cpu_data->perf_ctrls.max_perf; + + /* + * When enabling autonomous selection, program MIN_PERF and + * MAX_PERF from current policy limits so that the platform + * uses the correct performance bounds immediately. + */ + cppc_cpufreq_update_perf_limits(cpu_data, policy); + + ret = cppc_set_perf(policy->cpu, &cpu_data->perf_ctrls); + if (ret) { + cpu_data->perf_ctrls.min_perf = old_min_perf; + cpu_data->perf_ctrls.max_perf = old_max_perf; + cppc_set_auto_sel(policy->cpu, false); + cpu_data->perf_ctrls.auto_sel = false; + return ret; + } + } + return count; } @@ -910,19 +958,48 @@ static ssize_t store_##_name(struct cpufreq_policy *policy, \ CPPC_CPUFREQ_ATTR_RW_U64(auto_act_window, cppc_get_auto_act_window, cppc_set_auto_act_window) -CPPC_CPUFREQ_ATTR_RW_U64(energy_performance_preference_val, - cppc_get_epp_perf, cppc_set_epp) +static ssize_t +show_energy_performance_preference_val(struct cpufreq_policy *policy, char *buf) +{ + return cppc_cpufreq_sysfs_show_u64(policy->cpu, cppc_get_epp_perf, buf); +} + +static ssize_t +store_energy_performance_preference_val(struct cpufreq_policy *policy, + const char *buf, size_t count) +{ + struct cppc_cpudata *cpu_data = policy->driver_data; + u64 val; + int ret; + + ret = kstrtou64(buf, 0, &val); + if (ret) + return ret; + + ret = cppc_set_epp(policy->cpu, val); + if (ret) + return ret; + + cpu_data->perf_ctrls.energy_perf = val; + + return count; +} + +CPPC_CPUFREQ_ATTR_RW_U64(perf_limited, cppc_get_perf_limited, + cppc_set_perf_limited) cpufreq_freq_attr_ro(freqdomain_cpus); cpufreq_freq_attr_rw(auto_select); cpufreq_freq_attr_rw(auto_act_window); cpufreq_freq_attr_rw(energy_performance_preference_val); +cpufreq_freq_attr_rw(perf_limited); static struct freq_attr *cppc_cpufreq_attr[] = { &freqdomain_cpus, &auto_select, &auto_act_window, &energy_performance_preference_val, + &perf_limited, NULL, };
diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h index 4d644f03..f7afa20 100644 --- a/include/acpi/cppc_acpi.h +++ b/include/acpi/cppc_acpi.h
@@ -42,6 +42,11 @@ #define CPPC_EPP_PERFORMANCE_PREF 0x00 #define CPPC_EPP_ENERGY_EFFICIENCY_PREF 0xFF +#define CPPC_PERF_LIMITED_DESIRED_EXCURSION BIT(0) +#define CPPC_PERF_LIMITED_MINIMUM_EXCURSION BIT(1) +#define CPPC_PERF_LIMITED_MASK (CPPC_PERF_LIMITED_DESIRED_EXCURSION | \ + CPPC_PERF_LIMITED_MINIMUM_EXCURSION) + /* Each register has the folowing format. */ struct cpc_reg { u8 descriptor; @@ -151,6 +156,7 @@ 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_get_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls); extern int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls); extern int cppc_set_enable(int cpu, bool enable); extern int cppc_get_perf_caps(int cpu, struct cppc_perf_caps *caps); @@ -173,6 +179,8 @@ 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_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); extern int amd_get_boost_ratio_numerator(unsigned int cpu, u64 *numerator); extern int amd_detect_prefcore(bool *detected); @@ -193,6 +201,10 @@ static inline int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ { return -EOPNOTSUPP; } +static inline int cppc_get_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls) +{ + return -EOPNOTSUPP; +} static inline int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls) { return -EOPNOTSUPP; @@ -265,6 +277,14 @@ static inline int cppc_set_auto_sel(int cpu, bool enable) { return -EOPNOTSUPP; } +static inline int cppc_get_perf_limited(int cpu, u64 *perf_limited) +{ + return -EOPNOTSUPP; +} +static inline int cppc_set_perf_limited(int cpu, u64 bits_to_clear) +{ + return -EOPNOTSUPP; +} static inline int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf) { return -ENODEV;