From 4f460bff7b6ac53d7d8509501a9fba7292a4a11a Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Tue, 25 Jun 2024 23:27:30 -0500 Subject: [PATCH 1/4] cpufreq: acpi: move MSR_K7_HWCR_CPB_DIS_BIT into msr-index.h There are some other drivers also need to use the MSR_K7_HWCR_CPB_DIS_BIT for CPB control bit, so it makes sense to move the definition to a common header file to allow other driver to use it. No intentional functional impact. Suggested-by: Gautham Ranjal Shenoy Signed-off-by: Perry Yuan Acked-by: Rafael J. Wysocki Acked-by: Huang Rui Link: https://lore.kernel.org/r/78b6c75e6cffddce3e950dd543af6ae9f8eeccc3.1718988436.git.perry.yuan@amd.com Link: https://lore.kernel.org/r/20240626042733.3747-2-mario.limonciello@amd.com Signed-off-by: Mario Limonciello --- arch/x86/include/asm/msr-index.h | 2 ++ drivers/cpufreq/acpi-cpufreq.c | 2 -- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index e022e6eb766c6..384739d592af2 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -781,6 +781,8 @@ #define MSR_K7_HWCR_IRPERF_EN BIT_ULL(MSR_K7_HWCR_IRPERF_EN_BIT) #define MSR_K7_FID_VID_CTL 0xc0010041 #define MSR_K7_FID_VID_STATUS 0xc0010042 +#define MSR_K7_HWCR_CPB_DIS_BIT 25 +#define MSR_K7_HWCR_CPB_DIS BIT_ULL(MSR_K7_HWCR_CPB_DIS_BIT) /* K6 MSRs */ #define MSR_K6_WHCR 0xc0000082 diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c index 37f1cdf46d291..2fc82831bddd5 100644 --- a/drivers/cpufreq/acpi-cpufreq.c +++ b/drivers/cpufreq/acpi-cpufreq.c @@ -50,8 +50,6 @@ enum { #define AMD_MSR_RANGE (0x7) #define HYGON_MSR_RANGE (0x7) -#define MSR_K7_HWCR_CPB_DIS (1ULL << 25) - struct acpi_cpufreq_data { unsigned int resume; unsigned int cpu_feature; From c8c68c38b56f4036771ebe2f8d664a2e98728318 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Tue, 25 Jun 2024 23:27:31 -0500 Subject: [PATCH 2/4] cpufreq: amd-pstate: initialize core precision boost state The "Core Performance Boost (CPB) feature, when enabled in the BIOS, allows the OS to control the highest performance for each individual core. The active, passive and the guided modes of the amd-pstate driver do support controlling the core frequency boost when this BIOS feature is enabled. Additionally, the amd-pstate driver provides a sysfs interface allowing the user to activate/deactivate this core performance boost feature at runtime. Add support for the set_boost callback in the active mode driver to enable boost control via the cpufreq core. This ensures a consistent boost control interface across all pstate modes, including passive mode, guided mode, and active mode. With this addition, all three pstate modes can support the same boost control interface with unique interface and global CPB control. Each CPU also supports individual boost control, allowing global CPB to change all cores' boost states simultaneously. Specific CPUs can update their boost states separately, ensuring all cores' boost states are synchronized. Cc: Oleksandr Natalenko Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217931 Signed-off-by: Perry Yuan Co-developed-by: Mario Limonciello Reviewed-by: Gautham R. Shenoy Link: https://lore.kernel.org/r/20240626042733.3747-3-mario.limonciello@amd.com Signed-off-by: Mario Limonciello --- drivers/cpufreq/amd-pstate.c | 117 ++++++++++++++++++++++++++++------- drivers/cpufreq/amd-pstate.h | 1 + 2 files changed, 96 insertions(+), 22 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index afcf398574f61..db4fbd8d1e065 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -679,43 +679,105 @@ static void amd_pstate_adjust_perf(unsigned int cpu, cpufreq_cpu_put(policy); } -static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state) +static int amd_pstate_cpu_boost_update(struct cpufreq_policy *policy, bool on) { struct amd_cpudata *cpudata = policy->driver_data; + struct cppc_perf_ctrls perf_ctrls; + u32 highest_perf, nominal_perf, nominal_freq, max_freq; int ret; - if (!cpudata->boost_supported) { - pr_err("Boost mode is not supported by this processor or SBIOS\n"); - return -EINVAL; + highest_perf = READ_ONCE(cpudata->highest_perf); + nominal_perf = READ_ONCE(cpudata->nominal_perf); + nominal_freq = READ_ONCE(cpudata->nominal_freq); + max_freq = READ_ONCE(cpudata->max_freq); + + if (boot_cpu_has(X86_FEATURE_CPPC)) { + u64 value = READ_ONCE(cpudata->cppc_req_cached); + + value &= ~GENMASK_ULL(7, 0); + value |= on ? highest_perf : nominal_perf; + WRITE_ONCE(cpudata->cppc_req_cached, value); + + wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value); + } else { + perf_ctrls.max_perf = on ? highest_perf : nominal_perf; + ret = cppc_set_perf(cpudata->cpu, &perf_ctrls); + if (ret) { + cpufreq_cpu_release(policy); + pr_debug("Failed to set max perf on CPU:%d. ret:%d\n", + cpudata->cpu, ret); + return ret; + } } - if (state) - policy->cpuinfo.max_freq = cpudata->max_freq; - else - policy->cpuinfo.max_freq = cpudata->nominal_freq * 1000; + if (on) + policy->cpuinfo.max_freq = max_freq; + else if (policy->cpuinfo.max_freq > nominal_freq * 1000) + policy->cpuinfo.max_freq = nominal_freq * 1000; policy->max = policy->cpuinfo.max_freq; - ret = freq_qos_update_request(&cpudata->req[1], - policy->cpuinfo.max_freq); - if (ret < 0) - return ret; + if (cppc_state == AMD_PSTATE_PASSIVE) { + ret = freq_qos_update_request(&cpudata->req[1], policy->cpuinfo.max_freq); + if (ret < 0) + pr_debug("Failed to update freq constraint: CPU%d\n", cpudata->cpu); + } - return 0; + return ret < 0 ? ret : 0; } -static void amd_pstate_boost_init(struct amd_cpudata *cpudata) +static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state) { - u32 highest_perf, nominal_perf; + struct amd_cpudata *cpudata = policy->driver_data; + int ret; - highest_perf = READ_ONCE(cpudata->highest_perf); - nominal_perf = READ_ONCE(cpudata->nominal_perf); + if (!cpudata->boost_supported) { + pr_err("Boost mode is not supported by this processor or SBIOS\n"); + return -EOPNOTSUPP; + } + mutex_lock(&amd_pstate_driver_lock); + ret = amd_pstate_cpu_boost_update(policy, state); + WRITE_ONCE(cpudata->boost_state, !ret ? state : false); + policy->boost_enabled = !ret ? state : false; + refresh_frequency_limits(policy); + mutex_unlock(&amd_pstate_driver_lock); - if (highest_perf <= nominal_perf) - return; + return ret; +} - cpudata->boost_supported = true; +static int amd_pstate_init_boost_support(struct amd_cpudata *cpudata) +{ + u64 boost_val; + int ret = -1; + + /* + * If platform has no CPB support or disable it, initialize current driver + * boost_enabled state to be false, it is not an error for cpufreq core to handle. + */ + if (!cpu_feature_enabled(X86_FEATURE_CPB)) { + pr_debug_once("Boost CPB capabilities not present in the processor\n"); + ret = 0; + goto exit_err; + } + + /* at least one CPU supports CPB, even if others fail later on to set up */ current_pstate_driver->boost_enabled = true; + + ret = rdmsrl_on_cpu(cpudata->cpu, MSR_K7_HWCR, &boost_val); + if (ret) { + pr_err_once("failed to read initial CPU boost state!\n"); + ret = -EIO; + goto exit_err; + } + + if (!(boost_val & MSR_K7_HWCR_CPB_DIS)) + cpudata->boost_supported = true; + + return 0; + +exit_err: + cpudata->boost_supported = false; + return ret; } static void amd_perf_ctl_reset(unsigned int cpu) @@ -968,6 +1030,10 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) if (ret) goto free_cpudata1; + ret = amd_pstate_init_boost_support(cpudata); + if (ret) + goto free_cpudata1; + min_freq = READ_ONCE(cpudata->min_freq); max_freq = READ_ONCE(cpudata->max_freq); @@ -980,6 +1046,8 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) policy->cpuinfo.min_freq = min_freq; policy->cpuinfo.max_freq = max_freq; + policy->boost_enabled = READ_ONCE(cpudata->boost_supported); + /* It will be updated by governor */ policy->cur = policy->cpuinfo.min_freq; @@ -1005,7 +1073,6 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) policy->driver_data = cpudata; - amd_pstate_boost_init(cpudata); if (!current_pstate_driver->adjust_perf) current_pstate_driver->adjust_perf = amd_pstate_adjust_perf; @@ -1420,6 +1487,10 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) if (ret) goto free_cpudata1; + ret = amd_pstate_init_boost_support(cpudata); + if (ret) + goto free_cpudata1; + min_freq = READ_ONCE(cpudata->min_freq); max_freq = READ_ONCE(cpudata->max_freq); @@ -1435,6 +1506,8 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) policy->min = policy->cpuinfo.min_freq; policy->max = policy->cpuinfo.max_freq; + policy->boost_enabled = READ_ONCE(cpudata->boost_supported); + /* * Set the policy to provide a valid fallback value in case * the default cpufreq governor is neither powersave nor performance. @@ -1456,7 +1529,6 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) return ret; WRITE_ONCE(cpudata->cppc_cap1_cached, value); } - amd_pstate_boost_init(cpudata); return 0; @@ -1718,6 +1790,7 @@ static struct cpufreq_driver amd_pstate_epp_driver = { .suspend = amd_pstate_epp_suspend, .resume = amd_pstate_epp_resume, .update_limits = amd_pstate_update_limits, + .set_boost = amd_pstate_set_boost, .name = "amd-pstate-epp", .attr = amd_pstate_epp_attr, }; diff --git a/drivers/cpufreq/amd-pstate.h b/drivers/cpufreq/amd-pstate.h index f80b33fa5d43a..cc8bb2bc325aa 100644 --- a/drivers/cpufreq/amd-pstate.h +++ b/drivers/cpufreq/amd-pstate.h @@ -100,6 +100,7 @@ struct amd_cpudata { u64 cppc_cap1_cached; bool suspended; s16 epp_default; + bool boost_state; }; #endif /* _LINUX_AMD_PSTATE_H */ From 89ac482d5105b0c6710775bab1aa7d3d0730c642 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Tue, 25 Jun 2024 23:27:32 -0500 Subject: [PATCH 3/4] cpufreq: amd-pstate: Cap the CPPC.max_perf to nominal_perf if CPB is off When Core Performance Boost is disabled by the user, the CPPC_REQ.max_perf should not exceed the nominal_perf since by definition the frequencies between nominal_perf and the highest_perf are in the boost range. Fix this in amd_pstate_update() Acked-by: Huang Rui Reviewed-by: Mario Limonciello Reviewed-by: Gautham R. Shenoy Signed-off-by: Perry Yuan Link: https://lore.kernel.org/r/66f55232be01092c423f0523f68b82b80c293943.1718988436.git.perry.yuan@amd.com Link: https://lore.kernel.org/r/20240626042733.3747-4-mario.limonciello@amd.com Signed-off-by: Mario Limonciello --- drivers/cpufreq/amd-pstate.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index db4fbd8d1e065..80eaa58f1405e 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -514,6 +514,7 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf, unsigned long max_freq; struct cpufreq_policy *policy = cpufreq_cpu_get(cpudata->cpu); u64 prev = READ_ONCE(cpudata->cppc_req_cached); + u32 nominal_perf = READ_ONCE(cpudata->nominal_perf); u64 value = prev; min_perf = clamp_t(unsigned long, min_perf, cpudata->min_limit_perf, @@ -536,6 +537,10 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf, value &= ~AMD_CPPC_DES_PERF(~0L); value |= AMD_CPPC_DES_PERF(des_perf); + /* limit the max perf when core performance boost feature is disabled */ + if (!cpudata->boost_supported) + max_perf = min_t(unsigned long, nominal_perf, max_perf); + value &= ~AMD_CPPC_MAX_PERF(~0L); value |= AMD_CPPC_MAX_PERF(max_perf); From 6d588891a90c5a946aaac11a93d06edd89ed9054 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Tue, 25 Jun 2024 23:27:33 -0500 Subject: [PATCH 4/4] Documentation: cpufreq: amd-pstate: update doc for Per CPU boost control method Updates the documentation in `amd-pstate.rst` to include information about the per CPU boost control feature. Users can now enable or disable the Core Performance Boost (CPB) feature on individual CPUs using the `boost` sysfs attribute. Reviewed-by: Gautham R. Shenoy Signed-off-by: Perry Yuan Co-developed-by: Mario Limonciello Link: https://lore.kernel.org/r/20240626042733.3747-5-mario.limonciello@amd.com Signed-off-by: Mario Limonciello --- Documentation/admin-guide/pm/amd-pstate.rst | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst index f5ee81419a935..d0324d44f5482 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -281,6 +281,22 @@ integer values defined between 0 to 255 when EPP feature is enabled by platform firmware, if EPP feature is disabled, driver will ignore the written value This attribute is read-write. +``boost`` +The `boost` sysfs attribute provides control over the CPU core +performance boost, allowing users to manage the maximum frequency limitation +of the CPU. This attribute can be used to enable or disable the boost feature +on individual CPUs. + +When the boost feature is enabled, the CPU can dynamically increase its frequency +beyond the base frequency, providing enhanced performance for demanding workloads. +On the other hand, disabling the boost feature restricts the CPU to operate at the +base frequency, which may be desirable in certain scenarios to prioritize power +efficiency or manage temperature. + +To manipulate the `boost` attribute, users can write a value of `0` to disable the +boost or `1` to enable it, for the respective CPU using the sysfs path +`/sys/devices/system/cpu/cpuX/cpufreq/boost`, where `X` represents the CPU number. + Other performance and frequency values can be read back from ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`.