From b37ef7210e51b1e996ca03b03227d93f7470784b Mon Sep 17 00:00:00 2001 From: "Gautham R. Shenoy" Date: Thu, 25 Apr 2024 16:07:51 +0800 Subject: [PATCH 01/11] cpufreq: amd-pstate: Document *_limit_* fields in struct amd_cpudata The four fields of struct cpudata namely min_limit_perf, max_limit_perf, min_limit_freq, max_limit_freq introduced in the commit febab20caeba("cpufreq/amd-pstate: Fix scaling_min_freq and scaling_max_freq update") are currently undocumented Add comments describing these fields Acked-by: Huang Rui Fixes: febab20caeba("cpufreq/amd-pstate: Fix scaling_min_freq and scaling_max_freq update") Reviewed-by: Li Meng Tested-by: Dhananjay Ugwekar Signed-off-by: Gautham R. Shenoy Signed-off-by: Perry Yuan Signed-off-by: Rafael J. Wysocki --- include/linux/amd-pstate.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h index d21838835abda..83fb3fc647fce 100644 --- a/include/linux/amd-pstate.h +++ b/include/linux/amd-pstate.h @@ -49,6 +49,10 @@ struct amd_aperf_mperf { * @lowest_perf: the absolute lowest performance level of the processor * @prefcore_ranking: the preferred core ranking, the higher value indicates a higher * priority. + * @min_limit_perf: Cached value of the performance corresponding to policy->min + * @max_limit_perf: Cached value of the performance corresponding to policy->max + * @min_limit_freq: Cached value of policy->min + * @max_limit_freq: Cached value of policy->max * @max_freq: the frequency that mapped to highest_perf * @min_freq: the frequency that mapped to lowest_perf * @nominal_freq: the frequency that mapped to nominal_perf From 4fcfd1954ad305e331b6b4b62de2874fbae61394 Mon Sep 17 00:00:00 2001 From: "Gautham R. Shenoy" Date: Thu, 25 Apr 2024 16:07:52 +0800 Subject: [PATCH 02/11] cpufreq: amd-pstate: Document the units for freq variables in amd_cpudata The min_limit_freq, max_limit_freq, min_freq, max_freq, nominal_freq and the lowest_nominal_freq members of struct cpudata store the frequency value in khz to be consistent with the cpufreq core. Update the comment to document this. Reviewed-by: Li Meng Tested-by: Dhananjay Ugwekar Signed-off-by: Gautham R. Shenoy Signed-off-by: Perry Yuan Acked-by: Huang Rui Signed-off-by: Rafael J. Wysocki --- include/linux/amd-pstate.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h index 83fb3fc647fce..ec0b0fa3e9bb4 100644 --- a/include/linux/amd-pstate.h +++ b/include/linux/amd-pstate.h @@ -51,15 +51,15 @@ struct amd_aperf_mperf { * priority. * @min_limit_perf: Cached value of the performance corresponding to policy->min * @max_limit_perf: Cached value of the performance corresponding to policy->max - * @min_limit_freq: Cached value of policy->min - * @max_limit_freq: Cached value of policy->max - * @max_freq: the frequency that mapped to highest_perf - * @min_freq: the frequency that mapped to lowest_perf - * @nominal_freq: the frequency that mapped to nominal_perf - * @lowest_nonlinear_freq: the frequency that mapped to lowest_nonlinear_perf + * @min_limit_freq: Cached value of policy->min (in khz) + * @max_limit_freq: Cached value of policy->max (in khz) + * @max_freq: the frequency (in khz) that mapped to highest_perf + * @min_freq: the frequency (in khz) that mapped to lowest_perf + * @nominal_freq: the frequency (in khz) that mapped to nominal_perf + * @lowest_nonlinear_freq: the frequency (in khz) that mapped to lowest_nonlinear_perf * @cur: Difference of Aperf/Mperf/tsc count between last and current sample * @prev: Last Aperf/Mperf/tsc count value read from register - * @freq: current cpu frequency value + * @freq: current cpu frequency value (in khz) * @boost_supported: check whether the Processor or SBIOS supports boost mode * @hw_prefcore: check whether HW supports preferred core featue. * Only when hw_prefcore and early prefcore param are true, From 5547c0ebfc2efdab6ee93a7fd4d9c411ad87013e Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Thu, 25 Apr 2024 16:07:53 +0800 Subject: [PATCH 03/11] cpufreq: amd-pstate: Unify computation of {max,min,nominal,lowest_nonlinear}_freq Currently the amd_get_{min, max, nominal, lowest_nonlinear}_freq() helpers computes the values of min_freq, max_freq, nominal_freq and lowest_nominal_freq respectively afresh from cppc_get_perf_caps(). This is not necessary as there are fields in cpudata to cache these values. To simplify this, add a single helper function named amd_pstate_init_freq() which computes all these frequencies at once, and caches it in cpudata. Use the cached values everywhere else in the code. Acked-by: Huang Rui Reviewed-by: Li Meng Tested-by: Dhananjay Ugwekar Co-developed-by: Gautham R. Shenoy Signed-off-by: Gautham R. Shenoy Signed-off-by: Perry Yuan Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/amd-pstate.c | 126 ++++++++++++++++------------------- 1 file changed, 59 insertions(+), 67 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 2015c9fcc3c91..891fad6f90e14 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -606,74 +606,22 @@ static void amd_pstate_adjust_perf(unsigned int cpu, static int amd_get_min_freq(struct amd_cpudata *cpudata) { - struct cppc_perf_caps cppc_perf; - - int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); - if (ret) - return ret; - - /* Switch to khz */ - return cppc_perf.lowest_freq * 1000; + return READ_ONCE(cpudata->min_freq); } static int amd_get_max_freq(struct amd_cpudata *cpudata) { - struct cppc_perf_caps cppc_perf; - u32 max_perf, max_freq, nominal_freq, nominal_perf; - u64 boost_ratio; - - int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); - if (ret) - return ret; - - nominal_freq = cppc_perf.nominal_freq; - nominal_perf = READ_ONCE(cpudata->nominal_perf); - max_perf = READ_ONCE(cpudata->highest_perf); - - boost_ratio = div_u64(max_perf << SCHED_CAPACITY_SHIFT, - nominal_perf); - - max_freq = nominal_freq * boost_ratio >> SCHED_CAPACITY_SHIFT; - - /* Switch to khz */ - return max_freq * 1000; + return READ_ONCE(cpudata->max_freq); } static int amd_get_nominal_freq(struct amd_cpudata *cpudata) { - struct cppc_perf_caps cppc_perf; - - int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); - if (ret) - return ret; - - /* Switch to khz */ - return cppc_perf.nominal_freq * 1000; + return READ_ONCE(cpudata->nominal_freq); } static int amd_get_lowest_nonlinear_freq(struct amd_cpudata *cpudata) { - struct cppc_perf_caps cppc_perf; - u32 lowest_nonlinear_freq, lowest_nonlinear_perf, - nominal_freq, nominal_perf; - u64 lowest_nonlinear_ratio; - - int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); - if (ret) - return ret; - - nominal_freq = cppc_perf.nominal_freq; - nominal_perf = READ_ONCE(cpudata->nominal_perf); - - lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf; - - lowest_nonlinear_ratio = div_u64(lowest_nonlinear_perf << SCHED_CAPACITY_SHIFT, - nominal_perf); - - lowest_nonlinear_freq = nominal_freq * lowest_nonlinear_ratio >> SCHED_CAPACITY_SHIFT; - - /* Switch to khz */ - return lowest_nonlinear_freq * 1000; + return READ_ONCE(cpudata->lowest_nonlinear_freq); } static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state) @@ -828,6 +776,53 @@ static void amd_pstate_update_limits(unsigned int cpu) mutex_unlock(&amd_pstate_driver_lock); } +/** + * amd_pstate_init_freq: Initialize the max_freq, min_freq, + * nominal_freq and lowest_nonlinear_freq for + * the @cpudata object. + * + * Requires: highest_perf, lowest_perf, nominal_perf and + * lowest_nonlinear_perf members of @cpudata to be + * initialized. + * + * Returns 0 on success, non-zero value on failure. + */ +static int amd_pstate_init_freq(struct amd_cpudata *cpudata) +{ + int ret; + u32 min_freq; + u32 highest_perf, max_freq; + u32 nominal_perf, nominal_freq; + u32 lowest_nonlinear_perf, lowest_nonlinear_freq; + u32 boost_ratio, lowest_nonlinear_ratio; + struct cppc_perf_caps cppc_perf; + + + ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); + if (ret) + return ret; + + min_freq = cppc_perf.lowest_freq * 1000; + nominal_freq = cppc_perf.nominal_freq; + nominal_perf = READ_ONCE(cpudata->nominal_perf); + + highest_perf = READ_ONCE(cpudata->highest_perf); + boost_ratio = div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf); + max_freq = (nominal_freq * boost_ratio >> SCHED_CAPACITY_SHIFT) * 1000; + + lowest_nonlinear_perf = READ_ONCE(cpudata->lowest_nonlinear_perf); + lowest_nonlinear_ratio = div_u64(lowest_nonlinear_perf << SCHED_CAPACITY_SHIFT, + nominal_perf); + lowest_nonlinear_freq = (nominal_freq * lowest_nonlinear_ratio >> SCHED_CAPACITY_SHIFT) * 1000; + + WRITE_ONCE(cpudata->min_freq, min_freq); + WRITE_ONCE(cpudata->lowest_nonlinear_freq, lowest_nonlinear_freq); + WRITE_ONCE(cpudata->nominal_freq, nominal_freq); + WRITE_ONCE(cpudata->max_freq, max_freq); + + return 0; +} + static int amd_pstate_cpu_init(struct cpufreq_policy *policy) { int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret; @@ -855,6 +850,10 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) if (ret) goto free_cpudata1; + ret = amd_pstate_init_freq(cpudata); + if (ret) + goto free_cpudata1; + min_freq = amd_get_min_freq(cpudata); max_freq = amd_get_max_freq(cpudata); nominal_freq = amd_get_nominal_freq(cpudata); @@ -896,13 +895,8 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) goto free_cpudata2; } - /* Initial processor data capability frequencies */ - cpudata->max_freq = max_freq; - cpudata->min_freq = min_freq; cpudata->max_limit_freq = max_freq; cpudata->min_limit_freq = min_freq; - cpudata->nominal_freq = nominal_freq; - cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq; policy->driver_data = cpudata; @@ -1317,6 +1311,10 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) if (ret) goto free_cpudata1; + ret = amd_pstate_init_freq(cpudata); + if (ret) + goto free_cpudata1; + min_freq = amd_get_min_freq(cpudata); max_freq = amd_get_max_freq(cpudata); nominal_freq = amd_get_nominal_freq(cpudata); @@ -1333,12 +1331,6 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) /* It will be updated by governor */ policy->cur = policy->cpuinfo.min_freq; - /* Initial processor data capability frequencies */ - cpudata->max_freq = max_freq; - cpudata->min_freq = min_freq; - cpudata->nominal_freq = nominal_freq; - cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq; - policy->driver_data = cpudata; cpudata->epp_cached = amd_pstate_get_epp(cpudata, 0); From 3cbbe8871a2fb8f454e740f3e04ff2e29b573abe Mon Sep 17 00:00:00 2001 From: "Gautham R. Shenoy" Date: Thu, 25 Apr 2024 16:07:54 +0800 Subject: [PATCH 04/11] cpufreq: amd-pstate: Remove amd_get_{min,max,nominal,lowest_nonlinear}_freq() amd_get_{min,max,nominal,lowest_nonlinear}_freq() functions merely return cpudata->{min,max,nominal,lowest_nonlinear}_freq values. There is no loss in readability in replacing their invocations by accesses to the corresponding members of cpudata. Do so and remove these helper functions. Acked-by: Huang Rui Reviewed-by: Li Meng Tested-by: Dhananjay Ugwekar Signed-off-by: Gautham R. Shenoy Signed-off-by: Perry Yuan Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/amd-pstate.c | 40 +++++++++--------------------------- 1 file changed, 10 insertions(+), 30 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 891fad6f90e14..3836d62b54ef3 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -604,26 +604,6 @@ static void amd_pstate_adjust_perf(unsigned int cpu, cpufreq_cpu_put(policy); } -static int amd_get_min_freq(struct amd_cpudata *cpudata) -{ - return READ_ONCE(cpudata->min_freq); -} - -static int amd_get_max_freq(struct amd_cpudata *cpudata) -{ - return READ_ONCE(cpudata->max_freq); -} - -static int amd_get_nominal_freq(struct amd_cpudata *cpudata) -{ - return READ_ONCE(cpudata->nominal_freq); -} - -static int amd_get_lowest_nonlinear_freq(struct amd_cpudata *cpudata) -{ - return READ_ONCE(cpudata->lowest_nonlinear_freq); -} - static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state) { struct amd_cpudata *cpudata = policy->driver_data; @@ -854,10 +834,10 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) if (ret) goto free_cpudata1; - min_freq = amd_get_min_freq(cpudata); - max_freq = amd_get_max_freq(cpudata); - nominal_freq = amd_get_nominal_freq(cpudata); - lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata); + min_freq = READ_ONCE(cpudata->min_freq); + max_freq = READ_ONCE(cpudata->max_freq); + nominal_freq = READ_ONCE(cpudata->nominal_freq); + lowest_nonlinear_freq = READ_ONCE(cpudata->lowest_nonlinear_freq); if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) { dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n", @@ -960,7 +940,7 @@ static ssize_t show_amd_pstate_max_freq(struct cpufreq_policy *policy, int max_freq; struct amd_cpudata *cpudata = policy->driver_data; - max_freq = amd_get_max_freq(cpudata); + max_freq = READ_ONCE(cpudata->max_freq); if (max_freq < 0) return max_freq; @@ -973,7 +953,7 @@ static ssize_t show_amd_pstate_lowest_nonlinear_freq(struct cpufreq_policy *poli int freq; struct amd_cpudata *cpudata = policy->driver_data; - freq = amd_get_lowest_nonlinear_freq(cpudata); + freq = READ_ONCE(cpudata->lowest_nonlinear_freq); if (freq < 0) return freq; @@ -1315,10 +1295,10 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) if (ret) goto free_cpudata1; - min_freq = amd_get_min_freq(cpudata); - max_freq = amd_get_max_freq(cpudata); - nominal_freq = amd_get_nominal_freq(cpudata); - lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata); + min_freq = READ_ONCE(cpudata->min_freq); + max_freq = READ_ONCE(cpudata->max_freq); + nominal_freq = READ_ONCE(cpudata->nominal_freq); + lowest_nonlinear_freq = READ_ONCE(cpudata->lowest_nonlinear_freq); if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) { dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n", min_freq, max_freq); From 2ddb8a3946d4d02115b2dca53c5493ff00536002 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Thu, 25 Apr 2024 16:07:55 +0800 Subject: [PATCH 05/11] cpufreq: amd-pstate: Bail out if min/max/nominal_freq is 0 The amd-pstate driver cannot work when the min_freq, nominal_freq or the max_freq is zero. When this happens it is prudent to error out early on rather than waiting failing at the time of the governor initialization. Acked-by: Huang Rui Reviewed-by: Gautham R. Shenoy Tested-by: Dhananjay Ugwekar Signed-off-by: Perry Yuan Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/amd-pstate.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 3836d62b54ef3..960fead0b83e2 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -839,9 +839,11 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) nominal_freq = READ_ONCE(cpudata->nominal_freq); lowest_nonlinear_freq = READ_ONCE(cpudata->lowest_nonlinear_freq); - if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) { - dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n", - min_freq, max_freq); + if (min_freq <= 0 || max_freq <= 0 || + nominal_freq <= 0 || min_freq > max_freq) { + dev_err(dev, + "min_freq(%d) or max_freq(%d) or nominal_freq (%d) value is incorrect, check _CPC in ACPI tables\n", + min_freq, max_freq, nominal_freq); ret = -EINVAL; goto free_cpudata1; } @@ -1299,9 +1301,11 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) max_freq = READ_ONCE(cpudata->max_freq); nominal_freq = READ_ONCE(cpudata->nominal_freq); lowest_nonlinear_freq = READ_ONCE(cpudata->lowest_nonlinear_freq); - if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) { - dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n", - min_freq, max_freq); + if (min_freq <= 0 || max_freq <= 0 || + nominal_freq <= 0 || min_freq > max_freq) { + dev_err(dev, + "min_freq(%d) or max_freq(%d) or nominal_freq(%d) value is incorrect, check _CPC in ACPI tables\n", + min_freq, max_freq, nominal_freq); ret = -EINVAL; goto free_cpudata1; } From 069a2bb8c48c43176f2f0e6cae5efe2f39f6bdf2 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Thu, 25 Apr 2024 16:07:56 +0800 Subject: [PATCH 06/11] cpufreq: amd-pstate: get transition delay and latency value from ACPI tables Make pstate driver initially retrieve the P-state transition delay and latency values from the BIOS ACPI tables which has more reasonable delay and latency values according to the platform design and requirements. Previously there values were hardcoded at specific value which may have conflicted with platform and it might not reflect the most accurate or optimized setting for the processor. [054h 0084 8] Preserve Mask : FFFFFFFF00000000 [05Ch 0092 8] Write Mask : 0000000000000001 [064h 0100 4] Command Latency : 00000FA0 [068h 0104 4] Maximum Access Rate : 0000EA60 [06Ch 0108 2] Minimum Turnaround Time : 0000 Reviewed-by: Gautham R. Shenoy Reviewed-by: Mario Limonciello Tested-by: Dhananjay Ugwekar Signed-off-by: Perry Yuan Acked-by: Huang Rui Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/amd-pstate.c | 34 ++++++++++++++++++++++++++++++++-- 1 file changed, 32 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 960fead0b83e2..510b5aec42ea0 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -756,6 +756,36 @@ static void amd_pstate_update_limits(unsigned int cpu) mutex_unlock(&amd_pstate_driver_lock); } +/** + * Get pstate transition delay time from ACPI tables that firmware set + * instead of using hardcode value directly. + */ +static u32 amd_pstate_get_transition_delay_us(unsigned int cpu) +{ + u32 transition_delay_ns; + + transition_delay_ns = cppc_get_transition_latency(cpu); + if (transition_delay_ns == CPUFREQ_ETERNAL) + return AMD_PSTATE_TRANSITION_DELAY; + + return transition_delay_ns / NSEC_PER_USEC; +} + +/** + * Get pstate transition latency value from ACPI tables that firmware + * set instead of using hardcode value directly. + */ +static u32 amd_pstate_get_transition_latency(unsigned int cpu) +{ + u32 transition_latency; + + transition_latency = cppc_get_transition_latency(cpu); + if (transition_latency == CPUFREQ_ETERNAL) + return AMD_PSTATE_TRANSITION_LATENCY; + + return transition_latency; +} + /** * amd_pstate_init_freq: Initialize the max_freq, min_freq, * nominal_freq and lowest_nonlinear_freq for @@ -848,8 +878,8 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) goto free_cpudata1; } - policy->cpuinfo.transition_latency = AMD_PSTATE_TRANSITION_LATENCY; - policy->transition_delay_us = AMD_PSTATE_TRANSITION_DELAY; + policy->cpuinfo.transition_latency = amd_pstate_get_transition_latency(policy->cpu); + policy->transition_delay_us = amd_pstate_get_transition_delay_us(policy->cpu); policy->min = min_freq; policy->max = max_freq; From 5f8f9bc4d7bc8d44031b88b548c2572b746e2611 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Thu, 25 Apr 2024 16:07:57 +0800 Subject: [PATCH 07/11] cppc_acpi: print error message if CPPC is unsupported The amd-pstate driver can fail when _CPC objects are not supported by the CPU. However, the current error message is ambiguous (see below) and there is no clear way for attributing the failure of the amd-pstate driver to the lack of CPPC support. [ 0.477523] amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled Fix this by adding an debug message to notify the user if the amd-pstate driver failed to load due to CPPC not be supported by the CPU Reviewed-by: Mario Limonciello Reviewed-by: Gautham R. Shenoy Tested-by: Dhananjay Ugwekar Signed-off-by: Perry Yuan Acked-by: Huang Rui Signed-off-by: Rafael J. Wysocki --- drivers/acpi/cppc_acpi.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 4bfbe55553f41..3134101f31b69 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -686,8 +686,10 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr) if (!osc_sb_cppc2_support_acked) { pr_debug("CPPC v2 _OSC not acked\n"); - if (!cpc_supported_by_cpu()) + if (!cpc_supported_by_cpu()) { + pr_debug("CPPC is not supported by the CPU\n"); return -ENODEV; + } } /* Parse the ACPI _CPC table for this CPU. */ From eb8b6c36820214df96e7e86d8614d93f6b028f28 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Thu, 25 Apr 2024 16:07:58 +0800 Subject: [PATCH 08/11] cpufreq: amd-pstate: Add quirk for the pstate CPPC capabilities missing Add quirks table to get CPPC capabilities issue fixed by providing correct perf or frequency values while driver loading. If CPPC capabilities are not defined in the ACPI tables or wrongly defined by platform firmware, it needs to use quick to get those issues fixed with correct workaround values to make pstate driver can be loaded even though there are CPPC capabilities errors. The workaround will match the broken BIOS which lack of CPPC capabilities nominal_freq and lowest_freq definition in the ACPI table. $ cat /sys/devices/system/cpu/cpu0/acpi_cppc/lowest_freq 0 $ cat /sys/devices/system/cpu/cpu0/acpi_cppc/nominal_freq 0 Acked-by: Huang Rui Reviewed-by: Mario Limonciello Reviewed-by: Gautham R. Shenoy Tested-by: Dhananjay Ugwekar Signed-off-by: Perry Yuan Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/amd-pstate.c | 53 ++++++++++++++++++++++++++++++++++-- include/linux/amd-pstate.h | 6 ++++ 2 files changed, 57 insertions(+), 2 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 510b5aec42ea0..83a29b257794b 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -67,6 +67,7 @@ static struct cpufreq_driver amd_pstate_epp_driver; static int cppc_state = AMD_PSTATE_UNDEFINED; static bool cppc_enabled; static bool amd_pstate_prefcore = true; +static struct quirk_entry *quirks; /* * AMD Energy Preference Performance (EPP) @@ -111,6 +112,41 @@ static unsigned int epp_values[] = { typedef int (*cppc_mode_transition_fn)(int); +static struct quirk_entry quirk_amd_7k62 = { + .nominal_freq = 2600, + .lowest_freq = 550, +}; + +static int __init dmi_matched_7k62_bios_bug(const struct dmi_system_id *dmi) +{ + /** + * match the broken bios for family 17h processor support CPPC V2 + * broken BIOS lack of nominal_freq and lowest_freq capabilities + * definition in ACPI tables + */ + if (boot_cpu_has(X86_FEATURE_ZEN2)) { + quirks = dmi->driver_data; + pr_info("Overriding nominal and lowest frequencies for %s\n", dmi->ident); + return 1; + } + + return 0; +} + +static const struct dmi_system_id amd_pstate_quirks_table[] __initconst = { + { + .callback = dmi_matched_7k62_bios_bug, + .ident = "AMD EPYC 7K62", + .matches = { + DMI_MATCH(DMI_BIOS_VERSION, "5.14"), + DMI_MATCH(DMI_BIOS_RELEASE, "12/12/2019"), + }, + .driver_data = &quirk_amd_7k62, + }, + {} +}; +MODULE_DEVICE_TABLE(dmi, amd_pstate_quirks_table); + static inline int get_mode_idx_from_str(const char *str, size_t size) { int i; @@ -812,8 +848,16 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata) if (ret) return ret; - min_freq = cppc_perf.lowest_freq * 1000; - nominal_freq = cppc_perf.nominal_freq; + if (quirks && quirks->lowest_freq) + min_freq = quirks->lowest_freq * 1000; + else + min_freq = cppc_perf.lowest_freq * 1000; + + if (quirks && quirks->nominal_freq) + nominal_freq = quirks->nominal_freq ; + else + nominal_freq = cppc_perf.nominal_freq; + nominal_perf = READ_ONCE(cpudata->nominal_perf); highest_perf = READ_ONCE(cpudata->highest_perf); @@ -1662,6 +1706,11 @@ static int __init amd_pstate_init(void) if (cpufreq_get_current_driver()) return -EEXIST; + quirks = NULL; + + /* check if this machine need CPPC quirks */ + dmi_check_system(amd_pstate_quirks_table); + switch (cppc_state) { case AMD_PSTATE_UNDEFINED: /* Disable on the following configs by default: diff --git a/include/linux/amd-pstate.h b/include/linux/amd-pstate.h index ec0b0fa3e9bb4..d58fc022ec466 100644 --- a/include/linux/amd-pstate.h +++ b/include/linux/amd-pstate.h @@ -128,4 +128,10 @@ static const char * const amd_pstate_mode_string[] = { [AMD_PSTATE_GUIDED] = "guided", NULL, }; + +struct quirk_entry { + u32 nominal_freq; + u32 lowest_freq; +}; + #endif /* _LINUX_AMD_PSTATE_H */ From 5131a3ca3518d726cb535543441a5f195b8b0299 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Tue, 30 Apr 2024 15:48:56 +0800 Subject: [PATCH 09/11] cpufreq: amd-pstate: fix code format problems get some code format problems fixed in the amd-pstate driver. Changes Made: - Fixed incorrect comment format in the functions. - Removed unnecessary blank line. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202404271148.HK9yHBlB-lkp@intel.com/ Signed-off-by: Perry Yuan Reviewed-by: Mario Limonciello Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/amd-pstate.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 83a29b257794b..85656342a1014 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -792,7 +792,7 @@ static void amd_pstate_update_limits(unsigned int cpu) mutex_unlock(&amd_pstate_driver_lock); } -/** +/* * Get pstate transition delay time from ACPI tables that firmware set * instead of using hardcode value directly. */ @@ -807,7 +807,7 @@ static u32 amd_pstate_get_transition_delay_us(unsigned int cpu) return transition_delay_ns / NSEC_PER_USEC; } -/** +/* * Get pstate transition latency value from ACPI tables that firmware * set instead of using hardcode value directly. */ @@ -822,7 +822,7 @@ static u32 amd_pstate_get_transition_latency(unsigned int cpu) return transition_latency; } -/** +/* * amd_pstate_init_freq: Initialize the max_freq, min_freq, * nominal_freq and lowest_nonlinear_freq for * the @cpudata object. @@ -843,7 +843,6 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata) u32 boost_ratio, lowest_nonlinear_ratio; struct cppc_perf_caps cppc_perf; - ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); if (ret) return ret; From 5c3fd1edaa8b4c093e877f6354b3745178015070 Mon Sep 17 00:00:00 2001 From: Perry Yuan Date: Tue, 30 Apr 2024 15:48:57 +0800 Subject: [PATCH 10/11] cpufreq: amd-pstate: remove unused variable lowest_nonlinear_freq removed the unused variable `lowest_nonlinear_freq` for build warning. This variable was defined and assigned a value in the previous code, but it was not used in the subsequent code. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202404271038.em6nJjzy-lkp@intel.com/ Signed-off-by: Perry Yuan Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/amd-pstate.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 85656342a1014..2db095867d039 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -878,7 +878,7 @@ static int amd_pstate_init_freq(struct amd_cpudata *cpudata) static int amd_pstate_cpu_init(struct cpufreq_policy *policy) { - int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret; + int min_freq, max_freq, nominal_freq, ret; struct device *dev; struct amd_cpudata *cpudata; @@ -910,7 +910,6 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) min_freq = READ_ONCE(cpudata->min_freq); max_freq = READ_ONCE(cpudata->max_freq); nominal_freq = READ_ONCE(cpudata->nominal_freq); - lowest_nonlinear_freq = READ_ONCE(cpudata->lowest_nonlinear_freq); if (min_freq <= 0 || max_freq <= 0 || nominal_freq <= 0 || min_freq > max_freq) { @@ -1339,7 +1338,7 @@ static bool amd_pstate_acpi_pm_profile_undefined(void) static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) { - int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret; + int min_freq, max_freq, nominal_freq, ret; struct amd_cpudata *cpudata; struct device *dev; u64 value; @@ -1373,7 +1372,6 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) min_freq = READ_ONCE(cpudata->min_freq); max_freq = READ_ONCE(cpudata->max_freq); nominal_freq = READ_ONCE(cpudata->nominal_freq); - lowest_nonlinear_freq = READ_ONCE(cpudata->lowest_nonlinear_freq); if (min_freq <= 0 || max_freq <= 0 || nominal_freq <= 0 || min_freq > max_freq) { dev_err(dev, From 70f83f525304079746e53027963cd732543e11c8 Mon Sep 17 00:00:00 2001 From: Huang Rui Date: Mon, 29 Apr 2024 19:33:56 +0800 Subject: [PATCH 11/11] MAINTAINERS: cpufreq: amd-pstate: Add co-maintainers and reviewer I'm happy to add Gautham and Mario as the co-maintainers, Perry as the reviewer for amd-pstate driver. Signed-off-by: Huang Rui Acked-by: Mario Limonciello Signed-off-by: Rafael J. Wysocki --- MAINTAINERS | 3 +++ 1 file changed, 3 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index 7c121493f43d0..8c141c89eeaf6 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1062,6 +1062,9 @@ F: drivers/gpu/drm/amd/pm/ AMD PSTATE DRIVER M: Huang Rui +M: Gautham R. Shenoy +M: Mario Limonciello +R: Perry Yuan L: linux-pm@vger.kernel.org S: Supported F: Documentation/admin-guide/pm/amd-pstate.rst