| Message ID | ee3c290dcdce4a746fbd882d37e9a45504a5ae3d.1711335714.git.perry.yuan@amd.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | AMD Pstate Fixes And Enhancements | expand |
On Mon, Mar 25, 2024 at 11:03:26AM +0800, Yuan, Perry wrote: > 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 <gautham.shenoy@amd.com> > Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> > Tested-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com> > Signed-off-by: Perry Yuan <perry.yuan@amd.com> Acked-by: Huang Rui <ray.huang@amd.com> > --- > 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 6708c436e1a2..ec049b62b366 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; > -- > 2.34.1 >
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 6708c436e1a2..ec049b62b366 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;