On 4/20/2021 9:38 PM, Huang Rui wrote: > Some AMD Ryzen generations has different calculation method on maximum > perf. 255 is not for all asics, some specific generations should use 166 > as the maximum perf. Otherwise, it will report incorrect frequency value > like below: > > ~ → lscpu | grep MHz > CPU MHz: 3400.000 > CPU max MHz: 7228.3198 > CPU min MHz: 2200.0000 > > Fixes: 41ea667227ba ("x86, sched: Calculate frequency invariance for AMD systems") > Fixes: 3c55e94c0ade ("cpufreq: ACPI: Extend frequency tables to cover boost frequencies") > > Reported-by: Jason Bagavatsingham <jason.bagavatsingham@xxxxxxxxx> > Tested-by: Jason Bagavatsingham <jason.bagavatsingham@xxxxxxxxx> > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211791 > Signed-off-by: Huang Rui <ray.huang@xxxxxxx> > Cc: Alex Deucher <alexander.deucher@xxxxxxx> > Cc: Nathan Fontenot <nathan.fontenot@xxxxxxx> > Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > Cc: Borislav Petkov <bp@xxxxxxx> > Cc: x86@xxxxxxxxxx > Cc: stable@xxxxxxxxxxxxxxx > --- > > Changes from V1 -> V2: > - Enhance the commit message. > - Move amd_get_highest_perf() into amd.c. > - Refine the implementation of switch-case. > - Cc stable mail list. > > --- > arch/x86/include/asm/processor.h | 2 ++ > arch/x86/kernel/cpu/amd.c | 22 ++++++++++++++++++++++ > arch/x86/kernel/smpboot.c | 2 +- > drivers/cpufreq/acpi-cpufreq.c | 19 +++++++++++++++++++ > 4 files changed, 44 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h > index f1b9ed5efaa9..908bcaea1361 100644 > --- a/arch/x86/include/asm/processor.h > +++ b/arch/x86/include/asm/processor.h > @@ -804,8 +804,10 @@ DECLARE_PER_CPU(u64, msr_misc_features_shadow); > > #ifdef CONFIG_CPU_SUP_AMD > extern u32 amd_get_nodes_per_socket(void); > +extern u32 amd_get_highest_perf(void); > #else > static inline u32 amd_get_nodes_per_socket(void) { return 0; } > +static inline u32 amd_get_highest_perf(void) { return 0; } > #endif > > static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves) > diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c > index 347a956f71ca..aadb691d9357 100644 > --- a/arch/x86/kernel/cpu/amd.c > +++ b/arch/x86/kernel/cpu/amd.c > @@ -1170,3 +1170,25 @@ void set_dr_addr_mask(unsigned long mask, int dr) > break; > } > } > + > +u32 amd_get_highest_perf(void) > +{ > + struct cpuinfo_x86 *c = &boot_cpu_data; > + u32 cppc_max_perf = 225; > + > + switch (c->x86) { > + case 0x17: > + if ((c->x86_model >= 0x30 && c->x86_model < 0x40) || > + (c->x86_model >= 0x70 && c->x86_model < 0x80)) > + cppc_max_perf = 166; > + break; > + case 0x19: > + if ((c->x86_model >= 0x20 && c->x86_model < 0x30) || > + (c->x86_model >= 0x40 && c->x86_model < 0x70)) > + cppc_max_perf = 166; > + break; > + } > + > + return cppc_max_perf; > +} > +EXPORT_SYMBOL_GPL(amd_get_highest_perf); Should this be an update to cpp_get_perf_caps()? This approach would ensure that all callers have the correct value and remove the need to fix up individual callers to use this new routine to get the correct value. -Nathan > diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c > index 02813a7f3a7c..7bec57d04a87 100644 > --- a/arch/x86/kernel/smpboot.c > +++ b/arch/x86/kernel/smpboot.c > @@ -2046,7 +2046,7 @@ static bool amd_set_max_freq_ratio(void) > return false; > } > > - highest_perf = perf_caps.highest_perf; > + highest_perf = amd_get_highest_perf(); > nominal_perf = perf_caps.nominal_perf; > > if (!highest_perf || !nominal_perf) { > diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c > index d1bbc16fba4b..3f0a19dd658c 100644 > --- a/drivers/cpufreq/acpi-cpufreq.c > +++ b/drivers/cpufreq/acpi-cpufreq.c > @@ -630,6 +630,22 @@ static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c) > #endif > > #ifdef CONFIG_ACPI_CPPC_LIB > + > +static u64 get_amd_max_boost_ratio(unsigned int cpu, u64 nominal_perf) > +{ > + u64 boost_ratio, cppc_max_perf; > + > + if (!nominal_perf) > + return 0; > + > + cppc_max_perf = amd_get_highest_perf(); > + > + boost_ratio = div_u64(cppc_max_perf << SCHED_CAPACITY_SHIFT, > + nominal_perf); > + > + return boost_ratio; > +} > + > static u64 get_max_boost_ratio(unsigned int cpu) > { > struct cppc_perf_caps perf_caps; > @@ -646,6 +662,9 @@ static u64 get_max_boost_ratio(unsigned int cpu) > return 0; > } > > + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) > + return get_amd_max_boost_ratio(cpu, perf_caps.nominal_perf); > + > highest_perf = perf_caps.highest_perf; > nominal_perf = perf_caps.nominal_perf; > > -- > 2.25.1 >