diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 8b432d6e846d..c9ce716247c1 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -126,6 +126,49 @@ static void cppc_cpufreq_stop_cpu(struct cpufreq_policy *policy) cpu->perf_caps.lowest_perf, cpu_num, ret); } +/* + * The PCC subspace describes the rate at which platform can accept commands + * on the shared PCC channel (including READs which do not count towards freq + * trasition requests), so ideally we need to use the PCC values as a fallback + * if we don't have a platform specific transition_delay_us + */ +#ifdef CONFIG_ARM64 +#include + +static unsigned int cppc_cpufreq_get_transition_delay_us(int cpu) +{ + unsigned long implementor = read_cpuid_implementor(); + unsigned long part_num = read_cpuid_part_number(); + unsigned int delay_us = 0; + + switch (implementor) { + case ARM_CPU_IMP_QCOM: + switch (part_num) { + case QCOM_CPU_PART_FALKOR_V1: + case QCOM_CPU_PART_FALKOR: + delay_us = 10000; + break; + default: + delay_us = cppc_get_transition_latency(cpu) / NSEC_PER_USEC; + break; + } + break; + default: + delay_us = cppc_get_transition_latency(cpu) / NSEC_PER_USEC; + break; + } + + return delay_us; +} + +#else + +static unsigned int cppc_cpufreq_get_transition_delay_us(int cpu) +{ + return cppc_get_transition_latency(cpu) / NSEC_PER_USEC; +} +#endif + static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) { struct cppc_cpudata *cpu; @@ -163,8 +206,7 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) policy->cpuinfo.max_freq = cppc_dmi_max_khz; policy->cpuinfo.transition_latency = cppc_get_transition_latency(cpu_num); - policy->transition_delay_us = cppc_get_transition_latency(cpu_num) / - NSEC_PER_USEC; + policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu_num); policy->shared_type = cpu->shared_type; if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {