From a2fed573f065e526bfd5cbf26e5491973d9e9aaa Mon Sep 17 00:00:00 2001 From: Mark Langsdorf Date: Thu, 18 Mar 2010 18:41:46 +0100 Subject: x86, cpufreq: Add APERF/MPERF support for AMD processors Starting with model 10 of Family 0x10, AMD processors may have support for APERF/MPERF. Add support for identifying it and using it within cpufreq. Move the APERF/MPERF functions out of the acpi-cpufreq code and into their own file so they can easily be shared. Signed-off-by: Mark Langsdorf LKML-Reference: <20100401141956.GA1930@aftab> Signed-off-by: Borislav Petkov Reviewed-by: Thomas Renninger Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 44 ++---------------------------- 1 file changed, 2 insertions(+), 42 deletions(-) (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c') diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 1b1920fa7c80..dc68e5c2c071 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -45,6 +45,7 @@ #include #include #include +#include "mperf.h" #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \ "acpi-cpufreq", msg) @@ -70,8 +71,6 @@ struct acpi_cpufreq_data { static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data); -static DEFINE_PER_CPU(struct aperfmperf, acfreq_old_perf); - /* acpi_perf_data is a pointer to percpu data. */ static struct acpi_processor_performance *acpi_perf_data; @@ -239,45 +238,6 @@ static u32 get_cur_val(const struct cpumask *mask) return cmd.val; } -/* Called via smp_call_function_single(), on the target CPU */ -static void read_measured_perf_ctrs(void *_cur) -{ - struct aperfmperf *am = _cur; - - get_aperfmperf(am); -} - -/* - * Return the measured active (C0) frequency on this CPU since last call - * to this function. - * Input: cpu number - * Return: Average CPU frequency in terms of max frequency (zero on error) - * - * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance - * over a period of time, while CPU is in C0 state. - * IA32_MPERF counts at the rate of max advertised frequency - * IA32_APERF counts at the rate of actual CPU frequency - * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and - * no meaning should be associated with absolute values of these MSRs. - */ -static unsigned int get_measured_perf(struct cpufreq_policy *policy, - unsigned int cpu) -{ - struct aperfmperf perf; - unsigned long ratio; - unsigned int retval; - - if (smp_call_function_single(cpu, read_measured_perf_ctrs, &perf, 1)) - return 0; - - ratio = calc_aperfmperf_ratio(&per_cpu(acfreq_old_perf, cpu), &perf); - per_cpu(acfreq_old_perf, cpu) = perf; - - retval = (policy->cpuinfo.max_freq * ratio) >> APERFMPERF_SHIFT; - - return retval; -} - static unsigned int get_cur_freq_on_cpu(unsigned int cpu) { struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu); @@ -701,7 +661,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) /* Check for APERF/MPERF support in hardware */ if (cpu_has(c, X86_FEATURE_APERFMPERF)) - acpi_cpufreq_driver.getavg = get_measured_perf; + acpi_cpufreq_driver.getavg = cpufreq_get_measured_perf; dprintk("CPU%u - ACPI performance management activated.\n", cpu); for (i = 0; i < perf->state_count; i++) -- cgit v1.2.2