diff options
Diffstat (limited to 'arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c')
-rw-r--r-- | arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 23da96e57b1..19f6b9d27e8 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -33,7 +33,7 @@ #include <linux/cpufreq.h> #include <linux/compiler.h> #include <linux/dmi.h> -#include <linux/ftrace.h> +#include <trace/power.h> #include <linux/acpi.h> #include <linux/io.h> @@ -72,6 +72,8 @@ struct acpi_cpufreq_data { static DEFINE_PER_CPU(struct acpi_cpufreq_data *, drv_data); +DEFINE_TRACE(power_mark); + /* acpi_perf_data is a pointer to percpu data. */ static struct acpi_processor_performance *acpi_perf_data; @@ -680,6 +682,18 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy) perf->states[i].transition_latency * 1000; } + /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */ + if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE && + policy->cpuinfo.transition_latency > 20 * 1000) { + static int print_once; + policy->cpuinfo.transition_latency = 20 * 1000; + if (!print_once) { + print_once = 1; + printk(KERN_INFO "Capping off P-state tranision latency" + " at 20 uS\n"); + } + } + data->max_freq = perf->states[0].core_frequency * 1000; /* table init */ for (i = 0; i < perf->state_count; i++) { |