diff options
Diffstat (limited to 'drivers/cpufreq/cppc_cpufreq.c')
| -rw-r--r-- | drivers/cpufreq/cppc_cpufreq.c | 68 |
1 files changed, 57 insertions, 11 deletions
diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 8882b8e2ecd0..1b2f28f69a81 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -19,10 +19,19 @@ #include <linux/delay.h> #include <linux/cpu.h> #include <linux/cpufreq.h> +#include <linux/dmi.h> #include <linux/vmalloc.h> +#include <asm/unaligned.h> + #include <acpi/cppc_acpi.h> +/* Minimum struct length needed for the DMI processor entry we want */ +#define DMI_ENTRY_PROCESSOR_MIN_LENGTH 48 + +/* Offest in the DMI processor structure for the max frequency */ +#define DMI_PROCESSOR_MAX_SPEED 0x14 + /* * These structs contain information parsed from per CPU * ACPI _CPC structures. @@ -30,19 +39,52 @@ * performance capabilities, desired performance level * requested etc. */ -static struct cpudata **all_cpu_data; +static struct cppc_cpudata **all_cpu_data; + +/* Capture the max KHz from DMI */ +static u64 cppc_dmi_max_khz; + +/* Callback function used to retrieve the max frequency from DMI */ +static void cppc_find_dmi_mhz(const struct dmi_header *dm, void *private) +{ + const u8 *dmi_data = (const u8 *)dm; + u16 *mhz = (u16 *)private; + + if (dm->type == DMI_ENTRY_PROCESSOR && + dm->length >= DMI_ENTRY_PROCESSOR_MIN_LENGTH) { + u16 val = (u16)get_unaligned((const u16 *) + (dmi_data + DMI_PROCESSOR_MAX_SPEED)); + *mhz = val > *mhz ? val : *mhz; + } +} + +/* Look up the max frequency in DMI */ +static u64 cppc_get_dmi_max_khz(void) +{ + u16 mhz = 0; + + dmi_walk(cppc_find_dmi_mhz, &mhz); + + /* + * Real stupid fallback value, just in case there is no + * actual value set. + */ + mhz = mhz ? mhz : 1; + + return (1000 * mhz); +} static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) { - struct cpudata *cpu; + struct cppc_cpudata *cpu; struct cpufreq_freqs freqs; int ret = 0; cpu = all_cpu_data[policy->cpu]; - cpu->perf_ctrls.desired_perf = target_freq; + cpu->perf_ctrls.desired_perf = (u64)target_freq * policy->max / cppc_dmi_max_khz; freqs.old = policy->cur; freqs.new = target_freq; @@ -66,7 +108,7 @@ static int cppc_verify_policy(struct cpufreq_policy *policy) static void cppc_cpufreq_stop_cpu(struct cpufreq_policy *policy) { int cpu_num = policy->cpu; - struct cpudata *cpu = all_cpu_data[cpu_num]; + struct cppc_cpudata *cpu = all_cpu_data[cpu_num]; int ret; cpu->perf_ctrls.desired_perf = cpu->perf_caps.lowest_perf; @@ -79,7 +121,7 @@ static void cppc_cpufreq_stop_cpu(struct cpufreq_policy *policy) static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) { - struct cpudata *cpu; + struct cppc_cpudata *cpu; unsigned int cpu_num = policy->cpu; int ret = 0; @@ -94,10 +136,13 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) return ret; } - policy->min = cpu->perf_caps.lowest_perf; - policy->max = cpu->perf_caps.highest_perf; + cppc_dmi_max_khz = cppc_get_dmi_max_khz(); + + policy->min = cpu->perf_caps.lowest_perf * cppc_dmi_max_khz / cpu->perf_caps.highest_perf; + policy->max = cppc_dmi_max_khz; policy->cpuinfo.min_freq = policy->min; policy->cpuinfo.max_freq = policy->max; + policy->cpuinfo.transition_latency = cppc_get_transition_latency(cpu_num); policy->shared_type = cpu->shared_type; if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) @@ -112,7 +157,8 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) cpu->cur_policy = policy; /* Set policy->cur to max now. The governors will adjust later. */ - policy->cur = cpu->perf_ctrls.desired_perf = cpu->perf_caps.highest_perf; + policy->cur = cppc_dmi_max_khz; + cpu->perf_ctrls.desired_perf = cpu->perf_caps.highest_perf; ret = cppc_set_perf(cpu_num, &cpu->perf_ctrls); if (ret) @@ -134,7 +180,7 @@ static struct cpufreq_driver cppc_cpufreq_driver = { static int __init cppc_cpufreq_init(void) { int i, ret = 0; - struct cpudata *cpu; + struct cppc_cpudata *cpu; if (acpi_disabled) return -ENODEV; @@ -144,7 +190,7 @@ static int __init cppc_cpufreq_init(void) return -ENOMEM; for_each_possible_cpu(i) { - all_cpu_data[i] = kzalloc(sizeof(struct cpudata), GFP_KERNEL); + all_cpu_data[i] = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL); if (!all_cpu_data[i]) goto out; @@ -175,7 +221,7 @@ out: static void __exit cppc_cpufreq_exit(void) { - struct cpudata *cpu; + struct cppc_cpudata *cpu; int i; cpufreq_unregister_driver(&cppc_cpufreq_driver); |