diff options
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/Kconfig.x86 | 12 | ||||
| -rw-r--r-- | drivers/cpufreq/acpi-cpufreq.c | 46 |
2 files changed, 56 insertions, 2 deletions
diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86 index b36ca1f68bff..934854ae5eb4 100644 --- a/drivers/cpufreq/Kconfig.x86 +++ b/drivers/cpufreq/Kconfig.x86 @@ -33,6 +33,18 @@ config X86_ACPI_CPUFREQ If in doubt, say N. +config X86_ACPI_CPUFREQ_CPB + default y + bool "Legacy cpb sysfs knob support for AMD CPUs" + depends on X86_ACPI_CPUFREQ && CPU_SUP_AMD + help + The powernow-k8 driver used to provide a sysfs knob called "cpb" + to disable the Core Performance Boosting feature of AMD CPUs. This + file has now been superseeded by the more generic "boost" entry. + + By enabling this option the acpi_cpufreq driver provides the old + entry in addition to the new boost ones, for compatibility reasons. + config ELAN_CPUFREQ tristate "AMD Elan SC400 and SC410" select CPU_FREQ_TABLE diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c index dffa7af1db71..0d048f6a2b23 100644 --- a/drivers/cpufreq/acpi-cpufreq.c +++ b/drivers/cpufreq/acpi-cpufreq.c @@ -133,8 +133,7 @@ static void boost_set_msrs(bool enable, const struct cpumask *cpumask) wrmsr_on_cpus(cpumask, msr_addr, msrs); } -static ssize_t store_global_boost(struct kobject *kobj, struct attribute *attr, - const char *buf, size_t count) +static ssize_t _store_boost(const char *buf, size_t count) { int ret; unsigned long val = 0; @@ -161,6 +160,12 @@ static ssize_t store_global_boost(struct kobject *kobj, struct attribute *attr, return count; } +static ssize_t store_global_boost(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t count) +{ + return _store_boost(buf, count); +} + static ssize_t show_global_boost(struct kobject *kobj, struct attribute *attr, char *buf) { @@ -171,6 +176,21 @@ static struct global_attr global_boost = __ATTR(boost, 0644, show_global_boost, store_global_boost); +#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB +static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf, + size_t count) +{ + return _store_boost(buf, count); +} + +static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf) +{ + return sprintf(buf, "%u\n", boost_enabled); +} + +static struct freq_attr cpb = __ATTR(cpb, 0644, show_cpb, store_cpb); +#endif + static int check_est_cpu(unsigned int cpuid) { struct cpuinfo_x86 *cpu = &cpu_data(cpuid); @@ -889,6 +909,7 @@ static int acpi_cpufreq_resume(struct cpufreq_policy *policy) static struct freq_attr *acpi_cpufreq_attr[] = { &cpufreq_freq_attr_scaling_available_freqs, + NULL, /* this is a placeholder for cpb, do not remove */ NULL, }; @@ -960,6 +981,27 @@ static int __init acpi_cpufreq_init(void) if (ret) return ret; +#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB + /* this is a sysfs file with a strange name and an even stranger + * semantic - per CPU instantiation, but system global effect. + * Lets enable it only on AMD CPUs for compatibility reasons and + * only if configured. This is considered legacy code, which + * will probably be removed at some point in the future. + */ + if (check_amd_hwpstate_cpu(0)) { + struct freq_attr **iter; + + pr_debug("adding sysfs entry for cpb\n"); + + for (iter = acpi_cpufreq_attr; *iter != NULL; iter++) + ; + + /* make sure there is a terminator behind it */ + if (iter[1] == NULL) + *iter = &cpb; + } +#endif + ret = cpufreq_register_driver(&acpi_cpufreq_driver); if (ret) free_acpi_perf_data(); |