/*
* acpi-cpufreq.c - ACPI Processor P-States Driver
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
* Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
* Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/sched.h>
#include <linux/cpufreq.h>
#include <linux/compiler.h>
#include <linux/dmi.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <acpi/processor.h>
#include <asm/msr.h>
#include <asm/processor.h>
#include <asm/cpufeature.h>
MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
MODULE_DESCRIPTION("ACPI Processor P-States Driver");
MODULE_LICENSE("GPL");
#define PFX "acpi-cpufreq: "
enum {
UNDEFINED_CAPABLE = 0,
SYSTEM_INTEL_MSR_CAPABLE,
SYSTEM_AMD_MSR_CAPABLE,
SYSTEM_IO_CAPABLE,
};
#define INTEL_MSR_RANGE (0xffff)
#define AMD_MSR_RANGE (0x7)
#define MSR_K7_HWCR_CPB_DIS (1ULL << 25)
struct acpi_cpufreq_data {
struct cpufreq_frequency_table *freq_table;
unsigned int resume;
unsigned int cpu_feature;
unsigned int acpi_perf_cpu;
cpumask_var_t freqdomain_cpus;
};
/* acpi_perf_data is a pointer to percpu data. */
static struct acpi_processor_performance __percpu *acpi_perf_data;
static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
{
return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
}
static struct cpufreq_driver acpi_cpufreq_driver;
static unsigned int acpi_pstate_strict;
static struct msr __percpu *msrs;
static bool boost_state(unsigned int cpu)
{
u32 lo, hi;
u64 msr;
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_INTEL:
rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
msr = lo | ((u64)hi << 32);
return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
case X86_VENDOR_AMD:
rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
msr = lo | ((u64)hi << 32);
return !(msr & MSR_K7_HWCR_CPB_DIS);
}
return false;
}
static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
{
u32 cpu;
u32 msr_addr;
u64 msr_mask;
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_INTEL:
msr_addr = MSR_IA32_MISC_ENABLE;
msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
break;
case X86_VENDOR_AMD:
msr_addr = MSR_K7_HWCR;
msr_mask = MSR_K7_HWCR_CPB_DIS;
break;
default:
return;
}
rdmsr_on_cpus(cpumask, msr_addr, msrs);
for_each_cpu(cpu, cpumask) {
struct msr *reg = per_cpu_ptr(msrs, cpu);
if (enable)
reg->q &= ~msr_mask;
else
reg->q |= msr_mask;
}
wrmsr_on_cpus(cpumask, msr_addr, msrs);
}
static int _store_boost(int val)
{
get_online_cpus();
boost_set_msrs(val, cpu_online_mask);
put_online_cpus();
pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
return 0;
}
static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
{
struct acpi_cpufreq_data *data = policy->driver_data;
if (unlikely(!data))
return -ENODEV;
return cpufreq_show_cpus(data->freqdomain_cpus, buf);
}
cpufreq_freq_attr_ro(freqdomain_cpus);
#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
static ssize_t store_boost(const char *buf, size_t count)
{
int ret;
unsigned long val = 0;
if (!acpi_cpufreq_driver.boost_supported)
return -EINVAL;
ret = kstrtoul(buf, 10, &val);
if (ret || (val > 1))
return -EINVAL;
_store_boost((int)