// SPDX-License-Identifier: GPL-2.0-or-later
/*
* acpi-cpufreq.c - ACPI Processor P-States Driver
*
* Copyright (C) 2001, 2002 Andy Grover <[email protected]>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
* Copyright (C) 2002 - 2004 Dominik Brodowski <[email protected]>
* Copyright (C) 2006 Denis Sadykov <[email protected]>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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/string_helpers.h>
#include <linux/platform_device.h>
#include <linux/acpi.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <acpi/processor.h>
#include <acpi/cppc_acpi.h>
#include <asm/msr.h>
#include <asm/processor.h>
#include <asm/cpufeature.h>
#include <asm/cpu_device_id.h>
MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
MODULE_DESCRIPTION("ACPI Processor P-States Driver");
MODULE_LICENSE("GPL");
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 HYGON_MSR_RANGE (0x7)
struct acpi_cpufreq_data {
unsigned int resume;
unsigned int cpu_feature;
unsigned int acpi_perf_cpu;
cpumask_var_t freqdomain_cpus;
void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
};
/* 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 bool boost_state(unsigned int cpu)
{
u32 lo, hi;
u64 msr;
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_INTEL:
case X86_VENDOR_CENTAUR:
case X86_VENDOR_ZHAOXIN:
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_HYGON:
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 int boost_set_msr(bool enable)
{
u32 msr_addr;
u64 msr_mask, val;
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_INTEL:
case X86_VENDOR_CENTAUR:
case X86_VENDOR_ZHAOXIN:
msr_addr = MSR_IA32_MISC_ENABLE;
msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
break;
case X86_VENDOR_HYGON:
case X86_VENDOR_AMD:
msr_addr = MSR_K7_HWCR;
msr_mask = MSR_K7_HWCR_CPB_DIS;
break;
default:
return -EINVAL;
}
rdmsrl(msr_addr, val);
if (enable)
val &= ~msr_mask;
else
val |= msr_mask;
wrmsrl(msr_addr, val);
return 0;
}
static void boost_set_msr_each(void *p_en)
{
bool enable = (bool) p_en;
boost_set_msr(enable);
}
static int set_boost(struct cpufreq_policy *policy, int val)
{
on_each_cpu_mask(policy->cpus, boost_set_msr_each,
(void *)(long)val, 1);
pr_debug("CPU %*pbl: Core Boosting %s.\n",
cpumask_pr_args(policy->cpus), str_enabled_disabled(val));
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_cpb(struct cpufreq_policy *policy, const char *buf,
size_t count)
{
int ret;
unsigned int val = 0;
if (!acpi_cpufreq_driver.set_boost)
return -EINVAL;
ret = kstrtouint(buf, 10, &val);
if (ret || val > 1)
return -EINVAL;
cpus_read_lock();
set_boost(policy, val);
cpus_read_unlock();
return count;
}
static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
{
return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
}
cpufreq_freq_attr_rw(cpb);
#endif
static int check_est_cpu(unsigned int cpuid)
{
struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
return cpu_has(cpu, X86_FEATURE_EST);
}
static int check_amd_hwpstate_cpu(unsigned int cpuid)
{
struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
}
static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
{
struct acpi_cpufreq_data *data = policy->driver_data;
struct acpi_processor_performance *perf;
int i;
perf = to_perf_data(data);
for (i = 0; i < perf->state_count; i++) {
if (value == perf->states[i].status)
return policy->freq_table[i].frequency;
}
return 0;
}
static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
{
struct acpi_cpufreq_data *data = policy->driver_data;
struct cpufreq_frequency_table *pos;
struct acpi_processor_performance *perf;
if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
msr &= AMD_MSR_RANGE;
else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
msr &= HYGON_MSR_RANGE;
else
msr &= INTEL_MSR_RANGE;
perf = to_perf_data(data);
cpufreq_for_each_entry(pos, policy->freq_table)
if (msr == perf->states[pos->driver_data].status)
return pos->frequency;
return policy->freq_table[0].frequency;
}
static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
{
struct acpi_cpufreq_data *data = policy->driver_data;
switch (data->cpu_feature) {
case SYSTEM_INTEL_MSR_CAPABLE:
case SYSTEM_AMD_MSR_CAPABLE:
return extract_msr(policy, val);
case SYSTEM_IO_CAPABLE:
return extract_io(policy, val);
default:
return 0;
}
}
static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
{
u32 val, dummy __always_unused;
rdmsr(MSR_IA32_PERF_CTL, val, dummy);
return val;
}
static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
{
u32 lo, hi;
rdmsr(MSR_IA32_PERF_CTL, lo, hi);
lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
wrmsr(MSR_IA32_PERF_CTL, lo, hi);
}
static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
{
u32 val, dummy __always_unused;
rdmsr(MSR_AMD_PERF_CTL, val, dummy);
return val;
}
static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
{
wrmsr(MSR_AMD_PERF_CTL, val, 0);
}
static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
{
u32 val;
acpi_os_read_port(reg->address, &val, reg->bit_width);
return val;
}
static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
{
acpi_os_write_port(reg->address, val, reg->bit_width);
}
struct drv_cmd {
struct acpi_pct_register *reg;
u32 val;
union {
void (*write)(struct acpi_pct_register *reg, u32 val);
u32 (*read)(struct acpi_pct_register *reg);
} func;
};
/* Called via smp_call_function_single(), on the target CPU */
static void do_drv_read(void *_cmd)
{
struct drv_cmd *cmd = _cmd;
cmd->val = cmd->func.read(cmd->reg);
}
static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
{
struct acpi_processor_performance *perf = to_perf_data(data);
struct drv_cmd cmd = {
.reg = &perf->control_register,
.func.read = data->cpu_freq_read,
};
int err;
err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
return cmd.val;
}
/* Called via smp_call_function_many(), on the target CPUs */
static void do_drv_write(void *_cmd)
{
struct drv_cmd *cmd = _cmd;
cmd->func.write(cmd->reg, cmd->val);
}
static void drv_write(struct acpi_cpufreq_data *data,
const struct cpumask *mask, u32 val)
{
struct acpi_processor_performance *perf = to_perf_data(data);
struct drv_cmd cmd = {
.reg = &perf->control_register,
.val = val,
.func.write = data->cpu_freq_write,
};
int this_cpu;
this_cpu = get_cpu();
if (cpumask_test_cpu(this_cpu, mask))
do_drv_write(&cmd);
smp_call_function_many(mask, do_drv_write, &cmd, 1);
put_cpu();
}
static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
{
u32 val;
if (unlikely(cpumask_empty(mask)))
return 0;
val = drv_read(data, mask);
pr_debug("%s = %u\n", __func__, val);
return val;
}
static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
{
struct acpi_cpufreq_data *data;
struct cpufreq_policy *policy;
unsigned int freq;
unsigned int cached_freq;
pr_debug("%s (%d)\n", __func__, cpu);
policy = cpufreq_cpu_get_raw(cpu);
if (unlikely(!policy))
return 0;
data = policy->driver_data;
if (unlikely(!data || !policy->freq_table))
return 0;
cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
if (freq != cached_freq) {
/*
* The dreaded BIOS frequency change behind our back.
* Force set the frequency on next target call.
*/
data->resume = 1;
}
pr_debug("cur freq = %u\n", freq);
return freq;
}
static unsigned int check_freqs(struct cpufreq_policy *policy,
const struct cpumask *mask, unsigned int freq)
{
struct acpi_cpufreq_data *data = policy->driver_data;
unsigned int cur_freq;
unsigned int i;
for (i = 0; i < 100; i++) {
cur_freq = extract_freq(policy, get_cur_val(mask, data));
if (cur_freq == freq)
return 1;
udelay(10);
}
return 0;
}
static int acpi_cpufreq_target(struct cpufreq_policy *policy,
unsigned int index)
{
struct acpi_cpufreq_data *data = policy->driver_data;
struct acpi_processor_performance *perf;
const struct cpumask *mask;
unsigned int next_perf_state = 0; /* Index into perf table */
int result = 0;
if (unlikely(!data)) {
return -ENODEV;
}
perf = to_perf_data(data);
next_perf_state = policy->freq_table[index].driver_data;
if (perf->state == next_perf_state) {
if (unlikely(data->resume)) {
pr_debug("Called after resume, resetting to P%d\n",
next_perf_state);
data->resume = 0;
} else {
pr_debug("Already at target state (P%d)\n",
next_perf_state);
return 0;
}
}
/*
* The core won't allow CPUs to go away until the governor has been
* stopped, so we can rely on the stability of policy->cpus.
*/
mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
cpumask_of(policy->cpu) : policy->cpus;
drv_write(data, mask, perf->states[next_perf_state].control);
if (acpi_pstate_strict) {
if (!check_freqs(policy, mask,
policy->freq_table[index].frequency)) {
pr_debug("%s (%d)\n", __func__, policy->cpu);
result = -EAGAIN;
}
}
if (!result)
perf->state = next_perf_state;
return result;
}
static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
unsigned int target_freq)
{
struct acpi_cpufreq_data *data = policy->driver_data;
struct acpi_processor_performance *perf;
struct cpufreq_frequency_table *entry;
unsigned int next_perf_state, next_freq, index;
/*
* Find the closest frequency above target_freq.
*/
if (policy->cached_target_freq == target_freq)
index = policy->cached_resolved_idx;
else
index = cpufreq_table_find_index_dl(policy, target_freq,
false);
entry = &policy->freq_table[index];
next_freq = entry->frequency;
next_perf_state = entry->driver_data;
perf = to_perf_data(data);
if (perf->state == next_perf_state) {
if (unlikely(data->resume))
data->resume = 0;
else
return next_freq;
}
data->cpu_freq_write(&perf->control_register,
perf->states[next_perf_state].control);
perf->state = next_perf_state;
return next_freq;
}
static unsigned long
acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
{
struct acpi_processor_performance *perf;
perf = to_perf_data(data);
if (cpu_khz) {
/* search the closest match to cpu_khz */
unsigned int i;
unsigned long freq;
unsigned long freqn = perf->states[0].core_frequency * 1000;
for (i = 0; i < (perf->state_count-1); i++) {
freq = freqn;
freqn = perf->states[i+1].core_frequency * 1000;
if ((2 * cpu_khz) > (freqn + freq)) {
perf->state = i;
return freq;
}
}
perf->state = perf->state_count-1;
return freqn;
} else {
/* assume CPU is at P0... */
perf->state = 0;
return perf->states[0].core_frequency * 1000;
}
}
static void free_acpi_perf_data(void)
{
unsigned int i;
/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
for_each_possible_cpu(i)
free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
->shared_cpu_map);
free_percpu(acpi_perf_data);
}
static int cpufreq_boost_down_prep(unsigned int cpu)
{
/*
* Clear the boost-disable bit on the CPU_DOWN path so that
* this cpu cannot block the remaining ones from boosting.
*/
return boost_set_msr(1);
}
/*
* acpi_cpufreq_early_init - initialize ACPI P-States library
*
* Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
* in order to determine correct frequency and voltage pairings. We can
* do _PDC and _PSD and find out the processor dependency for the
* actual init that will happen later...
*/
static int __init acpi_cpufreq_early_init(void)
{
unsigned int i;
pr_debug("%s\n", __func__);
acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
if (!acpi_perf_data) {
pr_debug("Memory allocation error for acpi_perf_data.\n");
return -ENOMEM;
}
for_each_possible_cpu(i) {
if (!zalloc_cpumask_var_node(
&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
GFP_KERNEL, cpu_to_node(i))) {
/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
free_acpi_perf_data();
return -ENOMEM;
}
}
/* Do initialization in ACPI core */
acpi_processor_preregister_performance(acpi_perf_data);
return 0;
}
#ifdef CONFIG_SMP
/*
* Some BIOSes do SW_ANY coordination internally, either set it up in hw
* or do it in BIOS firmware and won't inform about it to OS. If not
* detected, this has a side effect of making CPU run at a different speed
* than OS intended it to run at. Detect it and handle it cleanly.
*/
static int bios_with_sw_any_bug;
static int sw_any_bug_found(const struct dmi_system_id *d)
{
bios_with_sw_any_bug = 1;
return 0;
}
static const struct dmi_system_id sw_any_bug_dmi_table[] = {
{
.callback = sw_any_bug_found,
.ident = "Supermicro Server X6DLP",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
DMI_MATCH(DMI_BIOS_VERSION, "080010"),
DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
},
},
{ }
};
static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
{
/* Intel Xeon Processor 7100 Series Specification Update
* https://www.intel.com/Assets/PDF/specupdate/314554.pdf
* AL30: A Machine Check Exception (MCE) Occurring during an
* Enhanced Intel SpeedStep Technology Ratio Change May Cause
* Both Processor Cores to Lock Up. */
if (c->x86_vendor == X86_VENDOR_INTEL) {
if ((c->x86 == 15) &&
(c->x86_model == 6) &&
(c->x86_stepping == 8)) {
pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
return -ENODEV;
}
}
return 0;
}
#endif
#ifdef CONFIG_ACPI_CPPC_LIB
static u64 get_max_boost_ratio(unsigned int cpu)
{
struct cppc_perf_caps perf_caps;
u64 highest_perf, nominal_perf;
int ret;
if (acpi_pstate_strict)
return 0;
ret = cppc_get_perf_caps(cpu, &perf_caps);
if (ret) {
pr_debug("CPU%d: Unable to get performance capabilities (%d)\n",
cpu, ret);
return 0;
}
if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
ret = amd_get_boost_ratio_numerator(cpu, &highest_perf);
if (ret) {
pr_debug("CPU%d: Unable to get boost ratio numerator (%d)\n",
cpu, ret);
return 0;
}
} else {
highest_perf = perf_caps.highest_perf;
}
nominal_perf = perf_caps.nominal_perf;
if (!highest_perf || !nominal_perf) {
pr_debug("CPU%d: highest or nominal performance missing\n", cpu);
return 0;
}
if (highest_perf < nominal_perf) {
pr_debug("CPU%d: nominal performance above highest\n", cpu);
return 0;
}
return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf);
}
#else
static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; }
#endif
static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
struct cpufreq_frequency_table *freq_table;
struct acpi_processor_performance *perf;
struct acpi_cpufreq_data *data;
unsigned int cpu = policy->cpu;
struct cpuinfo_x86 *c = &cpu_data(cpu);
unsigned int valid_states = 0;
unsigned int result = 0;
u64 max_boost_ratio;
unsigned int i;
#ifdef CONFIG_SMP
static int blacklisted;
#endif
pr_debug("%s\n", __func__);
#ifdef CONFIG_SMP
if (blacklisted)
return blacklisted;
blacklisted = acpi_cpufreq_blacklist(c);
if (blacklisted)
return blacklisted;
#endif
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
result = -ENOMEM;
goto err_free;
}
perf = per_cpu_ptr(acpi_perf_data, cpu);
data->acpi_perf_cpu = cpu;
policy->driver_data = data;
if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
result = acpi_processor_register_performance(perf, cpu);
if (result)
goto err_free_mask;
policy->shared_type = perf->shared_type;
/*
* Will let policy->cpus know about dependency only when software
* coordination is required.
*/
if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
cpumask_copy(policy->cpus, perf->shared_cpu_map);
}
cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
#ifdef CONFIG_SMP
dmi_check_system(sw_any_bug_dmi_table);
if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
}
if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&
!acpi_pstate_strict) {
cpumask_clear(policy->cpus);
cpumask_set_cpu(cpu, policy->cpus);
cpumask_copy(data->freqdomain_cpus,
topology_sibling_cpumask(cpu));
policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
pr_info_once("overriding BIOS provided _PSD data\n");
}
#endif
/* capability check */
if (perf->state_count <= 1) {
pr_debug("No P-States\n");
result = -ENODEV;
goto err_unreg;
}
if (perf->control_register.space_id != perf->status_register.space_id) {
result = -ENODEV;
goto err_unreg;
}
switch (perf->control_register.space_id) {
case ACPI_ADR_SPACE_SYSTEM_IO:
if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
boot_cpu_data.x86 == 0xf) {
pr_debug("AMD K8 systems must use native drivers.\n");
result = -ENODEV;
goto err_unreg;
}
pr_debug("SYSTEM IO addr space\n");
data->cpu_feature = SYSTEM_IO_CAPABLE;
data->cpu_freq_read = cpu_freq_read_io;
data->cpu_freq_write = cpu_freq_write_io;
break;
case ACPI_ADR_SPACE_FIXED_HARDWARE:
pr_debug("HARDWARE addr space\n");
if (check_est_cpu(cpu)) {
data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
data->cpu_freq_read = cpu_freq_read_intel;
data->cpu_freq_write = cpu_freq_write_intel;
break;
}
if (check_amd_hwpstate_cpu(cpu)) {
data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
data->cpu_freq_read = cpu_freq_read_amd;
data->cpu_freq_write = cpu_freq_write_amd;
break;
}
result = -ENODEV;
goto err_unreg;
default:
pr_debug("Unknown addr space %d\n",
(u32) (perf->control_register.space_id));
result = -ENODEV;
goto err_unreg;
}
freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
GFP_KERNEL);
if (!freq_table) {
result = -ENOMEM;
goto err_unreg;
}
/* detect transition latency */
policy->cpuinfo.transition_latency = 0;
for (i = 0; i < perf->state_count; i++) {
if ((perf->states[i].transition_latency * 1000) >
policy->cpuinfo.transition_latency)
policy->cpuinfo.transition_latency =
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) {
policy->cpuinfo.transition_latency = 20 * 1000;
pr_info_once("P-state transition latency capped at 20 uS\n");
}
/* table init */
for (i = 0; i < perf->state_count; i++) {
if (i > 0 && perf->states[i].core_frequency >=
freq_table[valid_states-1].frequency / 1000)
continue;
freq_table[valid_states].driver_data = i;
freq_table[valid_states].frequency =
perf->states[i].core_frequency * 1000;
valid_states++;
}
freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
max_boost_ratio = get_max_boost_ratio(cpu);
if (max_boost_ratio) {
unsigned int freq = freq_table[0].frequency;
/*
* Because the loop above sorts the freq_table entries in the
* descending order, freq is the maximum frequency in the table.
* Assume that it corresponds to the CPPC nominal frequency and
* use it to set cpuinfo.max_freq.
*/
policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT;
} else {
/*
* If the maximum "boost" frequency is unknown, ask the arch
* scale-invariance code to use the "nominal" performance for
* CPU utilization scaling so as to prevent the schedutil
* governor from selecting inadequate CPU frequencies.
*/
arch_set_max_freq_ratio(true);
}
policy->freq_table = freq_table;
perf->state = 0;
switch (perf->control_register.space_id) {
case ACPI_ADR_SPACE_SYSTEM_IO:
/*
* The core will not set policy->cur, because
* cpufreq_driver->get is NULL, so we need to set it here.
* However, we have to guess it, because the current speed is
* unknown and not detectable via IO ports.
*/
policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
break;
case ACPI_ADR_SPACE_FIXED_HARDWARE:
acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
break;
default:
break;
}
/* notify BIOS that we exist */
acpi_processor_notify_smm(THIS_MODULE);
pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
for (i = 0; i < perf->state_count; i++)
pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
(i == perf->state ? '*' : ' '), i,
(u32) perf->states[i].core_frequency,
(u32) perf->states[i].power,
(u32) perf->states[i].transition_latency);
/*
* the first call to ->target() should result in us actually
* writing something to the appropriate registers.
*/
data->resume = 1;
policy->fast_switch_possible = !acpi_pstate_strict &&
!(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency)
pr_warn(FW_WARN "P-state 0 is not max freq\n");
if (acpi_cpufreq_driver.set_boost) {
set_boost(policy, acpi_cpufreq_driver.boost_enabled);
policy->boost_enabled = acpi_cpufreq_driver.boost_enabled;
}
return result;
err_unreg:
acpi_processor_unregister_performance(cpu);
err_free_mask:
free_cpumask_var(data->freqdomain_cpus);
err_free:
kfree(data);
policy->driver_data = NULL;
return result;
}
static void acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
{
struct acpi_cpufreq_data *data = policy->driver_data;
pr_debug("%s\n", __func__);
cpufreq_boost_down_prep(policy->cpu);
policy->fast_switch_possible = false;
policy->driver_data = NULL;
acpi_processor_unregister_performance(data->acpi_perf_cpu);
free_cpumask_var(data->freqdomain_cpus);
kfree(policy->freq_table);
kfree(data);
}
static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
{
struct acpi_cpufreq_data *data = policy->driver_data;
pr_debug("%s\n", __func__);
data->resume = 1;
return 0;
}
static struct freq_attr *acpi_cpufreq_attr[] = {
&cpufreq_freq_attr_scaling_available_freqs,
&freqdomain_cpus,
#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
&cpb,
#endif
NULL,
};
static struct cpufreq_driver acpi_cpufreq_driver = {
.verify = cpufreq_generic_frequency_table_verify,
.target_index = acpi_cpufreq_target,
.fast_switch = acpi_cpufreq_fast_switch,
.bios_limit = acpi_processor_get_bios_limit,
.init = acpi_cpufreq_cpu_init,
.exit = acpi_cpufreq_cpu_exit,
.resume = acpi_cpufreq_resume,
.name = "acpi-cpufreq",
.attr = acpi_cpufreq_attr,
};
static void __init acpi_cpufreq_boost_init(void)
{
if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
pr_debug("Boost capabilities not present in the processor\n");
return;
}
acpi_cpufreq_driver.set_boost = set_boost;
acpi_cpufreq_driver.boost_enabled = boost_state(0);
}
static int __init acpi_cpufreq_probe(struct platform_device *pdev)
{
int ret;
if (acpi_disabled)
return -ENODEV;
/* don't keep reloading if cpufreq_driver exists */
if (cpufreq_get_current_driver())
return -ENODEV;
pr_debug("%s\n", __func__);
ret = acpi_cpufreq_early_init();
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 **attr;
pr_debug("CPB unsupported, do not expose it\n");
for (attr = acpi_cpufreq_attr; *attr; attr++)
if (*attr == &cpb) {
*attr = NULL;
break;
}
}
#endif
acpi_cpufreq_boost_init();
ret = cpufreq_register_driver(&acpi_cpufreq_driver);
if (ret) {
free_acpi_perf_data();
}
return ret;
}
static void acpi_cpufreq_remove(struct platform_device *pdev)
{
pr_debug("%s\n", __func__);
cpufreq_unregister_driver(&acpi_cpufreq_driver);
free_acpi_perf_data();
}
static struct platform_driver acpi_cpufreq_platdrv = {
.driver = {
.name = "acpi-cpufreq",
},
.remove_new = acpi_cpufreq_remove,
};
static int __init acpi_cpufreq_init(void)
{
return platform_driver_probe(&acpi_cpufreq_platdrv, acpi_cpufreq_probe);
}
static void __exit acpi_cpufreq_exit(void)
{
platform_driver_unregister(&acpi_cpufreq_platdrv);
}
module_param(acpi_pstate_strict, uint, 0644);
MODULE_PARM_DESC(acpi_pstate_strict,
"value 0 or non-zero. non-zero -> strict ACPI checks are "
"performed during frequency changes.");
late_initcall(acpi_cpufreq_init);
module_exit(acpi_cpufreq_exit);
MODULE_ALIAS("platform:acpi-cpufreq");
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