linux/drivers/cpufreq/ia64-acpi-cpufreq.c
Viresh Kumar 5070158804 cpufreq: rename index as driver_data in cpufreq_frequency_table
The "index" field of struct cpufreq_frequency_table was never an
index and isn't used at all by the cpufreq core.  It only is useful
for cpufreq drivers for their internal purposes.

Many people nowadays blindly set it in ascending order with the
assumption that the core will use it, which is a mistake.

Rename it to "driver_data" as that's what its purpose is. All of its
users are updated accordingly.

[rjw: Changelog]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-04 14:25:59 +02:00

439 lines
9.8 KiB
C

/*
* This file provides the ACPI based P-state support. This
* module works with generic cpufreq infrastructure. Most of
* the code is based on i386 version
* (arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c)
*
* Copyright (C) 2005 Intel Corp
* Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/pal.h>
#include <linux/acpi.h>
#include <acpi/processor.h>
MODULE_AUTHOR("Venkatesh Pallipadi");
MODULE_DESCRIPTION("ACPI Processor P-States Driver");
MODULE_LICENSE("GPL");
struct cpufreq_acpi_io {
struct acpi_processor_performance acpi_data;
struct cpufreq_frequency_table *freq_table;
unsigned int resume;
};
static struct cpufreq_acpi_io *acpi_io_data[NR_CPUS];
static struct cpufreq_driver acpi_cpufreq_driver;
static int
processor_set_pstate (
u32 value)
{
s64 retval;
pr_debug("processor_set_pstate\n");
retval = ia64_pal_set_pstate((u64)value);
if (retval) {
pr_debug("Failed to set freq to 0x%x, with error 0x%lx\n",
value, retval);
return -ENODEV;
}
return (int)retval;
}
static int
processor_get_pstate (
u32 *value)
{
u64 pstate_index = 0;
s64 retval;
pr_debug("processor_get_pstate\n");
retval = ia64_pal_get_pstate(&pstate_index,
PAL_GET_PSTATE_TYPE_INSTANT);
*value = (u32) pstate_index;
if (retval)
pr_debug("Failed to get current freq with "
"error 0x%lx, idx 0x%x\n", retval, *value);
return (int)retval;
}
/* To be used only after data->acpi_data is initialized */
static unsigned
extract_clock (
struct cpufreq_acpi_io *data,
unsigned value,
unsigned int cpu)
{
unsigned long i;
pr_debug("extract_clock\n");
for (i = 0; i < data->acpi_data.state_count; i++) {
if (value == data->acpi_data.states[i].status)
return data->acpi_data.states[i].core_frequency;
}
return data->acpi_data.states[i-1].core_frequency;
}
static unsigned int
processor_get_freq (
struct cpufreq_acpi_io *data,
unsigned int cpu)
{
int ret = 0;
u32 value = 0;
cpumask_t saved_mask;
unsigned long clock_freq;
pr_debug("processor_get_freq\n");
saved_mask = current->cpus_allowed;
set_cpus_allowed_ptr(current, cpumask_of(cpu));
if (smp_processor_id() != cpu)
goto migrate_end;
/* processor_get_pstate gets the instantaneous frequency */
ret = processor_get_pstate(&value);
if (ret) {
set_cpus_allowed_ptr(current, &saved_mask);
printk(KERN_WARNING "get performance failed with error %d\n",
ret);
ret = 0;
goto migrate_end;
}
clock_freq = extract_clock(data, value, cpu);
ret = (clock_freq*1000);
migrate_end:
set_cpus_allowed_ptr(current, &saved_mask);
return ret;
}
static int
processor_set_freq (
struct cpufreq_acpi_io *data,
struct cpufreq_policy *policy,
int state)
{
int ret = 0;
u32 value = 0;
struct cpufreq_freqs cpufreq_freqs;
cpumask_t saved_mask;
int retval;
pr_debug("processor_set_freq\n");
saved_mask = current->cpus_allowed;
set_cpus_allowed_ptr(current, cpumask_of(policy->cpu));
if (smp_processor_id() != policy->cpu) {
retval = -EAGAIN;
goto migrate_end;
}
if (state == data->acpi_data.state) {
if (unlikely(data->resume)) {
pr_debug("Called after resume, resetting to P%d\n", state);
data->resume = 0;
} else {
pr_debug("Already at target state (P%d)\n", state);
retval = 0;
goto migrate_end;
}
}
pr_debug("Transitioning from P%d to P%d\n",
data->acpi_data.state, state);
/* cpufreq frequency struct */
cpufreq_freqs.old = data->freq_table[data->acpi_data.state].frequency;
cpufreq_freqs.new = data->freq_table[state].frequency;
/* notify cpufreq */
cpufreq_notify_transition(policy, &cpufreq_freqs, CPUFREQ_PRECHANGE);
/*
* First we write the target state's 'control' value to the
* control_register.
*/
value = (u32) data->acpi_data.states[state].control;
pr_debug("Transitioning to state: 0x%08x\n", value);
ret = processor_set_pstate(value);
if (ret) {
unsigned int tmp = cpufreq_freqs.new;
cpufreq_notify_transition(policy, &cpufreq_freqs,
CPUFREQ_POSTCHANGE);
cpufreq_freqs.new = cpufreq_freqs.old;
cpufreq_freqs.old = tmp;
cpufreq_notify_transition(policy, &cpufreq_freqs,
CPUFREQ_PRECHANGE);
cpufreq_notify_transition(policy, &cpufreq_freqs,
CPUFREQ_POSTCHANGE);
printk(KERN_WARNING "Transition failed with error %d\n", ret);
retval = -ENODEV;
goto migrate_end;
}
cpufreq_notify_transition(policy, &cpufreq_freqs, CPUFREQ_POSTCHANGE);
data->acpi_data.state = state;
retval = 0;
migrate_end:
set_cpus_allowed_ptr(current, &saved_mask);
return (retval);
}
static unsigned int
acpi_cpufreq_get (
unsigned int cpu)
{
struct cpufreq_acpi_io *data = acpi_io_data[cpu];
pr_debug("acpi_cpufreq_get\n");
return processor_get_freq(data, cpu);
}
static int
acpi_cpufreq_target (
struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu];
unsigned int next_state = 0;
unsigned int result = 0;
pr_debug("acpi_cpufreq_setpolicy\n");
result = cpufreq_frequency_table_target(policy,
data->freq_table, target_freq, relation, &next_state);
if (result)
return (result);
result = processor_set_freq(data, policy, next_state);
return (result);
}
static int
acpi_cpufreq_verify (
struct cpufreq_policy *policy)
{
unsigned int result = 0;
struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu];
pr_debug("acpi_cpufreq_verify\n");
result = cpufreq_frequency_table_verify(policy,
data->freq_table);
return (result);
}
static int
acpi_cpufreq_cpu_init (
struct cpufreq_policy *policy)
{
unsigned int i;
unsigned int cpu = policy->cpu;
struct cpufreq_acpi_io *data;
unsigned int result = 0;
pr_debug("acpi_cpufreq_cpu_init\n");
data = kzalloc(sizeof(struct cpufreq_acpi_io), GFP_KERNEL);
if (!data)
return (-ENOMEM);
acpi_io_data[cpu] = data;
result = acpi_processor_register_performance(&data->acpi_data, cpu);
if (result)
goto err_free;
/* capability check */
if (data->acpi_data.state_count <= 1) {
pr_debug("No P-States\n");
result = -ENODEV;
goto err_unreg;
}
if ((data->acpi_data.control_register.space_id !=
ACPI_ADR_SPACE_FIXED_HARDWARE) ||
(data->acpi_data.status_register.space_id !=
ACPI_ADR_SPACE_FIXED_HARDWARE)) {
pr_debug("Unsupported address space [%d, %d]\n",
(u32) (data->acpi_data.control_register.space_id),
(u32) (data->acpi_data.status_register.space_id));
result = -ENODEV;
goto err_unreg;
}
/* alloc freq_table */
data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
(data->acpi_data.state_count + 1),
GFP_KERNEL);
if (!data->freq_table) {
result = -ENOMEM;
goto err_unreg;
}
/* detect transition latency */
policy->cpuinfo.transition_latency = 0;
for (i=0; i<data->acpi_data.state_count; i++) {
if ((data->acpi_data.states[i].transition_latency * 1000) >
policy->cpuinfo.transition_latency) {
policy->cpuinfo.transition_latency =
data->acpi_data.states[i].transition_latency * 1000;
}
}
policy->cur = processor_get_freq(data, policy->cpu);
/* table init */
for (i = 0; i <= data->acpi_data.state_count; i++)
{
data->freq_table[i].driver_data = i;
if (i < data->acpi_data.state_count) {
data->freq_table[i].frequency =
data->acpi_data.states[i].core_frequency * 1000;
} else {
data->freq_table[i].frequency = CPUFREQ_TABLE_END;
}
}
result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
if (result) {
goto err_freqfree;
}
/* notify BIOS that we exist */
acpi_processor_notify_smm(THIS_MODULE);
printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management "
"activated.\n", cpu);
for (i = 0; i < data->acpi_data.state_count; i++)
pr_debug(" %cP%d: %d MHz, %d mW, %d uS, %d uS, 0x%x 0x%x\n",
(i == data->acpi_data.state?'*':' '), i,
(u32) data->acpi_data.states[i].core_frequency,
(u32) data->acpi_data.states[i].power,
(u32) data->acpi_data.states[i].transition_latency,
(u32) data->acpi_data.states[i].bus_master_latency,
(u32) data->acpi_data.states[i].status,
(u32) data->acpi_data.states[i].control);
cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
/* the first call to ->target() should result in us actually
* writing something to the appropriate registers. */
data->resume = 1;
return (result);
err_freqfree:
kfree(data->freq_table);
err_unreg:
acpi_processor_unregister_performance(&data->acpi_data, cpu);
err_free:
kfree(data);
acpi_io_data[cpu] = NULL;
return (result);
}
static int
acpi_cpufreq_cpu_exit (
struct cpufreq_policy *policy)
{
struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu];
pr_debug("acpi_cpufreq_cpu_exit\n");
if (data) {
cpufreq_frequency_table_put_attr(policy->cpu);
acpi_io_data[policy->cpu] = NULL;
acpi_processor_unregister_performance(&data->acpi_data,
policy->cpu);
kfree(data);
}
return (0);
}
static struct freq_attr* acpi_cpufreq_attr[] = {
&cpufreq_freq_attr_scaling_available_freqs,
NULL,
};
static struct cpufreq_driver acpi_cpufreq_driver = {
.verify = acpi_cpufreq_verify,
.target = acpi_cpufreq_target,
.get = acpi_cpufreq_get,
.init = acpi_cpufreq_cpu_init,
.exit = acpi_cpufreq_cpu_exit,
.name = "acpi-cpufreq",
.owner = THIS_MODULE,
.attr = acpi_cpufreq_attr,
};
static int __init
acpi_cpufreq_init (void)
{
pr_debug("acpi_cpufreq_init\n");
return cpufreq_register_driver(&acpi_cpufreq_driver);
}
static void __exit
acpi_cpufreq_exit (void)
{
pr_debug("acpi_cpufreq_exit\n");
cpufreq_unregister_driver(&acpi_cpufreq_driver);
return;
}
late_initcall(acpi_cpufreq_init);
module_exit(acpi_cpufreq_exit);