![Dominik Brodowski](/assets/img/avatar_default.png)
With dynamic debug having gained the capability to report debug messages also during the boot process, it offers a far superior interface for debug messages than the custom cpufreq infrastructure. As a first step, remove the old cpufreq_debug_printk() function and replace it with a call to the generic pr_debug() function. How can dynamic debug be used on cpufreq? You need a kernel which has CONFIG_DYNAMIC_DEBUG enabled. To enabled debugging during runtime, mount debugfs and $ echo -n 'module cpufreq +p' > /sys/kernel/debug/dynamic_debug/control for debugging the complete "cpufreq" module. To achieve the same goal during boot, append ddebug_query="module cpufreq +p" as a boot parameter to the kernel of your choice. For more detailled instructions, please see Documentation/dynamic-debug-howto.txt Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Dave Jones <davej@redhat.com>
438 lines
9.8 KiB
C
438 lines
9.8 KiB
C
/*
|
|
* arch/ia64/kernel/cpufreq/acpi-cpufreq.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,
|
|
unsigned int cpu,
|
|
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(cpu));
|
|
if (smp_processor_id() != 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.cpu = cpu;
|
|
cpufreq_freqs.old = data->freq_table[data->acpi_data.state].frequency;
|
|
cpufreq_freqs.new = data->freq_table[state].frequency;
|
|
|
|
/* notify cpufreq */
|
|
cpufreq_notify_transition(&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(&cpufreq_freqs, CPUFREQ_POSTCHANGE);
|
|
cpufreq_freqs.new = cpufreq_freqs.old;
|
|
cpufreq_freqs.old = tmp;
|
|
cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_PRECHANGE);
|
|
cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE);
|
|
printk(KERN_WARNING "Transition failed with error %d\n", ret);
|
|
retval = -ENODEV;
|
|
goto migrate_end;
|
|
}
|
|
|
|
cpufreq_notify_transition(&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->cpu, 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].index = 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);
|
|
|