266 lines
6.6 KiB
C
266 lines
6.6 KiB
C
/*
|
|
* This file was based upon code in Powertweak Linux (http://powertweak.sf.net)
|
|
* (C) 2000-2003 Dave Jones, Arjan van de Ven, Janne Pänkälä,
|
|
* Dominik Brodowski.
|
|
*
|
|
* Licensed under the terms of the GNU GPL License version 2.
|
|
*
|
|
* BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/cpufreq.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/timex.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <asm/cpu_device_id.h>
|
|
#include <asm/msr.h>
|
|
|
|
#define POWERNOW_IOPORT 0xfff0 /* it doesn't matter where, as long
|
|
as it is unused */
|
|
|
|
#define PFX "powernow-k6: "
|
|
static unsigned int busfreq; /* FSB, in 10 kHz */
|
|
static unsigned int max_multiplier;
|
|
|
|
|
|
/* Clock ratio multiplied by 10 - see table 27 in AMD#23446 */
|
|
static struct cpufreq_frequency_table clock_ratio[] = {
|
|
{45, /* 000 -> 4.5x */ 0},
|
|
{50, /* 001 -> 5.0x */ 0},
|
|
{40, /* 010 -> 4.0x */ 0},
|
|
{55, /* 011 -> 5.5x */ 0},
|
|
{20, /* 100 -> 2.0x */ 0},
|
|
{30, /* 101 -> 3.0x */ 0},
|
|
{60, /* 110 -> 6.0x */ 0},
|
|
{35, /* 111 -> 3.5x */ 0},
|
|
{0, CPUFREQ_TABLE_END}
|
|
};
|
|
|
|
|
|
/**
|
|
* powernow_k6_get_cpu_multiplier - returns the current FSB multiplier
|
|
*
|
|
* Returns the current setting of the frequency multiplier. Core clock
|
|
* speed is frequency of the Front-Side Bus multiplied with this value.
|
|
*/
|
|
static int powernow_k6_get_cpu_multiplier(void)
|
|
{
|
|
u64 invalue = 0;
|
|
u32 msrval;
|
|
|
|
msrval = POWERNOW_IOPORT + 0x1;
|
|
wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */
|
|
invalue = inl(POWERNOW_IOPORT + 0x8);
|
|
msrval = POWERNOW_IOPORT + 0x0;
|
|
wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */
|
|
|
|
return clock_ratio[(invalue >> 5)&7].index;
|
|
}
|
|
|
|
|
|
/**
|
|
* powernow_k6_set_state - set the PowerNow! multiplier
|
|
* @best_i: clock_ratio[best_i] is the target multiplier
|
|
*
|
|
* Tries to change the PowerNow! multiplier
|
|
*/
|
|
static void powernow_k6_set_state(unsigned int best_i)
|
|
{
|
|
unsigned long outvalue = 0, invalue = 0;
|
|
unsigned long msrval;
|
|
struct cpufreq_freqs freqs;
|
|
|
|
if (clock_ratio[best_i].index > max_multiplier) {
|
|
printk(KERN_ERR PFX "invalid target frequency\n");
|
|
return;
|
|
}
|
|
|
|
freqs.old = busfreq * powernow_k6_get_cpu_multiplier();
|
|
freqs.new = busfreq * clock_ratio[best_i].index;
|
|
freqs.cpu = 0; /* powernow-k6.c is UP only driver */
|
|
|
|
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
|
|
|
|
/* we now need to transform best_i to the BVC format, see AMD#23446 */
|
|
|
|
outvalue = (1<<12) | (1<<10) | (1<<9) | (best_i<<5);
|
|
|
|
msrval = POWERNOW_IOPORT + 0x1;
|
|
wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */
|
|
invalue = inl(POWERNOW_IOPORT + 0x8);
|
|
invalue = invalue & 0xf;
|
|
outvalue = outvalue | invalue;
|
|
outl(outvalue , (POWERNOW_IOPORT + 0x8));
|
|
msrval = POWERNOW_IOPORT + 0x0;
|
|
wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */
|
|
|
|
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
/**
|
|
* powernow_k6_verify - verifies a new CPUfreq policy
|
|
* @policy: new policy
|
|
*
|
|
* Policy must be within lowest and highest possible CPU Frequency,
|
|
* and at least one possible state must be within min and max.
|
|
*/
|
|
static int powernow_k6_verify(struct cpufreq_policy *policy)
|
|
{
|
|
return cpufreq_frequency_table_verify(policy, &clock_ratio[0]);
|
|
}
|
|
|
|
|
|
/**
|
|
* powernow_k6_setpolicy - sets a new CPUFreq policy
|
|
* @policy: new policy
|
|
* @target_freq: the target frequency
|
|
* @relation: how that frequency relates to achieved frequency
|
|
* (CPUFREQ_RELATION_L or CPUFREQ_RELATION_H)
|
|
*
|
|
* sets a new CPUFreq policy
|
|
*/
|
|
static int powernow_k6_target(struct cpufreq_policy *policy,
|
|
unsigned int target_freq,
|
|
unsigned int relation)
|
|
{
|
|
unsigned int newstate = 0;
|
|
|
|
if (cpufreq_frequency_table_target(policy, &clock_ratio[0],
|
|
target_freq, relation, &newstate))
|
|
return -EINVAL;
|
|
|
|
powernow_k6_set_state(newstate);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int powernow_k6_cpu_init(struct cpufreq_policy *policy)
|
|
{
|
|
unsigned int i, f;
|
|
int result;
|
|
|
|
if (policy->cpu != 0)
|
|
return -ENODEV;
|
|
|
|
/* get frequencies */
|
|
max_multiplier = powernow_k6_get_cpu_multiplier();
|
|
busfreq = cpu_khz / max_multiplier;
|
|
|
|
/* table init */
|
|
for (i = 0; (clock_ratio[i].frequency != CPUFREQ_TABLE_END); i++) {
|
|
f = clock_ratio[i].index;
|
|
if (f > max_multiplier)
|
|
clock_ratio[i].frequency = CPUFREQ_ENTRY_INVALID;
|
|
else
|
|
clock_ratio[i].frequency = busfreq * f;
|
|
}
|
|
|
|
/* cpuinfo and default policy values */
|
|
policy->cpuinfo.transition_latency = 200000;
|
|
policy->cur = busfreq * max_multiplier;
|
|
|
|
result = cpufreq_frequency_table_cpuinfo(policy, clock_ratio);
|
|
if (result)
|
|
return result;
|
|
|
|
cpufreq_frequency_table_get_attr(clock_ratio, policy->cpu);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int powernow_k6_cpu_exit(struct cpufreq_policy *policy)
|
|
{
|
|
unsigned int i;
|
|
for (i = 0; i < 8; i++) {
|
|
if (i == max_multiplier)
|
|
powernow_k6_set_state(i);
|
|
}
|
|
cpufreq_frequency_table_put_attr(policy->cpu);
|
|
return 0;
|
|
}
|
|
|
|
static unsigned int powernow_k6_get(unsigned int cpu)
|
|
{
|
|
unsigned int ret;
|
|
ret = (busfreq * powernow_k6_get_cpu_multiplier());
|
|
return ret;
|
|
}
|
|
|
|
static struct freq_attr *powernow_k6_attr[] = {
|
|
&cpufreq_freq_attr_scaling_available_freqs,
|
|
NULL,
|
|
};
|
|
|
|
static struct cpufreq_driver powernow_k6_driver = {
|
|
.verify = powernow_k6_verify,
|
|
.target = powernow_k6_target,
|
|
.init = powernow_k6_cpu_init,
|
|
.exit = powernow_k6_cpu_exit,
|
|
.get = powernow_k6_get,
|
|
.name = "powernow-k6",
|
|
.owner = THIS_MODULE,
|
|
.attr = powernow_k6_attr,
|
|
};
|
|
|
|
static const struct x86_cpu_id powernow_k6_ids[] = {
|
|
{ X86_VENDOR_AMD, 5, 12 },
|
|
{ X86_VENDOR_AMD, 5, 13 },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(x86cpu, powernow_k6_ids);
|
|
|
|
/**
|
|
* powernow_k6_init - initializes the k6 PowerNow! CPUFreq driver
|
|
*
|
|
* Initializes the K6 PowerNow! support. Returns -ENODEV on unsupported
|
|
* devices, -EINVAL or -ENOMEM on problems during initiatization, and zero
|
|
* on success.
|
|
*/
|
|
static int __init powernow_k6_init(void)
|
|
{
|
|
if (!x86_match_cpu(powernow_k6_ids))
|
|
return -ENODEV;
|
|
|
|
if (!request_region(POWERNOW_IOPORT, 16, "PowerNow!")) {
|
|
printk(KERN_INFO PFX "PowerNow IOPORT region already used.\n");
|
|
return -EIO;
|
|
}
|
|
|
|
if (cpufreq_register_driver(&powernow_k6_driver)) {
|
|
release_region(POWERNOW_IOPORT, 16);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* powernow_k6_exit - unregisters AMD K6-2+/3+ PowerNow! support
|
|
*
|
|
* Unregisters AMD K6-2+ / K6-3+ PowerNow! support.
|
|
*/
|
|
static void __exit powernow_k6_exit(void)
|
|
{
|
|
cpufreq_unregister_driver(&powernow_k6_driver);
|
|
release_region(POWERNOW_IOPORT, 16);
|
|
}
|
|
|
|
|
|
MODULE_AUTHOR("Arjan van de Ven, Dave Jones <davej@redhat.com>, "
|
|
"Dominik Brodowski <linux@brodo.de>");
|
|
MODULE_DESCRIPTION("PowerNow! driver for AMD K6-2+ / K6-3+ processors.");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
module_init(powernow_k6_init);
|
|
module_exit(powernow_k6_exit);
|