+++ /dev/null
-/*
- * Intel SpeedStep SMI driver.
- *
- * (C) 2003 Hiroshi Miura <miura@da-cha.org>
- *
- * Licensed under the terms of the GNU GPL License version 2.
- *
- */
-
-
-/*********************************************************************
- * SPEEDSTEP - DEFINITIONS *
- *********************************************************************/
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/init.h>
-#include <linux/cpufreq.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
-#include <asm/ist.h>
-#include <asm/io.h>
-
-#include "speedstep-lib.h"
-
-/* speedstep system management interface port/command.
- *
- * These parameters are got from IST-SMI BIOS call.
- * If user gives it, these are used.
- *
- */
-static int smi_port = 0;
-static int smi_cmd = 0;
-static unsigned int smi_sig = 0;
-
-/* info about the processor */
-static unsigned int speedstep_processor = 0;
-
-/*
- * There are only two frequency states for each processor. Values
- * are in kHz for the time being.
- */
-static struct cpufreq_frequency_table speedstep_freqs[] = {
- {SPEEDSTEP_HIGH, 0},
- {SPEEDSTEP_LOW, 0},
- {0, CPUFREQ_TABLE_END},
-};
-
-#define GET_SPEEDSTEP_OWNER 0
-#define GET_SPEEDSTEP_STATE 1
-#define SET_SPEEDSTEP_STATE 2
-#define GET_SPEEDSTEP_FREQS 4
-
-/* how often shall the SMI call be tried if it failed, e.g. because
- * of DMA activity going on? */
-#define SMI_TRIES 5
-
-#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "speedstep-smi", msg)
-
-/**
- * speedstep_smi_ownership
- */
-static int speedstep_smi_ownership (void)
-{
- u32 command, result, magic;
- u32 function = GET_SPEEDSTEP_OWNER;
- unsigned char magic_data[] = "Copyright (c) 1999 Intel Corporation";
-
- command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
- magic = virt_to_phys(magic_data);
-
- dprintk("trying to obtain ownership with command %x at port %x\n", command, smi_port);
-
- __asm__ __volatile__(
- "out %%al, (%%dx)\n"
- : "=D" (result)
- : "a" (command), "b" (function), "c" (0), "d" (smi_port),
- "D" (0), "S" (magic)
- : "memory"
- );
-
- dprintk("result is %x\n", result);
-
- return result;
-}
-
-/**
- * speedstep_smi_get_freqs - get SpeedStep preferred & current freq.
- * @low: the low frequency value is placed here
- * @high: the high frequency value is placed here
- *
- * Only available on later SpeedStep-enabled systems, returns false results or
- * even hangs [cf. bugme.osdl.org # 1422] on earlier systems. Empirical testing
- * shows that the latter occurs if !(ist_info.event & 0xFFFF).
- */
-static int speedstep_smi_get_freqs (unsigned int *low, unsigned int *high)
-{
- u32 command, result = 0, edi, high_mhz, low_mhz;
- u32 state=0;
- u32 function = GET_SPEEDSTEP_FREQS;
-
- if (!(ist_info.event & 0xFFFF)) {
- dprintk("bug #1422 -- can't read freqs from BIOS\n");
- return -ENODEV;
- }
-
- command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
-
- dprintk("trying to determine frequencies with command %x at port %x\n", command, smi_port);
-
- __asm__ __volatile__("movl $0, %%edi\n"
- "out %%al, (%%dx)\n"
- : "=a" (result), "=b" (high_mhz), "=c" (low_mhz), "=d" (state), "=D" (edi)
- : "a" (command), "b" (function), "c" (state), "d" (smi_port), "S" (0)
- );
-
- dprintk("result %x, low_freq %u, high_freq %u\n", result, low_mhz, high_mhz);
-
- /* abort if results are obviously incorrect... */
- if ((high_mhz + low_mhz) < 600)
- return -EINVAL;
-
- *high = high_mhz * 1000;
- *low = low_mhz * 1000;
-
- return result;
-}
-
-/**
- * speedstep_get_state - set the SpeedStep state
- * @state: processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH)
- *
- */
-static int speedstep_get_state (void)
-{
- u32 function=GET_SPEEDSTEP_STATE;
- u32 result, state, edi, command;
-
- command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
-
- dprintk("trying to determine current setting with command %x at port %x\n", command, smi_port);
-
- __asm__ __volatile__("movl $0, %%edi\n"
- "out %%al, (%%dx)\n"
- : "=a" (result), "=b" (state), "=D" (edi)
- : "a" (command), "b" (function), "c" (0), "d" (smi_port), "S" (0)
- );
-
- dprintk("state is %x, result is %x\n", state, result);
-
- return (state & 1);
-}
-
-
-/**
- * speedstep_set_state - set the SpeedStep state
- * @state: new processor frequency state (SPEEDSTEP_LOW or SPEEDSTEP_HIGH)
- *
- */
-static void speedstep_set_state (unsigned int state)
-{
- unsigned int result = 0, command, new_state;
- unsigned long flags;
- unsigned int function=SET_SPEEDSTEP_STATE;
- unsigned int retry = 0;
-
- if (state > 0x1)
- return;
-
- /* Disable IRQs */
- local_irq_save(flags);
-
- command = (smi_sig & 0xffffff00) | (smi_cmd & 0xff);
-
- dprintk("trying to set frequency to state %u with command %x at port %x\n", state, command, smi_port);
-
- do {
- if (retry) {
- dprintk("retry %u, previous result %u, waiting...\n", retry, result);
- mdelay(retry * 50);
- }
- retry++;
- __asm__ __volatile__(
- "movl $0, %%edi\n"
- "out %%al, (%%dx)\n"
- : "=b" (new_state), "=D" (result)
- : "a" (command), "b" (function), "c" (state), "d" (smi_port), "S" (0)
- );
- } while ((new_state != state) && (retry <= SMI_TRIES));
-
- /* enable IRQs */
- local_irq_restore(flags);
-
- if (new_state == state) {
- dprintk("change to %u MHz succeeded after %u tries with result %u\n", (speedstep_freqs[new_state].frequency / 1000), retry, result);
- } else {
- printk(KERN_ERR "cpufreq: change failed with new_state %u and result %u\n", new_state, result);
- }
-
- return;
-}
-
-
-/**
- * speedstep_target - set a new CPUFreq policy
- * @policy: new policy
- * @target_freq: new freq
- * @relation:
- *
- * Sets a new CPUFreq policy/freq.
- */
-static int speedstep_target (struct cpufreq_policy *policy,
- unsigned int target_freq, unsigned int relation)
-{
- unsigned int newstate = 0;
- struct cpufreq_freqs freqs;
-
- if (cpufreq_frequency_table_target(policy, &speedstep_freqs[0], target_freq, relation, &newstate))
- return -EINVAL;
-
- freqs.old = speedstep_freqs[speedstep_get_state()].frequency;
- freqs.new = speedstep_freqs[newstate].frequency;
- freqs.cpu = 0; /* speedstep.c is UP only driver */
-
- if (freqs.old == freqs.new)
- return 0;
-
- cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
- speedstep_set_state(newstate);
- cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
-
- return 0;
-}
-
-
-/**
- * speedstep_verify - verifies a new CPUFreq policy
- * @policy: new policy
- *
- * Limit must be within speedstep_low_freq and speedstep_high_freq, with
- * at least one border included.
- */
-static int speedstep_verify (struct cpufreq_policy *policy)
-{
- return cpufreq_frequency_table_verify(policy, &speedstep_freqs[0]);
-}
-
-
-static int speedstep_cpu_init(struct cpufreq_policy *policy)
-{
- int result;
- unsigned int speed,state;
-
- /* capability check */
- if (policy->cpu != 0)
- return -ENODEV;
-
- result = speedstep_smi_ownership();
- if (result) {
- dprintk("fails in aquiring ownership of a SMI interface.\n");
- return -EINVAL;
- }
-
- /* detect low and high frequency */
- result = speedstep_smi_get_freqs(&speedstep_freqs[SPEEDSTEP_LOW].frequency,
- &speedstep_freqs[SPEEDSTEP_HIGH].frequency);
- if (result) {
- /* fall back to speedstep_lib.c dection mechanism: try both states out */
- dprintk("could not detect low and high frequencies by SMI call.\n");
- result = speedstep_get_freqs(speedstep_processor,
- &speedstep_freqs[SPEEDSTEP_LOW].frequency,
- &speedstep_freqs[SPEEDSTEP_HIGH].frequency,
- NULL,
- &speedstep_set_state);
-
- if (result) {
- dprintk("could not detect two different speeds -- aborting.\n");
- return result;
- } else
- dprintk("workaround worked.\n");
- }
-
- /* get current speed setting */
- state = speedstep_get_state();
- speed = speedstep_freqs[state].frequency;
-
- dprintk("currently at %s speed setting - %i MHz\n",
- (speed == speedstep_freqs[SPEEDSTEP_LOW].frequency) ? "low" : "high",
- (speed / 1000));
-
- /* cpuinfo and default policy values */
- policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
- policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
- policy->cur = speed;
-
- result = cpufreq_frequency_table_cpuinfo(policy, speedstep_freqs);
- if (result)
- return (result);
-
- cpufreq_frequency_table_get_attr(speedstep_freqs, policy->cpu);
-
- return 0;
-}
-
-static int speedstep_cpu_exit(struct cpufreq_policy *policy)
-{
- cpufreq_frequency_table_put_attr(policy->cpu);
- return 0;
-}
-
-static unsigned int speedstep_get(unsigned int cpu)
-{
- if (cpu)
- return -ENODEV;
- return speedstep_get_processor_frequency(speedstep_processor);
-}
-
-
-static int speedstep_resume(struct cpufreq_policy *policy)
-{
- int result = speedstep_smi_ownership();
-
- if (result)
- dprintk("fails in re-aquiring ownership of a SMI interface.\n");
-
- return result;
-}
-
-static struct freq_attr* speedstep_attr[] = {
- &cpufreq_freq_attr_scaling_available_freqs,
- NULL,
-};
-
-static struct cpufreq_driver speedstep_driver = {
- .name = "speedstep-smi",
- .verify = speedstep_verify,
- .target = speedstep_target,
- .init = speedstep_cpu_init,
- .exit = speedstep_cpu_exit,
- .get = speedstep_get,
- .resume = speedstep_resume,
- .owner = THIS_MODULE,
- .attr = speedstep_attr,
-};
-
-/**
- * speedstep_init - initializes the SpeedStep CPUFreq driver
- *
- * Initializes the SpeedStep support. Returns -ENODEV on unsupported
- * BIOS, -EINVAL on problems during initiatization, and zero on
- * success.
- */
-static int __init speedstep_init(void)
-{
- speedstep_processor = speedstep_detect_processor();
-
- switch (speedstep_processor) {
- case SPEEDSTEP_PROCESSOR_PIII_T:
- case SPEEDSTEP_PROCESSOR_PIII_C:
- case SPEEDSTEP_PROCESSOR_PIII_C_EARLY:
- break;
- default:
- speedstep_processor = 0;
- }
-
- if (!speedstep_processor) {
- dprintk ("No supported Intel CPU detected.\n");
- return -ENODEV;
- }
-
- dprintk("signature:0x%.8lx, command:0x%.8lx, event:0x%.8lx, perf_level:0x%.8lx.\n",
- ist_info.signature, ist_info.command, ist_info.event, ist_info.perf_level);
-
- /* Error if no IST-SMI BIOS or no PARM
- sig= 'ISGE' aka 'Intel Speedstep Gate E' */
- if ((ist_info.signature != 0x47534943) && (
- (smi_port == 0) || (smi_cmd == 0)))
- return -ENODEV;
-
- if (smi_sig == 1)
- smi_sig = 0x47534943;
- else
- smi_sig = ist_info.signature;
-
- /* setup smi_port from MODLULE_PARM or BIOS */
- if ((smi_port > 0xff) || (smi_port < 0))
- return -EINVAL;
- else if (smi_port == 0)
- smi_port = ist_info.command & 0xff;
-
- if ((smi_cmd > 0xff) || (smi_cmd < 0))
- return -EINVAL;
- else if (smi_cmd == 0)
- smi_cmd = (ist_info.command >> 16) & 0xff;
-
- return cpufreq_register_driver(&speedstep_driver);
-}
-
-
-/**
- * speedstep_exit - unregisters SpeedStep support
- *
- * Unregisters SpeedStep support.
- */
-static void __exit speedstep_exit(void)
-{
- cpufreq_unregister_driver(&speedstep_driver);
-}
-
-module_param(smi_port, int, 0444);
-module_param(smi_cmd, int, 0444);
-module_param(smi_sig, uint, 0444);
-
-MODULE_PARM_DESC(smi_port, "Override the BIOS-given IST port with this value -- Intel's default setting is 0xb2");
-MODULE_PARM_DESC(smi_cmd, "Override the BIOS-given IST command with this value -- Intel's default setting is 0x82");
-MODULE_PARM_DESC(smi_sig, "Set to 1 to fake the IST signature when using the SMI interface.");
-
-MODULE_AUTHOR ("Hiroshi Miura");
-MODULE_DESCRIPTION ("Speedstep driver for IST applet SMI interface.");
-MODULE_LICENSE ("GPL");
-
-module_init(speedstep_init);
-module_exit(speedstep_exit);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff