+++ /dev/null
-/*
- * cpufreq driver for Enhanced SpeedStep, as found in Intel's Pentium
- * M (part of the Centrino chipset).
- *
- * Since the original Pentium M, most new Intel CPUs support Enhanced
- * SpeedStep.
- *
- * Despite the "SpeedStep" in the name, this is almost entirely unlike
- * traditional SpeedStep.
- *
- * Modelled on speedstep.c
- *
- * Copyright (C) 2003 Jeremy Fitzhardinge <jeremy@goop.org>
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/cpufreq.h>
-#include <linux/sched.h> /* current */
-#include <linux/delay.h>
-#include <linux/compiler.h>
-
-#include <asm/msr.h>
-#include <asm/processor.h>
-#include <asm/cpufeature.h>
-
-#define PFX "speedstep-centrino: "
-#define MAINTAINER "cpufreq@lists.linux.org.uk"
-
-#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "speedstep-centrino", msg)
-
-#define INTEL_MSR_RANGE (0xffff)
-
-struct cpu_id
-{
- __u8 x86; /* CPU family */
- __u8 x86_model; /* model */
- __u8 x86_mask; /* stepping */
-};
-
-enum {
- CPU_BANIAS,
- CPU_DOTHAN_A1,
- CPU_DOTHAN_A2,
- CPU_DOTHAN_B0,
- CPU_MP4HT_D0,
- CPU_MP4HT_E0,
-};
-
-static const struct cpu_id cpu_ids[] = {
- [CPU_BANIAS] = { 6, 9, 5 },
- [CPU_DOTHAN_A1] = { 6, 13, 1 },
- [CPU_DOTHAN_A2] = { 6, 13, 2 },
- [CPU_DOTHAN_B0] = { 6, 13, 6 },
- [CPU_MP4HT_D0] = {15, 3, 4 },
- [CPU_MP4HT_E0] = {15, 4, 1 },
-};
-#define N_IDS ARRAY_SIZE(cpu_ids)
-
-struct cpu_model
-{
- const struct cpu_id *cpu_id;
- const char *model_name;
- unsigned max_freq; /* max clock in kHz */
-
- struct cpufreq_frequency_table *op_points; /* clock/voltage pairs */
-};
-static int centrino_verify_cpu_id(const struct cpuinfo_x86 *c, const struct cpu_id *x);
-
-/* Operating points for current CPU */
-static struct cpu_model *centrino_model[NR_CPUS];
-static const struct cpu_id *centrino_cpu[NR_CPUS];
-
-static struct cpufreq_driver centrino_driver;
-
-#ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE
-
-/* Computes the correct form for IA32_PERF_CTL MSR for a particular
- frequency/voltage operating point; frequency in MHz, volts in mV.
- This is stored as "index" in the structure. */
-#define OP(mhz, mv) \
- { \
- .frequency = (mhz) * 1000, \
- .index = (((mhz)/100) << 8) | ((mv - 700) / 16) \
- }
-
-/*
- * These voltage tables were derived from the Intel Pentium M
- * datasheet, document 25261202.pdf, Table 5. I have verified they
- * are consistent with my IBM ThinkPad X31, which has a 1.3GHz Pentium
- * M.
- */
-
-/* Ultra Low Voltage Intel Pentium M processor 900MHz (Banias) */
-static struct cpufreq_frequency_table banias_900[] =
-{
- OP(600, 844),
- OP(800, 988),
- OP(900, 1004),
- { .frequency = CPUFREQ_TABLE_END }
-};
-
-/* Ultra Low Voltage Intel Pentium M processor 1000MHz (Banias) */
-static struct cpufreq_frequency_table banias_1000[] =
-{
- OP(600, 844),
- OP(800, 972),
- OP(900, 988),
- OP(1000, 1004),
- { .frequency = CPUFREQ_TABLE_END }
-};
-
-/* Low Voltage Intel Pentium M processor 1.10GHz (Banias) */
-static struct cpufreq_frequency_table banias_1100[] =
-{
- OP( 600, 956),
- OP( 800, 1020),
- OP( 900, 1100),
- OP(1000, 1164),
- OP(1100, 1180),
- { .frequency = CPUFREQ_TABLE_END }
-};
-
-
-/* Low Voltage Intel Pentium M processor 1.20GHz (Banias) */
-static struct cpufreq_frequency_table banias_1200[] =
-{
- OP( 600, 956),
- OP( 800, 1004),
- OP( 900, 1020),
- OP(1000, 1100),
- OP(1100, 1164),
- OP(1200, 1180),
- { .frequency = CPUFREQ_TABLE_END }
-};
-
-/* Intel Pentium M processor 1.30GHz (Banias) */
-static struct cpufreq_frequency_table banias_1300[] =
-{
- OP( 600, 956),
- OP( 800, 1260),
- OP(1000, 1292),
- OP(1200, 1356),
- OP(1300, 1388),
- { .frequency = CPUFREQ_TABLE_END }
-};
-
-/* Intel Pentium M processor 1.40GHz (Banias) */
-static struct cpufreq_frequency_table banias_1400[] =
-{
- OP( 600, 956),
- OP( 800, 1180),
- OP(1000, 1308),
- OP(1200, 1436),
- OP(1400, 1484),
- { .frequency = CPUFREQ_TABLE_END }
-};
-
-/* Intel Pentium M processor 1.50GHz (Banias) */
-static struct cpufreq_frequency_table banias_1500[] =
-{
- OP( 600, 956),
- OP( 800, 1116),
- OP(1000, 1228),
- OP(1200, 1356),
- OP(1400, 1452),
- OP(1500, 1484),
- { .frequency = CPUFREQ_TABLE_END }
-};
-
-/* Intel Pentium M processor 1.60GHz (Banias) */
-static struct cpufreq_frequency_table banias_1600[] =
-{
- OP( 600, 956),
- OP( 800, 1036),
- OP(1000, 1164),
- OP(1200, 1276),
- OP(1400, 1420),
- OP(1600, 1484),
- { .frequency = CPUFREQ_TABLE_END }
-};
-
-/* Intel Pentium M processor 1.70GHz (Banias) */
-static struct cpufreq_frequency_table banias_1700[] =
-{
- OP( 600, 956),
- OP( 800, 1004),
- OP(1000, 1116),
- OP(1200, 1228),
- OP(1400, 1308),
- OP(1700, 1484),
- { .frequency = CPUFREQ_TABLE_END }
-};
-#undef OP
-
-#define _BANIAS(cpuid, max, name) \
-{ .cpu_id = cpuid, \
- .model_name = "Intel(R) Pentium(R) M processor " name "MHz", \
- .max_freq = (max)*1000, \
- .op_points = banias_##max, \
-}
-#define BANIAS(max) _BANIAS(&cpu_ids[CPU_BANIAS], max, #max)
-
-/* CPU models, their operating frequency range, and freq/voltage
- operating points */
-static struct cpu_model models[] =
-{
- _BANIAS(&cpu_ids[CPU_BANIAS], 900, " 900"),
- BANIAS(1000),
- BANIAS(1100),
- BANIAS(1200),
- BANIAS(1300),
- BANIAS(1400),
- BANIAS(1500),
- BANIAS(1600),
- BANIAS(1700),
-
- /* NULL model_name is a wildcard */
- { &cpu_ids[CPU_DOTHAN_A1], NULL, 0, NULL },
- { &cpu_ids[CPU_DOTHAN_A2], NULL, 0, NULL },
- { &cpu_ids[CPU_DOTHAN_B0], NULL, 0, NULL },
- { &cpu_ids[CPU_MP4HT_D0], NULL, 0, NULL },
- { &cpu_ids[CPU_MP4HT_E0], NULL, 0, NULL },
-
- { NULL, }
-};
-#undef _BANIAS
-#undef BANIAS
-
-static int centrino_cpu_init_table(struct cpufreq_policy *policy)
-{
- struct cpuinfo_x86 *cpu = &cpu_data[policy->cpu];
- struct cpu_model *model;
-
- for(model = models; model->cpu_id != NULL; model++)
- if (centrino_verify_cpu_id(cpu, model->cpu_id) &&
- (model->model_name == NULL ||
- strcmp(cpu->x86_model_id, model->model_name) == 0))
- break;
-
- if (model->cpu_id == NULL) {
- /* No match at all */
- dprintk("no support for CPU model \"%s\": "
- "send /proc/cpuinfo to " MAINTAINER "\n",
- cpu->x86_model_id);
- return -ENOENT;
- }
-
- if (model->op_points == NULL) {
- /* Matched a non-match */
- dprintk("no table support for CPU model \"%s\"\n",
- cpu->x86_model_id);
- dprintk("try using the acpi-cpufreq driver\n");
- return -ENOENT;
- }
-
- centrino_model[policy->cpu] = model;
-
- dprintk("found \"%s\": max frequency: %dkHz\n",
- model->model_name, model->max_freq);
-
- return 0;
-}
-
-#else
-static inline int centrino_cpu_init_table(struct cpufreq_policy *policy) { return -ENODEV; }
-#endif /* CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE */
-
-static int centrino_verify_cpu_id(const struct cpuinfo_x86 *c, const struct cpu_id *x)
-{
- if ((c->x86 == x->x86) &&
- (c->x86_model == x->x86_model) &&
- (c->x86_mask == x->x86_mask))
- return 1;
- return 0;
-}
-
-/* To be called only after centrino_model is initialized */
-static unsigned extract_clock(unsigned msr, unsigned int cpu, int failsafe)
-{
- int i;
-
- /*
- * Extract clock in kHz from PERF_CTL value
- * for centrino, as some DSDTs are buggy.
- * Ideally, this can be done using the acpi_data structure.
- */
- if ((centrino_cpu[cpu] == &cpu_ids[CPU_BANIAS]) ||
- (centrino_cpu[cpu] == &cpu_ids[CPU_DOTHAN_A1]) ||
- (centrino_cpu[cpu] == &cpu_ids[CPU_DOTHAN_B0])) {
- msr = (msr >> 8) & 0xff;
- return msr * 100000;
- }
-
- if ((!centrino_model[cpu]) || (!centrino_model[cpu]->op_points))
- return 0;
-
- msr &= 0xffff;
- for (i=0;centrino_model[cpu]->op_points[i].frequency != CPUFREQ_TABLE_END; i++) {
- if (msr == centrino_model[cpu]->op_points[i].index)
- return centrino_model[cpu]->op_points[i].frequency;
- }
- if (failsafe)
- return centrino_model[cpu]->op_points[i-1].frequency;
- else
- return 0;
-}
-
-/* Return the current CPU frequency in kHz */
-static unsigned int get_cur_freq(unsigned int cpu)
-{
- unsigned l, h;
- unsigned clock_freq;
- cpumask_t saved_mask;
-
- saved_mask = current->cpus_allowed;
- set_cpus_allowed(current, cpumask_of_cpu(cpu));
- if (smp_processor_id() != cpu)
- return 0;
-
- rdmsr(MSR_IA32_PERF_STATUS, l, h);
- clock_freq = extract_clock(l, cpu, 0);
-
- if (unlikely(clock_freq == 0)) {
- /*
- * On some CPUs, we can see transient MSR values (which are
- * not present in _PSS), while CPU is doing some automatic
- * P-state transition (like TM2). Get the last freq set
- * in PERF_CTL.
- */
- rdmsr(MSR_IA32_PERF_CTL, l, h);
- clock_freq = extract_clock(l, cpu, 1);
- }
-
- set_cpus_allowed(current, saved_mask);
- return clock_freq;
-}
-
-
-static int centrino_cpu_init(struct cpufreq_policy *policy)
-{
- struct cpuinfo_x86 *cpu = &cpu_data[policy->cpu];
- unsigned freq;
- unsigned l, h;
- int ret;
- int i;
-
- /* Only Intel makes Enhanced Speedstep-capable CPUs */
- if (cpu->x86_vendor != X86_VENDOR_INTEL || !cpu_has(cpu, X86_FEATURE_EST))
- return -ENODEV;
-
- if (cpu_has(cpu, X86_FEATURE_CONSTANT_TSC))
- centrino_driver.flags |= CPUFREQ_CONST_LOOPS;
-
- if (policy->cpu != 0)
- return -ENODEV;
-
- for (i = 0; i < N_IDS; i++)
- if (centrino_verify_cpu_id(cpu, &cpu_ids[i]))
- break;
-
- if (i != N_IDS)
- centrino_cpu[policy->cpu] = &cpu_ids[i];
-
- if (!centrino_cpu[policy->cpu]) {
- dprintk("found unsupported CPU with "
- "Enhanced SpeedStep: send /proc/cpuinfo to "
- MAINTAINER "\n");
- return -ENODEV;
- }
-
- if (centrino_cpu_init_table(policy)) {
- return -ENODEV;
- }
-
- /* Check to see if Enhanced SpeedStep is enabled, and try to
- enable it if not. */
- rdmsr(MSR_IA32_MISC_ENABLE, l, h);
-
- if (!(l & (1<<16))) {
- l |= (1<<16);
- dprintk("trying to enable Enhanced SpeedStep (%x)\n", l);
- wrmsr(MSR_IA32_MISC_ENABLE, l, h);
-
- /* check to see if it stuck */
- rdmsr(MSR_IA32_MISC_ENABLE, l, h);
- if (!(l & (1<<16))) {
- printk(KERN_INFO PFX "couldn't enable Enhanced SpeedStep\n");
- return -ENODEV;
- }
- }
-
- freq = get_cur_freq(policy->cpu);
-
- policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
- policy->cpuinfo.transition_latency = 10000; /* 10uS transition latency */
- policy->cur = freq;
-
- dprintk("centrino_cpu_init: cur=%dkHz\n", policy->cur);
-
- ret = cpufreq_frequency_table_cpuinfo(policy, centrino_model[policy->cpu]->op_points);
- if (ret)
- return (ret);
-
- cpufreq_frequency_table_get_attr(centrino_model[policy->cpu]->op_points, policy->cpu);
-
- return 0;
-}
-
-static int centrino_cpu_exit(struct cpufreq_policy *policy)
-{
- unsigned int cpu = policy->cpu;
-
- if (!centrino_model[cpu])
- return -ENODEV;
-
- cpufreq_frequency_table_put_attr(cpu);
-
- centrino_model[cpu] = NULL;
-
- return 0;
-}
-
-/**
- * centrino_verify - verifies a new CPUFreq policy
- * @policy: new policy
- *
- * Limit must be within this model's frequency range at least one
- * border included.
- */
-static int centrino_verify (struct cpufreq_policy *policy)
-{
- return cpufreq_frequency_table_verify(policy, centrino_model[policy->cpu]->op_points);
-}
-
-/**
- * centrino_setpolicy - set 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 centrino_target (struct cpufreq_policy *policy,
- unsigned int target_freq,
- unsigned int relation)
-{
- unsigned int newstate = 0;
- unsigned int msr, oldmsr = 0, h = 0, cpu = policy->cpu;
- struct cpufreq_freqs freqs;
- cpumask_t online_policy_cpus;
- cpumask_t saved_mask;
- cpumask_t set_mask;
- cpumask_t covered_cpus;
- int retval = 0;
- unsigned int j, k, first_cpu, tmp;
-
- if (unlikely(centrino_model[cpu] == NULL))
- return -ENODEV;
-
- if (unlikely(cpufreq_frequency_table_target(policy,
- centrino_model[cpu]->op_points,
- target_freq,
- relation,
- &newstate))) {
- return -EINVAL;
- }
-
-#ifdef CONFIG_HOTPLUG_CPU
- /* cpufreq holds the hotplug lock, so we are safe from here on */
- cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
-#else
- online_policy_cpus = policy->cpus;
-#endif
-
- saved_mask = current->cpus_allowed;
- first_cpu = 1;
- cpus_clear(covered_cpus);
- for_each_cpu_mask(j, online_policy_cpus) {
- /*
- * Support for SMP systems.
- * Make sure we are running on CPU that wants to change freq
- */
- cpus_clear(set_mask);
- if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
- cpus_or(set_mask, set_mask, online_policy_cpus);
- else
- cpu_set(j, set_mask);
-
- set_cpus_allowed(current, set_mask);
- preempt_disable();
- if (unlikely(!cpu_isset(smp_processor_id(), set_mask))) {
- dprintk("couldn't limit to CPUs in this domain\n");
- retval = -EAGAIN;
- if (first_cpu) {
- /* We haven't started the transition yet. */
- goto migrate_end;
- }
- preempt_enable();
- break;
- }
-
- msr = centrino_model[cpu]->op_points[newstate].index;
-
- if (first_cpu) {
- rdmsr(MSR_IA32_PERF_CTL, oldmsr, h);
- if (msr == (oldmsr & 0xffff)) {
- dprintk("no change needed - msr was and needs "
- "to be %x\n", oldmsr);
- retval = 0;
- goto migrate_end;
- }
-
- freqs.old = extract_clock(oldmsr, cpu, 0);
- freqs.new = extract_clock(msr, cpu, 0);
-
- dprintk("target=%dkHz old=%d new=%d msr=%04x\n",
- target_freq, freqs.old, freqs.new, msr);
-
- for_each_cpu_mask(k, online_policy_cpus) {
- freqs.cpu = k;
- cpufreq_notify_transition(&freqs,
- CPUFREQ_PRECHANGE);
- }
-
- first_cpu = 0;
- /* all but 16 LSB are reserved, treat them with care */
- oldmsr &= ~0xffff;
- msr &= 0xffff;
- oldmsr |= msr;
- }
-
- wrmsr(MSR_IA32_PERF_CTL, oldmsr, h);
- if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
- preempt_enable();
- break;
- }
-
- cpu_set(j, covered_cpus);
- preempt_enable();
- }
-
- for_each_cpu_mask(k, online_policy_cpus) {
- freqs.cpu = k;
- cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
- }
-
- if (unlikely(retval)) {
- /*
- * We have failed halfway through the frequency change.
- * We have sent callbacks to policy->cpus and
- * MSRs have already been written on coverd_cpus.
- * Best effort undo..
- */
-
- if (!cpus_empty(covered_cpus)) {
- for_each_cpu_mask(j, covered_cpus) {
- set_cpus_allowed(current, cpumask_of_cpu(j));
- wrmsr(MSR_IA32_PERF_CTL, oldmsr, h);
- }
- }
-
- tmp = freqs.new;
- freqs.new = freqs.old;
- freqs.old = tmp;
- for_each_cpu_mask(j, online_policy_cpus) {
- freqs.cpu = j;
- cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
- cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
- }
- }
- set_cpus_allowed(current, saved_mask);
- return 0;
-
-migrate_end:
- preempt_enable();
- set_cpus_allowed(current, saved_mask);
- return 0;
-}
-
-static struct freq_attr* centrino_attr[] = {
- &cpufreq_freq_attr_scaling_available_freqs,
- NULL,
-};
-
-static struct cpufreq_driver centrino_driver = {
- .name = "centrino", /* should be speedstep-centrino,
- but there's a 16 char limit */
- .init = centrino_cpu_init,
- .exit = centrino_cpu_exit,
- .verify = centrino_verify,
- .target = centrino_target,
- .get = get_cur_freq,
- .attr = centrino_attr,
- .owner = THIS_MODULE,
-};
-
-
-/**
- * centrino_init - initializes the Enhanced SpeedStep CPUFreq driver
- *
- * Initializes the Enhanced SpeedStep support. Returns -ENODEV on
- * unsupported devices, -ENOENT if there's no voltage table for this
- * particular CPU model, -EINVAL on problems during initiatization,
- * and zero on success.
- *
- * This is quite picky. Not only does the CPU have to advertise the
- * "est" flag in the cpuid capability flags, we look for a specific
- * CPU model and stepping, and we need to have the exact model name in
- * our voltage tables. That is, be paranoid about not releasing
- * someone's valuable magic smoke.
- */
-static int __init centrino_init(void)
-{
- struct cpuinfo_x86 *cpu = cpu_data;
-
- if (!cpu_has(cpu, X86_FEATURE_EST))
- return -ENODEV;
-
- return cpufreq_register_driver(¢rino_driver);
-}
-
-static void __exit centrino_exit(void)
-{
- cpufreq_unregister_driver(¢rino_driver);
-}
-
-MODULE_AUTHOR ("Jeremy Fitzhardinge <jeremy@goop.org>");
-MODULE_DESCRIPTION ("Enhanced SpeedStep driver for Intel Pentium M processors.");
-MODULE_LICENSE ("GPL");
-
-late_initcall(centrino_init);
-module_exit(centrino_exit);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff