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Diffstat (limited to 'arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c')
-rw-r--r--arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c266
1 files changed, 190 insertions, 76 deletions
diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c b/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
index ce54ff12c15..31c3a5baaa7 100644
--- a/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
+++ b/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
@@ -2,19 +2,15 @@
* 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>
- *
- * WARNING WARNING WARNING
- *
- * This driver manipulates the PERF_CTL MSR, which is only somewhat
- * documented. While it seems to work on my laptop, it has not been
- * tested anywhere else, and it may not work for you, do strange
- * things or simply crash.
*/
#include <linux/kernel.h>
@@ -36,7 +32,7 @@
#include <asm/cpufeature.h>
#define PFX "speedstep-centrino: "
-#define MAINTAINER "Jeremy Fitzhardinge <jeremy@goop.org>"
+#define MAINTAINER "cpufreq@lists.linux.org.uk"
#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "speedstep-centrino", msg)
@@ -351,7 +347,36 @@ static unsigned int get_cur_freq(unsigned int cpu)
#ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
-static struct acpi_processor_performance p;
+static struct acpi_processor_performance *acpi_perf_data[NR_CPUS];
+
+/*
+ * centrino_cpu_early_init_acpi - Do the preregistering with ACPI P-States
+ * library
+ *
+ * Before doing the actual init, we need to do _PSD related setup whenever
+ * supported by the BIOS. These are handled by this early_init routine.
+ */
+static int centrino_cpu_early_init_acpi(void)
+{
+ unsigned int i, j;
+ struct acpi_processor_performance *data;
+
+ for_each_cpu(i) {
+ data = kzalloc(sizeof(struct acpi_processor_performance),
+ GFP_KERNEL);
+ if (!data) {
+ for_each_cpu(j) {
+ kfree(acpi_perf_data[j]);
+ acpi_perf_data[j] = NULL;
+ }
+ return (-ENOMEM);
+ }
+ acpi_perf_data[i] = data;
+ }
+
+ acpi_processor_preregister_performance(acpi_perf_data);
+ return 0;
+}
/*
* centrino_cpu_init_acpi - register with ACPI P-States library
@@ -365,46 +390,51 @@ static int centrino_cpu_init_acpi(struct cpufreq_policy *policy)
unsigned long cur_freq;
int result = 0, i;
unsigned int cpu = policy->cpu;
+ struct acpi_processor_performance *p;
+
+ p = acpi_perf_data[cpu];
/* register with ACPI core */
- if (acpi_processor_register_performance(&p, cpu)) {
- dprintk("obtaining ACPI data failed\n");
+ if (acpi_processor_register_performance(p, cpu)) {
+ dprintk(PFX "obtaining ACPI data failed\n");
return -EIO;
}
+ policy->cpus = p->shared_cpu_map;
+ policy->shared_type = p->shared_type;
/* verify the acpi_data */
- if (p.state_count <= 1) {
+ if (p->state_count <= 1) {
dprintk("No P-States\n");
result = -ENODEV;
goto err_unreg;
}
- if ((p.control_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
- (p.status_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
+ if ((p->control_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
+ (p->status_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
dprintk("Invalid control/status registers (%x - %x)\n",
- p.control_register.space_id, p.status_register.space_id);
+ p->control_register.space_id, p->status_register.space_id);
result = -EIO;
goto err_unreg;
}
- for (i=0; i<p.state_count; i++) {
- if (p.states[i].control != p.states[i].status) {
+ for (i=0; i<p->state_count; i++) {
+ if (p->states[i].control != p->states[i].status) {
dprintk("Different control (%llu) and status values (%llu)\n",
- p.states[i].control, p.states[i].status);
+ p->states[i].control, p->states[i].status);
result = -EINVAL;
goto err_unreg;
}
- if (!p.states[i].core_frequency) {
+ if (!p->states[i].core_frequency) {
dprintk("Zero core frequency for state %u\n", i);
result = -EINVAL;
goto err_unreg;
}
- if (p.states[i].core_frequency > p.states[0].core_frequency) {
+ if (p->states[i].core_frequency > p->states[0].core_frequency) {
dprintk("P%u has larger frequency (%llu) than P0 (%llu), skipping\n", i,
- p.states[i].core_frequency, p.states[0].core_frequency);
- p.states[i].core_frequency = 0;
+ p->states[i].core_frequency, p->states[0].core_frequency);
+ p->states[i].core_frequency = 0;
continue;
}
}
@@ -416,26 +446,26 @@ static int centrino_cpu_init_acpi(struct cpufreq_policy *policy)
}
centrino_model[cpu]->model_name=NULL;
- centrino_model[cpu]->max_freq = p.states[0].core_frequency * 1000;
+ centrino_model[cpu]->max_freq = p->states[0].core_frequency * 1000;
centrino_model[cpu]->op_points = kmalloc(sizeof(struct cpufreq_frequency_table) *
- (p.state_count + 1), GFP_KERNEL);
+ (p->state_count + 1), GFP_KERNEL);
if (!centrino_model[cpu]->op_points) {
result = -ENOMEM;
goto err_kfree;
}
- for (i=0; i<p.state_count; i++) {
- centrino_model[cpu]->op_points[i].index = p.states[i].control;
- centrino_model[cpu]->op_points[i].frequency = p.states[i].core_frequency * 1000;
+ for (i=0; i<p->state_count; i++) {
+ centrino_model[cpu]->op_points[i].index = p->states[i].control;
+ centrino_model[cpu]->op_points[i].frequency = p->states[i].core_frequency * 1000;
dprintk("adding state %i with frequency %u and control value %04x\n",
i, centrino_model[cpu]->op_points[i].frequency, centrino_model[cpu]->op_points[i].index);
}
- centrino_model[cpu]->op_points[p.state_count].frequency = CPUFREQ_TABLE_END;
+ centrino_model[cpu]->op_points[p->state_count].frequency = CPUFREQ_TABLE_END;
cur_freq = get_cur_freq(cpu);
- for (i=0; i<p.state_count; i++) {
- if (!p.states[i].core_frequency) {
+ for (i=0; i<p->state_count; i++) {
+ if (!p->states[i].core_frequency) {
dprintk("skipping state %u\n", i);
centrino_model[cpu]->op_points[i].frequency = CPUFREQ_ENTRY_INVALID;
continue;
@@ -451,7 +481,7 @@ static int centrino_cpu_init_acpi(struct cpufreq_policy *policy)
}
if (cur_freq == centrino_model[cpu]->op_points[i].frequency)
- p.state = i;
+ p->state = i;
}
/* notify BIOS that we exist */
@@ -464,12 +494,13 @@ static int centrino_cpu_init_acpi(struct cpufreq_policy *policy)
err_kfree:
kfree(centrino_model[cpu]);
err_unreg:
- acpi_processor_unregister_performance(&p, cpu);
- dprintk("invalid ACPI data\n");
+ acpi_processor_unregister_performance(p, cpu);
+ dprintk(PFX "invalid ACPI data\n");
return (result);
}
#else
static inline int centrino_cpu_init_acpi(struct cpufreq_policy *policy) { return -ENODEV; }
+static inline int centrino_cpu_early_init_acpi(void) { return 0; }
#endif
static int centrino_cpu_init(struct cpufreq_policy *policy)
@@ -555,10 +586,15 @@ static int centrino_cpu_exit(struct cpufreq_policy *policy)
#ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
if (!centrino_model[cpu]->model_name) {
- dprintk("unregistering and freeing ACPI data\n");
- acpi_processor_unregister_performance(&p, cpu);
- kfree(centrino_model[cpu]->op_points);
- kfree(centrino_model[cpu]);
+ static struct acpi_processor_performance *p;
+
+ if (acpi_perf_data[cpu]) {
+ p = acpi_perf_data[cpu];
+ dprintk("unregistering and freeing ACPI data\n");
+ acpi_processor_unregister_performance(p, cpu);
+ kfree(centrino_model[cpu]->op_points);
+ kfree(centrino_model[cpu]);
+ }
}
#endif
@@ -592,63 +628,128 @@ static int centrino_target (struct cpufreq_policy *policy,
unsigned int relation)
{
unsigned int newstate = 0;
- unsigned int msr, oldmsr, h, cpu = policy->cpu;
+ unsigned int msr, oldmsr = 0, h = 0, cpu = policy->cpu;
struct cpufreq_freqs freqs;
+ cpumask_t online_policy_cpus;
cpumask_t saved_mask;
- int retval;
+ cpumask_t set_mask;
+ cpumask_t covered_cpus;
+ int retval = 0;
+ unsigned int j, k, first_cpu, tmp;
- if (centrino_model[cpu] == NULL)
+ if (unlikely(centrino_model[cpu] == NULL))
return -ENODEV;
- /*
- * Support for SMP systems.
- * Make sure we are running on the CPU that wants to change frequency
- */
- saved_mask = current->cpus_allowed;
- set_cpus_allowed(current, policy->cpus);
- if (!cpu_isset(smp_processor_id(), policy->cpus)) {
- dprintk("couldn't limit to CPUs in this domain\n");
- return(-EAGAIN);
+ if (unlikely(cpufreq_frequency_table_target(policy,
+ centrino_model[cpu]->op_points,
+ target_freq,
+ relation,
+ &newstate))) {
+ return -EINVAL;
}
- if (cpufreq_frequency_table_target(policy, centrino_model[cpu]->op_points, target_freq,
- relation, &newstate)) {
- retval = -EINVAL;
- goto migrate_end;
- }
+#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
- msr = centrino_model[cpu]->op_points[newstate].index;
- rdmsr(MSR_IA32_PERF_CTL, oldmsr, h);
+ 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);
+ 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;
+ }
+ break;
+ }
- if (msr == (oldmsr & 0xffff)) {
- retval = 0;
- dprintk("no change needed - msr was and needs to be %x\n", oldmsr);
- goto migrate_end;
- }
+ 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;
+ }
- freqs.cpu = cpu;
- freqs.old = extract_clock(oldmsr, cpu, 0);
- freqs.new = extract_clock(msr, cpu, 0);
+ wrmsr(MSR_IA32_PERF_CTL, oldmsr, h);
+ if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
+ break;
- dprintk("target=%dkHz old=%d new=%d msr=%04x\n",
- target_freq, freqs.old, freqs.new, msr);
+ cpu_set(j, covered_cpus);
+ }
- cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+ for_each_cpu_mask(k, online_policy_cpus) {
+ freqs.cpu = k;
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+ }
- /* all but 16 LSB are "reserved", so treat them with
- care */
- oldmsr &= ~0xffff;
- msr &= 0xffff;
- oldmsr |= msr;
+ 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..
+ */
- wrmsr(MSR_IA32_PERF_CTL, oldmsr, h);
+ 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);
+ }
+ }
- cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+ 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);
+ }
+ }
- retval = 0;
migrate_end:
set_cpus_allowed(current, saved_mask);
- return (retval);
+ return 0;
}
static struct freq_attr* centrino_attr[] = {
@@ -690,12 +791,25 @@ static int __init centrino_init(void)
if (!cpu_has(cpu, X86_FEATURE_EST))
return -ENODEV;
+ centrino_cpu_early_init_acpi();
+
return cpufreq_register_driver(&centrino_driver);
}
static void __exit centrino_exit(void)
{
+#ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
+ unsigned int j;
+#endif
+
cpufreq_unregister_driver(&centrino_driver);
+
+#ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
+ for_each_cpu(j) {
+ kfree(acpi_perf_data[j]);
+ acpi_perf_data[j] = NULL;
+ }
+#endif
}
MODULE_AUTHOR ("Jeremy Fitzhardinge <jeremy@goop.org>");