P-state software coordination for acpi-cpufreq
http://bugzilla.kernel.org/show_bug.cgi?id=5737
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
index 3852d0a..4c7c6e08 100644
--- a/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
+++ b/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
@@ -48,12 +48,13 @@
struct cpufreq_acpi_io {
- struct acpi_processor_performance acpi_data;
+ 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 acpi_processor_performance *acpi_perf_data[NR_CPUS];
static struct cpufreq_driver acpi_cpufreq_driver;
@@ -104,64 +105,43 @@
{
u16 port = 0;
u8 bit_width = 0;
+ int i = 0;
int ret = 0;
u32 value = 0;
- int i = 0;
- struct cpufreq_freqs cpufreq_freqs;
- cpumask_t saved_mask;
int retval;
+ struct acpi_processor_performance *perf;
dprintk("acpi_processor_set_performance\n");
- /*
- * TBD: Use something other than set_cpus_allowed.
- * As set_cpus_allowed is a bit racy,
- * with any other set_cpus_allowed for this process.
- */
- saved_mask = current->cpus_allowed;
- set_cpus_allowed(current, cpumask_of_cpu(cpu));
- if (smp_processor_id() != cpu) {
- return (-EAGAIN);
- }
-
- if (state == data->acpi_data.state) {
+ retval = 0;
+ perf = data->acpi_data;
+ if (state == perf->state) {
if (unlikely(data->resume)) {
dprintk("Called after resume, resetting to P%d\n", state);
data->resume = 0;
} else {
dprintk("Already at target state (P%d)\n", state);
- retval = 0;
- goto migrate_end;
+ return (retval);
}
}
- dprintk("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);
+ dprintk("Transitioning from P%d to P%d\n", perf->state, state);
/*
* First we write the target state's 'control' value to the
* control_register.
*/
- port = data->acpi_data.control_register.address;
- bit_width = data->acpi_data.control_register.bit_width;
- value = (u32) data->acpi_data.states[state].control;
+ port = perf->control_register.address;
+ bit_width = perf->control_register.bit_width;
+ value = (u32) perf->states[state].control;
dprintk("Writing 0x%08x to port 0x%04x\n", value, port);
ret = acpi_processor_write_port(port, bit_width, value);
if (ret) {
dprintk("Invalid port width 0x%04x\n", bit_width);
- retval = ret;
- goto migrate_end;
+ return (ret);
}
/*
@@ -177,49 +157,36 @@
* before giving up.
*/
- port = data->acpi_data.status_register.address;
- bit_width = data->acpi_data.status_register.bit_width;
+ port = perf->status_register.address;
+ bit_width = perf->status_register.bit_width;
dprintk("Looking for 0x%08x from port 0x%04x\n",
- (u32) data->acpi_data.states[state].status, port);
+ (u32) perf->states[state].status, port);
- for (i=0; i<100; i++) {
+ for (i = 0; i < 100; i++) {
ret = acpi_processor_read_port(port, bit_width, &value);
if (ret) {
dprintk("Invalid port width 0x%04x\n", bit_width);
- retval = ret;
- goto migrate_end;
+ return (ret);
}
- if (value == (u32) data->acpi_data.states[state].status)
+ if (value == (u32) perf->states[state].status)
break;
udelay(10);
}
} else {
i = 0;
- value = (u32) data->acpi_data.states[state].status;
+ value = (u32) perf->states[state].status;
}
- /* notify cpufreq */
- cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE);
-
- if (unlikely(value != (u32) data->acpi_data.states[state].status)) {
- unsigned int tmp = cpufreq_freqs.new;
- cpufreq_freqs.new = cpufreq_freqs.old;
- cpufreq_freqs.old = tmp;
- cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_PRECHANGE);
- cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE);
+ if (unlikely(value != (u32) perf->states[state].status)) {
printk(KERN_WARNING "acpi-cpufreq: Transition failed\n");
retval = -ENODEV;
- goto migrate_end;
+ return (retval);
}
dprintk("Transition successful after %d microseconds\n", i * 10);
- data->acpi_data.state = state;
-
- retval = 0;
-migrate_end:
- set_cpus_allowed(current, saved_mask);
+ perf->state = state;
return (retval);
}
@@ -231,8 +198,17 @@
unsigned int relation)
{
struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu];
+ struct acpi_processor_performance *perf;
+ struct cpufreq_freqs freqs;
+ cpumask_t online_policy_cpus;
+ cpumask_t saved_mask;
+ cpumask_t set_mask;
+ cpumask_t covered_cpus;
+ unsigned int cur_state = 0;
unsigned int next_state = 0;
unsigned int result = 0;
+ unsigned int j;
+ unsigned int tmp;
dprintk("acpi_cpufreq_setpolicy\n");
@@ -241,11 +217,91 @@
target_freq,
relation,
&next_state);
- if (result)
+ if (unlikely(result))
return (result);
- result = acpi_processor_set_performance (data, policy->cpu, next_state);
+ perf = data->acpi_data;
+ cur_state = perf->state;
+ freqs.old = data->freq_table[cur_state].frequency;
+ freqs.new = data->freq_table[next_state].frequency;
+ /* cpufreq holds the hotplug lock, so we are safe from here on */
+ cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
+
+ for_each_cpu_mask(j, online_policy_cpus) {
+ freqs.cpu = j;
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+ }
+
+ /*
+ * We need to call driver->target() on all or any CPU in
+ * policy->cpus, depending on policy->shared_type.
+ */
+ saved_mask = current->cpus_allowed;
+ 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");
+ result = -EAGAIN;
+ break;
+ }
+
+ result = acpi_processor_set_performance (data, j, next_state);
+ if (result) {
+ result = -EAGAIN;
+ break;
+ }
+
+ if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
+ break;
+
+ cpu_set(j, covered_cpus);
+ }
+
+ for_each_cpu_mask(j, online_policy_cpus) {
+ freqs.cpu = j;
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+ }
+
+ if (unlikely(result)) {
+ /*
+ * We have failed halfway through the frequency change.
+ * We have sent callbacks to online_policy_cpus and
+ * acpi_processor_set_performance() has been called on
+ * coverd_cpus. Best effort undo..
+ */
+
+ if (!cpus_empty(covered_cpus)) {
+ for_each_cpu_mask(j, covered_cpus) {
+ policy->cpu = j;
+ acpi_processor_set_performance (data,
+ j,
+ cur_state);
+ }
+ }
+
+ 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 (result);
}
@@ -271,30 +327,65 @@
struct cpufreq_acpi_io *data,
unsigned int cpu)
{
+ struct acpi_processor_performance *perf = data->acpi_data;
+
if (cpu_khz) {
/* search the closest match to cpu_khz */
unsigned int i;
unsigned long freq;
- unsigned long freqn = data->acpi_data.states[0].core_frequency * 1000;
+ unsigned long freqn = perf->states[0].core_frequency * 1000;
- for (i=0; i < (data->acpi_data.state_count - 1); i++) {
+ for (i = 0; i < (perf->state_count - 1); i++) {
freq = freqn;
- freqn = data->acpi_data.states[i+1].core_frequency * 1000;
+ freqn = perf->states[i+1].core_frequency * 1000;
if ((2 * cpu_khz) > (freqn + freq)) {
- data->acpi_data.state = i;
+ perf->state = i;
return (freq);
}
}
- data->acpi_data.state = data->acpi_data.state_count - 1;
+ perf->state = perf->state_count - 1;
return (freqn);
- } else
+ } else {
/* assume CPU is at P0... */
- data->acpi_data.state = 0;
- return data->acpi_data.states[0].core_frequency * 1000;
-
+ perf->state = 0;
+ return perf->states[0].core_frequency * 1000;
+ }
}
+/*
+ * acpi_cpufreq_early_init - initialize ACPI P-States library
+ *
+ * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
+ * in order to determine correct frequency and voltage pairings. We can
+ * do _PDC and _PSD and find out the processor dependency for the
+ * actual init that will happen later...
+ */
+static int acpi_cpufreq_early_init_acpi(void)
+{
+ struct acpi_processor_performance *data;
+ unsigned int i, j;
+
+ dprintk("acpi_cpufreq_early_init\n");
+
+ 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;
+ }
+
+ /* Do initialization in ACPI core */
+ acpi_processor_preregister_performance(acpi_perf_data);
+ return 0;
+}
+
static int
acpi_cpufreq_cpu_init (
struct cpufreq_policy *policy)
@@ -304,41 +395,51 @@
struct cpufreq_acpi_io *data;
unsigned int result = 0;
struct cpuinfo_x86 *c = &cpu_data[policy->cpu];
+ struct acpi_processor_performance *perf;
dprintk("acpi_cpufreq_cpu_init\n");
+ if (!acpi_perf_data[cpu])
+ return (-ENODEV);
+
data = kzalloc(sizeof(struct cpufreq_acpi_io), GFP_KERNEL);
if (!data)
return (-ENOMEM);
+ data->acpi_data = acpi_perf_data[cpu];
acpi_io_data[cpu] = data;
- result = acpi_processor_register_performance(&data->acpi_data, cpu);
+ result = acpi_processor_register_performance(data->acpi_data, cpu);
if (result)
goto err_free;
+ perf = data->acpi_data;
+ policy->cpus = perf->shared_cpu_map;
+ policy->shared_type = perf->shared_type;
+
if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
}
/* capability check */
- if (data->acpi_data.state_count <= 1) {
+ if (perf->state_count <= 1) {
dprintk("No P-States\n");
result = -ENODEV;
goto err_unreg;
}
- if ((data->acpi_data.control_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO) ||
- (data->acpi_data.status_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO)) {
+
+ if ((perf->control_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO) ||
+ (perf->status_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO)) {
dprintk("Unsupported address space [%d, %d]\n",
- (u32) (data->acpi_data.control_register.space_id),
- (u32) (data->acpi_data.status_register.space_id));
+ (u32) (perf->control_register.space_id),
+ (u32) (perf->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);
+ data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) * (perf->state_count + 1), GFP_KERNEL);
if (!data->freq_table) {
result = -ENOMEM;
goto err_unreg;
@@ -346,9 +447,9 @@
/* 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;
+ for (i=0; i<perf->state_count; i++) {
+ if ((perf->states[i].transition_latency * 1000) > policy->cpuinfo.transition_latency)
+ policy->cpuinfo.transition_latency = perf->states[i].transition_latency * 1000;
}
policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
@@ -356,11 +457,11 @@
policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
/* table init */
- for (i=0; i<=data->acpi_data.state_count; i++)
+ for (i=0; i<=perf->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;
+ if (i<perf->state_count)
+ data->freq_table[i].frequency = perf->states[i].core_frequency * 1000;
else
data->freq_table[i].frequency = CPUFREQ_TABLE_END;
}
@@ -375,12 +476,12 @@
printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management activated.\n",
cpu);
- for (i = 0; i < data->acpi_data.state_count; i++)
+ for (i = 0; i < perf->state_count; i++)
dprintk(" %cP%d: %d MHz, %d mW, %d uS\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);
+ (i == perf->state?'*':' '), i,
+ (u32) perf->states[i].core_frequency,
+ (u32) perf->states[i].power,
+ (u32) perf->states[i].transition_latency);
cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
@@ -395,7 +496,7 @@
err_freqfree:
kfree(data->freq_table);
err_unreg:
- acpi_processor_unregister_performance(&data->acpi_data, cpu);
+ acpi_processor_unregister_performance(perf, cpu);
err_free:
kfree(data);
acpi_io_data[cpu] = NULL;
@@ -416,7 +517,7 @@
if (data) {
cpufreq_frequency_table_put_attr(policy->cpu);
acpi_io_data[policy->cpu] = NULL;
- acpi_processor_unregister_performance(&data->acpi_data, policy->cpu);
+ acpi_processor_unregister_performance(data->acpi_data, policy->cpu);
kfree(data);
}
@@ -462,7 +563,10 @@
dprintk("acpi_cpufreq_init\n");
- result = cpufreq_register_driver(&acpi_cpufreq_driver);
+ result = acpi_cpufreq_early_init_acpi();
+
+ if (!result)
+ result = cpufreq_register_driver(&acpi_cpufreq_driver);
return (result);
}
@@ -471,10 +575,15 @@
static void __exit
acpi_cpufreq_exit (void)
{
+ unsigned int i;
dprintk("acpi_cpufreq_exit\n");
cpufreq_unregister_driver(&acpi_cpufreq_driver);
+ for_each_cpu(i) {
+ kfree(acpi_perf_data[i]);
+ acpi_perf_data[i] = NULL;
+ }
return;
}