#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
+#include <linux/sched.h>
#include <linux/cpufreq.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
static int acpi_processor_get_throttling(struct acpi_processor *pr);
int acpi_processor_set_throttling(struct acpi_processor *pr, int state);
+/*
+ * _TPC - Throttling Present Capabilities
+ */
static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
{
acpi_status status = 0;
if (!pr)
return -EINVAL;
status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
- if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
- ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
+ if (ACPI_FAILURE(status)) {
+ if (status != AE_NOT_FOUND) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
+ }
return -ENODEV;
}
pr->throttling_platform_limit = (int)tpc;
int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
{
- return acpi_processor_get_platform_limit(pr);
+ int result = 0;
+ int throttling_limit;
+ int current_state;
+ struct acpi_processor_limit *limit;
+ int target_state;
+
+ result = acpi_processor_get_platform_limit(pr);
+ if (result) {
+ /* Throttling Limit is unsupported */
+ return result;
+ }
+
+ throttling_limit = pr->throttling_platform_limit;
+ if (throttling_limit >= pr->throttling.state_count) {
+ /* Uncorrect Throttling Limit */
+ return -EINVAL;
+ }
+
+ current_state = pr->throttling.state;
+ if (current_state > throttling_limit) {
+ /*
+ * The current state can meet the requirement of
+ * _TPC limit. But it is reasonable that OSPM changes
+ * t-states from high to low for better performance.
+ * Of course the limit condition of thermal
+ * and user should be considered.
+ */
+ limit = &pr->limit;
+ target_state = throttling_limit;
+ if (limit->thermal.tx > target_state)
+ target_state = limit->thermal.tx;
+ if (limit->user.tx > target_state)
+ target_state = limit->user.tx;
+ } else if (current_state == throttling_limit) {
+ /*
+ * Unnecessary to change the throttling state
+ */
+ return 0;
+ } else {
+ /*
+ * If the current state is lower than the limit of _TPC, it
+ * will be forced to switch to the throttling state defined
+ * by throttling_platfor_limit.
+ * Because the previous state meets with the limit condition
+ * of thermal and user, it is unnecessary to check it again.
+ */
+ target_state = throttling_limit;
+ }
+ return acpi_processor_set_throttling(pr, target_state);
}
-/* --------------------------------------------------------------------------
- _PTC, _TSS, _TSD support
- -------------------------------------------------------------------------- */
+/*
+ * _PTC - Processor Throttling Control (and status) register location
+ */
static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
{
int result = 0;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *ptc = NULL;
union acpi_object obj = { 0 };
+ struct acpi_processor_throttling *throttling;
status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
if (ACPI_FAILURE(status)) {
- ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
+ if (status != AE_NOT_FOUND) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
+ }
return -ENODEV;
}
memcpy(&pr->throttling.status_register, obj.buffer.pointer,
sizeof(struct acpi_ptc_register));
+ throttling = &pr->throttling;
+
+ if ((throttling->control_register.bit_width +
+ throttling->control_register.bit_offset) > 32) {
+ printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
+ result = -EFAULT;
+ goto end;
+ }
+
+ if ((throttling->status_register.bit_width +
+ throttling->status_register.bit_offset) > 32) {
+ printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
+ result = -EFAULT;
+ goto end;
+ }
+
end:
kfree(buffer.pointer);
return result;
}
+
+/*
+ * _TSS - Throttling Supported States
+ */
static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
{
int result = 0;
status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
if (ACPI_FAILURE(status)) {
- ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
+ if (status != AE_NOT_FOUND) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
+ }
return -ENODEV;
}
return result;
}
+
+/*
+ * _TSD - T-State Dependencies
+ */
static int acpi_processor_get_tsd(struct acpi_processor *pr)
{
int result = 0;
status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
if (ACPI_FAILURE(status)) {
+ if (status != AE_NOT_FOUND) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
+ }
return -ENODEV;
}
return 0;
}
-static int acpi_read_throttling_status(struct acpi_processor_throttling
- *throttling)
+#ifdef CONFIG_X86
+static int acpi_throttling_rdmsr(struct acpi_processor *pr,
+ acpi_integer * value)
+{
+ struct cpuinfo_x86 *c;
+ u64 msr_high, msr_low;
+ unsigned int cpu;
+ u64 msr = 0;
+ int ret = -1;
+
+ cpu = pr->id;
+ c = &cpu_data(cpu);
+
+ if ((c->x86_vendor != X86_VENDOR_INTEL) ||
+ !cpu_has(c, X86_FEATURE_ACPI)) {
+ printk(KERN_ERR PREFIX
+ "HARDWARE addr space,NOT supported yet\n");
+ } else {
+ msr_low = 0;
+ msr_high = 0;
+ rdmsr_safe(MSR_IA32_THERM_CONTROL,
+ (u32 *)&msr_low , (u32 *) &msr_high);
+ msr = (msr_high << 32) | msr_low;
+ *value = (acpi_integer) msr;
+ ret = 0;
+ }
+ return ret;
+}
+
+static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
+{
+ struct cpuinfo_x86 *c;
+ unsigned int cpu;
+ int ret = -1;
+ u64 msr;
+
+ cpu = pr->id;
+ c = &cpu_data(cpu);
+
+ if ((c->x86_vendor != X86_VENDOR_INTEL) ||
+ !cpu_has(c, X86_FEATURE_ACPI)) {
+ printk(KERN_ERR PREFIX
+ "HARDWARE addr space,NOT supported yet\n");
+ } else {
+ msr = value;
+ wrmsr_safe(MSR_IA32_THERM_CONTROL,
+ msr & 0xffffffff, msr >> 32);
+ ret = 0;
+ }
+ return ret;
+}
+#else
+static int acpi_throttling_rdmsr(struct acpi_processor *pr,
+ acpi_integer * value)
+{
+ printk(KERN_ERR PREFIX
+ "HARDWARE addr space,NOT supported yet\n");
+ return -1;
+}
+
+static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
+{
+ printk(KERN_ERR PREFIX
+ "HARDWARE addr space,NOT supported yet\n");
+ return -1;
+}
+#endif
+
+static int acpi_read_throttling_status(struct acpi_processor *pr,
+ acpi_integer *value)
{
- int value = -1;
+ u32 bit_width, bit_offset;
+ u64 ptc_value;
+ u64 ptc_mask;
+ struct acpi_processor_throttling *throttling;
+ int ret = -1;
+
+ throttling = &pr->throttling;
switch (throttling->status_register.space_id) {
case ACPI_ADR_SPACE_SYSTEM_IO:
+ ptc_value = 0;
+ bit_width = throttling->status_register.bit_width;
+ bit_offset = throttling->status_register.bit_offset;
+
acpi_os_read_port((acpi_io_address) throttling->status_register.
- address, &value,
- (u32) throttling->status_register.bit_width *
- 8);
+ address, (u32 *) &ptc_value,
+ (u32) (bit_width + bit_offset));
+ ptc_mask = (1 << bit_width) - 1;
+ *value = (acpi_integer) ((ptc_value >> bit_offset) & ptc_mask);
+ ret = 0;
break;
case ACPI_ADR_SPACE_FIXED_HARDWARE:
- printk(KERN_ERR PREFIX
- "HARDWARE addr space,NOT supported yet\n");
+ ret = acpi_throttling_rdmsr(pr, value);
break;
default:
printk(KERN_ERR PREFIX "Unknown addr space %d\n",
(u32) (throttling->status_register.space_id));
}
- return value;
+ return ret;
}
-static int acpi_write_throttling_state(struct acpi_processor_throttling
- *throttling, int value)
+static int acpi_write_throttling_state(struct acpi_processor *pr,
+ acpi_integer value)
{
+ u32 bit_width, bit_offset;
+ u64 ptc_value;
+ u64 ptc_mask;
+ struct acpi_processor_throttling *throttling;
int ret = -1;
+ throttling = &pr->throttling;
switch (throttling->control_register.space_id) {
case ACPI_ADR_SPACE_SYSTEM_IO:
+ bit_width = throttling->control_register.bit_width;
+ bit_offset = throttling->control_register.bit_offset;
+ ptc_mask = (1 << bit_width) - 1;
+ ptc_value = value & ptc_mask;
+
acpi_os_write_port((acpi_io_address) throttling->
- control_register.address, value,
- (u32) throttling->control_register.
- bit_width * 8);
+ control_register.address,
+ (u32) (ptc_value << bit_offset),
+ (u32) (bit_width + bit_offset));
ret = 0;
break;
case ACPI_ADR_SPACE_FIXED_HARDWARE:
- printk(KERN_ERR PREFIX
- "HARDWARE addr space,NOT supported yet\n");
+ ret = acpi_throttling_wrmsr(pr, value);
break;
default:
printk(KERN_ERR PREFIX "Unknown addr space %d\n",
return ret;
}
-static int acpi_get_throttling_state(struct acpi_processor *pr, int value)
+static int acpi_get_throttling_state(struct acpi_processor *pr,
+ acpi_integer value)
{
int i;
return i;
}
-static int acpi_get_throttling_value(struct acpi_processor *pr, int state)
+static int acpi_get_throttling_value(struct acpi_processor *pr,
+ int state, acpi_integer *value)
{
- int value = -1;
+ int ret = -1;
+
if (state >= 0 && state <= pr->throttling.state_count) {
struct acpi_processor_tx_tss *tx =
(struct acpi_processor_tx_tss *)&(pr->throttling.
states_tss[state]);
- value = tx->control;
+ *value = tx->control;
+ ret = 0;
}
- return value;
+ return ret;
}
static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
{
int state = 0;
- u32 value = 0;
+ int ret;
+ acpi_integer value;
if (!pr)
return -EINVAL;
return -ENODEV;
pr->throttling.state = 0;
- local_irq_disable();
- value = acpi_read_throttling_status(&pr->throttling);
- if (value >= 0) {
+
+ value = 0;
+ ret = acpi_read_throttling_status(pr, &value);
+ if (ret >= 0) {
state = acpi_get_throttling_state(pr, value);
pr->throttling.state = state;
}
- local_irq_enable();
return 0;
}
static int acpi_processor_get_throttling(struct acpi_processor *pr)
{
- return pr->throttling.acpi_processor_get_throttling(pr);
+ cpumask_t saved_mask;
+ int ret;
+
+ /*
+ * Migrate task to the cpu pointed by pr.
+ */
+ saved_mask = current->cpus_allowed;
+ set_cpus_allowed(current, cpumask_of_cpu(pr->id));
+ ret = pr->throttling.acpi_processor_get_throttling(pr);
+ /* restore the previous state */
+ set_cpus_allowed(current, saved_mask);
+
+ return ret;
+}
+
+static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
+{
+ int i, step;
+
+ if (!pr->throttling.address) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
+ return -EINVAL;
+ } else if (!pr->throttling.duty_width) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
+ return -EINVAL;
+ }
+ /* TBD: Support duty_cycle values that span bit 4. */
+ else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
+ printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
+ return -EINVAL;
+ }
+
+ pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
+
+ /*
+ * Compute state values. Note that throttling displays a linear power
+ * performance relationship (at 50% performance the CPU will consume
+ * 50% power). Values are in 1/10th of a percent to preserve accuracy.
+ */
+
+ step = (1000 / pr->throttling.state_count);
+
+ for (i = 0; i < pr->throttling.state_count; i++) {
+ pr->throttling.states[i].performance = 1000 - step * i;
+ pr->throttling.states[i].power = 1000 - step * i;
+ }
+ return 0;
}
static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
int state)
{
- u32 value = 0;
+ int ret;
+ acpi_integer value;
if (!pr)
return -EINVAL;
if (state < pr->throttling_platform_limit)
return -EPERM;
- local_irq_disable();
-
- value = acpi_get_throttling_value(pr, state);
- if (value >= 0) {
- acpi_write_throttling_state(&pr->throttling, value);
+ value = 0;
+ ret = acpi_get_throttling_value(pr, state, &value);
+ if (ret >= 0) {
+ acpi_write_throttling_state(pr, value);
pr->throttling.state = state;
}
- local_irq_enable();
return 0;
}
int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
{
- return pr->throttling.acpi_processor_set_throttling(pr, state);
+ cpumask_t saved_mask;
+ int ret;
+ /*
+ * Migrate task to the cpu pointed by pr.
+ */
+ saved_mask = current->cpus_allowed;
+ set_cpus_allowed(current, cpumask_of_cpu(pr->id));
+ ret = pr->throttling.acpi_processor_set_throttling(pr, state);
+ /* restore the previous state */
+ set_cpus_allowed(current, saved_mask);
+ return ret;
}
int acpi_processor_get_throttling_info(struct acpi_processor *pr)
{
int result = 0;
- int step = 0;
- int i = 0;
- int no_ptc = 0;
- int no_tss = 0;
- int no_tsd = 0;
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
if (!pr)
return -EINVAL;
- /* TBD: Support ACPI 2.0 objects */
- no_ptc = acpi_processor_get_throttling_control(pr);
- no_tss = acpi_processor_get_throttling_states(pr);
- no_tsd = acpi_processor_get_tsd(pr);
-
- if (no_ptc || no_tss) {
+ /*
+ * Evaluate _PTC, _TSS and _TPC
+ * They must all be present or none of them can be used.
+ */
+ if (acpi_processor_get_throttling_control(pr) ||
+ acpi_processor_get_throttling_states(pr) ||
+ acpi_processor_get_platform_limit(pr))
+ {
pr->throttling.acpi_processor_get_throttling =
&acpi_processor_get_throttling_fadt;
pr->throttling.acpi_processor_set_throttling =
&acpi_processor_set_throttling_fadt;
+ if (acpi_processor_get_fadt_info(pr))
+ return 0;
} else {
pr->throttling.acpi_processor_get_throttling =
&acpi_processor_get_throttling_ptc;
&acpi_processor_set_throttling_ptc;
}
- if (!pr->throttling.address) {
- ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
- return 0;
- } else if (!pr->throttling.duty_width) {
- ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
- return 0;
- }
- /* TBD: Support duty_cycle values that span bit 4. */
- else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
- printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
- return 0;
- }
+ acpi_processor_get_tsd(pr);
/*
* PIIX4 Errata: We don't support throttling on the original PIIX4.
return 0;
}
- pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
-
- /*
- * Compute state values. Note that throttling displays a linear power/
- * performance relationship (at 50% performance the CPU will consume
- * 50% power). Values are in 1/10th of a percent to preserve accuracy.
- */
-
- step = (1000 / pr->throttling.state_count);
-
- for (i = 0; i < pr->throttling.state_count; i++) {
- pr->throttling.states[i].performance = step * i;
- pr->throttling.states[i].power = step * i;
- }
-
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
pr->throttling.state_count));
pr->throttling.state_count - 1);
seq_puts(seq, "states:\n");
- if (acpi_processor_get_throttling == acpi_processor_get_throttling_fadt)
+ if (pr->throttling.acpi_processor_get_throttling ==
+ acpi_processor_get_throttling_fadt) {
for (i = 0; i < pr->throttling.state_count; i++)
seq_printf(seq, " %cT%d: %02d%%\n",
(i == pr->throttling.state ? '*' : ' '), i,
(pr->throttling.states[i].performance ? pr->
throttling.states[i].performance / 10 : 0));
- else
+ } else {
for (i = 0; i < pr->throttling.state_count; i++)
seq_printf(seq, " %cT%d: %02d%%\n",
(i == pr->throttling.state ? '*' : ' '), i,
(int)pr->throttling.states_tss[i].
freqpercentage);
+ }
end:
return 0;
projects / linux-2.6 / blobdiff