[PATCH 066/112] ACPI : Update T-state coordination after getting _TSD info

Len Brown
2008-02-07T09:36:24Z

From: Zhao Yakui <yakui.zhao@intel.com>

Accordint to ACPI spec, the _TSD object provides T-state control cross
logical processor dependency information to OSPM.
After the _TSD data for all cpus are obtained, OSPM will set up
the T-state coordination between CPUs.

Of course if the _TSD doesn't exist or _TSD data is incorrect , it is
assumed that there is no T-state coordination and T-state is changed
independently.

Now there is no proper solution to update T-state coordination after
one cpu is hotplugged. So this patch won't support hotplugged cpu very well.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
---
drivers/acpi/processor_core.c | 2 +
drivers/acpi/processor_throttling.c | 180 ++++++++++++++++++++++++++++++++++-
include/acpi/processor.h | 4 +-
3 files changed, 184 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index e48ee4f..b3b5373 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -1061,6 +1061,8 @@ static int __init acpi_processor_init(void)

acpi_processor_ppc_init();

+ acpi_processor_throttling_init();
+
return 0;

out_cpuidle:
diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c
index 5d2eae2..d6780f4 100644
--- a/drivers/acpi/processor_throttling.c
+++ b/drivers/acpi/processor_throttling.c
@@ -48,6 +48,154 @@ ACPI_MODULE_NAME("processor_throttling");
static int acpi_processor_get_throttling(struct acpi_processor *pr);
int acpi_processor_set_throttling(struct acpi_processor *pr, int state);

+static int acpi_processor_update_tsd_coord(void)
+{
+ int count, count_target;
+ int retval = 0;
+ unsigned int i, j;
+ cpumask_t covered_cpus;
+ struct acpi_processor *pr, *match_pr;
+ struct acpi_tsd_package *pdomain, *match_pdomain;
+ struct acpi_processor_throttling *pthrottling, *match_pthrottling;
+
+ /*
+ * Now that we have _TSD data from all CPUs, lets setup T-state
+ * coordination among all CPUs.
+ */
+ for_each_possible_cpu(i) {
+ pr = processors[i];
+ if (!pr)
+ continue;
+
+ /* Basic validity check for domain info */
+ pthrottling = &(pr->throttling);
+
+ /*
+ * If tsd package for one cpu is invalid, the coordination
+ * among all CPUs is thought as invalid.
+ * Maybe it is ugly.
+ */
+ if (!pthrottling->tsd_valid_flag) {
+ retval = -EINVAL;
+ break;
+ }
+ }
+ if (retval)
+ goto err_ret;
+
+ cpus_clear(covered_cpus);
+ for_each_possible_cpu(i) {
+ pr = processors[i];
+ if (!pr)
+ continue;
+
+ if (cpu_isset(i, covered_cpus))
+ continue;
+ pthrottling = &pr->throttling;
+
+ pdomain = &(pthrottling->domain_info);
+ cpu_set(i, pthrottling->shared_cpu_map);
+ cpu_set(i, covered_cpus);
+ /*
+ * If the number of processor in the TSD domain is 1, it is
+ * unnecessary to parse the coordination for this CPU.
+ */
+ if (pdomain->num_processors <= 1)
+ continue;
+
+ /* Validate the Domain info */
+ count_target = pdomain->num_processors;
+ count = 1;
+
+ for_each_possible_cpu(j) {
+ if (i == j)
+ continue;
+
+ match_pr = processors[j];
+ if (!match_pr)
+ continue;
+
+ match_pthrottling = &(match_pr->throttling);
+ match_pdomain = &(match_pthrottling->domain_info);
+ if (match_pdomain->domain != pdomain->domain)
+ continue;
+
+ /* Here i and j are in the same domain.
+ * If two TSD packages have the same domain, they
+ * should have the same num_porcessors and
+ * coordination type. Otherwise it will be regarded
+ * as illegal.
+ */
+ if (match_pdomain->num_processors != count_target) {
+ retval = -EINVAL;
+ goto err_ret;
+ }
+
+ if (pdomain->coord_type != match_pdomain->coord_type) {
+ retval = -EINVAL;
+ goto err_ret;
+ }
+
+ cpu_set(j, covered_cpus);
+ cpu_set(j, pthrottling->shared_cpu_map);
+ count++;
+ }
+ for_each_possible_cpu(j) {
+ if (i == j)
+ continue;
+
+ match_pr = processors[j];
+ if (!match_pr)
+ continue;
+
+ match_pthrottling = &(match_pr->throttling);
+ match_pdomain = &(match_pthrottling->domain_info);
+ if (match_pdomain->domain != pdomain->domain)
+ continue;
+
+ /*
+ * If some CPUS have the same domain, they
+ * will have the same shared_cpu_map.
+ */
+ match_pthrottling->shared_cpu_map =
+ pthrottling->shared_cpu_map;
+ }
+ }
+
+err_ret:
+ for_each_possible_cpu(i) {
+ pr = processors[i];
+ if (!pr)
+ continue;
+
+ /*
+ * Assume no coordination on any error parsing domain info.
+ * The coordination type will be forced as SW_ALL.
+ */
+ if (retval) {
+ pthrottling = &(pr->throttling);
+ cpus_clear(pthrottling->shared_cpu_map);
+ cpu_set(i, pthrottling->shared_cpu_map);
+ pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
+ }
+ }
+
+ return retval;
+}
+
+/*
+ * Update the T-state coordination after the _TSD
+ * data for all cpus is obtained.
+ */
+void acpi_processor_throttling_init(void)
+{
+ if (acpi_processor_update_tsd_coord())
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Assume no T-state coordination\n"));
+
+ return;
+}
+
/*
* _TPC - Throttling Present Capabilities
*/
@@ -293,6 +441,10 @@ static int acpi_processor_get_tsd(struct acpi_processor *pr)
struct acpi_buffer state = { 0, NULL };
union acpi_object *tsd = NULL;
struct acpi_tsd_package *pdomain;
+ struct acpi_processor_throttling *pthrottling;
+
+ pthrottling = &pr->throttling;
+ pthrottling->tsd_valid_flag = 0;

status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
if (ACPI_FAILURE(status)) {
@@ -340,6 +492,22 @@ static int acpi_processor_get_tsd(struct acpi_processor *pr)
goto end;
}

+ pthrottling = &pr->throttling;
+ pthrottling->tsd_valid_flag = 1;
+ pthrottling->shared_type = pdomain->coord_type;
+ cpu_set(pr->id, pthrottling->shared_cpu_map);
+ /*
+ * If the coordination type is not defined in ACPI spec,
+ * the tsd_valid_flag will be clear and coordination type
+ * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
+ */
+ if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
+ pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
+ pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
+ pthrottling->tsd_valid_flag = 0;
+ pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
+ }
+
end:
kfree(buffer.pointer);
return result;
@@ -772,6 +940,7 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
int acpi_processor_get_throttling_info(struct acpi_processor *pr)
{
int result = 0;
+ struct acpi_processor_throttling *pthrottling;

ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
@@ -803,7 +972,16 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr)
&acpi_processor_set_throttling_ptc;
}

- acpi_processor_get_tsd(pr);
+ /*
+ * If TSD package for one CPU can't be parsed successfully, it means
+ * that this CPU will have no coordination with other CPUs.
+ */
+ if (acpi_processor_get_tsd(pr)) {
+ pthrottling = &pr->throttling;
+ pthrottling->tsd_valid_flag = 0;
+ cpu_set(pr->id, pthrottling->shared_cpu_map);
+ pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
+ }

/*
* PIIX4 Errata: We don't support throttling on the original PIIX4.
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 76411b1..d90ad0d 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -176,6 +176,8 @@ struct acpi_processor_throttling {
u32 address;
u8 duty_offset;
u8 duty_width;
+ u8 tsd_valid_flag;
+ unsigned int shared_type;
struct acpi_processor_tx states[ACPI_PROCESSOR_MAX_THROTTLING];
};

@@ -316,7 +318,7 @@ static inline int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
int acpi_processor_get_throttling_info(struct acpi_processor *pr);
extern int acpi_processor_set_throttling(struct acpi_processor *pr, int state);
extern struct file_operations acpi_processor_throttling_fops;
-
+extern void acpi_processor_throttling_init(void);
/* in processor_idle.c */
int acpi_processor_power_init(struct acpi_processor *pr,
struct acpi_device *device);
--
1.5.4.23.gef5b9