+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);
+
+/*
+ * _TPC - Throttling Present Capabilities
+ */
+static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
+{
+ acpi_status status = 0;
+ unsigned long tpc = 0;
+
+ if (!pr)
+ return -EINVAL;
+ status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &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;
+ return 0;
+}
+
+int acpi_processor_tstate_has_changed(struct acpi_processor *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 - Processor Throttling Control (and status) register location
+ */
+static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
+{
+ int result = 0;
+ acpi_status status = 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)) {
+ if (status != AE_NOT_FOUND) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
+ }
+ return -ENODEV;
+ }
+
+ ptc = (union acpi_object *)buffer.pointer;
+ if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
+ || (ptc->package.count != 2)) {
+ printk(KERN_ERR PREFIX "Invalid _PTC data\n");
+ result = -EFAULT;
+ goto end;
+ }
+
+ /*
+ * control_register
+ */
+
+ obj = ptc->package.elements[0];
+
+ if ((obj.type != ACPI_TYPE_BUFFER)
+ || (obj.buffer.length < sizeof(struct acpi_ptc_register))
+ || (obj.buffer.pointer == NULL)) {
+ printk(KERN_ERR PREFIX
+ "Invalid _PTC data (control_register)\n");
+ result = -EFAULT;
+ goto end;
+ }
+ memcpy(&pr->throttling.control_register, obj.buffer.pointer,
+ sizeof(struct acpi_ptc_register));
+
+ /*
+ * status_register
+ */
+
+ obj = ptc->package.elements[1];
+
+ if ((obj.type != ACPI_TYPE_BUFFER)
+ || (obj.buffer.length < sizeof(struct acpi_ptc_register))
+ || (obj.buffer.pointer == NULL)) {
+ printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
+ result = -EFAULT;
+ goto end;
+ }
+
+ 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;
+ acpi_status status = AE_OK;
+ struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+ struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
+ struct acpi_buffer state = { 0, NULL };
+ union acpi_object *tss = NULL;
+ int i;
+
+ status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
+ if (ACPI_FAILURE(status)) {
+ if (status != AE_NOT_FOUND) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
+ }
+ return -ENODEV;
+ }
+
+ tss = buffer.pointer;
+ if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
+ printk(KERN_ERR PREFIX "Invalid _TSS data\n");
+ result = -EFAULT;
+ goto end;
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
+ tss->package.count));
+
+ pr->throttling.state_count = tss->package.count;
+ pr->throttling.states_tss =
+ kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
+ GFP_KERNEL);
+ if (!pr->throttling.states_tss) {
+ result = -ENOMEM;
+ goto end;
+ }
+
+ for (i = 0; i < pr->throttling.state_count; i++) {
+
+ struct acpi_processor_tx_tss *tx =
+ (struct acpi_processor_tx_tss *)&(pr->throttling.
+ states_tss[i]);
+
+ state.length = sizeof(struct acpi_processor_tx_tss);
+ state.pointer = tx;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
+
+ status = acpi_extract_package(&(tss->package.elements[i]),
+ &format, &state);
+ if (ACPI_FAILURE(status)) {
+ ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
+ result = -EFAULT;
+ kfree(pr->throttling.states_tss);
+ goto end;
+ }
+
+ if (!tx->freqpercentage) {
+ printk(KERN_ERR PREFIX
+ "Invalid _TSS data: freq is zero\n");
+ result = -EFAULT;
+ kfree(pr->throttling.states_tss);
+ goto end;
+ }
+ }
+
+ end:
+ kfree(buffer.pointer);
+
+ return result;
+}
+
+/*
+ * _TSD - T-State Dependencies
+ */
+static int acpi_processor_get_tsd(struct acpi_processor *pr)
+{
+ int result = 0;
+ acpi_status status = AE_OK;
+ struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+ struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
+ struct acpi_buffer state = { 0, NULL };
+ union acpi_object *tsd = NULL;
+ struct acpi_tsd_package *pdomain;
+
+ 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;
+ }
+
+ tsd = buffer.pointer;
+ if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
+ result = -EFAULT;
+ goto end;
+ }
+
+ if (tsd->package.count != 1) {
+ ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
+ result = -EFAULT;
+ goto end;
+ }
+
+ pdomain = &(pr->throttling.domain_info);
+
+ state.length = sizeof(struct acpi_tsd_package);
+ state.pointer = pdomain;
+
+ status = acpi_extract_package(&(tsd->package.elements[0]),
+ &format, &state);
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
+ result = -EFAULT;
+ goto end;
+ }
+
+ if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
+ ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _TSD:num_entries\n"));
+ result = -EFAULT;
+ goto end;
+ }
+
+ if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
+ ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _TSD:revision\n"));
+ result = -EFAULT;
+ goto end;
+ }
+
+ end:
+ kfree(buffer.pointer);
+ return result;
+}