ACPI: processor: Introduce acpi_processor_evaluate_cst()

In order to separate the ACPI _CST evaluation from checks
specific to the ACPI processor driver, move the majority of
the acpi_processor_get_power_info_cst() function body to a new
function, acpi_processor_evaluate_cst(), that will extract
the C-states information from _CST output, and redefine
acpi_processor_get_power_info_cst() as a wrapper around it.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index dd737d836c031948882351b08687a290e0ccab6a..e92d0e6d4cd1446fc39061c4ce0e53414254db09 100644 (file)
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -297,21 +297,17 @@ static int acpi_processor_get_power_info_default(struct acpi_processor *pr)
        return 0;
 }
 
-static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
+static int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
+                                      struct acpi_processor_power *info)
 {
+       struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+       union acpi_object *cst;
        acpi_status status;
        u64 count;
-       int current_count;
+       int current_count = 0;
        int i, ret = 0;
-       struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
-       union acpi_object *cst;
-
-       if (nocst)
-               return -ENODEV;
 
-       current_count = 0;
-
-       status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer);
+       status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
        if (ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n"));
                return -ENODEV;
@@ -335,9 +331,6 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
                goto end;
        }
 
-       /* Tell driver that at least _CST is supported. */
-       pr->flags.has_cst = 1;
-
        for (i = 1; i <= count; i++) {
                union acpi_object *element;
                union acpi_object *obj;
@@ -383,7 +376,7 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
                cx.entry_method = ACPI_CSTATE_SYSTEMIO;
                if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
                        if (acpi_processor_ffh_cstate_probe
-                                       (pr->id, &cx, reg) == 0) {
+                                       (cpu, &cx, reg) == 0) {
                                cx.entry_method = ACPI_CSTATE_FFH;
                        } else if (cx.type == ACPI_STATE_C1) {
                                /*
@@ -432,7 +425,7 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
                        continue;
 
                current_count++;
-               memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx));
+               memcpy(&info->states[current_count], &cx, sizeof(cx));
 
                /*
                 * We support total ACPI_PROCESSOR_MAX_POWER - 1
@@ -446,12 +439,9 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
                }
        }
 
-       ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n",
-                         current_count));
+       acpi_handle_info(handle, "Found %d idle states\n", current_count);
 
-       /* Validate number of power states discovered */
-       if (current_count < 2)
-               ret = -EFAULT;
+       info->count = current_count;
 
       end:
        kfree(buffer.pointer);
@@ -459,6 +449,28 @@ static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
        return ret;
 }
 
+static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
+{
+       int ret;
+
+       if (nocst)
+               return -ENODEV;
+
+       ret = acpi_processor_evaluate_cst(pr->handle, pr->id, &pr->power);
+       if (ret)
+               return ret;
+
+       /*
+        * It is expected that there will be at least 2 states, C1 and
+        * something else (C2 or C3), so fail if that is not the case.
+        */
+       if (pr->power.count < 2)
+               return -EFAULT;
+
+       pr->flags.has_cst = 1;
+       return 0;
+}
+
 static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
                                           struct acpi_processor_cx *cx)
 {