Add PSCI service specific per-CPU data

This patch adds a structure defined by the PSCI service to the per-CPU data
array. The structure is used to save the 'power_state' parameter specified
during a 'cpu_suspend' call on the current CPU. This parameter was being saved
in the cpu node in the PSCI topology tree earlier.

The existing API to return the state id specified during a PSCI CPU_SUSPEND call
i.e. psci_get_suspend_stateid(mpidr) has been renamed to
psci_get_suspend_stateid_by_mpidr(mpidr). The new psci_get_suspend_stateid() API
returns the state id of the current cpu.

The psci_get_suspend_afflvl() API has been changed to return the target affinity
level of the current CPU. This was specified using the 'mpidr' parameter in the
old implementation.

The behaviour of the get_power_on_target_afflvl() has been tweaked such that
traversal of the PSCI topology tree to locate the affinity instance node for the
current CPU is done only in the debug build as it is an expensive operation.

Change-Id: Iaad49db75abda471f6a82d697ee6e0df554c4caf

1 files changed, 22 insertions, 20 deletions

diff --git a/services/std_svc/psci/psci_common.c b/services/std_svc/psci/psci_common.c
index 2fd1764c..9daf6f04 100644
--- a/services/std_svc/psci/psci_common.c
+++ b/services/std_svc/psci/psci_common.c
@@ -61,37 +61,39 @@ const plat_pm_ops_t *psci_plat_pm_ops;
 /*******************************************************************************
  * Routine to return the maximum affinity level to traverse to after a cpu has
  * been physically powered up. It is expected to be called immediately after
- * reset from assembler code. It has to find its 'aff_map_node' instead of
- * getting it as an argument.
- * TODO: Calling psci_get_aff_map_node() with the MMU disabled is slow. Add
- * support to allow faster access to the target affinity level.
+ * reset from assembler code.
  ******************************************************************************/
-int get_power_on_target_afflvl(unsigned long mpidr)
+int get_power_on_target_afflvl()
 {
-	aff_map_node_t *node;
-	unsigned int state;
 	int afflvl;
 
+#if DEBUG
+	unsigned int state;
+	aff_map_node_t *node;
+
 	/* Retrieve our node from the topology tree */
-	node = psci_get_aff_map_node(mpidr & MPIDR_AFFINITY_MASK,
-			MPIDR_AFFLVL0);
+	node = psci_get_aff_map_node(read_mpidr_el1() & MPIDR_AFFINITY_MASK,
+				     MPIDR_AFFLVL0);
 	assert(node);
 
 	/*
-	 * Return the maximum supported affinity level if this cpu was off.
-	 * Call the handler in the suspend code if this cpu had been suspended.
-	 * Any other state is invalid.
+	 * Sanity check the state of the cpu. It should be either suspend or "on
+	 * pending"
 	 */
 	state = psci_get_state(node);
-	if (state == PSCI_STATE_ON_PENDING)
-		return get_max_afflvl();
+	assert(state == PSCI_STATE_SUSPEND || state == PSCI_STATE_ON_PENDING);
+#endif
 
-	if (state == PSCI_STATE_SUSPEND) {
-		afflvl = psci_get_aff_map_node_suspend_afflvl(node);
-		assert(afflvl != PSCI_INVALID_DATA);
-		return afflvl;
-	}
-	return PSCI_E_INVALID_PARAMS;
+	/*
+	 * Assume that this cpu was suspended and retrieve its target affinity
+	 * level. If it is invalid then it could only have been turned off
+	 * earlier. get_max_afflvl() will return the highest affinity level a
+	 * cpu can be turned off to.
+	 */
+	afflvl = psci_get_suspend_afflvl();
+	if (afflvl == PSCI_INVALID_DATA)
+		afflvl = get_max_afflvl();
+	return afflvl;
 }
 
 /*******************************************************************************