Save 'power_state' early in PSCI CPU_SUSPEND call

This patch adds support to save the "power state" parameter before the
affinity level specific handlers are called in a CPU_SUSPEND call.
This avoids the need to pass the power_state as a parameter to the
handlers and Secure Payload Dispatcher (SPD) suspend spd_pm_ops.
The power_state arguments in the spd_pm_ops operations are now reserved
and must not be used. The SPD can query the relevant power_state fields
by using the psci_get_suspend_afflvl() & psci_get_suspend_stateid() APIs.

NOTE: THIS PATCH WILL BREAK THE SPD_PM_OPS INTERFACE. HENCE THE SECURE
PAYLOAD DISPATCHERS WILL NEED TO BE REWORKED TO USE THE NEW INTERFACE.

Change-Id: I1293d7dc8cf29cfa6a086a009eee41bcbf2f238e
diff --git a/bl32/tsp/tsp_main.c b/bl32/tsp/tsp_main.c
index 2eaca7c..c6000e1 100644
--- a/bl32/tsp/tsp_main.c
+++ b/bl32/tsp/tsp_main.c
@@ -216,7 +216,7 @@
  * this cpu's architectural state is saved in response to an earlier psci
  * cpu_suspend request.
  ******************************************************************************/
-tsp_args_t *tsp_cpu_suspend_main(uint64_t power_state,
+tsp_args_t *tsp_cpu_suspend_main(uint64_t arg0,
 			       uint64_t arg1,
 			       uint64_t arg2,
 			       uint64_t arg3,
@@ -242,8 +242,6 @@
 
 #if LOG_LEVEL >= LOG_LEVEL_INFO
 	spin_lock(&console_lock);
-	INFO("TSP: cpu 0x%x suspend request. power state: 0x%x\n",
-		mpidr, power_state);
 	INFO("TSP: cpu 0x%x: %d smcs, %d erets %d cpu suspend requests\n",
 		mpidr,
 		tsp_stats[linear_id].smc_count,
diff --git a/include/bl31/services/psci.h b/include/bl31/services/psci.h
index 26b607c..7513326 100644
--- a/include/bl31/services/psci.h
+++ b/include/bl31/services/psci.h
@@ -186,7 +186,7 @@
 typedef struct spd_pm_ops {
 	void (*svc_on)(uint64_t target_cpu);
 	int32_t (*svc_off)(uint64_t __unused);
-	void (*svc_suspend)(uint64_t power_state);
+	void (*svc_suspend)(uint64_t __unused);
 	void (*svc_on_finish)(uint64_t __unused);
 	void (*svc_suspend_finish)(uint64_t suspend_level);
 	void (*svc_migrate)(uint64_t __unused1, uint64_t __unused2);
diff --git a/services/spd/opteed/opteed_pm.c b/services/spd/opteed/opteed_pm.c
index 552d7a0..37419ec 100644
--- a/services/spd/opteed/opteed_pm.c
+++ b/services/spd/opteed/opteed_pm.c
@@ -48,7 +48,7 @@
  * This cpu is being turned off. Allow the OPTEED/OPTEE to perform any actions
  * needed
  ******************************************************************************/
-static int32_t opteed_cpu_off_handler(uint64_t cookie)
+static int32_t opteed_cpu_off_handler(uint64_t unused)
 {
 	int32_t rc = 0;
 	uint64_t mpidr = read_mpidr();
@@ -82,7 +82,7 @@
  * This cpu is being suspended. S-EL1 state must have been saved in the
  * resident cpu (mpidr format) if it is a UP/UP migratable OPTEE.
  ******************************************************************************/
-static void opteed_cpu_suspend_handler(uint64_t power_state)
+static void opteed_cpu_suspend_handler(uint64_t unused)
 {
 	int32_t rc = 0;
 	uint64_t mpidr = read_mpidr();
@@ -92,10 +92,7 @@
 	assert(optee_vectors);
 	assert(get_optee_pstate(optee_ctx->state) == OPTEE_PSTATE_ON);
 
-	/* Program the entry point, power_state parameter and enter OPTEE */
-	write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx),
-		      CTX_GPREG_X0,
-		      power_state);
+	/* Program the entry point and enter OPTEE */
 	cm_set_elr_el3(SECURE, (uint64_t) &optee_vectors->cpu_suspend_entry);
 	rc = opteed_synchronous_sp_entry(optee_ctx);
 
@@ -116,7 +113,7 @@
  * after initialising minimal architectural state that guarantees safe
  * execution.
  ******************************************************************************/
-static void opteed_cpu_on_finish_handler(uint64_t cookie)
+static void opteed_cpu_on_finish_handler(uint64_t unused)
 {
 	int32_t rc = 0;
 	uint64_t mpidr = read_mpidr();
diff --git a/services/spd/tspd/tspd_pm.c b/services/spd/tspd/tspd_pm.c
index 1655285..17abaea 100644
--- a/services/spd/tspd/tspd_pm.c
+++ b/services/spd/tspd/tspd_pm.c
@@ -49,7 +49,7 @@
  * This cpu is being turned off. Allow the TSPD/TSP to perform any actions
  * needed
  ******************************************************************************/
-static int32_t tspd_cpu_off_handler(uint64_t cookie)
+static int32_t tspd_cpu_off_handler(uint64_t unused)
 {
 	int32_t rc = 0;
 	uint64_t mpidr = read_mpidr();
@@ -83,7 +83,7 @@
  * This cpu is being suspended. S-EL1 state must have been saved in the
  * resident cpu (mpidr format) if it is a UP/UP migratable TSP.
  ******************************************************************************/
-static void tspd_cpu_suspend_handler(uint64_t power_state)
+static void tspd_cpu_suspend_handler(uint64_t unused)
 {
 	int32_t rc = 0;
 	uint64_t mpidr = read_mpidr();
@@ -93,10 +93,7 @@
 	assert(tsp_vectors);
 	assert(get_tsp_pstate(tsp_ctx->state) == TSP_PSTATE_ON);
 
-	/* Program the entry point, power_state parameter and enter the TSP */
-	write_ctx_reg(get_gpregs_ctx(&tsp_ctx->cpu_ctx),
-		      CTX_GPREG_X0,
-		      power_state);
+	/* Program the entry point and enter the TSP */
 	cm_set_elr_el3(SECURE, (uint64_t) &tsp_vectors->cpu_suspend_entry);
 	rc = tspd_synchronous_sp_entry(tsp_ctx);
 
@@ -117,7 +114,7 @@
  * after initialising minimal architectural state that guarantees safe
  * execution.
  ******************************************************************************/
-static void tspd_cpu_on_finish_handler(uint64_t cookie)
+static void tspd_cpu_on_finish_handler(uint64_t unused)
 {
 	int32_t rc = 0;
 	uint64_t mpidr = read_mpidr();
diff --git a/services/std_svc/psci/psci_afflvl_suspend.c b/services/std_svc/psci/psci_afflvl_suspend.c
index 4988e67..942e9a1 100644
--- a/services/std_svc/psci/psci_afflvl_suspend.c
+++ b/services/std_svc/psci/psci_afflvl_suspend.c
@@ -40,8 +40,7 @@
 #include <stddef.h>
 #include "psci_private.h"
 
-typedef int (*afflvl_suspend_handler_t)(aff_map_node_t *node,
-				      unsigned int power_state);
+typedef int (*afflvl_suspend_handler_t)(aff_map_node_t *node);
 
 /*******************************************************************************
  * This function saves the power state parameter passed in the current PSCI
@@ -103,17 +102,13 @@
  * The next three functions implement a handler for each supported affinity
  * level which is called when that affinity level is about to be suspended.
  ******************************************************************************/
-static int psci_afflvl0_suspend(aff_map_node_t *cpu_node,
-				unsigned int power_state)
+static int psci_afflvl0_suspend(aff_map_node_t *cpu_node)
 {
 	unsigned long psci_entrypoint;
 
 	/* Sanity check to safeguard against data corruption */
 	assert(cpu_node->level == MPIDR_AFFLVL0);
 
-	/* Save PSCI power state parameter for the core in suspend context */
-	psci_set_suspend_power_state(power_state);
-
 	/*
 	 * Generic management: Allow the Secure world to suspend itself
 	 */
@@ -124,8 +119,7 @@
 	 * error, it's expected to assert within
 	 */
 	if (psci_spd_pm && psci_spd_pm->svc_suspend)
-		psci_spd_pm->svc_suspend(power_state);
-
+		psci_spd_pm->svc_suspend(0);
 
 	/* Set the secure world (EL3) re-entry point after BL1 */
 	psci_entrypoint = (unsigned long) psci_aff_suspend_finish_entry;
@@ -150,8 +144,7 @@
 						 psci_get_phys_state(cpu_node));
 }
 
-static int psci_afflvl1_suspend(aff_map_node_t *cluster_node,
-				unsigned int power_state)
+static int psci_afflvl1_suspend(aff_map_node_t *cluster_node)
 {
 	unsigned int plat_state;
 	unsigned long psci_entrypoint;
@@ -184,8 +177,7 @@
 }
 
 
-static int psci_afflvl2_suspend(aff_map_node_t *system_node,
-				unsigned int power_state)
+static int psci_afflvl2_suspend(aff_map_node_t *system_node)
 {
 	unsigned int plat_state;
 	unsigned long psci_entrypoint;
@@ -238,8 +230,7 @@
  ******************************************************************************/
 static int psci_call_suspend_handlers(aff_map_node_t *mpidr_nodes[],
 				      int start_afflvl,
-				      int end_afflvl,
-				      unsigned int power_state)
+				      int end_afflvl)
 {
 	int rc = PSCI_E_INVALID_PARAMS, level;
 	aff_map_node_t *node;
@@ -254,8 +245,7 @@
 		 * of restoring what we might have torn down at
 		 * lower affinity levels.
 		 */
-		rc = psci_afflvl_suspend_handlers[level](node,
-							 power_state);
+		rc = psci_afflvl_suspend_handlers[level](node);
 		if (rc != PSCI_E_SUCCESS)
 			break;
 	}
@@ -283,7 +273,6 @@
  * first.
  ******************************************************************************/
 int psci_afflvl_suspend(entry_point_info_t *ep,
-			unsigned int power_state,
 			int start_afflvl,
 			int end_afflvl)
 {
@@ -339,8 +328,7 @@
 	/* Perform generic, architecture and platform specific handling */
 	rc = psci_call_suspend_handlers(mpidr_nodes,
 					start_afflvl,
-					end_afflvl,
-					power_state);
+					end_afflvl);
 
 	/*
 	 * Invalidate the entry for the highest affinity level stashed earlier.
diff --git a/services/std_svc/psci/psci_main.c b/services/std_svc/psci/psci_main.c
index 7fce5fa..506f592 100644
--- a/services/std_svc/psci/psci_main.c
+++ b/services/std_svc/psci/psci_main.c
@@ -125,18 +125,23 @@
 	if (rc != PSCI_E_SUCCESS)
 		return rc;
 
+	/* Save PSCI power state parameter for the core in suspend context */
+	psci_set_suspend_power_state(power_state);
+
 	/*
 	 * Do what is needed to enter the power down state. Upon success,
 	 * enter the final wfi which will power down this cpu else return
 	 * an error.
 	 */
 	rc = psci_afflvl_suspend(&ep,
-				 power_state,
 				 MPIDR_AFFLVL0,
 				 target_afflvl);
 	if (rc == PSCI_E_SUCCESS)
 		psci_power_down_wfi();
 	assert(rc == PSCI_E_INVALID_PARAMS);
+
+	/* Reset PSCI power state parameter for the core. */
+	psci_set_suspend_power_state(PSCI_INVALID_DATA);
 	return rc;
 }
 
diff --git a/services/std_svc/psci/psci_private.h b/services/std_svc/psci/psci_private.h
index 3a4ee3c..98d5d92 100644
--- a/services/std_svc/psci/psci_private.h
+++ b/services/std_svc/psci/psci_private.h
@@ -139,7 +139,6 @@
 
 /* Private exported functions from psci_affinity_suspend.c */
 int psci_afflvl_suspend(entry_point_info_t *ep,
-			unsigned int power_state,
 			int start_afflvl,
 			int end_afflvl);