Rework internal API to save non-secure entry point info

This patch replaces the internal psci_save_ns_entry() API with a
psci_get_ns_ep_info() API. The new function splits the work done by the
previous one such that it populates and returns an 'entry_point_info_t'
structure with the information to enter the normal world upon completion
of the CPU_SUSPEND or CPU_ON call. This information is used to populate
the non-secure context structure separately.

This allows the new internal API `psci_get_ns_ep_info` to return error
and enable the code to return safely.

Change-Id: Ifd87430a4a3168eac0ebac712f59c93cbad1b231

5 files changed, 67 insertions, 98 deletions

diff --git a/services/std_svc/psci/psci_afflvl_on.c b/services/std_svc/psci/psci_afflvl_on.c
index 04529d2f..b778c5ee 100644
--- a/services/std_svc/psci/psci_afflvl_on.c
+++ b/services/std_svc/psci/psci_afflvl_on.c
@@ -40,9 +40,7 @@
 #include "psci_private.h"
 
 typedef int (*afflvl_on_handler_t)(unsigned long target_cpu,
-				 aff_map_node_t *node,
-				 unsigned long ns_entrypoint,
-				 unsigned long context_id);
+				 aff_map_node_t *node);
 
 /*******************************************************************************
  * This function checks whether a cpu which has been requested to be turned on
@@ -66,14 +64,9 @@ static int cpu_on_validate_state(unsigned int psci_state)
  * TODO: Split this code across separate handlers for each type of setup?
  ******************************************************************************/
 static int psci_afflvl0_on(unsigned long target_cpu,
-			   aff_map_node_t *cpu_node,
-			   unsigned long ns_entrypoint,
-			   unsigned long context_id)
+			   aff_map_node_t *cpu_node)
 {
 	unsigned long psci_entrypoint;
-	uint32_t ns_scr_el3 = read_scr_el3();
-	uint32_t ns_sctlr_el1 = read_sctlr_el1();
-	int rc;
 
 	/* Sanity check to safeguard against data corruption */
 	assert(cpu_node->level == MPIDR_AFFLVL0);
@@ -86,16 +79,6 @@ static int psci_afflvl0_on(unsigned long target_cpu,
 	if (psci_spd_pm && psci_spd_pm->svc_on)
 		psci_spd_pm->svc_on(target_cpu);
 
-	/*
-	 * Arch. management: Derive the re-entry information for
-	 * the non-secure world from the non-secure state from
-	 * where this call originated.
-	 */
-	rc = psci_save_ns_entry(target_cpu, ns_entrypoint, context_id,
-				ns_scr_el3, ns_sctlr_el1);
-	if (rc != PSCI_E_SUCCESS)
-		return rc;
-
 	/* Set the secure world (EL3) re-entry point after BL1 */
 	psci_entrypoint = (unsigned long) psci_aff_on_finish_entry;
 
@@ -119,9 +102,7 @@ static int psci_afflvl0_on(unsigned long target_cpu,
  * TODO: Split this code across separate handlers for each type of setup?
  ******************************************************************************/
 static int psci_afflvl1_on(unsigned long target_cpu,
-			   aff_map_node_t *cluster_node,
-			   unsigned long ns_entrypoint,
-			   unsigned long context_id)
+			   aff_map_node_t *cluster_node)
 {
 	unsigned long psci_entrypoint;
 
@@ -155,9 +136,7 @@ static int psci_afflvl1_on(unsigned long target_cpu,
  * TODO: Split this code across separate handlers for each type of setup?
  ******************************************************************************/
 static int psci_afflvl2_on(unsigned long target_cpu,
-			   aff_map_node_t *system_node,
-			   unsigned long ns_entrypoint,
-			   unsigned long context_id)
+			   aff_map_node_t *system_node)
 {
 	unsigned long psci_entrypoint;
 
@@ -201,9 +180,7 @@ static const afflvl_on_handler_t psci_afflvl_on_handlers[] = {
 static int psci_call_on_handlers(aff_map_node_t *target_cpu_nodes[],
 				 int start_afflvl,
 				 int end_afflvl,
-				 unsigned long target_cpu,
-				 unsigned long entrypoint,
-				 unsigned long context_id)
+				 unsigned long target_cpu)
 {
 	int rc = PSCI_E_INVALID_PARAMS, level;
 	aff_map_node_t *node;
@@ -219,9 +196,7 @@ static int psci_call_on_handlers(aff_map_node_t *target_cpu_nodes[],
 		 * affinity levels.
 		 */
 		rc = psci_afflvl_on_handlers[level](target_cpu,
-						    node,
-						    entrypoint,
-						    context_id);
+						    node);
 		if (rc != PSCI_E_SUCCESS)
 			break;
 	}
@@ -246,8 +221,7 @@ static int psci_call_on_handlers(aff_map_node_t *target_cpu_nodes[],
  * first.
  ******************************************************************************/
 int psci_afflvl_on(unsigned long target_cpu,
-		   unsigned long entrypoint,
-		   unsigned long context_id,
+		   entry_point_info_t *ep,
 		   int start_afflvl,
 		   int end_afflvl)
 {
@@ -290,20 +264,23 @@ int psci_afflvl_on(unsigned long target_cpu,
 	rc = psci_call_on_handlers(target_cpu_nodes,
 				   start_afflvl,
 				   end_afflvl,
-				   target_cpu,
-				   entrypoint,
-				   context_id);
+				   target_cpu);
 
 	/*
 	 * This function updates the state of each affinity instance
 	 * corresponding to the mpidr in the range of affinity levels
 	 * specified.
 	 */
-	if (rc == PSCI_E_SUCCESS)
+	if (rc == PSCI_E_SUCCESS) {
 		psci_do_afflvl_state_mgmt(start_afflvl,
 					  end_afflvl,
 					  target_cpu_nodes,
 					  PSCI_STATE_ON_PENDING);
+		/*
+		 * Store the re-entry information for the non-secure world.
+		 */
+		cm_init_context(target_cpu, ep);
+	}
 
 exit:
 	/*
diff --git a/services/std_svc/psci/psci_afflvl_suspend.c b/services/std_svc/psci/psci_afflvl_suspend.c
index d30bf399..4988e677 100644
--- a/services/std_svc/psci/psci_afflvl_suspend.c
+++ b/services/std_svc/psci/psci_afflvl_suspend.c
@@ -41,8 +41,6 @@
 #include "psci_private.h"
 
 typedef int (*afflvl_suspend_handler_t)(aff_map_node_t *node,
-				      unsigned long ns_entrypoint,
-				      unsigned long context_id,
 				      unsigned int power_state);
 
 /*******************************************************************************
@@ -106,14 +104,9 @@ int psci_get_suspend_stateid_by_mpidr(unsigned long mpidr)
  * 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 long ns_entrypoint,
-				unsigned long context_id,
 				unsigned int power_state)
 {
 	unsigned long psci_entrypoint;
-	uint32_t ns_scr_el3 = read_scr_el3();
-	uint32_t ns_sctlr_el1 = read_sctlr_el1();
-	int rc;
 
 	/* Sanity check to safeguard against data corruption */
 	assert(cpu_node->level == MPIDR_AFFLVL0);
@@ -122,8 +115,7 @@ static int psci_afflvl0_suspend(aff_map_node_t *cpu_node,
 	psci_set_suspend_power_state(power_state);
 
 	/*
-	 * Generic management: Store the re-entry information for the non-secure
-	 * world and allow the secure world to suspend itself
+	 * Generic management: Allow the Secure world to suspend itself
 	 */
 
 	/*
@@ -134,14 +126,6 @@ static int psci_afflvl0_suspend(aff_map_node_t *cpu_node,
 	if (psci_spd_pm && psci_spd_pm->svc_suspend)
 		psci_spd_pm->svc_suspend(power_state);
 
-	/*
-	 * Generic management: Store the re-entry information for the
-	 * non-secure world
-	 */
-	rc = psci_save_ns_entry(read_mpidr_el1(), ns_entrypoint, context_id,
-				ns_scr_el3, ns_sctlr_el1);
-	if (rc != PSCI_E_SUCCESS)
-		return rc;
 
 	/* Set the secure world (EL3) re-entry point after BL1 */
 	psci_entrypoint = (unsigned long) psci_aff_suspend_finish_entry;
@@ -167,8 +151,6 @@ static int psci_afflvl0_suspend(aff_map_node_t *cpu_node,
 }
 
 static int psci_afflvl1_suspend(aff_map_node_t *cluster_node,
-				unsigned long ns_entrypoint,
-				unsigned long context_id,
 				unsigned int power_state)
 {
 	unsigned int plat_state;
@@ -203,8 +185,6 @@ static int psci_afflvl1_suspend(aff_map_node_t *cluster_node,
 
 
 static int psci_afflvl2_suspend(aff_map_node_t *system_node,
-				unsigned long ns_entrypoint,
-				unsigned long context_id,
 				unsigned int power_state)
 {
 	unsigned int plat_state;
@@ -259,8 +239,6 @@ static const afflvl_suspend_handler_t psci_afflvl_suspend_handlers[] = {
 static int psci_call_suspend_handlers(aff_map_node_t *mpidr_nodes[],
 				      int start_afflvl,
 				      int end_afflvl,
-				      unsigned long entrypoint,
-				      unsigned long context_id,
 				      unsigned int power_state)
 {
 	int rc = PSCI_E_INVALID_PARAMS, level;
@@ -277,8 +255,6 @@ static int psci_call_suspend_handlers(aff_map_node_t *mpidr_nodes[],
 		 * lower affinity levels.
 		 */
 		rc = psci_afflvl_suspend_handlers[level](node,
-							 entrypoint,
-							 context_id,
 							 power_state);
 		if (rc != PSCI_E_SUCCESS)
 			break;
@@ -306,8 +282,7 @@ static int psci_call_suspend_handlers(aff_map_node_t *mpidr_nodes[],
  * to turn off affinity level X it is neccesary to turn off affinity level X - 1
  * first.
  ******************************************************************************/
-int psci_afflvl_suspend(unsigned long entrypoint,
-			unsigned long context_id,
+int psci_afflvl_suspend(entry_point_info_t *ep,
 			unsigned int power_state,
 			int start_afflvl,
 			int end_afflvl)
@@ -356,12 +331,15 @@ int psci_afflvl_suspend(unsigned long entrypoint,
 	/* Stash the highest affinity level that will be turned off */
 	psci_set_max_phys_off_afflvl(max_phys_off_afflvl);
 
+	/*
+	 * Store the re-entry information for the non-secure world.
+	 */
+	cm_init_context(read_mpidr_el1(), ep);
+
 	/* Perform generic, architecture and platform specific handling */
 	rc = psci_call_suspend_handlers(mpidr_nodes,
 					start_afflvl,
 					end_afflvl,
-					entrypoint,
-					context_id,
 					power_state);
 
 	/*
diff --git a/services/std_svc/psci/psci_common.c b/services/std_svc/psci/psci_common.c
index 0a1cdf9e..507b56eb 100644
--- a/services/std_svc/psci/psci_common.c
+++ b/services/std_svc/psci/psci_common.c
@@ -290,15 +290,14 @@ int psci_validate_mpidr(unsigned long mpidr, int level)
 
 /*******************************************************************************
  * This function determines the full entrypoint information for the requested
- * PSCI entrypoint on power on/resume and saves this in the non-secure CPU
- * cpu_context, ready for when the core boots.
+ * PSCI entrypoint on power on/resume and returns it.
  ******************************************************************************/
-int psci_save_ns_entry(uint64_t mpidr,
-		       uint64_t entrypoint, uint64_t context_id,
-		       uint32_t ns_scr_el3, uint32_t ns_sctlr_el1)
+int psci_get_ns_ep_info(entry_point_info_t *ep,
+		       uint64_t entrypoint, uint64_t context_id)
 {
 	uint32_t ep_attr, mode, sctlr, daif, ee;
-	entry_point_info_t ep;
+	uint32_t ns_scr_el3 = read_scr_el3();
+	uint32_t ns_sctlr_el1 = read_sctlr_el1();
 
 	sctlr = ns_scr_el3 & SCR_HCE_BIT ? read_sctlr_el2() : ns_sctlr_el1;
 	ee = 0;
@@ -308,11 +307,11 @@ int psci_save_ns_entry(uint64_t mpidr,
 		ep_attr |= EP_EE_BIG;
 		ee = 1;
 	}
-	SET_PARAM_HEAD(&ep, PARAM_EP, VERSION_1, ep_attr);
+	SET_PARAM_HEAD(ep, PARAM_EP, VERSION_1, ep_attr);
 
-	ep.pc = entrypoint;
-	memset(&ep.args, 0, sizeof(ep.args));
-	ep.args.arg0 = context_id;
+	ep->pc = entrypoint;
+	memset(&ep->args, 0, sizeof(ep->args));
+	ep->args.arg0 = context_id;
 
 	/*
 	 * Figure out whether the cpu enters the non-secure address space
@@ -329,7 +328,7 @@ int psci_save_ns_entry(uint64_t mpidr,
 
 		mode = ns_scr_el3 & SCR_HCE_BIT ? MODE_EL2 : MODE_EL1;
 
-		ep.spsr = SPSR_64(mode, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
+		ep->spsr = SPSR_64(mode, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
 	} else {
 
 		mode = ns_scr_el3 & SCR_HCE_BIT ? MODE32_hyp : MODE32_svc;
@@ -340,12 +339,9 @@ int psci_save_ns_entry(uint64_t mpidr,
 		 */
 		daif = DAIF_ABT_BIT | DAIF_IRQ_BIT | DAIF_FIQ_BIT;
 
-		ep.spsr = SPSR_MODE32(mode, entrypoint & 0x1, ee, daif);
+		ep->spsr = SPSR_MODE32(mode, entrypoint & 0x1, ee, daif);
 	}
 
-	/* initialise an entrypoint to set up the CPU context */
-	cm_init_context(mpidr, &ep);
-
 	return PSCI_E_SUCCESS;
 }
 
diff --git a/services/std_svc/psci/psci_main.c b/services/std_svc/psci/psci_main.c
index 2e700e8a..7fce5faf 100644
--- a/services/std_svc/psci/psci_main.c
+++ b/services/std_svc/psci/psci_main.c
@@ -45,6 +45,7 @@ int psci_cpu_on(unsigned long target_cpu,
 {
 	int rc;
 	unsigned int start_afflvl, end_afflvl;
+	entry_point_info_t ep;
 
 	/* Determine if the cpu exists of not */
 	rc = psci_validate_mpidr(target_cpu, MPIDR_AFFLVL0);
@@ -53,14 +54,23 @@ int psci_cpu_on(unsigned long target_cpu,
 	}
 
 	/*
+	 * Verify and derive the re-entry information for
+	 * the non-secure world from the non-secure state from
+	 * where this call originated.
+	 */
+	rc = psci_get_ns_ep_info(&ep, entrypoint, context_id);
+	if (rc != PSCI_E_SUCCESS)
+		return rc;
+
+
+	/*
 	 * To turn this cpu on, specify which affinity
 	 * levels need to be turned on
 	 */
 	start_afflvl = MPIDR_AFFLVL0;
 	end_afflvl = get_max_afflvl();
 	rc = psci_afflvl_on(target_cpu,
-			    entrypoint,
-			    context_id,
+			    &ep,
 			    start_afflvl,
 			    end_afflvl);
 
@@ -79,6 +89,7 @@ int psci_cpu_suspend(unsigned int power_state,
 {
 	int rc;
 	unsigned int target_afflvl, pstate_type;
+	entry_point_info_t ep;
 
 	/* Check SBZ bits in power state are zero */
 	if (psci_validate_power_state(power_state))
@@ -106,12 +117,20 @@ int psci_cpu_suspend(unsigned int power_state,
 	}
 
 	/*
+	 * Verify and derive the re-entry information for
+	 * the non-secure world from the non-secure state from
+	 * where this call originated.
+	 */
+	rc = psci_get_ns_ep_info(&ep, entrypoint, context_id);
+	if (rc != PSCI_E_SUCCESS)
+		return rc;
+
+	/*
 	 * 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(entrypoint,
-				 context_id,
+	rc = psci_afflvl_suspend(&ep,
 				 power_state,
 				 MPIDR_AFFLVL0,
 				 target_afflvl);
diff --git a/services/std_svc/psci/psci_private.h b/services/std_svc/psci/psci_private.h
index 9a8ef73d..3a4ee3c8 100644
--- a/services/std_svc/psci/psci_private.h
+++ b/services/std_svc/psci/psci_private.h
@@ -33,6 +33,7 @@
 
 #include <arch.h>
 #include <bakery_lock.h>
+#include <bl_common.h>
 #include <psci.h>
 
 /*
@@ -101,9 +102,8 @@ int get_power_on_target_afflvl(void);
 void psci_afflvl_power_on_finish(int,
 				int,
 				afflvl_power_on_finisher_t *);
-int psci_save_ns_entry(uint64_t mpidr,
-		       uint64_t entrypoint, uint64_t context_id,
-		       uint32_t caller_scr_el3, uint32_t caller_sctlr_el1);
+int psci_get_ns_ep_info(entry_point_info_t *ep,
+		       uint64_t entrypoint, uint64_t context_id);
 int psci_check_afflvl_range(int start_afflvl, int end_afflvl);
 void psci_do_afflvl_state_mgmt(uint32_t start_afflvl,
 			       uint32_t end_afflvl,
@@ -129,21 +129,20 @@ int psci_get_aff_map_nodes(unsigned long mpidr,
 aff_map_node_t *psci_get_aff_map_node(unsigned long, int);
 
 /* Private exported functions from psci_affinity_on.c */
-int psci_afflvl_on(unsigned long,
-			unsigned long,
-			unsigned long,
-			int,
-			int);
+int psci_afflvl_on(unsigned long target_cpu,
+		   entry_point_info_t *ep,
+		   int start_afflvl,
+		   int end_afflvl);
 
 /* Private exported functions from psci_affinity_off.c */
 int psci_afflvl_off(int, int);
 
 /* Private exported functions from psci_affinity_suspend.c */
-int psci_afflvl_suspend(unsigned long,
-			unsigned long,
-			unsigned int,
-			int,
-			int);
+int psci_afflvl_suspend(entry_point_info_t *ep,
+			unsigned int power_state,
+			int start_afflvl,
+			int end_afflvl);
+
 unsigned int psci_afflvl_suspend_finish(int, int);
 void psci_set_suspend_power_state(unsigned int power_state);