services/std_svc/psci/psci_main.c - filogic/atf - Gitiles

 /*
  * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * Redistributions of source code must retain the above copyright notice, this
  * list of conditions and the following disclaimer.
  *
  * Redistributions in binary form must reproduce the above copyright notice,
  * this list of conditions and the following disclaimer in the documentation
  * and/or other materials provided with the distribution.
  *
  * Neither the name of ARM nor the names of its contributors may be used
  * to endorse or promote products derived from this software without specific
  * prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  */

 #include <arch.h>
 #include <arch_helpers.h>
 #include <assert.h>
 #include <debug.h>
 #include <platform.h>
 #include <runtime_svc.h>
 #include <std_svc.h>
 #include "psci_private.h"

 /*******************************************************************************
  * PSCI frontend api for servicing SMCs. Described in the PSCI spec.
  ******************************************************************************/
 int psci_cpu_on(unsigned long target_cpu,
 		unsigned long entrypoint,
 		unsigned long context_id)

 {
 	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);
 	if (rc != PSCI_E_SUCCESS) {
 		return PSCI_E_INVALID_PARAMS;
 	}

 	/* Validate the entrypoint using platform pm_ops */
 	if (psci_plat_pm_ops->validate_ns_entrypoint) {
 		rc = psci_plat_pm_ops->validate_ns_entrypoint(entrypoint);
 		if (rc != PSCI_E_SUCCESS) {
 			assert(rc == PSCI_E_INVALID_PARAMS);
 			return PSCI_E_INVALID_PARAMS;
 		}
 	}

 	/*
 	 * 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 = PLATFORM_MAX_AFFLVL;
 	rc = psci_afflvl_on(target_cpu,
 			    &ep,
 			    start_afflvl,
 			    end_afflvl);

 	return rc;
 }

 unsigned int psci_version(void)
 {
 	return PSCI_MAJOR_VER | PSCI_MINOR_VER;
 }

 int psci_cpu_suspend(unsigned int power_state,
 		     unsigned long entrypoint,
 		     unsigned long context_id)
 {
 	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))
 		return PSCI_E_INVALID_PARAMS;

 	/* Sanity check the requested state */
 	target_afflvl = psci_get_pstate_afflvl(power_state);
 	if (target_afflvl > PLATFORM_MAX_AFFLVL)
 		return PSCI_E_INVALID_PARAMS;

 	/* Validate the power_state using platform pm_ops */
 	if (psci_plat_pm_ops->validate_power_state) {
 		rc = psci_plat_pm_ops->validate_power_state(power_state);
 		if (rc != PSCI_E_SUCCESS) {
 			assert(rc == PSCI_E_INVALID_PARAMS);
 			return PSCI_E_INVALID_PARAMS;
 		}
 	}

 	/* Validate the entrypoint using platform pm_ops */
 	if (psci_plat_pm_ops->validate_ns_entrypoint) {
 		rc = psci_plat_pm_ops->validate_ns_entrypoint(entrypoint);
 		if (rc != PSCI_E_SUCCESS) {
 			assert(rc == PSCI_E_INVALID_PARAMS);
 			return PSCI_E_INVALID_PARAMS;
 		}
 	}

 	/* Determine the 'state type' in the 'power_state' parameter */
 	pstate_type = psci_get_pstate_type(power_state);

 	/*
 	 * Ensure that we have a platform specific handler for entering
 	 * a standby state.
 	 */
 	if (pstate_type == PSTATE_TYPE_STANDBY) {
 		if  (!psci_plat_pm_ops->affinst_standby)
 			return PSCI_E_INVALID_PARAMS;

 		psci_plat_pm_ops->affinst_standby(power_state);
 		return PSCI_E_SUCCESS;
 	}

 	/*
 	 * 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;

 	/* 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.
 	 */
 	psci_afflvl_suspend(&ep,
 			    MPIDR_AFFLVL0,
 			    target_afflvl);

 	/* Reset PSCI power state parameter for the core. */
 	psci_set_suspend_power_state(PSCI_INVALID_DATA);
 	return PSCI_E_SUCCESS;
 }

 int psci_system_suspend(unsigned long entrypoint,
 			unsigned long context_id)
 {
 	int rc;
 	unsigned int power_state;
 	entry_point_info_t ep;

 	/* Validate the entrypoint using platform pm_ops */
 	if (psci_plat_pm_ops->validate_ns_entrypoint) {
 		rc = psci_plat_pm_ops->validate_ns_entrypoint(entrypoint);
 		if (rc != PSCI_E_SUCCESS) {
 			assert(rc == PSCI_E_INVALID_PARAMS);
 			return PSCI_E_INVALID_PARAMS;
 		}
 	}

 	/* Check if the current CPU is the last ON CPU in the system */
 	if (!psci_is_last_on_cpu())
 		return PSCI_E_DENIED;

 	/*
 	 * 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;

 	/*
 	 * Assert that the required pm_ops hook is implemented to ensure that
 	 * the capability detected during psci_setup() is valid.
 	 */
 	assert(psci_plat_pm_ops->get_sys_suspend_power_state);

 	/*
 	 * Query the platform for the power_state required for system suspend
 	 */
 	power_state = psci_plat_pm_ops->get_sys_suspend_power_state();

 	/* 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.
 	 */
 	psci_afflvl_suspend(&ep,
 			    MPIDR_AFFLVL0,
 			    PLATFORM_MAX_AFFLVL);

 	/* Reset PSCI power state parameter for the core. */
 	psci_set_suspend_power_state(PSCI_INVALID_DATA);
 	return PSCI_E_SUCCESS;
 }

 int psci_cpu_off(void)
 {
 	int rc;
 	int target_afflvl = PLATFORM_MAX_AFFLVL;

 	/*
 	 * Traverse from the highest to the lowest affinity level. When the
 	 * lowest affinity level is hit, all the locks are acquired. State
 	 * management is done immediately followed by cpu, cluster ...
 	 * ..target_afflvl specific actions as this function unwinds back.
 	 */
 	rc = psci_afflvl_off(MPIDR_AFFLVL0, target_afflvl);

 	/*
 	 * The only error cpu_off can return is E_DENIED. So check if that's
 	 * indeed the case.
 	 */
 	assert (rc == PSCI_E_DENIED);

 	return rc;
 }

 int psci_affinity_info(unsigned long target_affinity,
 		       unsigned int lowest_affinity_level)
 {
 	int rc = PSCI_E_INVALID_PARAMS;
 	unsigned int aff_state;
 	aff_map_node_t *node;

 	if (lowest_affinity_level > PLATFORM_MAX_AFFLVL)
 		return rc;

 	node = psci_get_aff_map_node(target_affinity, lowest_affinity_level);
 	if (node && (node->state & PSCI_AFF_PRESENT)) {

 		/*
 		 * TODO: For affinity levels higher than 0 i.e. cpu, the
 		 * state will always be either ON or OFF. Need to investigate
 		 * how critical is it to support ON_PENDING here.
 		 */
 		aff_state = psci_get_state(node);

 		/* A suspended cpu is available & on for the OS */
 		if (aff_state == PSCI_STATE_SUSPEND) {
 			aff_state = PSCI_STATE_ON;
 		}

 		rc = aff_state;
 	}

 	return rc;
 }

 int psci_migrate(unsigned long target_cpu)
 {
 	int rc;
 	unsigned long resident_cpu_mpidr;

 	rc = psci_spd_migrate_info(&resident_cpu_mpidr);
 	if (rc != PSCI_TOS_UP_MIG_CAP)
 		return (rc == PSCI_TOS_NOT_UP_MIG_CAP) ?
 			  PSCI_E_DENIED : PSCI_E_NOT_SUPPORTED;

 	/*
 	 * Migrate should only be invoked on the CPU where
 	 * the Secure OS is resident.
 	 */
 	if (resident_cpu_mpidr != read_mpidr_el1())
 		return PSCI_E_NOT_PRESENT;

 	/* Check the validity of the specified target cpu */
 	rc = psci_validate_mpidr(target_cpu, MPIDR_AFFLVL0);
 	if (rc != PSCI_E_SUCCESS)
 		return PSCI_E_INVALID_PARAMS;

 	assert(psci_spd_pm && psci_spd_pm->svc_migrate);

 	rc = psci_spd_pm->svc_migrate(read_mpidr_el1(), target_cpu);
 	assert(rc == PSCI_E_SUCCESS || rc == PSCI_E_INTERN_FAIL);

 	return rc;
 }

 int psci_migrate_info_type(void)
 {
 	unsigned long resident_cpu_mpidr;

 	return psci_spd_migrate_info(&resident_cpu_mpidr);
 }

 long psci_migrate_info_up_cpu(void)
 {
 	unsigned long resident_cpu_mpidr;
 	int rc;

 	/*
 	 * Return value of this depends upon what
 	 * psci_spd_migrate_info() returns.
 	 */
 	rc = psci_spd_migrate_info(&resident_cpu_mpidr);
 	if (rc != PSCI_TOS_NOT_UP_MIG_CAP && rc != PSCI_TOS_UP_MIG_CAP)
 		return PSCI_E_INVALID_PARAMS;

 	return resident_cpu_mpidr;
 }

 int psci_features(unsigned int psci_fid)
 {
 	uint32_t local_caps = psci_caps;

 	/* Check if it is a 64 bit function */
 	if (((psci_fid >> FUNCID_CC_SHIFT) & FUNCID_CC_MASK) == SMC_64)
 		local_caps &= PSCI_CAP_64BIT_MASK;

 	/* Check for invalid fid */
 	if (!(is_std_svc_call(psci_fid) && is_valid_fast_smc(psci_fid)
 			&& is_psci_fid(psci_fid)))
 		return PSCI_E_NOT_SUPPORTED;


 	/* Check if the psci fid is supported or not */
 	if (!(local_caps & define_psci_cap(psci_fid)))
 		return PSCI_E_NOT_SUPPORTED;

 	/* Format the feature flags */
 	if (psci_fid == PSCI_CPU_SUSPEND_AARCH32 ||
 			psci_fid == PSCI_CPU_SUSPEND_AARCH64) {
 		/*
 		 * The trusted firmware uses the original power state format
 		 * and does not support OS Initiated Mode.
 		 */
 		return (FF_PSTATE_ORIG << FF_PSTATE_SHIFT) |
 			((!FF_SUPPORTS_OS_INIT_MODE) << FF_MODE_SUPPORT_SHIFT);
 	}

 	/* Return 0 for all other fid's */
 	return PSCI_E_SUCCESS;
 }

 /*******************************************************************************
  * PSCI top level handler for servicing SMCs.
  ******************************************************************************/
 uint64_t psci_smc_handler(uint32_t smc_fid,
 			  uint64_t x1,
 			  uint64_t x2,
 			  uint64_t x3,
 			  uint64_t x4,
 			  void *cookie,
 			  void *handle,
 			  uint64_t flags)
 {
 	if (is_caller_secure(flags))
 		SMC_RET1(handle, SMC_UNK);

 	/* Check the fid against the capabilities */
 	if (!(psci_caps & define_psci_cap(smc_fid)))
 		SMC_RET1(handle, SMC_UNK);

 	if (((smc_fid >> FUNCID_CC_SHIFT) & FUNCID_CC_MASK) == SMC_32) {
 		/* 32-bit PSCI function, clear top parameter bits */

 		x1 = (uint32_t)x1;
 		x2 = (uint32_t)x2;
 		x3 = (uint32_t)x3;

 		switch (smc_fid) {
 		case PSCI_VERSION:
 			SMC_RET1(handle, psci_version());

 		case PSCI_CPU_OFF:
 			SMC_RET1(handle, psci_cpu_off());

 		case PSCI_CPU_SUSPEND_AARCH32:
 			SMC_RET1(handle, psci_cpu_suspend(x1, x2, x3));

 		case PSCI_CPU_ON_AARCH32:
 			SMC_RET1(handle, psci_cpu_on(x1, x2, x3));

 		case PSCI_AFFINITY_INFO_AARCH32:
 			SMC_RET1(handle, psci_affinity_info(x1, x2));

 		case PSCI_MIG_AARCH32:
 			SMC_RET1(handle, psci_migrate(x1));

 		case PSCI_MIG_INFO_TYPE:
 			SMC_RET1(handle, psci_migrate_info_type());

 		case PSCI_MIG_INFO_UP_CPU_AARCH32:
 			SMC_RET1(handle, psci_migrate_info_up_cpu());

 		case PSCI_SYSTEM_SUSPEND_AARCH32:
 			SMC_RET1(handle, psci_system_suspend(x1, x2));

 		case PSCI_SYSTEM_OFF:
 			psci_system_off();
 			/* We should never return from psci_system_off() */

 		case PSCI_SYSTEM_RESET:
 			psci_system_reset();
 			/* We should never return from psci_system_reset() */

 		case PSCI_FEATURES:
 			SMC_RET1(handle, psci_features(x1));

 		default:
 			break;
 		}
 	} else {
 		/* 64-bit PSCI function */

 		switch (smc_fid) {
 		case PSCI_CPU_SUSPEND_AARCH64:
 			SMC_RET1(handle, psci_cpu_suspend(x1, x2, x3));

 		case PSCI_CPU_ON_AARCH64:
 			SMC_RET1(handle, psci_cpu_on(x1, x2, x3));

 		case PSCI_AFFINITY_INFO_AARCH64:
 			SMC_RET1(handle, psci_affinity_info(x1, x2));

 		case PSCI_MIG_AARCH64:
 			SMC_RET1(handle, psci_migrate(x1));

 		case PSCI_MIG_INFO_UP_CPU_AARCH64:
 			SMC_RET1(handle, psci_migrate_info_up_cpu());

 		case PSCI_SYSTEM_SUSPEND_AARCH64:
 			SMC_RET1(handle, psci_system_suspend(x1, x2));

 		default:
 			break;
 		}
 	}

 	WARN("Unimplemented PSCI Call: 0x%x \n", smc_fid);
 	SMC_RET1(handle, SMC_UNK);
 }
	/*
	* Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	*
	* Redistributions of source code must retain the above copyright notice, this
	* list of conditions and the following disclaimer.
	*
	* Redistributions in binary form must reproduce the above copyright notice,
	* this list of conditions and the following disclaimer in the documentation
	* and/or other materials provided with the distribution.
	*
	* Neither the name of ARM nor the names of its contributors may be used
	* to endorse or promote products derived from this software without specific
	* prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	* POSSIBILITY OF SUCH DAMAGE.
	*/

	#include <arch.h>
	#include <arch_helpers.h>
	#include <assert.h>
	#include <debug.h>
	#include <platform.h>
	#include <runtime_svc.h>
	#include <std_svc.h>
	#include "psci_private.h"

	/*******************************************************************************
	* PSCI frontend api for servicing SMCs. Described in the PSCI spec.
	******************************************************************************/
	int psci_cpu_on(unsigned long target_cpu,
	unsigned long entrypoint,
	unsigned long context_id)

	{
	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);
	if (rc != PSCI_E_SUCCESS) {
	return PSCI_E_INVALID_PARAMS;
	}

	/* Validate the entrypoint using platform pm_ops */
	if (psci_plat_pm_ops->validate_ns_entrypoint) {
	rc = psci_plat_pm_ops->validate_ns_entrypoint(entrypoint);
	if (rc != PSCI_E_SUCCESS) {
	assert(rc == PSCI_E_INVALID_PARAMS);
	return PSCI_E_INVALID_PARAMS;
	}
	}

	/*
	* 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 = PLATFORM_MAX_AFFLVL;
	rc = psci_afflvl_on(target_cpu,
	&ep,
	start_afflvl,
	end_afflvl);

	return rc;
	}

	unsigned int psci_version(void)
	{
	return PSCI_MAJOR_VER \| PSCI_MINOR_VER;
	}

	int psci_cpu_suspend(unsigned int power_state,
	unsigned long entrypoint,
	unsigned long context_id)
	{
	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))
	return PSCI_E_INVALID_PARAMS;

	/* Sanity check the requested state */
	target_afflvl = psci_get_pstate_afflvl(power_state);
	if (target_afflvl > PLATFORM_MAX_AFFLVL)
	return PSCI_E_INVALID_PARAMS;

	/* Validate the power_state using platform pm_ops */
	if (psci_plat_pm_ops->validate_power_state) {
	rc = psci_plat_pm_ops->validate_power_state(power_state);
	if (rc != PSCI_E_SUCCESS) {
	assert(rc == PSCI_E_INVALID_PARAMS);
	return PSCI_E_INVALID_PARAMS;
	}
	}

	/* Validate the entrypoint using platform pm_ops */
	if (psci_plat_pm_ops->validate_ns_entrypoint) {
	rc = psci_plat_pm_ops->validate_ns_entrypoint(entrypoint);
	if (rc != PSCI_E_SUCCESS) {
	assert(rc == PSCI_E_INVALID_PARAMS);
	return PSCI_E_INVALID_PARAMS;
	}
	}

	/* Determine the 'state type' in the 'power_state' parameter */
	pstate_type = psci_get_pstate_type(power_state);

	/*
	* Ensure that we have a platform specific handler for entering
	* a standby state.
	*/
	if (pstate_type == PSTATE_TYPE_STANDBY) {
	if (!psci_plat_pm_ops->affinst_standby)
	return PSCI_E_INVALID_PARAMS;

	psci_plat_pm_ops->affinst_standby(power_state);
	return PSCI_E_SUCCESS;
	}

	/*
	* 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;

	/* 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.
	*/
	psci_afflvl_suspend(&ep,
	MPIDR_AFFLVL0,
	target_afflvl);

	/* Reset PSCI power state parameter for the core. */
	psci_set_suspend_power_state(PSCI_INVALID_DATA);
	return PSCI_E_SUCCESS;
	}

	int psci_system_suspend(unsigned long entrypoint,
	unsigned long context_id)
	{
	int rc;
	unsigned int power_state;
	entry_point_info_t ep;

	/* Validate the entrypoint using platform pm_ops */
	if (psci_plat_pm_ops->validate_ns_entrypoint) {
	rc = psci_plat_pm_ops->validate_ns_entrypoint(entrypoint);
	if (rc != PSCI_E_SUCCESS) {
	assert(rc == PSCI_E_INVALID_PARAMS);
	return PSCI_E_INVALID_PARAMS;
	}
	}

	/* Check if the current CPU is the last ON CPU in the system */
	if (!psci_is_last_on_cpu())
	return PSCI_E_DENIED;

	/*
	* 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;

	/*
	* Assert that the required pm_ops hook is implemented to ensure that
	* the capability detected during psci_setup() is valid.
	*/
	assert(psci_plat_pm_ops->get_sys_suspend_power_state);

	/*
	* Query the platform for the power_state required for system suspend
	*/
	power_state = psci_plat_pm_ops->get_sys_suspend_power_state();

	/* 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.
	*/
	psci_afflvl_suspend(&ep,
	MPIDR_AFFLVL0,
	PLATFORM_MAX_AFFLVL);

	/* Reset PSCI power state parameter for the core. */
	psci_set_suspend_power_state(PSCI_INVALID_DATA);
	return PSCI_E_SUCCESS;
	}

	int psci_cpu_off(void)
	{
	int rc;
	int target_afflvl = PLATFORM_MAX_AFFLVL;

	/*
	* Traverse from the highest to the lowest affinity level. When the
	* lowest affinity level is hit, all the locks are acquired. State
	* management is done immediately followed by cpu, cluster ...
	* ..target_afflvl specific actions as this function unwinds back.
	*/
	rc = psci_afflvl_off(MPIDR_AFFLVL0, target_afflvl);

	/*
	* The only error cpu_off can return is E_DENIED. So check if that's
	* indeed the case.
	*/
	assert (rc == PSCI_E_DENIED);

	return rc;
	}

	int psci_affinity_info(unsigned long target_affinity,
	unsigned int lowest_affinity_level)
	{
	int rc = PSCI_E_INVALID_PARAMS;
	unsigned int aff_state;
	aff_map_node_t *node;

	if (lowest_affinity_level > PLATFORM_MAX_AFFLVL)
	return rc;

	node = psci_get_aff_map_node(target_affinity, lowest_affinity_level);
	if (node && (node->state & PSCI_AFF_PRESENT)) {

	/*
	* TODO: For affinity levels higher than 0 i.e. cpu, the
	* state will always be either ON or OFF. Need to investigate
	* how critical is it to support ON_PENDING here.
	*/
	aff_state = psci_get_state(node);

	/* A suspended cpu is available & on for the OS */
	if (aff_state == PSCI_STATE_SUSPEND) {
	aff_state = PSCI_STATE_ON;
	}

	rc = aff_state;
	}

	return rc;
	}

	int psci_migrate(unsigned long target_cpu)
	{
	int rc;
	unsigned long resident_cpu_mpidr;

	rc = psci_spd_migrate_info(&resident_cpu_mpidr);
	if (rc != PSCI_TOS_UP_MIG_CAP)
	return (rc == PSCI_TOS_NOT_UP_MIG_CAP) ?
	PSCI_E_DENIED : PSCI_E_NOT_SUPPORTED;

	/*
	* Migrate should only be invoked on the CPU where
	* the Secure OS is resident.
	*/
	if (resident_cpu_mpidr != read_mpidr_el1())
	return PSCI_E_NOT_PRESENT;

	/* Check the validity of the specified target cpu */
	rc = psci_validate_mpidr(target_cpu, MPIDR_AFFLVL0);
	if (rc != PSCI_E_SUCCESS)
	return PSCI_E_INVALID_PARAMS;

	assert(psci_spd_pm && psci_spd_pm->svc_migrate);

	rc = psci_spd_pm->svc_migrate(read_mpidr_el1(), target_cpu);
	assert(rc == PSCI_E_SUCCESS \|\| rc == PSCI_E_INTERN_FAIL);

	return rc;
	}

	int psci_migrate_info_type(void)
	{
	unsigned long resident_cpu_mpidr;

	return psci_spd_migrate_info(&resident_cpu_mpidr);
	}

	long psci_migrate_info_up_cpu(void)
	{
	unsigned long resident_cpu_mpidr;
	int rc;

	/*
	* Return value of this depends upon what
	* psci_spd_migrate_info() returns.
	*/
	rc = psci_spd_migrate_info(&resident_cpu_mpidr);
	if (rc != PSCI_TOS_NOT_UP_MIG_CAP && rc != PSCI_TOS_UP_MIG_CAP)
	return PSCI_E_INVALID_PARAMS;

	return resident_cpu_mpidr;
	}

	int psci_features(unsigned int psci_fid)
	{
	uint32_t local_caps = psci_caps;

	/* Check if it is a 64 bit function */
	if (((psci_fid >> FUNCID_CC_SHIFT) & FUNCID_CC_MASK) == SMC_64)
	local_caps &= PSCI_CAP_64BIT_MASK;

	/* Check for invalid fid */
	if (!(is_std_svc_call(psci_fid) && is_valid_fast_smc(psci_fid)
	&& is_psci_fid(psci_fid)))
	return PSCI_E_NOT_SUPPORTED;


	/* Check if the psci fid is supported or not */
	if (!(local_caps & define_psci_cap(psci_fid)))
	return PSCI_E_NOT_SUPPORTED;

	/* Format the feature flags */
	if (psci_fid == PSCI_CPU_SUSPEND_AARCH32 \|\|
	psci_fid == PSCI_CPU_SUSPEND_AARCH64) {
	/*
	* The trusted firmware uses the original power state format
	* and does not support OS Initiated Mode.
	*/
	return (FF_PSTATE_ORIG << FF_PSTATE_SHIFT) \|
	((!FF_SUPPORTS_OS_INIT_MODE) << FF_MODE_SUPPORT_SHIFT);
	}

	/* Return 0 for all other fid's */
	return PSCI_E_SUCCESS;
	}

	/*******************************************************************************
	* PSCI top level handler for servicing SMCs.
	******************************************************************************/
	uint64_t psci_smc_handler(uint32_t smc_fid,
	uint64_t x1,
	uint64_t x2,
	uint64_t x3,
	uint64_t x4,
	void *cookie,
	void *handle,
	uint64_t flags)
	{
	if (is_caller_secure(flags))
	SMC_RET1(handle, SMC_UNK);

	/* Check the fid against the capabilities */
	if (!(psci_caps & define_psci_cap(smc_fid)))
	SMC_RET1(handle, SMC_UNK);

	if (((smc_fid >> FUNCID_CC_SHIFT) & FUNCID_CC_MASK) == SMC_32) {
	/* 32-bit PSCI function, clear top parameter bits */

	x1 = (uint32_t)x1;
	x2 = (uint32_t)x2;
	x3 = (uint32_t)x3;

	switch (smc_fid) {
	case PSCI_VERSION:
	SMC_RET1(handle, psci_version());

	case PSCI_CPU_OFF:
	SMC_RET1(handle, psci_cpu_off());

	case PSCI_CPU_SUSPEND_AARCH32:
	SMC_RET1(handle, psci_cpu_suspend(x1, x2, x3));

	case PSCI_CPU_ON_AARCH32:
	SMC_RET1(handle, psci_cpu_on(x1, x2, x3));

	case PSCI_AFFINITY_INFO_AARCH32:
	SMC_RET1(handle, psci_affinity_info(x1, x2));

	case PSCI_MIG_AARCH32:
	SMC_RET1(handle, psci_migrate(x1));

	case PSCI_MIG_INFO_TYPE:
	SMC_RET1(handle, psci_migrate_info_type());

	case PSCI_MIG_INFO_UP_CPU_AARCH32:
	SMC_RET1(handle, psci_migrate_info_up_cpu());

	case PSCI_SYSTEM_SUSPEND_AARCH32:
	SMC_RET1(handle, psci_system_suspend(x1, x2));

	case PSCI_SYSTEM_OFF:
	psci_system_off();
	/* We should never return from psci_system_off() */

	case PSCI_SYSTEM_RESET:
	psci_system_reset();
	/* We should never return from psci_system_reset() */

	case PSCI_FEATURES:
	SMC_RET1(handle, psci_features(x1));

	default:
	break;
	}
	} else {
	/* 64-bit PSCI function */

	switch (smc_fid) {
	case PSCI_CPU_SUSPEND_AARCH64:
	SMC_RET1(handle, psci_cpu_suspend(x1, x2, x3));

	case PSCI_CPU_ON_AARCH64:
	SMC_RET1(handle, psci_cpu_on(x1, x2, x3));

	case PSCI_AFFINITY_INFO_AARCH64:
	SMC_RET1(handle, psci_affinity_info(x1, x2));

	case PSCI_MIG_AARCH64:
	SMC_RET1(handle, psci_migrate(x1));

	case PSCI_MIG_INFO_UP_CPU_AARCH64:
	SMC_RET1(handle, psci_migrate_info_up_cpu());

	case PSCI_SYSTEM_SUSPEND_AARCH64:
	SMC_RET1(handle, psci_system_suspend(x1, x2));

	default:
	break;
	}
	}

	WARN("Unimplemented PSCI Call: 0x%x \n", smc_fid);
	SMC_RET1(handle, SMC_UNK);
	}