services/std_svc/spm/spm_main.c - filogic/atf - Gitiles

 /*
  * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */

 #include <arch_helpers.h>
 #include <assert.h>
 #include <bl31.h>
 #include <context_mgmt.h>
 #include <debug.h>
 #include <errno.h>
 #include <platform.h>
 #include <runtime_svc.h>
 #include <secure_partition.h>
 #include <smcc.h>
 #include <smcc_helpers.h>
 #include <spinlock.h>
 #include <spm_svc.h>
 #include <utils.h>
 #include <xlat_tables_v2.h>

 #include "spm_private.h"

 /* Lock used for SP_MEMORY_ATTRIBUTES_GET and SP_MEMORY_ATTRIBUTES_SET */
 static spinlock_t mem_attr_smc_lock;

 /*******************************************************************************
  * Secure Partition context information.
  ******************************************************************************/
 static secure_partition_context_t sp_ctx;
 unsigned int sp_init_in_progress;

 /*******************************************************************************
  * Replace the S-EL1 re-entry information with S-EL0 re-entry
  * information
  ******************************************************************************/
 void spm_setup_next_eret_into_sel0(cpu_context_t *secure_context)
 {
 	assert(secure_context == cm_get_context(SECURE));

 	cm_set_elr_spsr_el3(SECURE, read_elr_el1(), read_spsr_el1());
 }

 /*******************************************************************************
  * This function takes an SP context pointer and:
  * 1. Applies the S-EL1 system register context from sp_ctx->cpu_ctx.
  * 2. Saves the current C runtime state (callee-saved registers) on the stack
  *    frame and saves a reference to this state.
  * 3. Calls el3_exit() so that the EL3 system and general purpose registers
  *    from the sp_ctx->cpu_ctx are used to enter the secure partition image.
  ******************************************************************************/
 static uint64_t spm_synchronous_sp_entry(secure_partition_context_t *sp_ctx_ptr)
 {
 	uint64_t rc;

 	assert(sp_ctx_ptr != NULL);
 	assert(sp_ctx_ptr->c_rt_ctx == 0);
 	assert(cm_get_context(SECURE) == &sp_ctx_ptr->cpu_ctx);

 	/* Apply the Secure EL1 system register context and switch to it */
 	cm_el1_sysregs_context_restore(SECURE);
 	cm_set_next_eret_context(SECURE);

 	VERBOSE("%s: We're about to enter the Secure partition...\n", __func__);

 	rc = spm_secure_partition_enter(&sp_ctx_ptr->c_rt_ctx);
 #if ENABLE_ASSERTIONS
 	sp_ctx_ptr->c_rt_ctx = 0;
 #endif

 	return rc;
 }


 /*******************************************************************************
  * This function takes a Secure partition context pointer and:
  * 1. Saves the S-EL1 system register context to sp_ctx->cpu_ctx.
  * 2. Restores the current C runtime state (callee saved registers) from the
  *    stack frame using the reference to this state saved in
  *    spm_secure_partition_enter().
  * 3. It does not need to save any general purpose or EL3 system register state
  *    as the generic smc entry routine should have saved those.
  ******************************************************************************/
 static void __dead2 spm_synchronous_sp_exit(
 			secure_partition_context_t *sp_ctx_ptr, uint64_t ret)
 {
 	assert(sp_ctx_ptr != NULL);
 	/* Save the Secure EL1 system register context */
 	assert(cm_get_context(SECURE) == &sp_ctx_ptr->cpu_ctx);
 	cm_el1_sysregs_context_save(SECURE);

 	assert(sp_ctx_ptr->c_rt_ctx != 0);
 	spm_secure_partition_exit(sp_ctx_ptr->c_rt_ctx, ret);

 	/* Should never reach here */
 	assert(0);
 }

 /*******************************************************************************
  * This function passes control to the Secure Partition image (BL32) for the
  * first time on the primary cpu after a cold boot. It assumes that a valid
  * secure context has already been created by spm_setup() which can be directly
  * used. This function performs a synchronous entry into the Secure partition.
  * The SP passes control back to this routine through a SMC.
  ******************************************************************************/
 int32_t spm_init(void)
 {
 	entry_point_info_t *secure_partition_ep_info;
 	uint64_t rc;

 	VERBOSE("%s entry\n", __func__);

 	/*
 	 * Get information about the Secure Partition (BL32) image. Its
 	 * absence is a critical failure.
 	 */
 	secure_partition_ep_info = bl31_plat_get_next_image_ep_info(SECURE);
 	assert(secure_partition_ep_info);

 	/*
 	 * Initialise the common context and then overlay the S-EL0 specific
 	 * context on top of it.
 	 */
 	cm_init_my_context(secure_partition_ep_info);
 	secure_partition_setup();

 	/*
 	 * Arrange for an entry into the secure partition.
 	 */
 	sp_init_in_progress = 1;
 	rc = spm_synchronous_sp_entry(&sp_ctx);
 	assert(rc == 0);
 	sp_init_in_progress = 0;
 	VERBOSE("SP_MEMORY_ATTRIBUTES_SET_AARCH64 availability has been revoked\n");

 	return rc;
 }

 /*******************************************************************************
  * Given a secure partition entrypoint info pointer, entry point PC & pointer to
  * a context data structure, this function will initialize the SPM context and
  * entry point info for the secure partition.
  ******************************************************************************/
 void spm_init_sp_ep_state(struct entry_point_info *sp_ep_info,
 			  uint64_t pc,
 			  secure_partition_context_t *sp_ctx_ptr)
 {
 	uint32_t ep_attr;

 	assert(sp_ep_info);
 	assert(pc);
 	assert(sp_ctx_ptr);

 	cm_set_context(&sp_ctx_ptr->cpu_ctx, SECURE);

 	/* initialise an entrypoint to set up the CPU context */
 	ep_attr = SECURE | EP_ST_ENABLE;
 	if (read_sctlr_el3() & SCTLR_EE_BIT)
 		ep_attr |= EP_EE_BIG;
 	SET_PARAM_HEAD(sp_ep_info, PARAM_EP, VERSION_1, ep_attr);

 	sp_ep_info->pc = pc;
 	/* The secure partition runs in S-EL0. */
 	sp_ep_info->spsr = SPSR_64(MODE_EL0,
 				   MODE_SP_EL0,
 				   DISABLE_ALL_EXCEPTIONS);

 	zeromem(&sp_ep_info->args, sizeof(sp_ep_info->args));
 }

 /*******************************************************************************
  * Secure Partition Manager setup. The SPM finds out the SP entrypoint if not
  * already known and initialises the context for entry into the SP for its
  * initialisation.
  ******************************************************************************/
 int32_t spm_setup(void)
 {
 	entry_point_info_t *secure_partition_ep_info;

 	VERBOSE("%s entry\n", __func__);

 	/*
 	 * Get information about the Secure Partition (BL32) image. Its
 	 * absence is a critical failure.
 	 */
 	secure_partition_ep_info = bl31_plat_get_next_image_ep_info(SECURE);
 	if (!secure_partition_ep_info) {
 		WARN("No SPM provided by BL2 boot loader, Booting device"
 			" without SPM initialization. SMCs destined for SPM"
 			" will return SMC_UNK\n");
 		return 1;
 	}

 	/*
 	 * If there's no valid entry point for SP, we return a non-zero value
 	 * signalling failure initializing the service. We bail out without
 	 * registering any handlers
 	 */
 	if (!secure_partition_ep_info->pc) {
 		return 1;
 	}

 	spm_init_sp_ep_state(secure_partition_ep_info,
 			      secure_partition_ep_info->pc,
 			      &sp_ctx);

 	/*
 	 * All SPM initialization done. Now register our init function with
 	 * BL31 for deferred invocation
 	 */
 	bl31_register_bl32_init(&spm_init);

 	VERBOSE("%s exit\n", __func__);

 	return 0;
 }

 /*
  * Attributes are encoded using a different format in the SMC interface than in
  * the Trusted Firmware, where the mmap_attr_t enum type is used. This function
  * converts an attributes value from the SMC format to the mmap_attr_t format by
  * setting MT_RW/MT_RO, MT_USER/MT_PRIVILEGED and MT_EXECUTE/MT_EXECUTE_NEVER.
  * The other fields are left as 0 because they are ignored by the function
  * change_mem_attributes().
  */
 static mmap_attr_t smc_attr_to_mmap_attr(unsigned int attributes)
 {
 	mmap_attr_t tf_attr = 0;

 	unsigned int access = (attributes & SP_MEMORY_ATTRIBUTES_ACCESS_MASK)
 			      >> SP_MEMORY_ATTRIBUTES_ACCESS_SHIFT;

 	if (access == SP_MEMORY_ATTRIBUTES_ACCESS_RW) {
 		tf_attr |= MT_RW | MT_USER;
 	} else if (access ==  SP_MEMORY_ATTRIBUTES_ACCESS_RO) {
 		tf_attr |= MT_RO | MT_USER;
 	} else {
 		/* Other values are reserved. */
 		assert(access ==  SP_MEMORY_ATTRIBUTES_ACCESS_NOACCESS);
 		/* The only requirement is that there's no access from EL0 */
 		tf_attr |= MT_RO | MT_PRIVILEGED;
 	}

 	if ((attributes & SP_MEMORY_ATTRIBUTES_NON_EXEC) == 0) {
 		tf_attr |= MT_EXECUTE;
 	} else {
 		tf_attr |= MT_EXECUTE_NEVER;
 	}

 	return tf_attr;
 }

 /*
  * This function converts attributes from the Trusted Firmware format into the
  * SMC interface format.
  */
 static int smc_mmap_to_smc_attr(mmap_attr_t attr)
 {
 	int smc_attr = 0;

 	int data_access;

 	if ((attr & MT_USER) == 0) {
 		/* No access from EL0. */
 		data_access = SP_MEMORY_ATTRIBUTES_ACCESS_NOACCESS;
 	} else {
 		if ((attr & MT_RW) != 0) {
 			assert(MT_TYPE(attr) != MT_DEVICE);
 			data_access = SP_MEMORY_ATTRIBUTES_ACCESS_RW;
 		} else {
 			data_access = SP_MEMORY_ATTRIBUTES_ACCESS_RO;
 		}
 	}

 	smc_attr |= (data_access & SP_MEMORY_ATTRIBUTES_ACCESS_MASK)
 		    << SP_MEMORY_ATTRIBUTES_ACCESS_SHIFT;

 	if (attr & MT_EXECUTE_NEVER) {
 		smc_attr |= SP_MEMORY_ATTRIBUTES_NON_EXEC;
 	}

 	return smc_attr;
 }

 static int spm_memory_attributes_get_smc_handler(uintptr_t base_va)
 {
 	spin_lock(&mem_attr_smc_lock);

 	mmap_attr_t attributes;
 	int rc = get_mem_attributes(secure_partition_xlat_ctx_handle,
 				     base_va, &attributes);

 	spin_unlock(&mem_attr_smc_lock);

 	/* Convert error codes of get_mem_attributes() into SPM ones. */
 	assert(rc == 0 || rc == -EINVAL);

 	if (rc == 0) {
 		return smc_mmap_to_smc_attr(attributes);
 	} else {
 		return SPM_INVALID_PARAMETER;
 	}
 }

 static int spm_memory_attributes_set_smc_handler(u_register_t page_address,
 					u_register_t pages_count,
 					u_register_t smc_attributes)
 {
 	uintptr_t base_va = (uintptr_t) page_address;
 	size_t size = (size_t) (pages_count * PAGE_SIZE);
 	unsigned int attributes = (unsigned int) smc_attributes;

 	INFO("  Start address  : 0x%lx\n", base_va);
 	INFO("  Number of pages: %i (%zi bytes)\n", (int) pages_count, size);
 	INFO("  Attributes     : 0x%x\n", attributes);

 	spin_lock(&mem_attr_smc_lock);

 	int ret = change_mem_attributes(secure_partition_xlat_ctx_handle,
 			base_va, size, smc_attr_to_mmap_attr(attributes));

 	spin_unlock(&mem_attr_smc_lock);

 	/* Convert error codes of change_mem_attributes() into SPM ones. */
 	assert(ret == 0 || ret == -EINVAL);

 	return (ret == 0) ? SPM_SUCCESS : SPM_INVALID_PARAMETER;
 }


 uint64_t spm_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)
 {
 	cpu_context_t *ns_cpu_context;
 	unsigned int ns;

 	/* Determine which security state this SMC originated from */
 	ns = is_caller_non_secure(flags);

 	if (ns == SMC_FROM_SECURE) {

 		/* Handle SMCs from Secure world. */

 		switch (smc_fid) {

 		case SPM_VERSION_AARCH32:
 			SMC_RET1(handle, SPM_VERSION_COMPILED);

 		case SP_EVENT_COMPLETE_AARCH64:
 			assert(handle == cm_get_context(SECURE));
 			cm_el1_sysregs_context_save(SECURE);
 			spm_setup_next_eret_into_sel0(handle);

 			if (sp_init_in_progress) {
 				/*
 				 * SPM reports completion. The SPM must have
 				 * initiated the original request through a
 				 * synchronous entry into the secure
 				 * partition. Jump back to the original C
 				 * runtime context.
 				 */
 				spm_synchronous_sp_exit(&sp_ctx, x1);
 				assert(0);
 			}

 			/*
 			 * This is the result from the Secure partition of an
 			 * earlier request. Copy the result into the non-secure
 			 * context, save the secure state and return to the
 			 * non-secure state.
 			 */

 			/* Get a reference to the non-secure context */
 			ns_cpu_context = cm_get_context(NON_SECURE);
 			assert(ns_cpu_context);

 			/* Restore non-secure state */
 			cm_el1_sysregs_context_restore(NON_SECURE);
 			cm_set_next_eret_context(NON_SECURE);

 			/* Return to normal world */
 			SMC_RET1(ns_cpu_context, x1);

 		case SP_MEMORY_ATTRIBUTES_GET_AARCH64:
 			INFO("Received SP_MEMORY_ATTRIBUTES_GET_AARCH64 SMC\n");

 			if (!sp_init_in_progress) {
 				WARN("SP_MEMORY_ATTRIBUTES_GET_AARCH64 is available at boot time only\n");
 				SMC_RET1(handle, SPM_NOT_SUPPORTED);
 			}
 			SMC_RET1(handle, spm_memory_attributes_get_smc_handler(x1));

 		case SP_MEMORY_ATTRIBUTES_SET_AARCH64:
 			INFO("Received SP_MEMORY_ATTRIBUTES_SET_AARCH64 SMC\n");

 			if (!sp_init_in_progress) {
 				WARN("SP_MEMORY_ATTRIBUTES_SET_AARCH64 is available at boot time only\n");
 				SMC_RET1(handle, SPM_NOT_SUPPORTED);
 			}
 			SMC_RET1(handle, spm_memory_attributes_set_smc_handler(x1, x2, x3));
 		default:
 			break;
 		}
 	} else {

 		/* Handle SMCs from Non-secure world. */

 		switch (smc_fid) {

 		case SP_VERSION_AARCH64:
 		case SP_VERSION_AARCH32:
 			SMC_RET1(handle, SP_VERSION_COMPILED);

 		case MM_COMMUNICATE_AARCH32:
 		case MM_COMMUNICATE_AARCH64:
 		{
 			uint64_t mm_cookie = x1;
 			uint64_t comm_buffer_address = x2;
 			uint64_t comm_size_address = x3;

 			/* Cookie. Reserved for future use. It must be zero. */
 			if (mm_cookie != 0) {
 				ERROR("MM_COMMUNICATE: cookie is not zero\n");
 				SMC_RET1(handle, SPM_INVALID_PARAMETER);
 			}

 			if (comm_buffer_address == 0) {
 				ERROR("MM_COMMUNICATE: comm_buffer_address is zero\n");
 				SMC_RET1(handle, SPM_INVALID_PARAMETER);
 			}

 			if (comm_size_address != 0) {
 				VERBOSE("MM_COMMUNICATE: comm_size_address is not 0 as recommended.\n");
 			}

 			/* Save the Normal world context */
 			cm_el1_sysregs_context_save(NON_SECURE);

 			/*
 			 * Restore the secure world context and prepare for
 			 * entry in S-EL0
 			 */
 			assert(&sp_ctx.cpu_ctx == cm_get_context(SECURE));
 			cm_el1_sysregs_context_restore(SECURE);
 			cm_set_next_eret_context(SECURE);

 			SMC_RET4(&sp_ctx.cpu_ctx, smc_fid, comm_buffer_address,
 				 comm_size_address, plat_my_core_pos());
 		}

 		case SP_MEMORY_ATTRIBUTES_GET_AARCH64:
 		case SP_MEMORY_ATTRIBUTES_SET_AARCH64:
 			/* SMC interfaces reserved for secure callers. */
 			SMC_RET1(handle, SPM_NOT_SUPPORTED);

 		default:
 			break;
 		}
 	}

 	SMC_RET1(handle, SMC_UNK);
 }
	/*
	* Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
	*
	* SPDX-License-Identifier: BSD-3-Clause
	*/

	#include <arch_helpers.h>
	#include <assert.h>
	#include <bl31.h>
	#include <context_mgmt.h>
	#include <debug.h>
	#include <errno.h>
	#include <platform.h>
	#include <runtime_svc.h>
	#include <secure_partition.h>
	#include <smcc.h>
	#include <smcc_helpers.h>
	#include <spinlock.h>
	#include <spm_svc.h>
	#include <utils.h>
	#include <xlat_tables_v2.h>

	#include "spm_private.h"

	/* Lock used for SP_MEMORY_ATTRIBUTES_GET and SP_MEMORY_ATTRIBUTES_SET */
	static spinlock_t mem_attr_smc_lock;

	/*******************************************************************************
	* Secure Partition context information.
	******************************************************************************/
	static secure_partition_context_t sp_ctx;
	unsigned int sp_init_in_progress;

	/*******************************************************************************
	* Replace the S-EL1 re-entry information with S-EL0 re-entry
	* information
	******************************************************************************/
	void spm_setup_next_eret_into_sel0(cpu_context_t *secure_context)
	{
	assert(secure_context == cm_get_context(SECURE));

	cm_set_elr_spsr_el3(SECURE, read_elr_el1(), read_spsr_el1());
	}

	/*******************************************************************************
	* This function takes an SP context pointer and:
	* 1. Applies the S-EL1 system register context from sp_ctx->cpu_ctx.
	* 2. Saves the current C runtime state (callee-saved registers) on the stack
	* frame and saves a reference to this state.
	* 3. Calls el3_exit() so that the EL3 system and general purpose registers
	* from the sp_ctx->cpu_ctx are used to enter the secure partition image.
	******************************************************************************/
	static uint64_t spm_synchronous_sp_entry(secure_partition_context_t *sp_ctx_ptr)
	{
	uint64_t rc;

	assert(sp_ctx_ptr != NULL);
	assert(sp_ctx_ptr->c_rt_ctx == 0);
	assert(cm_get_context(SECURE) == &sp_ctx_ptr->cpu_ctx);

	/* Apply the Secure EL1 system register context and switch to it */
	cm_el1_sysregs_context_restore(SECURE);
	cm_set_next_eret_context(SECURE);

	VERBOSE("%s: We're about to enter the Secure partition...\n", __func__);

	rc = spm_secure_partition_enter(&sp_ctx_ptr->c_rt_ctx);
	#if ENABLE_ASSERTIONS
	sp_ctx_ptr->c_rt_ctx = 0;
	#endif

	return rc;
	}


	/*******************************************************************************
	* This function takes a Secure partition context pointer and:
	* 1. Saves the S-EL1 system register context to sp_ctx->cpu_ctx.
	* 2. Restores the current C runtime state (callee saved registers) from the
	* stack frame using the reference to this state saved in
	* spm_secure_partition_enter().
	* 3. It does not need to save any general purpose or EL3 system register state
	* as the generic smc entry routine should have saved those.
	******************************************************************************/
	static void __dead2 spm_synchronous_sp_exit(
	secure_partition_context_t *sp_ctx_ptr, uint64_t ret)
	{
	assert(sp_ctx_ptr != NULL);
	/* Save the Secure EL1 system register context */
	assert(cm_get_context(SECURE) == &sp_ctx_ptr->cpu_ctx);
	cm_el1_sysregs_context_save(SECURE);

	assert(sp_ctx_ptr->c_rt_ctx != 0);
	spm_secure_partition_exit(sp_ctx_ptr->c_rt_ctx, ret);

	/* Should never reach here */
	assert(0);
	}

	/*******************************************************************************
	* This function passes control to the Secure Partition image (BL32) for the
	* first time on the primary cpu after a cold boot. It assumes that a valid
	* secure context has already been created by spm_setup() which can be directly
	* used. This function performs a synchronous entry into the Secure partition.
	* The SP passes control back to this routine through a SMC.
	******************************************************************************/
	int32_t spm_init(void)
	{
	entry_point_info_t *secure_partition_ep_info;
	uint64_t rc;

	VERBOSE("%s entry\n", __func__);

	/*
	* Get information about the Secure Partition (BL32) image. Its
	* absence is a critical failure.
	*/
	secure_partition_ep_info = bl31_plat_get_next_image_ep_info(SECURE);
	assert(secure_partition_ep_info);

	/*
	* Initialise the common context and then overlay the S-EL0 specific
	* context on top of it.
	*/
	cm_init_my_context(secure_partition_ep_info);
	secure_partition_setup();

	/*
	* Arrange for an entry into the secure partition.
	*/
	sp_init_in_progress = 1;
	rc = spm_synchronous_sp_entry(&sp_ctx);
	assert(rc == 0);
	sp_init_in_progress = 0;
	VERBOSE("SP_MEMORY_ATTRIBUTES_SET_AARCH64 availability has been revoked\n");

	return rc;
	}

	/*******************************************************************************
	* Given a secure partition entrypoint info pointer, entry point PC & pointer to
	* a context data structure, this function will initialize the SPM context and
	* entry point info for the secure partition.
	******************************************************************************/
	void spm_init_sp_ep_state(struct entry_point_info *sp_ep_info,
	uint64_t pc,
	secure_partition_context_t *sp_ctx_ptr)
	{
	uint32_t ep_attr;

	assert(sp_ep_info);
	assert(pc);
	assert(sp_ctx_ptr);

	cm_set_context(&sp_ctx_ptr->cpu_ctx, SECURE);

	/* initialise an entrypoint to set up the CPU context */
	ep_attr = SECURE \| EP_ST_ENABLE;
	if (read_sctlr_el3() & SCTLR_EE_BIT)
	ep_attr \|= EP_EE_BIG;
	SET_PARAM_HEAD(sp_ep_info, PARAM_EP, VERSION_1, ep_attr);

	sp_ep_info->pc = pc;
	/* The secure partition runs in S-EL0. */
	sp_ep_info->spsr = SPSR_64(MODE_EL0,
	MODE_SP_EL0,
	DISABLE_ALL_EXCEPTIONS);

	zeromem(&sp_ep_info->args, sizeof(sp_ep_info->args));
	}

	/*******************************************************************************
	* Secure Partition Manager setup. The SPM finds out the SP entrypoint if not
	* already known and initialises the context for entry into the SP for its
	* initialisation.
	******************************************************************************/
	int32_t spm_setup(void)
	{
	entry_point_info_t *secure_partition_ep_info;

	VERBOSE("%s entry\n", __func__);

	/*
	* Get information about the Secure Partition (BL32) image. Its
	* absence is a critical failure.
	*/
	secure_partition_ep_info = bl31_plat_get_next_image_ep_info(SECURE);
	if (!secure_partition_ep_info) {
	WARN("No SPM provided by BL2 boot loader, Booting device"
	" without SPM initialization. SMCs destined for SPM"
	" will return SMC_UNK\n");
	return 1;
	}

	/*
	* If there's no valid entry point for SP, we return a non-zero value
	* signalling failure initializing the service. We bail out without
	* registering any handlers
	*/
	if (!secure_partition_ep_info->pc) {
	return 1;
	}

	spm_init_sp_ep_state(secure_partition_ep_info,
	secure_partition_ep_info->pc,
	&sp_ctx);

	/*
	* All SPM initialization done. Now register our init function with
	* BL31 for deferred invocation
	*/
	bl31_register_bl32_init(&spm_init);

	VERBOSE("%s exit\n", __func__);

	return 0;
	}

	/*
	* Attributes are encoded using a different format in the SMC interface than in
	* the Trusted Firmware, where the mmap_attr_t enum type is used. This function
	* converts an attributes value from the SMC format to the mmap_attr_t format by
	* setting MT_RW/MT_RO, MT_USER/MT_PRIVILEGED and MT_EXECUTE/MT_EXECUTE_NEVER.
	* The other fields are left as 0 because they are ignored by the function
	* change_mem_attributes().
	*/
	static mmap_attr_t smc_attr_to_mmap_attr(unsigned int attributes)
	{
	mmap_attr_t tf_attr = 0;

	unsigned int access = (attributes & SP_MEMORY_ATTRIBUTES_ACCESS_MASK)
	>> SP_MEMORY_ATTRIBUTES_ACCESS_SHIFT;

	if (access == SP_MEMORY_ATTRIBUTES_ACCESS_RW) {
	tf_attr \|= MT_RW \| MT_USER;
	} else if (access == SP_MEMORY_ATTRIBUTES_ACCESS_RO) {
	tf_attr \|= MT_RO \| MT_USER;
	} else {
	/* Other values are reserved. */
	assert(access == SP_MEMORY_ATTRIBUTES_ACCESS_NOACCESS);
	/* The only requirement is that there's no access from EL0 */
	tf_attr \|= MT_RO \| MT_PRIVILEGED;
	}

	if ((attributes & SP_MEMORY_ATTRIBUTES_NON_EXEC) == 0) {
	tf_attr \|= MT_EXECUTE;
	} else {
	tf_attr \|= MT_EXECUTE_NEVER;
	}

	return tf_attr;
	}

	/*
	* This function converts attributes from the Trusted Firmware format into the
	* SMC interface format.
	*/
	static int smc_mmap_to_smc_attr(mmap_attr_t attr)
	{
	int smc_attr = 0;

	int data_access;

	if ((attr & MT_USER) == 0) {
	/* No access from EL0. */
	data_access = SP_MEMORY_ATTRIBUTES_ACCESS_NOACCESS;
	} else {
	if ((attr & MT_RW) != 0) {
	assert(MT_TYPE(attr) != MT_DEVICE);
	data_access = SP_MEMORY_ATTRIBUTES_ACCESS_RW;
	} else {
	data_access = SP_MEMORY_ATTRIBUTES_ACCESS_RO;
	}
	}

	smc_attr \|= (data_access & SP_MEMORY_ATTRIBUTES_ACCESS_MASK)
	<< SP_MEMORY_ATTRIBUTES_ACCESS_SHIFT;

	if (attr & MT_EXECUTE_NEVER) {
	smc_attr \|= SP_MEMORY_ATTRIBUTES_NON_EXEC;
	}

	return smc_attr;
	}

	static int spm_memory_attributes_get_smc_handler(uintptr_t base_va)
	{
	spin_lock(&mem_attr_smc_lock);

	mmap_attr_t attributes;
	int rc = get_mem_attributes(secure_partition_xlat_ctx_handle,
	base_va, &attributes);

	spin_unlock(&mem_attr_smc_lock);

	/* Convert error codes of get_mem_attributes() into SPM ones. */
	assert(rc == 0 \|\| rc == -EINVAL);

	if (rc == 0) {
	return smc_mmap_to_smc_attr(attributes);
	} else {
	return SPM_INVALID_PARAMETER;
	}
	}

	static int spm_memory_attributes_set_smc_handler(u_register_t page_address,
	u_register_t pages_count,
	u_register_t smc_attributes)
	{
	uintptr_t base_va = (uintptr_t) page_address;
	size_t size = (size_t) (pages_count * PAGE_SIZE);
	unsigned int attributes = (unsigned int) smc_attributes;

	INFO(" Start address : 0x%lx\n", base_va);
	INFO(" Number of pages: %i (%zi bytes)\n", (int) pages_count, size);
	INFO(" Attributes : 0x%x\n", attributes);

	spin_lock(&mem_attr_smc_lock);

	int ret = change_mem_attributes(secure_partition_xlat_ctx_handle,
	base_va, size, smc_attr_to_mmap_attr(attributes));

	spin_unlock(&mem_attr_smc_lock);

	/* Convert error codes of change_mem_attributes() into SPM ones. */
	assert(ret == 0 \|\| ret == -EINVAL);

	return (ret == 0) ? SPM_SUCCESS : SPM_INVALID_PARAMETER;
	}


	uint64_t spm_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)
	{
	cpu_context_t *ns_cpu_context;
	unsigned int ns;

	/* Determine which security state this SMC originated from */
	ns = is_caller_non_secure(flags);

	if (ns == SMC_FROM_SECURE) {

	/* Handle SMCs from Secure world. */

	switch (smc_fid) {

	case SPM_VERSION_AARCH32:
	SMC_RET1(handle, SPM_VERSION_COMPILED);

	case SP_EVENT_COMPLETE_AARCH64:
	assert(handle == cm_get_context(SECURE));
	cm_el1_sysregs_context_save(SECURE);
	spm_setup_next_eret_into_sel0(handle);

	if (sp_init_in_progress) {
	/*
	* SPM reports completion. The SPM must have
	* initiated the original request through a
	* synchronous entry into the secure
	* partition. Jump back to the original C
	* runtime context.
	*/
	spm_synchronous_sp_exit(&sp_ctx, x1);
	assert(0);
	}

	/*
	* This is the result from the Secure partition of an
	* earlier request. Copy the result into the non-secure
	* context, save the secure state and return to the
	* non-secure state.
	*/

	/* Get a reference to the non-secure context */
	ns_cpu_context = cm_get_context(NON_SECURE);
	assert(ns_cpu_context);

	/* Restore non-secure state */
	cm_el1_sysregs_context_restore(NON_SECURE);
	cm_set_next_eret_context(NON_SECURE);

	/* Return to normal world */
	SMC_RET1(ns_cpu_context, x1);

	case SP_MEMORY_ATTRIBUTES_GET_AARCH64:
	INFO("Received SP_MEMORY_ATTRIBUTES_GET_AARCH64 SMC\n");

	if (!sp_init_in_progress) {
	WARN("SP_MEMORY_ATTRIBUTES_GET_AARCH64 is available at boot time only\n");
	SMC_RET1(handle, SPM_NOT_SUPPORTED);
	}
	SMC_RET1(handle, spm_memory_attributes_get_smc_handler(x1));

	case SP_MEMORY_ATTRIBUTES_SET_AARCH64:
	INFO("Received SP_MEMORY_ATTRIBUTES_SET_AARCH64 SMC\n");

	if (!sp_init_in_progress) {
	WARN("SP_MEMORY_ATTRIBUTES_SET_AARCH64 is available at boot time only\n");
	SMC_RET1(handle, SPM_NOT_SUPPORTED);
	}
	SMC_RET1(handle, spm_memory_attributes_set_smc_handler(x1, x2, x3));
	default:
	break;
	}
	} else {

	/* Handle SMCs from Non-secure world. */

	switch (smc_fid) {

	case SP_VERSION_AARCH64:
	case SP_VERSION_AARCH32:
	SMC_RET1(handle, SP_VERSION_COMPILED);

	case MM_COMMUNICATE_AARCH32:
	case MM_COMMUNICATE_AARCH64:
	{
	uint64_t mm_cookie = x1;
	uint64_t comm_buffer_address = x2;
	uint64_t comm_size_address = x3;

	/* Cookie. Reserved for future use. It must be zero. */
	if (mm_cookie != 0) {
	ERROR("MM_COMMUNICATE: cookie is not zero\n");
	SMC_RET1(handle, SPM_INVALID_PARAMETER);
	}

	if (comm_buffer_address == 0) {
	ERROR("MM_COMMUNICATE: comm_buffer_address is zero\n");
	SMC_RET1(handle, SPM_INVALID_PARAMETER);
	}

	if (comm_size_address != 0) {
	VERBOSE("MM_COMMUNICATE: comm_size_address is not 0 as recommended.\n");
	}

	/* Save the Normal world context */
	cm_el1_sysregs_context_save(NON_SECURE);

	/*
	* Restore the secure world context and prepare for
	* entry in S-EL0
	*/
	assert(&sp_ctx.cpu_ctx == cm_get_context(SECURE));
	cm_el1_sysregs_context_restore(SECURE);
	cm_set_next_eret_context(SECURE);

	SMC_RET4(&sp_ctx.cpu_ctx, smc_fid, comm_buffer_address,
	comm_size_address, plat_my_core_pos());
	}

	case SP_MEMORY_ATTRIBUTES_GET_AARCH64:
	case SP_MEMORY_ATTRIBUTES_SET_AARCH64:
	/* SMC interfaces reserved for secure callers. */
	SMC_RET1(handle, SPM_NOT_SUPPORTED);

	default:
	break;
	}
	}

	SMC_RET1(handle, SMC_UNK);
	}