lib/xlat_tables_v2/xlat_tables_utils.c - filogic/atf - Gitiles

 /*
  * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */

 #include <arch_helpers.h>
 #include <assert.h>
 #include <debug.h>
 #include <errno.h>
 #include <platform_def.h>
 #include <stdbool.h>
 #include <types.h>
 #include <utils_def.h>
 #include <xlat_tables_defs.h>
 #include <xlat_tables_v2.h>

 #include "xlat_tables_private.h"

 #if LOG_LEVEL < LOG_LEVEL_VERBOSE

 void xlat_mmap_print(__unused const mmap_region_t *mmap)
 {
 	/* Empty */
 }

 void xlat_tables_print(__unused xlat_ctx_t *ctx)
 {
 	/* Empty */
 }

 #else /* if LOG_LEVEL >= LOG_LEVEL_VERBOSE */

 void xlat_mmap_print(const mmap_region_t *mmap)
 {
 	tf_printf("mmap:\n");
 	const mmap_region_t *mm = mmap;

 	while (mm->size != 0U) {
 		tf_printf(" VA:0x%lx  PA:0x%llx  size:0x%zx  attr:0x%x "
 			  "granularity:0x%zx\n", mm->base_va, mm->base_pa,
 			  mm->size, mm->attr, mm->granularity);
 		++mm;
 	};
 	tf_printf("\n");
 }

 /* Print the attributes of the specified block descriptor. */
 static void xlat_desc_print(const xlat_ctx_t *ctx, uint64_t desc)
 {
 	uint64_t mem_type_index = ATTR_INDEX_GET(desc);
 	int xlat_regime = ctx->xlat_regime;

 	if (mem_type_index == ATTR_IWBWA_OWBWA_NTR_INDEX) {
 		tf_printf("MEM");
 	} else if (mem_type_index == ATTR_NON_CACHEABLE_INDEX) {
 		tf_printf("NC");
 	} else {
 		assert(mem_type_index == ATTR_DEVICE_INDEX);
 		tf_printf("DEV");
 	}

 	if ((xlat_regime == EL3_REGIME) || (xlat_regime == EL2_REGIME)) {
 		/* For EL3 and EL2 only check the AP[2] and XN bits. */
 		tf_printf(((desc & LOWER_ATTRS(AP_RO)) != 0ULL) ? "-RO" : "-RW");
 		tf_printf(((desc & UPPER_ATTRS(XN)) != 0ULL) ? "-XN" : "-EXEC");
 	} else {
 		assert(xlat_regime == EL1_EL0_REGIME);
 		/*
 		 * For EL0 and EL1:
 		 * - In AArch64 PXN and UXN can be set independently but in
 		 *   AArch32 there is no UXN (XN affects both privilege levels).
 		 *   For consistency, we set them simultaneously in both cases.
 		 * - RO and RW permissions must be the same in EL1 and EL0. If
 		 *   EL0 can access that memory region, so can EL1, with the
 		 *   same permissions.
 		 */
 #if ENABLE_ASSERTIONS
 		uint64_t xn_mask = xlat_arch_regime_get_xn_desc(EL1_EL0_REGIME);
 		uint64_t xn_perm = desc & xn_mask;

 		assert((xn_perm == xn_mask) || (xn_perm == 0ULL));
 #endif
 		tf_printf(((desc & LOWER_ATTRS(AP_RO)) != 0ULL) ? "-RO" : "-RW");
 		/* Only check one of PXN and UXN, the other one is the same. */
 		tf_printf(((desc & UPPER_ATTRS(PXN)) != 0ULL) ? "-XN" : "-EXEC");
 		/*
 		 * Privileged regions can only be accessed from EL1, user
 		 * regions can be accessed from EL1 and EL0.
 		 */
 		tf_printf(((desc & LOWER_ATTRS(AP_ACCESS_UNPRIVILEGED)) != 0ULL)
 			  ? "-USER" : "-PRIV");
 	}

 	tf_printf(((LOWER_ATTRS(NS) & desc) != 0ULL) ? "-NS" : "-S");
 }

 static const char * const level_spacers[] = {
 	"[LV0] ",
 	"  [LV1] ",
 	"    [LV2] ",
 	"      [LV3] "
 };

 static const char *invalid_descriptors_ommited =
 		"%s(%d invalid descriptors omitted)\n";

 /*
  * Recursive function that reads the translation tables passed as an argument
  * and prints their status.
  */
 static void xlat_tables_print_internal(xlat_ctx_t *ctx, uintptr_t table_base_va,
 		const uint64_t *table_base, unsigned int table_entries,
 		unsigned int level)
 {
 	assert(level <= XLAT_TABLE_LEVEL_MAX);

 	uint64_t desc;
 	uintptr_t table_idx_va = table_base_va;
 	unsigned int table_idx = 0U;
 	size_t level_size = XLAT_BLOCK_SIZE(level);

 	/*
 	 * Keep track of how many invalid descriptors are counted in a row.
 	 * Whenever multiple invalid descriptors are found, only the first one
 	 * is printed, and a line is added to inform about how many descriptors
 	 * have been omitted.
 	 */
 	int invalid_row_count = 0;

 	while (table_idx < table_entries) {

 		desc = table_base[table_idx];

 		if ((desc & DESC_MASK) == INVALID_DESC) {

 			if (invalid_row_count == 0) {
 				tf_printf("%sVA:0x%lx size:0x%zx\n",
 					  level_spacers[level],
 					  table_idx_va, level_size);
 			}
 			invalid_row_count++;

 		} else {

 			if (invalid_row_count > 1) {
 				tf_printf(invalid_descriptors_ommited,
 					  level_spacers[level],
 					  invalid_row_count - 1);
 			}
 			invalid_row_count = 0;

 			/*
 			 * Check if this is a table or a block. Tables are only
 			 * allowed in levels other than 3, but DESC_PAGE has the
 			 * same value as DESC_TABLE, so we need to check.
 			 */
 			if (((desc & DESC_MASK) == TABLE_DESC) &&
 					(level < XLAT_TABLE_LEVEL_MAX)) {
 				/*
 				 * Do not print any PA for a table descriptor,
 				 * as it doesn't directly map physical memory
 				 * but instead points to the next translation
 				 * table in the translation table walk.
 				 */
 				tf_printf("%sVA:0x%lx size:0x%zx\n",
 					  level_spacers[level],
 					  table_idx_va, level_size);

 				uintptr_t addr_inner = desc & TABLE_ADDR_MASK;

 				xlat_tables_print_internal(ctx, table_idx_va,
 					(uint64_t *)addr_inner,
 					XLAT_TABLE_ENTRIES, level + 1U);
 			} else {
 				tf_printf("%sVA:0x%lx PA:0x%llx size:0x%zx ",
 					  level_spacers[level],
 					  table_idx_va,
 					  (uint64_t)(desc & TABLE_ADDR_MASK),
 					  level_size);
 				xlat_desc_print(ctx, desc);
 				tf_printf("\n");
 			}
 		}

 		table_idx++;
 		table_idx_va += level_size;
 	}

 	if (invalid_row_count > 1) {
 		tf_printf(invalid_descriptors_ommited,
 			  level_spacers[level], invalid_row_count - 1);
 	}
 }

 void xlat_tables_print(xlat_ctx_t *ctx)
 {
 	const char *xlat_regime_str;
 	int used_page_tables;

 	if (ctx->xlat_regime == EL1_EL0_REGIME) {
 		xlat_regime_str = "1&0";
 	} else if (ctx->xlat_regime == EL2_REGIME) {
 		xlat_regime_str = "2";
 	} else {
 		assert(ctx->xlat_regime == EL3_REGIME);
 		xlat_regime_str = "3";
 	}
 	VERBOSE("Translation tables state:\n");
 	VERBOSE("  Xlat regime:     EL%s\n", xlat_regime_str);
 	VERBOSE("  Max allowed PA:  0x%llx\n", ctx->pa_max_address);
 	VERBOSE("  Max allowed VA:  0x%lx\n", ctx->va_max_address);
 	VERBOSE("  Max mapped PA:   0x%llx\n", ctx->max_pa);
 	VERBOSE("  Max mapped VA:   0x%lx\n", ctx->max_va);

 	VERBOSE("  Initial lookup level: %u\n", ctx->base_level);
 	VERBOSE("  Entries @initial lookup level: %u\n",
 		ctx->base_table_entries);

 #if PLAT_XLAT_TABLES_DYNAMIC
 	used_page_tables = 0;
 	for (int i = 0; i < ctx->tables_num; ++i) {
 		if (ctx->tables_mapped_regions[i] != 0)
 			++used_page_tables;
 	}
 #else
 	used_page_tables = ctx->next_table;
 #endif
 	VERBOSE("  Used %d sub-tables out of %d (spare: %d)\n",
 		used_page_tables, ctx->tables_num,
 		ctx->tables_num - used_page_tables);

 	xlat_tables_print_internal(ctx, 0U, ctx->base_table,
 				   ctx->base_table_entries, ctx->base_level);
 }

 #endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */

 /*
  * Do a translation table walk to find the block or page descriptor that maps
  * virtual_addr.
  *
  * On success, return the address of the descriptor within the translation
  * table. Its lookup level is stored in '*out_level'.
  * On error, return NULL.
  *
  * xlat_table_base
  *   Base address for the initial lookup level.
  * xlat_table_base_entries
  *   Number of entries in the translation table for the initial lookup level.
  * virt_addr_space_size
  *   Size in bytes of the virtual address space.
  */
 static uint64_t *find_xlat_table_entry(uintptr_t virtual_addr,
 				       void *xlat_table_base,
 				       unsigned int xlat_table_base_entries,
 				       unsigned long long virt_addr_space_size,
 				       unsigned int *out_level)
 {
 	unsigned int start_level;
 	uint64_t *table;
 	unsigned int entries;

 	start_level = GET_XLAT_TABLE_LEVEL_BASE(virt_addr_space_size);

 	table = xlat_table_base;
 	entries = xlat_table_base_entries;

 	for (unsigned int level = start_level;
 	     level <= XLAT_TABLE_LEVEL_MAX;
 	     ++level) {
 		uint64_t idx, desc, desc_type;

 		idx = XLAT_TABLE_IDX(virtual_addr, level);
 		if (idx >= entries) {
 			WARN("Missing xlat table entry at address 0x%lx\n",
 			     virtual_addr);
 			return NULL;
 		}

 		desc = table[idx];
 		desc_type = desc & DESC_MASK;

 		if (desc_type == INVALID_DESC) {
 			VERBOSE("Invalid entry (memory not mapped)\n");
 			return NULL;
 		}

 		if (level == XLAT_TABLE_LEVEL_MAX) {
 			/*
 			 * Only page descriptors allowed at the final lookup
 			 * level.
 			 */
 			assert(desc_type == PAGE_DESC);
 			*out_level = level;
 			return &table[idx];
 		}

 		if (desc_type == BLOCK_DESC) {
 			*out_level = level;
 			return &table[idx];
 		}

 		assert(desc_type == TABLE_DESC);
 		table = (uint64_t *)(uintptr_t)(desc & TABLE_ADDR_MASK);
 		entries = XLAT_TABLE_ENTRIES;
 	}

 	/*
 	 * This shouldn't be reached, the translation table walk should end at
 	 * most at level XLAT_TABLE_LEVEL_MAX and return from inside the loop.
 	 */
 	assert(false);

 	return NULL;
 }


 static int xlat_get_mem_attributes_internal(const xlat_ctx_t *ctx,
 		uintptr_t base_va, uint32_t *attributes, uint64_t **table_entry,
 		unsigned long long *addr_pa, unsigned int *table_level)
 {
 	uint64_t *entry;
 	uint64_t desc;
 	unsigned int level;
 	unsigned long long virt_addr_space_size;

 	/*
 	 * Sanity-check arguments.
 	 */
 	assert(ctx != NULL);
 	assert(ctx->initialized);
 	assert((ctx->xlat_regime == EL1_EL0_REGIME) ||
 	       (ctx->xlat_regime == EL2_REGIME) ||
 	       (ctx->xlat_regime == EL3_REGIME));

 	virt_addr_space_size = (unsigned long long)ctx->va_max_address + 1ULL;
 	assert(virt_addr_space_size > 0U);

 	entry = find_xlat_table_entry(base_va,
 				ctx->base_table,
 				ctx->base_table_entries,
 				virt_addr_space_size,
 				&level);
 	if (entry == NULL) {
 		WARN("Address 0x%lx is not mapped.\n", base_va);
 		return -EINVAL;
 	}

 	if (addr_pa != NULL) {
 		*addr_pa = *entry & TABLE_ADDR_MASK;
 	}

 	if (table_entry != NULL) {
 		*table_entry = entry;
 	}

 	if (table_level != NULL) {
 		*table_level = level;
 	}

 	desc = *entry;

 #if LOG_LEVEL >= LOG_LEVEL_VERBOSE
 	VERBOSE("Attributes: ");
 	xlat_desc_print(ctx, desc);
 	tf_printf("\n");
 #endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */

 	assert(attributes != NULL);
 	*attributes = 0U;

 	uint64_t attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;

 	if (attr_index == ATTR_IWBWA_OWBWA_NTR_INDEX) {
 		*attributes |= MT_MEMORY;
 	} else if (attr_index == ATTR_NON_CACHEABLE_INDEX) {
 		*attributes |= MT_NON_CACHEABLE;
 	} else {
 		assert(attr_index == ATTR_DEVICE_INDEX);
 		*attributes |= MT_DEVICE;
 	}

 	uint64_t ap2_bit = (desc >> AP2_SHIFT) & 1U;

 	if (ap2_bit == AP2_RW)
 		*attributes |= MT_RW;

 	if (ctx->xlat_regime == EL1_EL0_REGIME) {
 		uint64_t ap1_bit = (desc >> AP1_SHIFT) & 1U;

 		if (ap1_bit == AP1_ACCESS_UNPRIVILEGED)
 			*attributes |= MT_USER;
 	}

 	uint64_t ns_bit = (desc >> NS_SHIFT) & 1U;

 	if (ns_bit == 1U)
 		*attributes |= MT_NS;

 	uint64_t xn_mask = xlat_arch_regime_get_xn_desc(ctx->xlat_regime);

 	if ((desc & xn_mask) == xn_mask) {
 		*attributes |= MT_EXECUTE_NEVER;
 	} else {
 		assert((desc & xn_mask) == 0U);
 	}

 	return 0;
 }


 int xlat_get_mem_attributes_ctx(const xlat_ctx_t *ctx, uintptr_t base_va,
 				uint32_t *attr)
 {
 	return xlat_get_mem_attributes_internal(ctx, base_va, attr,
 				NULL, NULL, NULL);
 }


 int xlat_change_mem_attributes_ctx(const xlat_ctx_t *ctx, uintptr_t base_va,
 				   size_t size, uint32_t attr)
 {
 	/* Note: This implementation isn't optimized. */

 	assert(ctx != NULL);
 	assert(ctx->initialized);

 	unsigned long long virt_addr_space_size =
 		(unsigned long long)ctx->va_max_address + 1U;
 	assert(virt_addr_space_size > 0U);

 	if (!IS_PAGE_ALIGNED(base_va)) {
 		WARN("%s: Address 0x%lx is not aligned on a page boundary.\n",
 		     __func__, base_va);
 		return -EINVAL;
 	}

 	if (size == 0U) {
 		WARN("%s: Size is 0.\n", __func__);
 		return -EINVAL;
 	}

 	if ((size % PAGE_SIZE) != 0U) {
 		WARN("%s: Size 0x%zx is not a multiple of a page size.\n",
 		     __func__, size);
 		return -EINVAL;
 	}

 	if (((attr & MT_EXECUTE_NEVER) == 0U) && ((attr & MT_RW) != 0U)) {
 		WARN("%s: Mapping memory as read-write and executable not allowed.\n",
 		     __func__);
 		return -EINVAL;
 	}

 	size_t pages_count = size / PAGE_SIZE;

 	VERBOSE("Changing memory attributes of %zu pages starting from address 0x%lx...\n",
 		pages_count, base_va);

 	uintptr_t base_va_original = base_va;

 	/*
 	 * Sanity checks.
 	 */
 	for (size_t i = 0U; i < pages_count; ++i) {
 		const uint64_t *entry;
 		uint64_t desc, attr_index;
 		unsigned int level;

 		entry = find_xlat_table_entry(base_va,
 					      ctx->base_table,
 					      ctx->base_table_entries,
 					      virt_addr_space_size,
 					      &level);
 		if (entry == NULL) {
 			WARN("Address 0x%lx is not mapped.\n", base_va);
 			return -EINVAL;
 		}

 		desc = *entry;

 		/*
 		 * Check that all the required pages are mapped at page
 		 * granularity.
 		 */
 		if (((desc & DESC_MASK) != PAGE_DESC) ||
 			(level != XLAT_TABLE_LEVEL_MAX)) {
 			WARN("Address 0x%lx is not mapped at the right granularity.\n",
 			     base_va);
 			WARN("Granularity is 0x%llx, should be 0x%x.\n",
 			     (unsigned long long)XLAT_BLOCK_SIZE(level), PAGE_SIZE);
 			return -EINVAL;
 		}

 		/*
 		 * If the region type is device, it shouldn't be executable.
 		 */
 		attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;
 		if (attr_index == ATTR_DEVICE_INDEX) {
 			if ((attr & MT_EXECUTE_NEVER) == 0U) {
 				WARN("Setting device memory as executable at address 0x%lx.",
 				     base_va);
 				return -EINVAL;
 			}
 		}

 		base_va += PAGE_SIZE;
 	}

 	/* Restore original value. */
 	base_va = base_va_original;

 	for (unsigned int i = 0U; i < pages_count; ++i) {

 		uint32_t old_attr = 0U, new_attr;
 		uint64_t *entry = NULL;
 		unsigned int level = 0U;
 		unsigned long long addr_pa = 0ULL;

 		(void) xlat_get_mem_attributes_internal(ctx, base_va, &old_attr,
 					    &entry, &addr_pa, &level);

 		/*
 		 * From attr, only MT_RO/MT_RW, MT_EXECUTE/MT_EXECUTE_NEVER and
 		 * MT_USER/MT_PRIVILEGED are taken into account. Any other
 		 * information is ignored.
 		 */

 		/* Clean the old attributes so that they can be rebuilt. */
 		new_attr = old_attr & ~(MT_RW | MT_EXECUTE_NEVER | MT_USER);

 		/*
 		 * Update attributes, but filter out the ones this function
 		 * isn't allowed to change.
 		 */
 		new_attr |= attr & (MT_RW | MT_EXECUTE_NEVER | MT_USER);

 		/*
 		 * The break-before-make sequence requires writing an invalid
 		 * descriptor and making sure that the system sees the change
 		 * before writing the new descriptor.
 		 */
 		*entry = INVALID_DESC;
 #if !(HW_ASSISTED_COHERENCY || WARMBOOT_ENABLE_DCACHE_EARLY)
 		dccvac((uintptr_t)entry);
 #endif
 		/* Invalidate any cached copy of this mapping in the TLBs. */
 		xlat_arch_tlbi_va(base_va, ctx->xlat_regime);

 		/* Ensure completion of the invalidation. */
 		xlat_arch_tlbi_va_sync();

 		/* Write new descriptor */
 		*entry = xlat_desc(ctx, new_attr, addr_pa, level);
 #if !(HW_ASSISTED_COHERENCY || WARMBOOT_ENABLE_DCACHE_EARLY)
 		dccvac((uintptr_t)entry);
 #endif
 		base_va += PAGE_SIZE;
 	}

 	/* Ensure that the last descriptor writen is seen by the system. */
 	dsbish();

 	return 0;
 }
	/*
	* Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
	*
	* SPDX-License-Identifier: BSD-3-Clause
	*/

	#include <arch_helpers.h>
	#include <assert.h>
	#include <debug.h>
	#include <errno.h>
	#include <platform_def.h>
	#include <stdbool.h>
	#include <types.h>
	#include <utils_def.h>
	#include <xlat_tables_defs.h>
	#include <xlat_tables_v2.h>

	#include "xlat_tables_private.h"

	#if LOG_LEVEL < LOG_LEVEL_VERBOSE

	void xlat_mmap_print(__unused const mmap_region_t *mmap)
	{
	/* Empty */
	}

	void xlat_tables_print(__unused xlat_ctx_t *ctx)
	{
	/* Empty */
	}

	#else /* if LOG_LEVEL >= LOG_LEVEL_VERBOSE */

	void xlat_mmap_print(const mmap_region_t *mmap)
	{
	tf_printf("mmap:\n");
	const mmap_region_t *mm = mmap;

	while (mm->size != 0U) {
	tf_printf(" VA:0x%lx PA:0x%llx size:0x%zx attr:0x%x "
	"granularity:0x%zx\n", mm->base_va, mm->base_pa,
	mm->size, mm->attr, mm->granularity);
	++mm;
	};
	tf_printf("\n");
	}

	/* Print the attributes of the specified block descriptor. */
	static void xlat_desc_print(const xlat_ctx_t *ctx, uint64_t desc)
	{
	uint64_t mem_type_index = ATTR_INDEX_GET(desc);
	int xlat_regime = ctx->xlat_regime;

	if (mem_type_index == ATTR_IWBWA_OWBWA_NTR_INDEX) {
	tf_printf("MEM");
	} else if (mem_type_index == ATTR_NON_CACHEABLE_INDEX) {
	tf_printf("NC");
	} else {
	assert(mem_type_index == ATTR_DEVICE_INDEX);
	tf_printf("DEV");
	}

	if ((xlat_regime == EL3_REGIME) \|\| (xlat_regime == EL2_REGIME)) {
	/* For EL3 and EL2 only check the AP[2] and XN bits. */
	tf_printf(((desc & LOWER_ATTRS(AP_RO)) != 0ULL) ? "-RO" : "-RW");
	tf_printf(((desc & UPPER_ATTRS(XN)) != 0ULL) ? "-XN" : "-EXEC");
	} else {
	assert(xlat_regime == EL1_EL0_REGIME);
	/*
	* For EL0 and EL1:
	* - In AArch64 PXN and UXN can be set independently but in
	* AArch32 there is no UXN (XN affects both privilege levels).
	* For consistency, we set them simultaneously in both cases.
	* - RO and RW permissions must be the same in EL1 and EL0. If
	* EL0 can access that memory region, so can EL1, with the
	* same permissions.
	*/
	#if ENABLE_ASSERTIONS
	uint64_t xn_mask = xlat_arch_regime_get_xn_desc(EL1_EL0_REGIME);
	uint64_t xn_perm = desc & xn_mask;

	assert((xn_perm == xn_mask) \|\| (xn_perm == 0ULL));
	#endif
	tf_printf(((desc & LOWER_ATTRS(AP_RO)) != 0ULL) ? "-RO" : "-RW");
	/* Only check one of PXN and UXN, the other one is the same. */
	tf_printf(((desc & UPPER_ATTRS(PXN)) != 0ULL) ? "-XN" : "-EXEC");
	/*
	* Privileged regions can only be accessed from EL1, user
	* regions can be accessed from EL1 and EL0.
	*/
	tf_printf(((desc & LOWER_ATTRS(AP_ACCESS_UNPRIVILEGED)) != 0ULL)
	? "-USER" : "-PRIV");
	}

	tf_printf(((LOWER_ATTRS(NS) & desc) != 0ULL) ? "-NS" : "-S");
	}

	static const char * const level_spacers[] = {
	"[LV0] ",
	" [LV1] ",
	" [LV2] ",
	" [LV3] "
	};

	static const char *invalid_descriptors_ommited =
	"%s(%d invalid descriptors omitted)\n";

	/*
	* Recursive function that reads the translation tables passed as an argument
	* and prints their status.
	*/
	static void xlat_tables_print_internal(xlat_ctx_t *ctx, uintptr_t table_base_va,
	const uint64_t *table_base, unsigned int table_entries,
	unsigned int level)
	{
	assert(level <= XLAT_TABLE_LEVEL_MAX);

	uint64_t desc;
	uintptr_t table_idx_va = table_base_va;
	unsigned int table_idx = 0U;
	size_t level_size = XLAT_BLOCK_SIZE(level);

	/*
	* Keep track of how many invalid descriptors are counted in a row.
	* Whenever multiple invalid descriptors are found, only the first one
	* is printed, and a line is added to inform about how many descriptors
	* have been omitted.
	*/
	int invalid_row_count = 0;

	while (table_idx < table_entries) {

	desc = table_base[table_idx];

	if ((desc & DESC_MASK) == INVALID_DESC) {

	if (invalid_row_count == 0) {
	tf_printf("%sVA:0x%lx size:0x%zx\n",
	level_spacers[level],
	table_idx_va, level_size);
	}
	invalid_row_count++;

	} else {

	if (invalid_row_count > 1) {
	tf_printf(invalid_descriptors_ommited,
	level_spacers[level],
	invalid_row_count - 1);
	}
	invalid_row_count = 0;

	/*
	* Check if this is a table or a block. Tables are only
	* allowed in levels other than 3, but DESC_PAGE has the
	* same value as DESC_TABLE, so we need to check.
	*/
	if (((desc & DESC_MASK) == TABLE_DESC) &&
	(level < XLAT_TABLE_LEVEL_MAX)) {
	/*
	* Do not print any PA for a table descriptor,
	* as it doesn't directly map physical memory
	* but instead points to the next translation
	* table in the translation table walk.
	*/
	tf_printf("%sVA:0x%lx size:0x%zx\n",
	level_spacers[level],
	table_idx_va, level_size);

	uintptr_t addr_inner = desc & TABLE_ADDR_MASK;

	xlat_tables_print_internal(ctx, table_idx_va,
	(uint64_t *)addr_inner,
	XLAT_TABLE_ENTRIES, level + 1U);
	} else {
	tf_printf("%sVA:0x%lx PA:0x%llx size:0x%zx ",
	level_spacers[level],
	table_idx_va,
	(uint64_t)(desc & TABLE_ADDR_MASK),
	level_size);
	xlat_desc_print(ctx, desc);
	tf_printf("\n");
	}
	}

	table_idx++;
	table_idx_va += level_size;
	}

	if (invalid_row_count > 1) {
	tf_printf(invalid_descriptors_ommited,
	level_spacers[level], invalid_row_count - 1);
	}
	}

	void xlat_tables_print(xlat_ctx_t *ctx)
	{
	const char *xlat_regime_str;
	int used_page_tables;

	if (ctx->xlat_regime == EL1_EL0_REGIME) {
	xlat_regime_str = "1&0";
	} else if (ctx->xlat_regime == EL2_REGIME) {
	xlat_regime_str = "2";
	} else {
	assert(ctx->xlat_regime == EL3_REGIME);
	xlat_regime_str = "3";
	}
	VERBOSE("Translation tables state:\n");
	VERBOSE(" Xlat regime: EL%s\n", xlat_regime_str);
	VERBOSE(" Max allowed PA: 0x%llx\n", ctx->pa_max_address);
	VERBOSE(" Max allowed VA: 0x%lx\n", ctx->va_max_address);
	VERBOSE(" Max mapped PA: 0x%llx\n", ctx->max_pa);
	VERBOSE(" Max mapped VA: 0x%lx\n", ctx->max_va);

	VERBOSE(" Initial lookup level: %u\n", ctx->base_level);
	VERBOSE(" Entries @initial lookup level: %u\n",
	ctx->base_table_entries);

	#if PLAT_XLAT_TABLES_DYNAMIC
	used_page_tables = 0;
	for (int i = 0; i < ctx->tables_num; ++i) {
	if (ctx->tables_mapped_regions[i] != 0)
	++used_page_tables;
	}
	#else
	used_page_tables = ctx->next_table;
	#endif
	VERBOSE(" Used %d sub-tables out of %d (spare: %d)\n",
	used_page_tables, ctx->tables_num,
	ctx->tables_num - used_page_tables);

	xlat_tables_print_internal(ctx, 0U, ctx->base_table,
	ctx->base_table_entries, ctx->base_level);
	}

	#endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */

	/*
	* Do a translation table walk to find the block or page descriptor that maps
	* virtual_addr.
	*
	* On success, return the address of the descriptor within the translation
	* table. Its lookup level is stored in '*out_level'.
	* On error, return NULL.
	*
	* xlat_table_base
	* Base address for the initial lookup level.
	* xlat_table_base_entries
	* Number of entries in the translation table for the initial lookup level.
	* virt_addr_space_size
	* Size in bytes of the virtual address space.
	*/
	static uint64_t *find_xlat_table_entry(uintptr_t virtual_addr,
	void *xlat_table_base,
	unsigned int xlat_table_base_entries,
	unsigned long long virt_addr_space_size,
	unsigned int *out_level)
	{
	unsigned int start_level;
	uint64_t *table;
	unsigned int entries;

	start_level = GET_XLAT_TABLE_LEVEL_BASE(virt_addr_space_size);

	table = xlat_table_base;
	entries = xlat_table_base_entries;

	for (unsigned int level = start_level;
	level <= XLAT_TABLE_LEVEL_MAX;
	++level) {
	uint64_t idx, desc, desc_type;

	idx = XLAT_TABLE_IDX(virtual_addr, level);
	if (idx >= entries) {
	WARN("Missing xlat table entry at address 0x%lx\n",
	virtual_addr);
	return NULL;
	}

	desc = table[idx];
	desc_type = desc & DESC_MASK;

	if (desc_type == INVALID_DESC) {
	VERBOSE("Invalid entry (memory not mapped)\n");
	return NULL;
	}

	if (level == XLAT_TABLE_LEVEL_MAX) {
	/*
	* Only page descriptors allowed at the final lookup
	* level.
	*/
	assert(desc_type == PAGE_DESC);
	*out_level = level;
	return &table[idx];
	}

	if (desc_type == BLOCK_DESC) {
	*out_level = level;
	return &table[idx];
	}

	assert(desc_type == TABLE_DESC);
	table = (uint64_t *)(uintptr_t)(desc & TABLE_ADDR_MASK);
	entries = XLAT_TABLE_ENTRIES;
	}

	/*
	* This shouldn't be reached, the translation table walk should end at
	* most at level XLAT_TABLE_LEVEL_MAX and return from inside the loop.
	*/
	assert(false);

	return NULL;
	}


	static int xlat_get_mem_attributes_internal(const xlat_ctx_t *ctx,
	uintptr_t base_va, uint32_t attributes, uint64_t *table_entry,
	unsigned long long addr_pa, unsigned int table_level)
	{
	uint64_t *entry;
	uint64_t desc;
	unsigned int level;
	unsigned long long virt_addr_space_size;

	/*
	* Sanity-check arguments.
	*/
	assert(ctx != NULL);
	assert(ctx->initialized);
	assert((ctx->xlat_regime == EL1_EL0_REGIME) \|\|
	(ctx->xlat_regime == EL2_REGIME) \|\|
	(ctx->xlat_regime == EL3_REGIME));

	virt_addr_space_size = (unsigned long long)ctx->va_max_address + 1ULL;
	assert(virt_addr_space_size > 0U);

	entry = find_xlat_table_entry(base_va,
	ctx->base_table,
	ctx->base_table_entries,
	virt_addr_space_size,
	&level);
	if (entry == NULL) {
	WARN("Address 0x%lx is not mapped.\n", base_va);
	return -EINVAL;
	}

	if (addr_pa != NULL) {
	addr_pa = entry & TABLE_ADDR_MASK;
	}

	if (table_entry != NULL) {
	*table_entry = entry;
	}

	if (table_level != NULL) {
	*table_level = level;
	}

	desc = *entry;

	#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
	VERBOSE("Attributes: ");
	xlat_desc_print(ctx, desc);
	tf_printf("\n");
	#endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */

	assert(attributes != NULL);
	*attributes = 0U;

	uint64_t attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;

	if (attr_index == ATTR_IWBWA_OWBWA_NTR_INDEX) {
	*attributes \|= MT_MEMORY;
	} else if (attr_index == ATTR_NON_CACHEABLE_INDEX) {
	*attributes \|= MT_NON_CACHEABLE;
	} else {
	assert(attr_index == ATTR_DEVICE_INDEX);
	*attributes \|= MT_DEVICE;
	}

	uint64_t ap2_bit = (desc >> AP2_SHIFT) & 1U;

	if (ap2_bit == AP2_RW)
	*attributes \|= MT_RW;

	if (ctx->xlat_regime == EL1_EL0_REGIME) {
	uint64_t ap1_bit = (desc >> AP1_SHIFT) & 1U;

	if (ap1_bit == AP1_ACCESS_UNPRIVILEGED)
	*attributes \|= MT_USER;
	}

	uint64_t ns_bit = (desc >> NS_SHIFT) & 1U;

	if (ns_bit == 1U)
	*attributes \|= MT_NS;

	uint64_t xn_mask = xlat_arch_regime_get_xn_desc(ctx->xlat_regime);

	if ((desc & xn_mask) == xn_mask) {
	*attributes \|= MT_EXECUTE_NEVER;
	} else {
	assert((desc & xn_mask) == 0U);
	}

	return 0;
	}


	int xlat_get_mem_attributes_ctx(const xlat_ctx_t *ctx, uintptr_t base_va,
	uint32_t *attr)
	{
	return xlat_get_mem_attributes_internal(ctx, base_va, attr,
	NULL, NULL, NULL);
	}


	int xlat_change_mem_attributes_ctx(const xlat_ctx_t *ctx, uintptr_t base_va,
	size_t size, uint32_t attr)
	{
	/* Note: This implementation isn't optimized. */

	assert(ctx != NULL);
	assert(ctx->initialized);

	unsigned long long virt_addr_space_size =
	(unsigned long long)ctx->va_max_address + 1U;
	assert(virt_addr_space_size > 0U);

	if (!IS_PAGE_ALIGNED(base_va)) {
	WARN("%s: Address 0x%lx is not aligned on a page boundary.\n",
	__func__, base_va);
	return -EINVAL;
	}

	if (size == 0U) {
	WARN("%s: Size is 0.\n", __func__);
	return -EINVAL;
	}

	if ((size % PAGE_SIZE) != 0U) {
	WARN("%s: Size 0x%zx is not a multiple of a page size.\n",
	__func__, size);
	return -EINVAL;
	}

	if (((attr & MT_EXECUTE_NEVER) == 0U) && ((attr & MT_RW) != 0U)) {
	WARN("%s: Mapping memory as read-write and executable not allowed.\n",
	__func__);
	return -EINVAL;
	}

	size_t pages_count = size / PAGE_SIZE;

	VERBOSE("Changing memory attributes of %zu pages starting from address 0x%lx...\n",
	pages_count, base_va);

	uintptr_t base_va_original = base_va;

	/*
	* Sanity checks.
	*/
	for (size_t i = 0U; i < pages_count; ++i) {
	const uint64_t *entry;
	uint64_t desc, attr_index;
	unsigned int level;

	entry = find_xlat_table_entry(base_va,
	ctx->base_table,
	ctx->base_table_entries,
	virt_addr_space_size,
	&level);
	if (entry == NULL) {
	WARN("Address 0x%lx is not mapped.\n", base_va);
	return -EINVAL;
	}

	desc = *entry;

	/*
	* Check that all the required pages are mapped at page
	* granularity.
	*/
	if (((desc & DESC_MASK) != PAGE_DESC) \|\|
	(level != XLAT_TABLE_LEVEL_MAX)) {
	WARN("Address 0x%lx is not mapped at the right granularity.\n",
	base_va);
	WARN("Granularity is 0x%llx, should be 0x%x.\n",
	(unsigned long long)XLAT_BLOCK_SIZE(level), PAGE_SIZE);
	return -EINVAL;
	}

	/*
	* If the region type is device, it shouldn't be executable.
	*/
	attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;
	if (attr_index == ATTR_DEVICE_INDEX) {
	if ((attr & MT_EXECUTE_NEVER) == 0U) {
	WARN("Setting device memory as executable at address 0x%lx.",
	base_va);
	return -EINVAL;
	}
	}

	base_va += PAGE_SIZE;
	}

	/* Restore original value. */
	base_va = base_va_original;

	for (unsigned int i = 0U; i < pages_count; ++i) {

	uint32_t old_attr = 0U, new_attr;
	uint64_t *entry = NULL;
	unsigned int level = 0U;
	unsigned long long addr_pa = 0ULL;

	(void) xlat_get_mem_attributes_internal(ctx, base_va, &old_attr,
	&entry, &addr_pa, &level);

	/*
	* From attr, only MT_RO/MT_RW, MT_EXECUTE/MT_EXECUTE_NEVER and
	* MT_USER/MT_PRIVILEGED are taken into account. Any other
	* information is ignored.
	*/

	/* Clean the old attributes so that they can be rebuilt. */
	new_attr = old_attr & ~(MT_RW \| MT_EXECUTE_NEVER \| MT_USER);

	/*
	* Update attributes, but filter out the ones this function
	* isn't allowed to change.
	*/
	new_attr \|= attr & (MT_RW \| MT_EXECUTE_NEVER \| MT_USER);

	/*
	* The break-before-make sequence requires writing an invalid
	* descriptor and making sure that the system sees the change
	* before writing the new descriptor.
	*/
	*entry = INVALID_DESC;
	#if !(HW_ASSISTED_COHERENCY \|\| WARMBOOT_ENABLE_DCACHE_EARLY)
	dccvac((uintptr_t)entry);
	#endif
	/* Invalidate any cached copy of this mapping in the TLBs. */
	xlat_arch_tlbi_va(base_va, ctx->xlat_regime);

	/* Ensure completion of the invalidation. */
	xlat_arch_tlbi_va_sync();

	/* Write new descriptor */
	*entry = xlat_desc(ctx, new_attr, addr_pa, level);
	#if !(HW_ASSISTED_COHERENCY \|\| WARMBOOT_ENABLE_DCACHE_EARLY)
	dccvac((uintptr_t)entry);
	#endif
	base_va += PAGE_SIZE;
	}

	/* Ensure that the last descriptor writen is seen by the system. */
	dsbish();

	return 0;
	}