xlat v2: Split code into separate files

Instead of having one big file with all the code, it's better to have
a few smaller files that are more manageable:

- xlat_tables_core.c: Code related to the core functionality of the
  library (map and unmap regions, initialize xlat context).
- xlat_tables_context.c: Instantiation of the active image context
  as well as APIs to manipulate it.
- xlat_tables_utils.c: Helper code that isn't part of the core
  functionality (change attributes, debug print messages).

Change-Id: I3ea956fc1afd7473c0bb5e7c6aab3b2e5d88c711
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>

include/lib/xlat_tables/xlat_tables_v2.h

@@ -123,10 +123,8 @@ typedef struct mmap_region {
 /*
  * Translation regimes supported by this library.
  */
-typedef enum xlat_regime {
-	EL1_EL0_REGIME,
-	EL3_REGIME,
-} xlat_regime_t;
+#define EL1_EL0_REGIME		1
+#define EL3_REGIME		3
 
 /*
  * Declare the translation context type.
@@ -163,10 +161,10 @@ typedef struct xlat_ctx xlat_ctx_t;
  */
 #define REGISTER_XLAT_CONTEXT(_ctx_name, _mmap_count, _xlat_tables_count, \
 			_virt_addr_space_size, _phy_addr_space_size)	\
-	_REGISTER_XLAT_CONTEXT_FULL_SPEC(_ctx_name, _mmap_count,	\
-					 _xlat_tables_count,		\
-					 _virt_addr_space_size,		\
-					 _phy_addr_space_size,		\
+	_REGISTER_XLAT_CONTEXT_FULL_SPEC(_ctx_name, (_mmap_count),	\
+					 (_xlat_tables_count),		\
+					 (_virt_addr_space_size),	\
+					 (_phy_addr_space_size),	\
 					 IMAGE_XLAT_DEFAULT_REGIME,	\
 					"xlat_table")
 
@@ -175,7 +173,7 @@ typedef struct xlat_ctx xlat_ctx_t;
  *
  * _xlat_regime:
  *   Specify the translation regime managed by this xlat_ctx_t instance. The
- *   values are the one from xlat_regime_t enumeration.
+ *   values are the one from the EL*_REGIME definitions.
  *
  * _section_name:
  *   Specify the name of the section where the translation tables have to be
@@ -184,11 +182,11 @@ typedef struct xlat_ctx xlat_ctx_t;
 #define REGISTER_XLAT_CONTEXT2(_ctx_name, _mmap_count, _xlat_tables_count, \
 			_virt_addr_space_size, _phy_addr_space_size,	\
 			_xlat_regime, _section_name)			\
-	_REGISTER_XLAT_CONTEXT_FULL_SPEC(_ctx_name, _mmap_count,	\
-					 _xlat_tables_count,		\
-					 _virt_addr_space_size,		\
-					 _phy_addr_space_size,		\
-					 _xlat_regime, _section_name)
+	_REGISTER_XLAT_CONTEXT_FULL_SPEC(_ctx_name, (_mmap_count),	\
+					 (_xlat_tables_count),		\
+					 (_virt_addr_space_size),	\
+					 (_phy_addr_space_size),	\
+					 (_xlat_regime), (_section_name))
 
 /******************************************************************************
  * Generic translation table APIs.

include/lib/xlat_tables/xlat_tables_v2_helpers.h

@@ -109,10 +109,8 @@ struct xlat_ctx {
 	unsigned int initialized;
 
 	/*
-	 * Translation regime managed by this xlat_ctx_t. It takes the values of
-	 * the enumeration xlat_regime_t. The type is "int" to avoid a circular
-	 * dependency on xlat_tables_v2.h, but this member must be treated as
-	 * xlat_regime_t.
+	 * Translation regime managed by this xlat_ctx_t. It should be one of
+	 * the EL*_REGIME defines.
 	 */
 	int xlat_regime;
 };
@@ -157,7 +155,7 @@ struct xlat_ctx {
 		.va_max_address = (_virt_addr_space_size) - 1,			\
 		.pa_max_address = (_phy_addr_space_size) - 1,			\
 		.mmap = _ctx_name##_mmap,					\
-		.mmap_num = _mmap_count,					\
+		.mmap_num = (_mmap_count),					\
 		.base_level = GET_XLAT_TABLE_LEVEL_BASE(_virt_addr_space_size),	\
 		.base_table = _ctx_name##_base_xlat_table,			\
 		.base_table_entries =						\

lib/xlat_tables_v2/aarch32/xlat_tables_arch.c

@@ -61,7 +61,7 @@ void xlat_arch_tlbi_va(uintptr_t va)
 	tlbimvaais(TLBI_ADDR(va));
 }
 
-void xlat_arch_tlbi_va_regime(uintptr_t va, xlat_regime_t xlat_regime __unused)
+void xlat_arch_tlbi_va_regime(uintptr_t va, int xlat_regime __unused)
 {
 	/*
 	 * Ensure the translation table write has drained into memory before

lib/xlat_tables_v2/aarch32/xlat_tables_arch_private.h

@@ -14,7 +14,7 @@
  * Return the execute-never mask that will prevent instruction fetch at the
  * given translation regime.
  */
-static inline uint64_t xlat_arch_regime_get_xn_desc(xlat_regime_t regime __unused)
+static inline uint64_t xlat_arch_regime_get_xn_desc(int regime __unused)
 {
 	return UPPER_ATTRS(XN);
 }

lib/xlat_tables_v2/aarch64/xlat_tables_arch.c

@@ -7,11 +7,8 @@
 #include <arch.h>
 #include <arch_helpers.h>
 #include <assert.h>
-#include <bl_common.h>
 #include <cassert.h>
-#include <common_def.h>
 #include <sys/types.h>
-#include <utils.h>
 #include <utils_def.h>
 #include <xlat_tables_v2.h>
 #include "../xlat_tables_private.h"
@@ -128,7 +125,7 @@ void xlat_arch_tlbi_va(uintptr_t va)
 #endif
 }
 
-void xlat_arch_tlbi_va_regime(uintptr_t va, xlat_regime_t xlat_regime)
+void xlat_arch_tlbi_va_regime(uintptr_t va, int xlat_regime)
 {
 	/*
 	 * Ensure the translation table write has drained into memory before

lib/xlat_tables_v2/aarch64/xlat_tables_arch_private.h

@@ -15,7 +15,7 @@
  * Return the execute-never mask that will prevent instruction fetch at all ELs
  * that are part of the given translation regime.
  */
-static inline uint64_t xlat_arch_regime_get_xn_desc(xlat_regime_t regime)
+static inline uint64_t xlat_arch_regime_get_xn_desc(int regime)
 {
 	if (regime == EL1_EL0_REGIME) {
 		return UPPER_ATTRS(UXN) | UPPER_ATTRS(PXN);

lib/xlat_tables_v2/xlat_tables.mk

@@ -7,6 +7,8 @@
 XLAT_TABLES_LIB_SRCS	:=	$(addprefix lib/xlat_tables_v2/,	\
 				${ARCH}/enable_mmu.S			\
 				${ARCH}/xlat_tables_arch.c		\
-				xlat_tables_internal.c)
+				xlat_tables_context.c			\
+				xlat_tables_core.c			\
+				xlat_tables_utils.c)
 
 INCLUDES		+=	-Ilib/xlat_tables_v2/${ARCH}

lib/xlat_tables_v2/xlat_tables_context.c

+/*
+ * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <debug.h>
+#include <platform_def.h>
+#include <xlat_tables_defs.h>
+#include <xlat_tables_v2.h>
+
+#include "xlat_tables_private.h"
+
+/*
+ * Each platform can define the size of its physical and virtual address spaces.
+ * If the platform hasn't defined one or both of them, default to
+ * ADDR_SPACE_SIZE. The latter is deprecated, though.
+ */
+#if ERROR_DEPRECATED
+# ifdef ADDR_SPACE_SIZE
+#  error "ADDR_SPACE_SIZE is deprecated. Use PLAT_xxx_ADDR_SPACE_SIZE instead."
+# endif
+#elif defined(ADDR_SPACE_SIZE)
+# ifndef PLAT_PHY_ADDR_SPACE_SIZE
+#  define PLAT_PHY_ADDR_SPACE_SIZE	ADDR_SPACE_SIZE
+# endif
+# ifndef PLAT_VIRT_ADDR_SPACE_SIZE
+#  define PLAT_VIRT_ADDR_SPACE_SIZE	ADDR_SPACE_SIZE
+# endif
+#endif
+
+/*
+ * Allocate and initialise the default translation context for the BL image
+ * currently executing.
+ */
+REGISTER_XLAT_CONTEXT(tf, MAX_MMAP_REGIONS, MAX_XLAT_TABLES,
+		PLAT_VIRT_ADDR_SPACE_SIZE, PLAT_PHY_ADDR_SPACE_SIZE);
+
+void mmap_add_region(unsigned long long base_pa, uintptr_t base_va, size_t size,
+		     unsigned int attr)
+{
+	mmap_region_t mm = MAP_REGION(base_pa, base_va, size, attr);
+
+	mmap_add_region_ctx(&tf_xlat_ctx, &mm);
+}
+
+void mmap_add(const mmap_region_t *mm)
+{
+	mmap_add_ctx(&tf_xlat_ctx, mm);
+}
+
+#if PLAT_XLAT_TABLES_DYNAMIC
+
+int mmap_add_dynamic_region(unsigned long long base_pa, uintptr_t base_va,
+			    size_t size, unsigned int attr)
+{
+	mmap_region_t mm = MAP_REGION(base_pa, base_va, size, attr);
+
+	return mmap_add_dynamic_region_ctx(&tf_xlat_ctx, &mm);
+}
+
+int mmap_remove_dynamic_region(uintptr_t base_va, size_t size)
+{
+	return mmap_remove_dynamic_region_ctx(&tf_xlat_ctx,
+					base_va, size);
+}
+
+#endif /* PLAT_XLAT_TABLES_DYNAMIC */
+
+void init_xlat_tables(void)
+{
+	init_xlat_tables_ctx(&tf_xlat_ctx);
+}
+
+/*
+ * If dynamic allocation of new regions is disabled then by the time we call the
+ * function enabling the MMU, we'll have registered all the memory regions to
+ * map for the system's lifetime. Therefore, at this point we know the maximum
+ * physical address that will ever be mapped.
+ *
+ * If dynamic allocation is enabled then we can't make any such assumption
+ * because the maximum physical address could get pushed while adding a new
+ * region. Therefore, in this case we have to assume that the whole address
+ * space size might be mapped.
+ */
+#ifdef PLAT_XLAT_TABLES_DYNAMIC
+#define MAX_PHYS_ADDR	tf_xlat_ctx.pa_max_address
+#else
+#define MAX_PHYS_ADDR	tf_xlat_ctx.max_pa
+#endif
+
+#ifdef AARCH32
+
+void enable_mmu_secure(unsigned int flags)
+{
+	setup_mmu_cfg(flags, tf_xlat_ctx.base_table, MAX_PHYS_ADDR,
+			tf_xlat_ctx.va_max_address);
+	enable_mmu_direct(flags);
+}
+
+#else
+
+void enable_mmu_el1(unsigned int flags)
+{
+	setup_mmu_cfg(flags, tf_xlat_ctx.base_table, MAX_PHYS_ADDR,
+			tf_xlat_ctx.va_max_address);
+	enable_mmu_direct_el1(flags);
+}
+
+void enable_mmu_el3(unsigned int flags)
+{
+	setup_mmu_cfg(flags, tf_xlat_ctx.base_table, MAX_PHYS_ADDR,
+			tf_xlat_ctx.va_max_address);
+	enable_mmu_direct_el3(flags);
+}
+
+#endif /* AARCH32 */

lib/xlat_tables_v2/xlat_tables_private.h

@@ -50,7 +50,7 @@
  * S-EL1.
  */
 void xlat_arch_tlbi_va(uintptr_t va);
-void xlat_arch_tlbi_va_regime(uintptr_t va, xlat_regime_t xlat_regime);
+void xlat_arch_tlbi_va_regime(uintptr_t va, int xlat_regime);
 
 /*
  * This function has to be called at the end of any code that uses the function
@@ -59,7 +59,7 @@ void xlat_arch_tlbi_va_regime(uintptr_t va, xlat_regime_t xlat_regime);
 void xlat_arch_tlbi_va_sync(void);
 
 /* Print VA, PA, size and attributes of all regions in the mmap array. */
-void print_mmap(mmap_region_t *const mmap);
+void xlat_mmap_print(mmap_region_t *const mmap);
 
 /*
  * Print the current state of the translation tables by reading them from
@@ -67,6 +67,12 @@ void print_mmap(mmap_region_t *const mmap);
  */
 void xlat_tables_print(xlat_ctx_t *ctx);
 
+/*
+ * Returns a block/page table descriptor for the given level and attributes.
+ */
+uint64_t xlat_desc(const xlat_ctx_t *ctx, uint32_t attr,
+		   unsigned long long addr_pa, int level);
+
 /*
  * Architecture-specific initialization code.
  */

lib/xlat_tables_v2/xlat_tables_utils.c

+/*
+ * 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 <types.h>
+#include <utils_def.h>
+#include <xlat_tables_arch_private.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 mmap_region_t *const mmap)
+{
+	/* Empty */
+}
+
+void xlat_tables_print(__unused xlat_ctx_t *ctx)
+{
+	/* Empty */
+}
+
+#else /* if LOG_LEVEL >= LOG_LEVEL_VERBOSE */
+
+void xlat_mmap_print(mmap_region_t *const 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)
+{
+	int 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");
+	}
+
+	const char *priv_str = "(PRIV)";
+	const char *user_str = "(USER)";
+
+	/*
+	 * Showing Privileged vs Unprivileged only makes sense for EL1&0
+	 * mappings
+	 */
+	const char *ro_str = "-RO";
+	const char *rw_str = "-RW";
+	const char *no_access_str = "-NOACCESS";
+
+	if (xlat_regime == EL3_REGIME) {
+		/* For EL3, the AP[2] bit is all what matters */
+		tf_printf("%s", (desc & LOWER_ATTRS(AP_RO)) ? ro_str : rw_str);
+	} else {
+		const char *ap_str = (desc & LOWER_ATTRS(AP_RO)) ? ro_str : rw_str;
+		tf_printf("%s", ap_str);
+		tf_printf("%s", priv_str);
+		/*
+		 * EL0 can only have the same permissions as EL1 or no
+		 * permissions at all.
+		 */
+		tf_printf("%s",
+			  (desc & LOWER_ATTRS(AP_ACCESS_UNPRIVILEGED))
+			  ? ap_str : no_access_str);
+		tf_printf("%s", user_str);
+	}
+
+	const char *xn_str = "-XN";
+	const char *exec_str = "-EXEC";
+
+	if (xlat_regime == EL3_REGIME) {
+		/* For EL3, the XN bit is all what matters */
+		tf_printf("%s", (UPPER_ATTRS(XN) & desc) ? xn_str : exec_str);
+	} else {
+		/* For EL0 and EL1, we need to know who has which rights */
+		tf_printf("%s", (UPPER_ATTRS(PXN) & desc) ? xn_str : exec_str);
+		tf_printf("%s", priv_str);
+
+		tf_printf("%s", (UPPER_ATTRS(UXN) & desc) ? xn_str : exec_str);
+		tf_printf("%s", user_str);
+	}
+
+	tf_printf(LOWER_ATTRS(NS) & desc ? "-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,
+		const uintptr_t table_base_va,
+		uint64_t *const table_base, const int table_entries,
+		const unsigned int level)
+{
+	assert(level <= XLAT_TABLE_LEVEL_MAX);
+
+	uint64_t desc;
+	uintptr_t table_idx_va = table_base_va;
+	int table_idx = 0;
+
+	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:%p size:0x%zx\n",
+					  level_spacers[level],
+					  (void *)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:%p size:0x%zx\n",
+					  level_spacers[level],
+					  (void *)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 + 1);
+			} else {
+				tf_printf("%sVA:%p PA:0x%llx size:0x%zx ",
+					  level_spacers[level],
+					  (void *)table_idx_va,
+					  (unsigned long long)(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;
+	if (ctx->xlat_regime == EL1_EL0_REGIME) {
+		xlat_regime_str = "1&0";
+	} 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:  %p\n", (void *) ctx->va_max_address);
+	VERBOSE("  Max mapped PA:   0x%llx\n", ctx->max_pa);
+	VERBOSE("  Max mapped VA:   %p\n", (void *) ctx->max_va);
+
+	VERBOSE("  Initial lookup level: %i\n", ctx->base_level);
+	VERBOSE("  Entries @initial lookup level: %i\n",
+		ctx->base_table_entries);
+
+	int used_page_tables;
+#if PLAT_XLAT_TABLES_DYNAMIC
+	used_page_tables = 0;
+	for (unsigned 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 %i sub-tables out of %i (spare: %i)\n",
+		used_page_tables, ctx->tables_num,
+		ctx->tables_num - used_page_tables);
+
+	xlat_tables_print_internal(ctx, 0, 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,
+				       int xlat_table_base_entries,
+				       unsigned long long virt_addr_space_size,
+				       int *out_level)
+{
+	unsigned int start_level;
+	uint64_t *table;
+	int entries;
+
+	VERBOSE("%s(%p)\n", __func__, (void *)virtual_addr);
+
+	start_level = GET_XLAT_TABLE_LEVEL_BASE(virt_addr_space_size);
+	VERBOSE("Starting translation table walk from level %i\n", start_level);
+
+	table = xlat_table_base;
+	entries = xlat_table_base_entries;
+
+	for (unsigned int level = start_level;
+	     level <= XLAT_TABLE_LEVEL_MAX;
+	     ++level) {
+		int idx;
+		uint64_t desc;
+		uint64_t desc_type;
+
+		VERBOSE("Table address: %p\n", (void *)table);
+
+		idx = XLAT_TABLE_IDX(virtual_addr, level);
+		VERBOSE("Index into level %i table: %i\n", level, idx);
+		if (idx >= entries) {
+			VERBOSE("Invalid address\n");
+			return NULL;
+		}
+
+		desc = table[idx];
+		desc_type = desc & DESC_MASK;
+		VERBOSE("Descriptor at level %i: 0x%llx\n", level,
+				(unsigned long long)desc);
+
+		if (desc_type == INVALID_DESC) {
+			VERBOSE("Invalid entry (memory not mapped)\n");
+			return NULL;
+		}
+
+		if (level == XLAT_TABLE_LEVEL_MAX) {
+			/*
+			 * There can't be table entries at the final lookup
+			 * level.
+			 */
+			assert(desc_type == PAGE_DESC);
+			VERBOSE("Descriptor mapping a memory page (size: 0x%llx)\n",
+				(unsigned long long)XLAT_BLOCK_SIZE(XLAT_TABLE_LEVEL_MAX));
+			*out_level = level;
+			return &table[idx];
+		}
+
+		if (desc_type == BLOCK_DESC) {
+			VERBOSE("Descriptor mapping a memory block (size: 0x%llx)\n",
+				(unsigned long long)XLAT_BLOCK_SIZE(level));
+			*out_level = level;
+			return &table[idx];
+		}
+
+		assert(desc_type == TABLE_DESC);
+		VERBOSE("Table descriptor, continuing xlat table walk...\n");
+		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(0);
+
+	return NULL;
+}
+
+
+static int 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, int *table_level)
+{
+	uint64_t *entry;
+	uint64_t desc;
+	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 == EL3_REGIME);
+
+	virt_addr_space_size = (unsigned long long)ctx->va_max_address + 1;
+	assert(virt_addr_space_size > 0);
+
+	entry = find_xlat_table_entry(base_va,
+				ctx->base_table,
+				ctx->base_table_entries,
+				virt_addr_space_size,
+				&level);
+	if (entry == NULL) {
+		WARN("Address %p is not mapped.\n", (void *)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 = 0;
+
+	int 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;
+	}
+
+	int ap2_bit = (desc >> AP2_SHIFT) & 1;
+
+	if (ap2_bit == AP2_RW)
+		*attributes |= MT_RW;
+
+	if (ctx->xlat_regime == EL1_EL0_REGIME) {
+		int ap1_bit = (desc >> AP1_SHIFT) & 1;
+		if (ap1_bit == AP1_ACCESS_UNPRIVILEGED)
+			*attributes |= MT_USER;
+	}
+
+	int ns_bit = (desc >> NS_SHIFT) & 1;
+
+	if (ns_bit == 1)
+		*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) == 0);
+	}
+
+	return 0;
+}
+
+
+int get_mem_attributes(const xlat_ctx_t *ctx, uintptr_t base_va,
+		       uint32_t *attributes)
+{
+	return get_mem_attributes_internal(ctx, base_va, attributes,
+					   NULL, NULL, NULL);
+}
+
+
+int change_mem_attributes(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 + 1;
+	assert(virt_addr_space_size > 0);
+
+	if (!IS_PAGE_ALIGNED(base_va)) {
+		WARN("%s: Address %p is not aligned on a page boundary.\n",
+		     __func__, (void *)base_va);
+		return -EINVAL;
+	}
+
+	if (size == 0) {
+		WARN("%s: Size is 0.\n", __func__);
+		return -EINVAL;
+	}
+
+	if ((size % PAGE_SIZE) != 0) {
+		WARN("%s: Size 0x%zx is not a multiple of a page size.\n",
+		     __func__, size);
+		return -EINVAL;
+	}
+
+	if (((attr & MT_EXECUTE_NEVER) == 0) && ((attr & MT_RW) != 0)) {
+		WARN("%s() doesn't allow to remap memory as read-write and executable.\n",
+		     __func__);
+		return -EINVAL;
+	}
+
+	int pages_count = size / PAGE_SIZE;
+
+	VERBOSE("Changing memory attributes of %i pages starting from address %p...\n",
+		pages_count, (void *)base_va);
+
+	uintptr_t base_va_original = base_va;
+
+	/*
+	 * Sanity checks.
+	 */
+	for (int i = 0; i < pages_count; ++i) {
+		uint64_t *entry;
+		uint64_t desc;
+		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 %p is not mapped.\n", (void *)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 %p is not mapped at the right granularity.\n",
+			     (void *)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.
+		 */
+		int attr_index = (desc >> ATTR_INDEX_SHIFT) & ATTR_INDEX_MASK;
+		if (attr_index == ATTR_DEVICE_INDEX) {
+			if ((attr & MT_EXECUTE_NEVER) == 0) {
+				WARN("Setting device memory as executable at address %p.",
+				     (void *)base_va);
+				return -EINVAL;
+			}
+		}
+
+		base_va += PAGE_SIZE;
+	}
+
+	/* Restore original value. */
+	base_va = base_va_original;
+
+	VERBOSE("%s: All pages are mapped, now changing their attributes...\n",
+		__func__);
+
+	for (int i = 0; i < pages_count; ++i) {
+
+		uint32_t old_attr, new_attr;
+		uint64_t *entry;
+		int level;
+		unsigned long long addr_pa;
+
+		get_mem_attributes_internal(ctx, base_va, &old_attr,
+					    &entry, &addr_pa, &level);
+
+		VERBOSE("Old attributes: 0x%x\n", old_attr);
+
+		/*
+		 * 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);
+
+		VERBOSE("New attributes: 0x%x\n", new_attr);
+
+		/*
+		 * 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;
+
+		/* Invalidate any cached copy of this mapping in the TLBs. */
+		xlat_arch_tlbi_va_regime(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);
+
+		base_va += PAGE_SIZE;
+	}
+
+	/* Ensure that the last descriptor writen is seen by the system. */
+	dsbish();
+
+	return 0;
+}