xlat lib v2: Export translation context as an opaque type
At the moment, the translation context type (xlat_ctx_t) is a private
type reserved for the internal usage of the translation table library.
All exported APIs (implemented in xlat_tables_common.c) are wrappers
over the internal implementations that use such a translation context.
These wrappers unconditionally pass the current translation context
representing the memory mappings of the executing BL image. This means
that the caller has no control over which translation context the
library functions act on.
As a first step to make this code more flexible, this patch exports
the 'xlat_ctx_t' type. Note that, although the declaration of this type
is now public, its definition stays private. A macro is introduced to
statically allocate and initialize such a translation context.
The library now internally uses this macro to allocate the default
translation context for the running BL image.
Change-Id: Icece1cde4813fac19452c782b682c758142b1489
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
diff --git a/include/lib/xlat_tables/xlat_tables_v2_helpers.h b/include/lib/xlat_tables/xlat_tables_v2_helpers.h
new file mode 100644
index 0000000..f5e3100
--- /dev/null
+++ b/include/lib/xlat_tables/xlat_tables_v2_helpers.h
@@ -0,0 +1,151 @@
+/*
+ * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/*
+ * This header file contains internal definitions that are not supposed to be
+ * used outside of this library code.
+ */
+
+#ifndef __XLAT_TABLES_V2_HELPERS_H__
+#define __XLAT_TABLES_V2_HELPERS_H__
+
+#ifndef __XLAT_TABLES_V2_H__
+#error "Do not include this header file directly. Include xlat_tables_v2.h instead."
+#endif
+
+#ifndef __ASSEMBLY__
+
+#include <cassert.h>
+#include <platform_def.h>
+#include <stddef.h>
+#include <xlat_tables_arch.h>
+#include <xlat_tables_defs.h>
+
+/* Forward declaration */
+struct mmap_region;
+
+/* Struct that holds all information about the translation tables. */
+struct xlat_ctx {
+ /*
+ * Max allowed Virtual and Physical Addresses.
+ */
+ unsigned long long pa_max_address;
+ uintptr_t va_max_address;
+
+ /*
+ * Array of all memory regions stored in order of ascending end address
+ * and ascending size to simplify the code that allows overlapping
+ * regions. The list is terminated by the first entry with size == 0.
+ * The max size of the list is stored in `mmap_num`. `mmap` points to an
+ * array of mmap_num + 1 elements, so that there is space for the final
+ * null entry.
+ */
+ struct mmap_region *mmap;
+ unsigned int mmap_num;
+
+ /*
+ * Array of finer-grain translation tables.
+ * For example, if the initial lookup level is 1 then this array would
+ * contain both level-2 and level-3 entries.
+ */
+ uint64_t (*tables)[XLAT_TABLE_ENTRIES];
+ unsigned int tables_num;
+ /*
+ * Keep track of how many regions are mapped in each table. The base
+ * table can't be unmapped so it isn't needed to keep track of it.
+ */
+#if PLAT_XLAT_TABLES_DYNAMIC
+ int *tables_mapped_regions;
+#endif /* PLAT_XLAT_TABLES_DYNAMIC */
+
+ unsigned int next_table;
+
+ /*
+ * Base translation table. It doesn't need to have the same amount of
+ * entries as the ones used for other levels.
+ */
+ uint64_t *base_table;
+ unsigned int base_table_entries;
+
+ /*
+ * Max Physical and Virtual addresses currently in use by the
+ * translation tables. These might get updated as we map/unmap memory
+ * regions but they will never go beyond pa/va_max_address.
+ */
+ unsigned long long max_pa;
+ uintptr_t max_va;
+
+ /* Level of the base translation table. */
+ unsigned int base_level;
+
+ /* Set to 1 when the translation tables are initialized. */
+ unsigned int initialized;
+
+ /*
+ * Bit mask that has to be ORed to the rest of a translation table
+ * descriptor in order to prohibit execution of code at the exception
+ * level of this translation context.
+ */
+ uint64_t execute_never_mask;
+};
+
+#if PLAT_XLAT_TABLES_DYNAMIC
+#define _ALLOC_DYNMAP_STRUCT(_ctx_name, _xlat_tables_count) \
+ static int _ctx_name##_mapped_regions[_xlat_tables_count];
+
+#define _REGISTER_DYNMAP_STRUCT(_ctx_name) \
+ .tables_mapped_regions = _ctx_name##_mapped_regions,
+#else
+#define _ALLOC_DYNMAP_STRUCT(_ctx_name, _xlat_tables_count) \
+ /* do nothing */
+
+#define _REGISTER_DYNMAP_STRUCT(_ctx_name) \
+ /* do nothing */
+#endif /* PLAT_XLAT_TABLES_DYNAMIC */
+
+
+#define _REGISTER_XLAT_CONTEXT(_ctx_name, _mmap_count, _xlat_tables_count, \
+ _virt_addr_space_size, _phy_addr_space_size) \
+ CASSERT(CHECK_VIRT_ADDR_SPACE_SIZE(_virt_addr_space_size), \
+ assert_invalid_virtual_addr_space_size_for_##_ctx_name); \
+ \
+ CASSERT(CHECK_PHY_ADDR_SPACE_SIZE(_phy_addr_space_size), \
+ assert_invalid_physical_addr_space_sizefor_##_ctx_name); \
+ \
+ static mmap_region_t _ctx_name##_mmap[_mmap_count + 1]; \
+ \
+ static uint64_t _ctx_name##_xlat_tables[_xlat_tables_count] \
+ [XLAT_TABLE_ENTRIES] \
+ __aligned(XLAT_TABLE_SIZE) __section("xlat_table"); \
+ \
+ static uint64_t _ctx_name##_base_xlat_table \
+ [GET_NUM_BASE_LEVEL_ENTRIES(_virt_addr_space_size)] \
+ __aligned(GET_NUM_BASE_LEVEL_ENTRIES(_virt_addr_space_size) \
+ * sizeof(uint64_t)); \
+ \
+ _ALLOC_DYNMAP_STRUCT(_ctx_name, _xlat_tables_count) \
+ \
+ static xlat_ctx_t _ctx_name##_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, \
+ .base_level = GET_XLAT_TABLE_LEVEL_BASE(_virt_addr_space_size), \
+ .base_table = _ctx_name##_base_xlat_table, \
+ .base_table_entries = \
+ GET_NUM_BASE_LEVEL_ENTRIES(_virt_addr_space_size), \
+ .tables = _ctx_name##_xlat_tables, \
+ .tables_num = _xlat_tables_count, \
+ _REGISTER_DYNMAP_STRUCT(_ctx_name) \
+ .max_pa = 0, \
+ .max_va = 0, \
+ .next_table = 0, \
+ .initialized = 0, \
+ }
+
+#endif /*__ASSEMBLY__*/
+
+#endif /* __XLAT_TABLES_V2_HELPERS_H__ */