Add version 2 of xlat tables library
The folder lib/xlat_tables_v2 has been created to store a new version
of the translation tables library for further modifications in patches
to follow. At the moment it only contains a basic implementation that
supports static regions.
This library allows different translation tables to be modified by
using different 'contexts'. For now, the implementation defaults to
the translation tables used by the current image, but it is possible
to modify other tables than the ones in use.
Added a new API to print debug information for the current state of
the translation tables, rather than printing the information while
the tables are being created. This allows subsequent debug printing
of the xlat tables after they have been changed, which will be useful
when dynamic regions are implemented in a patch to follow.
The common definitions stored in `xlat_tables.h` header have been moved
to a new file common to both versions, `xlat_tables_defs.h`.
All headers related to the translation tables library have been moved to
a the subfolder `xlat_tables`.
Change-Id: Ia55962c33e0b781831d43a548e505206dffc5ea9
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/lib/xlat_tables_v2/xlat_tables_internal.c b/lib/xlat_tables_v2/xlat_tables_internal.c
new file mode 100644
index 0000000..9d4c837
--- /dev/null
+++ b/lib/xlat_tables_v2/xlat_tables_internal.c
@@ -0,0 +1,667 @@
+/*
+ * Copyright (c) 2017, 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 <cassert.h>
+#include <common_def.h>
+#include <debug.h>
+#include <errno.h>
+#include <platform_def.h>
+#include <string.h>
+#include <types.h>
+#include <utils.h>
+#include <xlat_tables_v2.h>
+#ifdef AARCH32
+# include "aarch32/xlat_tables_arch.h"
+#else
+# include "aarch64/xlat_tables_arch.h"
+#endif
+#include "xlat_tables_private.h"
+
+/* Returns a pointer to the first empty translation table. */
+static uint64_t *xlat_table_get_empty(xlat_ctx_t *ctx)
+{
+ assert(ctx->next_table < ctx->tables_num);
+
+ return ctx->tables[ctx->next_table++];
+}
+
+/* Returns a block/page table descriptor for the given level and attributes. */
+static uint64_t xlat_desc(unsigned int attr, unsigned long long addr_pa,
+ int level)
+{
+ uint64_t desc;
+ int mem_type;
+
+ /* Make sure that the granularity is fine enough to map this address. */
+ assert((addr_pa & XLAT_BLOCK_MASK(level)) == 0);
+
+ desc = addr_pa;
+ /*
+ * There are different translation table descriptors for level 3 and the
+ * rest.
+ */
+ desc |= (level == XLAT_TABLE_LEVEL_MAX) ? PAGE_DESC : BLOCK_DESC;
+ /*
+ * Always set the access flag, as TF doesn't manage access flag faults.
+ * Deduce other fields of the descriptor based on the MT_NS and MT_RW
+ * memory region attributes.
+ */
+ desc |= (attr & MT_NS) ? LOWER_ATTRS(NS) : 0;
+ desc |= (attr & MT_RW) ? LOWER_ATTRS(AP_RW) : LOWER_ATTRS(AP_RO);
+ desc |= LOWER_ATTRS(ACCESS_FLAG);
+
+ /*
+ * Deduce shareability domain and executability of the memory region
+ * from the memory type of the attributes (MT_TYPE).
+ *
+ * Data accesses to device memory and non-cacheable normal memory are
+ * coherent for all observers in the system, and correspondingly are
+ * always treated as being Outer Shareable. Therefore, for these 2 types
+ * of memory, it is not strictly needed to set the shareability field
+ * in the translation tables.
+ */
+ mem_type = MT_TYPE(attr);
+ if (mem_type == MT_DEVICE) {
+ desc |= LOWER_ATTRS(ATTR_DEVICE_INDEX | OSH);
+ /*
+ * Always map device memory as execute-never.
+ * This is to avoid the possibility of a speculative instruction
+ * fetch, which could be an issue if this memory region
+ * corresponds to a read-sensitive peripheral.
+ */
+ desc |= UPPER_ATTRS(XN);
+ } else { /* Normal memory */
+ /*
+ * Always map read-write normal memory as execute-never.
+ * (Trusted Firmware doesn't self-modify its code, therefore
+ * R/W memory is reserved for data storage, which must not be
+ * executable.)
+ * Note that setting the XN bit here is for consistency only.
+ * The enable_mmu_elx() function sets the SCTLR_EL3.WXN bit,
+ * which makes any writable memory region to be treated as
+ * execute-never, regardless of the value of the XN bit in the
+ * translation table.
+ *
+ * For read-only memory, rely on the MT_EXECUTE/MT_EXECUTE_NEVER
+ * attribute to figure out the value of the XN bit.
+ */
+ if ((attr & MT_RW) || (attr & MT_EXECUTE_NEVER))
+ desc |= UPPER_ATTRS(XN);
+
+ if (mem_type == MT_MEMORY) {
+ desc |= LOWER_ATTRS(ATTR_IWBWA_OWBWA_NTR_INDEX | ISH);
+ } else {
+ assert(mem_type == MT_NON_CACHEABLE);
+ desc |= LOWER_ATTRS(ATTR_NON_CACHEABLE_INDEX | OSH);
+ }
+ }
+
+ return desc;
+}
+
+/*
+ * Enumeration of actions that can be made when mapping table entries depending
+ * on the previous value in that entry and information about the region being
+ * mapped.
+ */
+typedef enum {
+
+ /* Do nothing */
+ ACTION_NONE,
+
+ /* Write a block (or page, if in level 3) entry. */
+ ACTION_WRITE_BLOCK_ENTRY,
+
+ /*
+ * Create a new table and write a table entry pointing to it. Recurse
+ * into it for further processing.
+ */
+ ACTION_CREATE_NEW_TABLE,
+
+ /*
+ * There is a table descriptor in this entry, read it and recurse into
+ * that table for further processing.
+ */
+ ACTION_RECURSE_INTO_TABLE,
+
+} action_t;
+
+/*
+ * From the given arguments, it decides which action to take when mapping the
+ * specified region.
+ */
+static action_t xlat_tables_map_region_action(const mmap_region_t *mm,
+ const int desc_type, const unsigned long long dest_pa,
+ const uintptr_t table_entry_base_va, const int level)
+{
+ uintptr_t mm_end_va = mm->base_va + mm->size - 1;
+ uintptr_t table_entry_end_va =
+ table_entry_base_va + XLAT_BLOCK_SIZE(level) - 1;
+
+ /*
+ * The descriptor types allowed depend on the current table level.
+ */
+
+ if ((mm->base_va <= table_entry_base_va) &&
+ (mm_end_va >= table_entry_end_va)) {
+
+ /*
+ * Table entry is covered by region
+ * --------------------------------
+ *
+ * This means that this table entry can describe the whole
+ * translation with this granularity in principle.
+ */
+
+ if (level == 3) {
+ /*
+ * Last level, only page descriptors are allowed.
+ */
+ if (desc_type == PAGE_DESC) {
+ /*
+ * There's another region mapped here, don't
+ * overwrite.
+ */
+ return ACTION_NONE;
+ } else {
+ assert(desc_type == INVALID_DESC);
+ return ACTION_WRITE_BLOCK_ENTRY;
+ }
+
+ } else {
+
+ /*
+ * Other levels. Table descriptors are allowed. Block
+ * descriptors too, but they have some limitations.
+ */
+
+ if (desc_type == TABLE_DESC) {
+ /* There's already a table, recurse into it. */
+ return ACTION_RECURSE_INTO_TABLE;
+
+ } else if (desc_type == INVALID_DESC) {
+ /*
+ * There's nothing mapped here, create a new
+ * entry.
+ *
+ * Check if the destination granularity allows
+ * us to use a block descriptor or we need a
+ * finer table for it.
+ *
+ * Also, check if the current level allows block
+ * descriptors. If not, create a table instead.
+ */
+ if ((dest_pa & XLAT_BLOCK_MASK(level)) ||
+ (level < MIN_LVL_BLOCK_DESC))
+ return ACTION_CREATE_NEW_TABLE;
+ else
+ return ACTION_WRITE_BLOCK_ENTRY;
+
+ } else {
+ /*
+ * There's another region mapped here, don't
+ * overwrite.
+ */
+ assert(desc_type == BLOCK_DESC);
+
+ return ACTION_NONE;
+ }
+ }
+
+ } else if ((mm->base_va <= table_entry_end_va) ||
+ (mm_end_va >= table_entry_base_va)) {
+
+ /*
+ * Region partially covers table entry
+ * -----------------------------------
+ *
+ * This means that this table entry can't describe the whole
+ * translation, a finer table is needed.
+
+ * There cannot be partial block overlaps in level 3. If that
+ * happens, some of the preliminary checks when adding the
+ * mmap region failed to detect that PA and VA must at least be
+ * aligned to PAGE_SIZE.
+ */
+ assert(level < 3);
+
+ if (desc_type == INVALID_DESC) {
+ /*
+ * The block is not fully covered by the region. Create
+ * a new table, recurse into it and try to map the
+ * region with finer granularity.
+ */
+ return ACTION_CREATE_NEW_TABLE;
+
+ } else {
+ assert(desc_type == TABLE_DESC);
+ /*
+ * The block is not fully covered by the region, but
+ * there is already a table here. Recurse into it and
+ * try to map with finer granularity.
+ *
+ * PAGE_DESC for level 3 has the same value as
+ * TABLE_DESC, but this code can't run on a level 3
+ * table because there can't be overlaps in level 3.
+ */
+ return ACTION_RECURSE_INTO_TABLE;
+ }
+ }
+
+ /*
+ * This table entry is outside of the region specified in the arguments,
+ * don't write anything to it.
+ */
+ return ACTION_NONE;
+}
+
+/*
+ * Recursive function that writes to the translation tables and maps the
+ * specified region.
+ */
+static void xlat_tables_map_region(xlat_ctx_t *ctx, mmap_region_t *mm,
+ const uintptr_t table_base_va,
+ uint64_t *const table_base,
+ const int table_entries,
+ const int level)
+{
+ assert(level >= ctx->base_level && level <= XLAT_TABLE_LEVEL_MAX);
+
+ uintptr_t mm_end_va = mm->base_va + mm->size - 1;
+
+ uintptr_t table_idx_va;
+ unsigned long long table_idx_pa;
+
+ uint64_t *subtable;
+ uint64_t desc;
+
+ int table_idx;
+
+ if (mm->base_va > table_base_va) {
+ /* Find the first index of the table affected by the region. */
+ table_idx_va = mm->base_va & ~XLAT_BLOCK_MASK(level);
+
+ table_idx = (table_idx_va - table_base_va) >>
+ XLAT_ADDR_SHIFT(level);
+
+ assert(table_idx < table_entries);
+ } else {
+ /* Start from the beginning of the table. */
+ table_idx_va = table_base_va;
+ table_idx = 0;
+ }
+
+ while (table_idx < table_entries) {
+
+ desc = table_base[table_idx];
+
+ table_idx_pa = mm->base_pa + table_idx_va - mm->base_va;
+
+ action_t action = xlat_tables_map_region_action(mm,
+ desc & DESC_MASK, table_idx_pa, table_idx_va, level);
+
+ if (action == ACTION_WRITE_BLOCK_ENTRY) {
+
+ table_base[table_idx] =
+ xlat_desc(mm->attr, table_idx_pa, level);
+
+ } else if (action == ACTION_CREATE_NEW_TABLE) {
+
+ subtable = xlat_table_get_empty(ctx);
+ assert(subtable != NULL);
+ /* Recurse to write into subtable */
+ xlat_tables_map_region(ctx, mm, table_idx_va, subtable,
+ XLAT_TABLE_ENTRIES, level + 1);
+ /* Point to new subtable from this one. */
+ table_base[table_idx] =
+ TABLE_DESC | (unsigned long)subtable;
+
+ } else if (action == ACTION_RECURSE_INTO_TABLE) {
+
+ subtable = (uint64_t *)(uintptr_t)(desc & TABLE_ADDR_MASK);
+ /* Recurse to write into subtable */
+ xlat_tables_map_region(ctx, mm, table_idx_va, subtable,
+ XLAT_TABLE_ENTRIES, level + 1);
+
+ } else {
+
+ assert(action == ACTION_NONE);
+
+ }
+
+ table_idx++;
+ table_idx_va += XLAT_BLOCK_SIZE(level);
+
+ /* If reached the end of the region, exit */
+ if (mm_end_va <= table_idx_va)
+ break;
+ }
+}
+
+void print_mmap(mmap_region_t *const mmap)
+{
+#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
+ tf_printf("mmap:\n");
+ mmap_region_t *mm = mmap;
+
+ while (mm->size) {
+ tf_printf(" VA:%p PA:0x%llx size:0x%zx attr:0x%x\n",
+ (void *)mm->base_va, mm->base_pa,
+ mm->size, mm->attr);
+ ++mm;
+ };
+ tf_printf("\n");
+#endif
+}
+
+/*
+ * Function that verifies that a region can be mapped.
+ * Returns:
+ * 0: Success, the mapping is allowed.
+ * EINVAL: Invalid values were used as arguments.
+ * ERANGE: The memory limits were surpassed.
+ * ENOMEM: There is not enough memory in the mmap array.
+ * EPERM: Region overlaps another one in an invalid way.
+ */
+static int mmap_add_region_check(xlat_ctx_t *ctx, unsigned long long base_pa,
+ uintptr_t base_va, size_t size,
+ unsigned int attr)
+{
+ mmap_region_t *mm = ctx->mmap;
+ unsigned long long end_pa = base_pa + size - 1;
+ uintptr_t end_va = base_va + size - 1;
+
+ if (!IS_PAGE_ALIGNED(base_pa) || !IS_PAGE_ALIGNED(base_va) ||
+ !IS_PAGE_ALIGNED(size))
+ return -EINVAL;
+
+ /* Check for overflows */
+ if ((base_pa > end_pa) || (base_va > end_va))
+ return -ERANGE;
+
+ if ((base_va + (uintptr_t)size - (uintptr_t)1) > ctx->va_max_address)
+ return -ERANGE;
+
+ if ((base_pa + (unsigned long long)size - 1ULL) > ctx->pa_max_address)
+ return -ERANGE;
+
+ /* Check that there is space in the mmap array */
+ if (ctx->mmap[ctx->mmap_num - 1].size != 0)
+ return -ENOMEM;
+
+ /* Check for PAs and VAs overlaps with all other regions */
+ for (mm = ctx->mmap; mm->size; ++mm) {
+
+ uintptr_t mm_end_va = mm->base_va + mm->size - 1;
+
+ /*
+ * Check if one of the regions is completely inside the other
+ * one.
+ */
+ int fully_overlapped_va =
+ ((base_va >= mm->base_va) && (end_va <= mm_end_va)) ||
+ ((mm->base_va >= base_va) && (mm_end_va <= end_va));
+
+ /*
+ * Full VA overlaps are only allowed if both regions are
+ * identity mapped (zero offset) or have the same VA to PA
+ * offset. Also, make sure that it's not the exact same area.
+ * This can only be done with locked regions.
+ */
+ if (fully_overlapped_va) {
+
+ if ((mm->base_va - mm->base_pa) != (base_va - base_pa))
+ return -EPERM;
+
+ if ((base_va == mm->base_va) && (size == mm->size))
+ return -EPERM;
+
+ } else {
+ /*
+ * If the regions do not have fully overlapping VAs,
+ * then they must have fully separated VAs and PAs.
+ * Partial overlaps are not allowed
+ */
+
+ unsigned long long mm_end_pa =
+ mm->base_pa + mm->size - 1;
+
+ int separated_pa =
+ (end_pa < mm->base_pa) || (base_pa > mm_end_pa);
+ int separated_va =
+ (end_va < mm->base_va) || (base_va > mm_end_va);
+
+ if (!(separated_va && separated_pa))
+ return -EPERM;
+ }
+ }
+
+ return 0;
+}
+
+void mmap_add_region_ctx(xlat_ctx_t *ctx, mmap_region_t *mm)
+{
+ mmap_region_t *mm_cursor = ctx->mmap;
+ mmap_region_t *mm_last = mm_cursor + ctx->mmap_num;
+ unsigned long long end_pa = mm->base_pa + mm->size - 1;
+ uintptr_t end_va = mm->base_va + mm->size - 1;
+ int ret;
+
+ /* Ignore empty regions */
+ if (!mm->size)
+ return;
+
+ ret = mmap_add_region_check(ctx, mm->base_pa, mm->base_va, mm->size,
+ mm->attr);
+ if (ret != 0) {
+ ERROR("mmap_add_region_check() failed. error %d\n", ret);
+ assert(0);
+ return;
+ }
+
+ /*
+ * Find correct place in mmap to insert new region.
+ *
+ * 1 - Lower region VA end first.
+ * 2 - Smaller region size first.
+ *
+ * VA 0 0xFF
+ *
+ * 1st |------|
+ * 2nd |------------|
+ * 3rd |------|
+ * 4th |---|
+ * 5th |---|
+ * 6th |----------|
+ * 7th |-------------------------------------|
+ *
+ * This is required for overlapping regions only. It simplifies adding
+ * regions with the loop in xlat_tables_init_internal because the outer
+ * ones won't overwrite block or page descriptors of regions added
+ * previously.
+ */
+
+ while ((mm_cursor->base_va + mm_cursor->size - 1) < end_va
+ && mm_cursor->size)
+ ++mm_cursor;
+
+ while ((mm_cursor->base_va + mm_cursor->size - 1 == end_va)
+ && (mm_cursor->size < mm->size))
+ ++mm_cursor;
+
+ /* Make room for new region by moving other regions up by one place */
+ memmove(mm_cursor + 1, mm_cursor,
+ (uintptr_t)mm_last - (uintptr_t)mm_cursor);
+
+ /*
+ * Check we haven't lost the empty sentinel from the end of the array.
+ * This shouldn't happen as we have checked in mmap_add_region_check
+ * that there is free space.
+ */
+ assert(mm_last->size == 0);
+
+ mm_cursor->base_pa = mm->base_pa;
+ mm_cursor->base_va = mm->base_va;
+ mm_cursor->size = mm->size;
+ mm_cursor->attr = mm->attr;
+
+ if (end_pa > ctx->max_pa)
+ ctx->max_pa = end_pa;
+ if (end_va > ctx->max_va)
+ ctx->max_va = end_va;
+}
+
+#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
+
+/* Print the attributes of the specified block descriptor. */
+static void xlat_desc_print(uint64_t desc)
+{
+ int mem_type_index = ATTR_INDEX_GET(desc);
+
+ 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");
+ }
+
+ tf_printf(LOWER_ATTRS(AP_RO) & desc ? "-RO" : "-RW");
+ tf_printf(LOWER_ATTRS(NS) & desc ? "-NS" : "-S");
+ tf_printf(UPPER_ATTRS(XN) & desc ? "-XN" : "-EXEC");
+}
+
+static const char * const level_spacers[] = {
+ "",
+ " ",
+ " ",
+ " "
+};
+
+/*
+ * Recursive function that reads the translation tables passed as an argument
+ * and prints their status.
+ */
+static void xlat_tables_print_internal(const uintptr_t table_base_va,
+ uint64_t *const table_base, const int table_entries,
+ const 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);
+
+ while (table_idx < table_entries) {
+
+ desc = table_base[table_idx];
+
+ if ((desc & DESC_MASK) == INVALID_DESC) {
+
+ tf_printf("%sVA:%p size:0x%zx\n",
+ level_spacers[level],
+ (void *)table_idx_va, level_size);
+
+ } else {
+
+ /*
+ * 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(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(desc);
+ tf_printf("\n");
+ }
+ }
+
+ table_idx++;
+ table_idx_va += level_size;
+ }
+}
+
+#endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */
+
+void xlat_tables_print(xlat_ctx_t *ctx)
+{
+#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
+ xlat_tables_print_internal(0, ctx->base_table, ctx->base_table_entries,
+ ctx->base_level);
+#endif /* LOG_LEVEL >= LOG_LEVEL_VERBOSE */
+}
+
+void init_xlation_table(xlat_ctx_t *ctx)
+{
+ mmap_region_t *mm = ctx->mmap;
+
+ /* All tables must be zeroed before mapping any region. */
+
+ for (int i = 0; i < ctx->base_table_entries; i++)
+ ctx->base_table[i] = INVALID_DESC;
+
+ for (int j = 0; j < ctx->tables_num; j++) {
+ for (int i = 0; i < XLAT_TABLE_ENTRIES; i++)
+ ctx->tables[j][i] = INVALID_DESC;
+ }
+
+ while (mm->size)
+ xlat_tables_map_region(ctx, mm++, 0, ctx->base_table,
+ ctx->base_table_entries, ctx->base_level);
+
+ ctx->initialized = 1;
+}