diff options
Diffstat (limited to 'payloads/libpayload/arch/arm64/mmu.c')
| -rw-r--r-- | payloads/libpayload/arch/arm64/mmu.c | 193 |
1 files changed, 73 insertions, 120 deletions
diff --git a/payloads/libpayload/arch/arm64/mmu.c b/payloads/libpayload/arch/arm64/mmu.c index f0781f5ec1..e2a0cb18b6 100644 --- a/payloads/libpayload/arch/arm64/mmu.c +++ b/payloads/libpayload/arch/arm64/mmu.c @@ -44,6 +44,12 @@ static uint64_t *xlat_addr; static int free_idx; static uint8_t ttb_buffer[TTB_DEFAULT_SIZE] __attribute__((aligned(GRANULE_SIZE))); +static const char * const tag_to_string[] = { + [TYPE_NORMAL_MEM] = "normal", + [TYPE_DEV_MEM] = "device", + [TYPE_DMA_MEM] = "uncached", +}; + /* * The usedmem_ranges is used to describe all the memory ranges that are * actually used by payload i.e. _start -> _end in linker script and the @@ -56,25 +62,12 @@ static uint8_t ttb_buffer[TTB_DEFAULT_SIZE] __attribute__((aligned(GRANULE_SIZE) */ static struct mmu_ranges usedmem_ranges; -static const uint64_t level_to_addr_mask[] = { - L1_ADDR_MASK, - L2_ADDR_MASK, - L3_ADDR_MASK, -}; - -static const uint64_t level_to_addr_shift[] = { - L1_ADDR_SHIFT, - L2_ADDR_SHIFT, - L3_ADDR_SHIFT, -}; - static void __attribute__((noreturn)) mmu_error(void) { halt(); } -/* - * Func : get_block_attr +/* Func : get_block_attr * Desc : Get block descriptor attributes based on the value of tag in memrange * region */ @@ -107,21 +100,7 @@ static uint64_t get_block_attr(unsigned long tag) return attr; } -/* - * Func : get_index_from_addr - * Desc : Get index into table at a given level using appropriate bits from the - * base address - */ -static uint64_t get_index_from_addr(uint64_t addr, uint8_t level) -{ - uint64_t mask = level_to_addr_mask[level-1]; - uint8_t shift = level_to_addr_shift[level-1]; - - return ((addr & mask) >> shift); -} - -/* - * Func : table_desc_valid +/* Func : table_desc_valid * Desc : Check if a table entry contains valid desc */ static uint64_t table_desc_valid(uint64_t desc) @@ -129,29 +108,34 @@ static uint64_t table_desc_valid(uint64_t desc) return((desc & TABLE_DESC) == TABLE_DESC); } -/* - * Func : get_new_table - * Desc : Return the next free XLAT table from ttb buffer +/* Func : setup_new_table + * Desc : Get next free table from TTB and set it up to match old parent entry. */ -static uint64_t *get_new_table(void) +static uint64_t *setup_new_table(uint64_t desc, size_t xlat_size) { - uint64_t *new; + uint64_t *new, *entry; - if (free_idx >= max_tables) { - printf("ARM64 MMU: No free table\n"); - return NULL; - } + assert(free_idx < max_tables); new = (uint64_t*)((unsigned char *)xlat_addr + free_idx * GRANULE_SIZE); free_idx++; - memset(new, 0, GRANULE_SIZE); + if (!desc) { + memset(new, 0, GRANULE_SIZE); + } else { + /* Can reuse old parent entry, but may need to adjust type. */ + if (xlat_size == L3_XLAT_SIZE) + desc |= PAGE_DESC; + + for (entry = new; (u8 *)entry < (u8 *)new + GRANULE_SIZE; + entry++, desc += xlat_size) + *entry = desc; + } return new; } -/* - * Func : get_table_from_desc +/* Func : get_table_from_desc * Desc : Get next level table address from table descriptor */ static uint64_t *get_table_from_desc(uint64_t desc) @@ -160,27 +144,23 @@ static uint64_t *get_table_from_desc(uint64_t desc) return ptr; } -/* - * Func: get_next_level_table - * Desc: Check if the table entry is a valid descriptor. If not, allocate new +/* Func: get_next_level_table + * Desc: Check if the table entry is a valid descriptor. If not, initialize new * table, update the entry and return the table addr. If valid, return the addr. */ -static uint64_t *get_next_level_table(uint64_t *ptr) +static uint64_t *get_next_level_table(uint64_t *ptr, size_t xlat_size) { uint64_t desc = *ptr; if (!table_desc_valid(desc)) { - uint64_t *new_table = get_new_table(); - if (new_table == NULL) - return NULL; + uint64_t *new_table = setup_new_table(desc, xlat_size); desc = ((uint64_t)new_table) | TABLE_DESC; *ptr = desc; } return get_table_from_desc(desc); } -/* - * Func : init_xlat_table +/* Func : init_xlat_table * Desc : Given a base address and size, it identifies the indices within * different level XLAT tables which map the given base addr. Similar to table * walk, except that all invalid entries during the walk are updated @@ -191,18 +171,16 @@ static uint64_t init_xlat_table(uint64_t base_addr, uint64_t size, uint64_t tag) { - uint64_t l1_index = get_index_from_addr(base_addr,1); - uint64_t l2_index = get_index_from_addr(base_addr,2); - uint64_t l3_index = get_index_from_addr(base_addr,3); + uint64_t l1_index = (base_addr & L1_ADDR_MASK) >> L1_ADDR_SHIFT; + uint64_t l2_index = (base_addr & L2_ADDR_MASK) >> L2_ADDR_SHIFT; + uint64_t l3_index = (base_addr & L3_ADDR_MASK) >> L3_ADDR_SHIFT; uint64_t *table = xlat_addr; uint64_t desc; uint64_t attr = get_block_attr(tag); - /* - * L1 table lookup + /* L1 table lookup * If VA has bits more than L2 can resolve, lookup starts at L1 - * Assumption: we don't need L0 table in coreboot - */ + * Assumption: we don't need L0 table in coreboot */ if (BITS_PER_VA > L1_ADDR_SHIFT) { if ((size >= L1_XLAT_SIZE) && IS_ALIGNED(base_addr, (1UL << L1_ADDR_SHIFT))) { @@ -213,94 +191,71 @@ static uint64_t init_xlat_table(uint64_t base_addr, table[l1_index] = desc; /* L2 lookup is not required */ return L1_XLAT_SIZE; - } else { - table = get_next_level_table(&table[l1_index]); - if (!table) - return 0; } + table = get_next_level_table(&table[l1_index], L2_XLAT_SIZE); } - /* - * L2 table lookup + /* L2 table lookup * If lookup was performed at L1, L2 table addr is obtained from L1 desc - * else, lookup starts at ttbr address - */ + * else, lookup starts at ttbr address */ if ((size >= L2_XLAT_SIZE) && IS_ALIGNED(base_addr, (1UL << L2_ADDR_SHIFT))) { - /* - * If block address is aligned and size is greater than or equal - * to size addressed by each L2 entry, we can - * directly store a block desc - */ + /* If block address is aligned and size is greater than + * or equal to size addressed by each L2 entry, we can + * directly store a block desc */ desc = base_addr | BLOCK_DESC | attr; table[l2_index] = desc; /* L3 lookup is not required */ return L2_XLAT_SIZE; - } else { - /* L2 entry stores a table descriptor */ - table = get_next_level_table(&table[l2_index]); - if (!table) - return 0; } + /* L2 entry stores a table descriptor */ + table = get_next_level_table(&table[l2_index], L3_XLAT_SIZE); + /* L3 table lookup */ desc = base_addr | PAGE_DESC | attr; table[l3_index] = desc; return L3_XLAT_SIZE; } -/* - * Func : sanity_check - * Desc : Check if the address is aligned and size is atleast the granule size +/* Func : sanity_check + * Desc : Check address/size alignment of a table or page. */ -static uint64_t sanity_check(uint64_t addr, - uint64_t size) +static void sanity_check(uint64_t addr, uint64_t size) { - /* Address should be atleast 64 KiB aligned */ - if (addr & GRANULE_SIZE_MASK) - return 1; - - /* Size should be atleast granule size */ - if (size < GRANULE_SIZE) - return 1; - - return 0; + assert(!(addr & GRANULE_SIZE_MASK) && + !(size & GRANULE_SIZE_MASK) && + size >= GRANULE_SIZE); } -/* - * Func : init_mmap_entry - * Desc : For each mmap entry, this function calls init_xlat_table with the base +/* Func : mmu_config_range + * Desc : This function repeatedly calls init_xlat_table with the base * address. Based on size returned from init_xlat_table, base_addr is updated * and subsequent calls are made for initializing the xlat table until the whole * region is initialized. */ -static void init_mmap_entry(struct mmu_memrange *r) +void mmu_config_range(void *start, size_t size, uint64_t tag) { - uint64_t base_addr = r->base; - uint64_t size = r->size; - uint64_t tag = r->type; + uint64_t base_addr = (uintptr_t)start; uint64_t temp_size = size; - while (temp_size) { - uint64_t ret; - - if (sanity_check(base_addr,temp_size)) { - printf("Libpayload: ARM64 MMU: sanity check failed\n"); - return; - } - - ret = init_xlat_table(base_addr + (size - temp_size), - temp_size, tag); + assert(tag < ARRAY_SIZE(tag_to_string)); + printf("Libpayload: ARM64 MMU: Mapping address range [%p:%p) as %s\n", + start, start + size, tag_to_string[tag]); + sanity_check(base_addr, temp_size); - if (ret == 0) - return; + while (temp_size) + temp_size -= init_xlat_table(base_addr + (size - temp_size), + temp_size, tag); - temp_size -= ret; - } + /* ARMv8 MMUs snoop L1 data cache, no need to flush it. */ + dsb(); + tlbiall_current(); + dsb(); + isb(); } -/* - * Func : mmu_init +/* Func : mmu_init * Desc : Initialize mmu based on the mmu_memrange passed. ttb_buffer is used as * the base address for xlat tables. TTB_DEFAULT_SIZE defines the max number of * tables that can be used @@ -308,8 +263,6 @@ static void init_mmap_entry(struct mmu_memrange *r) */ uint64_t mmu_init(struct mmu_ranges *mmu_ranges) { - struct mmu_memrange devrange = { 0, 0x80000000, TYPE_DEV_MEM }; - int i = 0; xlat_addr = (uint64_t *)&ttb_buffer; @@ -321,11 +274,12 @@ uint64_t mmu_init(struct mmu_ranges *mmu_ranges) printf("Libpayload ARM64: TTB_BUFFER: 0x%p Max Tables: %d\n", (void*)xlat_addr, max_tables); - init_mmap_entry(&devrange); + mmu_config_range(NULL, 0x80000000, TYPE_DEV_MEM); - for (; i < mmu_ranges->used; i++) { - init_mmap_entry(&mmu_ranges->entries[i]); - } + for (; i < mmu_ranges->used; i++) + mmu_config_range((void *)mmu_ranges->entries[i].base, + mmu_ranges->entries[i].size, + mmu_ranges->entries[i].type); printf("Libpayload ARM64: MMU init done\n"); return 0; @@ -388,8 +342,7 @@ void mmu_enable(void) /* Initialize TTBR */ raw_write_ttbr0_current((uintptr_t)xlat_addr); - /* Ensure all translation table writes are committed before enabling MMU */ - dsb(); + /* Ensure system register writes are committed before enabling MMU */ isb(); /* Enable MMU */ |