diff options
Diffstat (limited to 'arch/arm64/kernel/head.S')
| -rw-r--r-- | arch/arm64/kernel/head.S | 76 |
1 files changed, 45 insertions, 31 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index eeec0001e204..66f01869e97c 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -176,7 +176,7 @@ ENDPROC(preserve_boot_args) * ptrs: #imm pointers per table page * * Preserves: virt - * Corrupts: tmp1, tmp2 + * Corrupts: ptrs, tmp1, tmp2 * Returns: tbl -> next level table page address */ .macro create_table_entry, tbl, virt, shift, ptrs, tmp1, tmp2 @@ -184,7 +184,8 @@ ENDPROC(preserve_boot_args) phys_to_pte \tmp1, \tmp2 orr \tmp2, \tmp2, #PMD_TYPE_TABLE // address of next table and entry type lsr \tmp1, \virt, #\shift - and \tmp1, \tmp1, #\ptrs - 1 // table index + sub \ptrs, \ptrs, #1 + and \tmp1, \tmp1, \ptrs // table index str \tmp2, [\tbl, \tmp1, lsl #3] add \tbl, \tbl, #PAGE_SIZE // next level table page .endm @@ -194,15 +195,17 @@ ENDPROC(preserve_boot_args) * block entry in the next level (tbl) for the given virtual address. * * Preserves: tbl, next, virt - * Corrupts: tmp1, tmp2 + * Corrupts: ptrs_per_pgd, tmp1, tmp2 */ - .macro create_pgd_entry, tbl, virt, tmp1, tmp2 - create_table_entry \tbl, \virt, PGDIR_SHIFT, PTRS_PER_PGD, \tmp1, \tmp2 + .macro create_pgd_entry, tbl, virt, ptrs_per_pgd, tmp1, tmp2 + create_table_entry \tbl, \virt, PGDIR_SHIFT, \ptrs_per_pgd, \tmp1, \tmp2 #if SWAPPER_PGTABLE_LEVELS > 3 - create_table_entry \tbl, \virt, PUD_SHIFT, PTRS_PER_PUD, \tmp1, \tmp2 + mov \ptrs_per_pgd, PTRS_PER_PUD + create_table_entry \tbl, \virt, PUD_SHIFT, \ptrs_per_pgd, \tmp1, \tmp2 #endif #if SWAPPER_PGTABLE_LEVELS > 2 - create_table_entry \tbl, \virt, SWAPPER_TABLE_SHIFT, PTRS_PER_PTE, \tmp1, \tmp2 + mov \ptrs_per_pgd, PTRS_PER_PTE + create_table_entry \tbl, \virt, SWAPPER_TABLE_SHIFT, \ptrs_per_pgd, \tmp1, \tmp2 #endif .endm @@ -266,26 +269,13 @@ __create_page_tables: adrp x0, idmap_pg_dir adrp x3, __idmap_text_start // __pa(__idmap_text_start) -#ifndef CONFIG_ARM64_VA_BITS_48 -#define EXTRA_SHIFT (PGDIR_SHIFT + PAGE_SHIFT - 3) -#define EXTRA_PTRS (1 << (48 - EXTRA_SHIFT)) - - /* - * If VA_BITS < 48, it may be too small to allow for an ID mapping to be - * created that covers system RAM if that is located sufficiently high - * in the physical address space. So for the ID map, use an extended - * virtual range in that case, by configuring an additional translation - * level. - * First, we have to verify our assumption that the current value of - * VA_BITS was chosen such that all translation levels are fully - * utilised, and that lowering T0SZ will always result in an additional - * translation level to be configured. - */ -#if VA_BITS != EXTRA_SHIFT -#error "Mismatch between VA_BITS and page size/number of translation levels" -#endif - /* + * VA_BITS may be too small to allow for an ID mapping to be created + * that covers system RAM if that is located sufficiently high in the + * physical address space. So for the ID map, use an extended virtual + * range in that case, and configure an additional translation level + * if needed. + * * Calculate the maximum allowed value for TCR_EL1.T0SZ so that the * entire ID map region can be mapped. As T0SZ == (64 - #bits used), * this number conveniently equals the number of leading zeroes in @@ -294,18 +284,41 @@ __create_page_tables: adrp x5, __idmap_text_end clz x5, x5 cmp x5, TCR_T0SZ(VA_BITS) // default T0SZ small enough? - b.ge 1f // .. then skip additional level + b.ge 1f // .. then skip VA range extension adr_l x6, idmap_t0sz str x5, [x6] dmb sy dc ivac, x6 // Invalidate potentially stale cache line - create_table_entry x0, x3, EXTRA_SHIFT, EXTRA_PTRS, x5, x6 -1: +#if (VA_BITS < 48) +#define EXTRA_SHIFT (PGDIR_SHIFT + PAGE_SHIFT - 3) +#define EXTRA_PTRS (1 << (PHYS_MASK_SHIFT - EXTRA_SHIFT)) + + /* + * If VA_BITS < 48, we have to configure an additional table level. + * First, we have to verify our assumption that the current value of + * VA_BITS was chosen such that all translation levels are fully + * utilised, and that lowering T0SZ will always result in an additional + * translation level to be configured. + */ +#if VA_BITS != EXTRA_SHIFT +#error "Mismatch between VA_BITS and page size/number of translation levels" #endif - create_pgd_entry x0, x3, x5, x6 + mov x4, EXTRA_PTRS + create_table_entry x0, x3, EXTRA_SHIFT, x4, x5, x6 +#else + /* + * If VA_BITS == 48, we don't have to configure an additional + * translation level, but the top-level table has more entries. + */ + mov x4, #1 << (PHYS_MASK_SHIFT - PGDIR_SHIFT) + str_l x4, idmap_ptrs_per_pgd, x5 +#endif +1: + ldr_l x4, idmap_ptrs_per_pgd + create_pgd_entry x0, x3, x4, x5, x6 mov x5, x3 // __pa(__idmap_text_start) adr_l x6, __idmap_text_end // __pa(__idmap_text_end) create_block_map x0, x7, x3, x5, x6, x4 @@ -316,7 +329,8 @@ __create_page_tables: adrp x0, swapper_pg_dir mov_q x5, KIMAGE_VADDR + TEXT_OFFSET // compile time __va(_text) add x5, x5, x23 // add KASLR displacement - create_pgd_entry x0, x5, x3, x6 + mov x4, PTRS_PER_PGD + create_pgd_entry x0, x5, x4, x3, x6 adrp x6, _end // runtime __pa(_end) adrp x3, _text // runtime __pa(_text) sub x6, x6, x3 // _end - _text |