diff options
Diffstat (limited to 'arch/arm64/kernel/head.S')
| -rw-r--r-- | arch/arm64/kernel/head.S | 245 |
1 files changed, 172 insertions, 73 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index e3cb9fbf96b6..ba3ab04788dc 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -148,6 +148,26 @@ preserve_boot_args: ENDPROC(preserve_boot_args) /* + * Macro to arrange a physical address in a page table entry, taking care of + * 52-bit addresses. + * + * Preserves: phys + * Returns: pte + */ + .macro phys_to_pte, phys, pte +#ifdef CONFIG_ARM64_PA_BITS_52 + /* + * We assume \phys is 64K aligned and this is guaranteed by only + * supporting this configuration with 64K pages. + */ + orr \pte, \phys, \phys, lsr #36 + and \pte, \pte, #PTE_ADDR_MASK +#else + mov \pte, \phys +#endif + .endm + +/* * Macro to create a table entry to the next page. * * tbl: page table address @@ -156,54 +176,124 @@ 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 - lsr \tmp1, \virt, #\shift - and \tmp1, \tmp1, #\ptrs - 1 // table index - add \tmp2, \tbl, #PAGE_SIZE + add \tmp1, \tbl, #PAGE_SIZE + phys_to_pte \tmp1, \tmp2 orr \tmp2, \tmp2, #PMD_TYPE_TABLE // address of next table and entry type + lsr \tmp1, \virt, #\shift + 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 /* - * Macro to populate the PGD (and possibily PUD) for the corresponding - * block entry in the next level (tbl) for the given virtual address. + * Macro to populate page table entries, these entries can be pointers to the next level + * or last level entries pointing to physical memory. + * + * tbl: page table address + * rtbl: pointer to page table or physical memory + * index: start index to write + * eindex: end index to write - [index, eindex] written to + * flags: flags for pagetable entry to or in + * inc: increment to rtbl between each entry + * tmp1: temporary variable * - * Preserves: tbl, next, virt - * Corrupts: tmp1, tmp2 + * Preserves: tbl, eindex, flags, inc + * Corrupts: index, tmp1 + * Returns: rtbl */ - .macro create_pgd_entry, tbl, virt, 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 -#endif -#if SWAPPER_PGTABLE_LEVELS > 2 - create_table_entry \tbl, \virt, SWAPPER_TABLE_SHIFT, PTRS_PER_PTE, \tmp1, \tmp2 -#endif + .macro populate_entries, tbl, rtbl, index, eindex, flags, inc, tmp1 +.Lpe\@: phys_to_pte \rtbl, \tmp1 + orr \tmp1, \tmp1, \flags // tmp1 = table entry + str \tmp1, [\tbl, \index, lsl #3] + add \rtbl, \rtbl, \inc // rtbl = pa next level + add \index, \index, #1 + cmp \index, \eindex + b.ls .Lpe\@ + .endm + +/* + * Compute indices of table entries from virtual address range. If multiple entries + * were needed in the previous page table level then the next page table level is assumed + * to be composed of multiple pages. (This effectively scales the end index). + * + * vstart: virtual address of start of range + * vend: virtual address of end of range + * shift: shift used to transform virtual address into index + * ptrs: number of entries in page table + * istart: index in table corresponding to vstart + * iend: index in table corresponding to vend + * count: On entry: how many extra entries were required in previous level, scales + * our end index. + * On exit: returns how many extra entries required for next page table level + * + * Preserves: vstart, vend, shift, ptrs + * Returns: istart, iend, count + */ + .macro compute_indices, vstart, vend, shift, ptrs, istart, iend, count + lsr \iend, \vend, \shift + mov \istart, \ptrs + sub \istart, \istart, #1 + and \iend, \iend, \istart // iend = (vend >> shift) & (ptrs - 1) + mov \istart, \ptrs + mul \istart, \istart, \count + add \iend, \iend, \istart // iend += (count - 1) * ptrs + // our entries span multiple tables + + lsr \istart, \vstart, \shift + mov \count, \ptrs + sub \count, \count, #1 + and \istart, \istart, \count + + sub \count, \iend, \istart .endm /* - * Macro to populate block entries in the page table for the start..end - * virtual range (inclusive). + * Map memory for specified virtual address range. Each level of page table needed supports + * multiple entries. If a level requires n entries the next page table level is assumed to be + * formed from n pages. + * + * tbl: location of page table + * rtbl: address to be used for first level page table entry (typically tbl + PAGE_SIZE) + * vstart: start address to map + * vend: end address to map - we map [vstart, vend] + * flags: flags to use to map last level entries + * phys: physical address corresponding to vstart - physical memory is contiguous + * pgds: the number of pgd entries * - * Preserves: tbl, flags - * Corrupts: phys, start, end, pstate + * Temporaries: istart, iend, tmp, count, sv - these need to be different registers + * Preserves: vstart, vend, flags + * Corrupts: tbl, rtbl, istart, iend, tmp, count, sv */ - .macro create_block_map, tbl, flags, phys, start, end - lsr \phys, \phys, #SWAPPER_BLOCK_SHIFT - lsr \start, \start, #SWAPPER_BLOCK_SHIFT - and \start, \start, #PTRS_PER_PTE - 1 // table index - orr \phys, \flags, \phys, lsl #SWAPPER_BLOCK_SHIFT // table entry - lsr \end, \end, #SWAPPER_BLOCK_SHIFT - and \end, \end, #PTRS_PER_PTE - 1 // table end index -9999: str \phys, [\tbl, \start, lsl #3] // store the entry - add \start, \start, #1 // next entry - add \phys, \phys, #SWAPPER_BLOCK_SIZE // next block - cmp \start, \end - b.ls 9999b + .macro map_memory, tbl, rtbl, vstart, vend, flags, phys, pgds, istart, iend, tmp, count, sv + add \rtbl, \tbl, #PAGE_SIZE + mov \sv, \rtbl + mov \count, #0 + compute_indices \vstart, \vend, #PGDIR_SHIFT, \pgds, \istart, \iend, \count + populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp + mov \tbl, \sv + mov \sv, \rtbl + +#if SWAPPER_PGTABLE_LEVELS > 3 + compute_indices \vstart, \vend, #PUD_SHIFT, #PTRS_PER_PUD, \istart, \iend, \count + populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp + mov \tbl, \sv + mov \sv, \rtbl +#endif + +#if SWAPPER_PGTABLE_LEVELS > 2 + compute_indices \vstart, \vend, #SWAPPER_TABLE_SHIFT, #PTRS_PER_PMD, \istart, \iend, \count + populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp + mov \tbl, \sv +#endif + + compute_indices \vstart, \vend, #SWAPPER_BLOCK_SHIFT, #PTRS_PER_PTE, \istart, \iend, \count + bic \count, \phys, #SWAPPER_BLOCK_SIZE - 1 + populate_entries \tbl, \count, \istart, \iend, \flags, #SWAPPER_BLOCK_SIZE, \tmp .endm /* @@ -221,14 +311,16 @@ __create_page_tables: * dirty cache lines being evicted. */ adrp x0, idmap_pg_dir - ldr x1, =(IDMAP_DIR_SIZE + SWAPPER_DIR_SIZE + RESERVED_TTBR0_SIZE) + adrp x1, swapper_pg_end + sub x1, x1, x0 bl __inval_dcache_area /* * Clear the idmap and swapper page tables. */ adrp x0, idmap_pg_dir - ldr x1, =(IDMAP_DIR_SIZE + SWAPPER_DIR_SIZE + RESERVED_TTBR0_SIZE) + adrp x1, swapper_pg_end + sub x1, x1, x0 1: stp xzr, xzr, [x0], #16 stp xzr, xzr, [x0], #16 stp xzr, xzr, [x0], #16 @@ -244,26 +336,13 @@ __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 @@ -272,21 +351,44 @@ __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 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 + + map_memory x0, x1, x3, x6, x7, x3, x4, x10, x11, x12, x13, x14 /* * Map the kernel image (starting with PHYS_OFFSET). @@ -294,12 +396,13 @@ __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 adrp x6, _end // runtime __pa(_end) adrp x3, _text // runtime __pa(_text) sub x6, x6, x3 // _end - _text add x6, x6, x5 // runtime __va(_end) - create_block_map x0, x7, x3, x5, x6 + + map_memory x0, x1, x5, x6, x7, x3, x4, x10, x11, x12, x13, x14 /* * Since the page tables have been populated with non-cacheable @@ -307,7 +410,8 @@ __create_page_tables: * tables again to remove any speculatively loaded cache lines. */ adrp x0, idmap_pg_dir - ldr x1, =(IDMAP_DIR_SIZE + SWAPPER_DIR_SIZE + RESERVED_TTBR0_SIZE) + adrp x1, swapper_pg_end + sub x1, x1, x0 dmb sy bl __inval_dcache_area @@ -388,17 +492,13 @@ ENTRY(el2_setup) mrs x0, CurrentEL cmp x0, #CurrentEL_EL2 b.eq 1f - mrs x0, sctlr_el1 -CPU_BE( orr x0, x0, #(3 << 24) ) // Set the EE and E0E bits for EL1 -CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1 + mov_q x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1) msr sctlr_el1, x0 mov w0, #BOOT_CPU_MODE_EL1 // This cpu booted in EL1 isb ret -1: mrs x0, sctlr_el2 -CPU_BE( orr x0, x0, #(1 << 25) ) // Set the EE bit for EL2 -CPU_LE( bic x0, x0, #(1 << 25) ) // Clear the EE bit for EL2 +1: mov_q x0, (SCTLR_EL2_RES1 | ENDIAN_SET_EL2) msr sctlr_el2, x0 #ifdef CONFIG_ARM64_VHE @@ -514,10 +614,7 @@ install_el2_stub: * requires no configuration, and all non-hyp-specific EL2 setup * will be done via the _EL1 system register aliases in __cpu_setup. */ - /* sctlr_el1 */ - mov x0, #0x0800 // Set/clear RES{1,0} bits -CPU_BE( movk x0, #0x33d0, lsl #16 ) // Set EE and E0E on BE systems -CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems + mov_q x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1) msr sctlr_el1, x0 /* Coprocessor traps. */ @@ -679,8 +776,10 @@ ENTRY(__enable_mmu) update_early_cpu_boot_status 0, x1, x2 adrp x1, idmap_pg_dir adrp x2, swapper_pg_dir - msr ttbr0_el1, x1 // load TTBR0 - msr ttbr1_el1, x2 // load TTBR1 + phys_to_ttbr x1, x3 + phys_to_ttbr x2, x4 + msr ttbr0_el1, x3 // load TTBR0 + msr ttbr1_el1, x4 // load TTBR1 isb msr sctlr_el1, x0 isb |