diff options
Diffstat (limited to 'arch/arm64/kernel/head.S')
| -rw-r--r-- | arch/arm64/kernel/head.S | 121 |
1 files changed, 76 insertions, 45 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index a2c1195abb7f..144f10567f82 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -22,6 +22,7 @@ #include <linux/linkage.h> #include <linux/init.h> +#include <linux/irqchip/arm-gic-v3.h> #include <asm/assembler.h> #include <asm/ptrace.h> @@ -35,37 +36,31 @@ #include <asm/page.h> #include <asm/virt.h> -/* - * swapper_pg_dir is the virtual address of the initial page table. We place - * the page tables 3 * PAGE_SIZE below KERNEL_RAM_VADDR. The idmap_pg_dir has - * 2 pages and is placed below swapper_pg_dir. - */ #define KERNEL_RAM_VADDR (PAGE_OFFSET + TEXT_OFFSET) -#if (KERNEL_RAM_VADDR & 0xfffff) != 0x80000 -#error KERNEL_RAM_VADDR must start at 0xXXX80000 +#if (TEXT_OFFSET & 0xf) != 0 +#error TEXT_OFFSET must be at least 16B aligned +#elif (PAGE_OFFSET & 0xfffff) != 0 +#error PAGE_OFFSET must be at least 2MB aligned +#elif TEXT_OFFSET > 0xfffff +#error TEXT_OFFSET must be less than 2MB #endif -#define SWAPPER_DIR_SIZE (3 * PAGE_SIZE) -#define IDMAP_DIR_SIZE (2 * PAGE_SIZE) - - .globl swapper_pg_dir - .equ swapper_pg_dir, KERNEL_RAM_VADDR - SWAPPER_DIR_SIZE - - .globl idmap_pg_dir - .equ idmap_pg_dir, swapper_pg_dir - IDMAP_DIR_SIZE - - .macro pgtbl, ttb0, ttb1, phys - add \ttb1, \phys, #TEXT_OFFSET - SWAPPER_DIR_SIZE - sub \ttb0, \ttb1, #IDMAP_DIR_SIZE + .macro pgtbl, ttb0, ttb1, virt_to_phys + ldr \ttb1, =swapper_pg_dir + ldr \ttb0, =idmap_pg_dir + add \ttb1, \ttb1, \virt_to_phys + add \ttb0, \ttb0, \virt_to_phys .endm #ifdef CONFIG_ARM64_64K_PAGES #define BLOCK_SHIFT PAGE_SHIFT #define BLOCK_SIZE PAGE_SIZE +#define TABLE_SHIFT PMD_SHIFT #else #define BLOCK_SHIFT SECTION_SHIFT #define BLOCK_SIZE SECTION_SIZE +#define TABLE_SHIFT PUD_SHIFT #endif #define KERNEL_START KERNEL_RAM_VADDR @@ -120,9 +115,9 @@ efi_head: b stext // branch to kernel start, magic .long 0 // reserved #endif - .quad TEXT_OFFSET // Image load offset from start of RAM - .quad 0 // reserved - .quad 0 // reserved + .quad _kernel_offset_le // Image load offset from start of RAM, little-endian + .quad _kernel_size_le // Effective size of kernel image, little-endian + .quad _kernel_flags_le // Informative flags, little-endian .quad 0 // reserved .quad 0 // reserved .quad 0 // reserved @@ -295,6 +290,23 @@ CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1 msr cnthctl_el2, x0 msr cntvoff_el2, xzr // Clear virtual offset +#ifdef CONFIG_ARM_GIC_V3 + /* GICv3 system register access */ + mrs x0, id_aa64pfr0_el1 + ubfx x0, x0, #24, #4 + cmp x0, #1 + b.ne 3f + + mrs_s x0, ICC_SRE_EL2 + orr x0, x0, #ICC_SRE_EL2_SRE // Set ICC_SRE_EL2.SRE==1 + orr x0, x0, #ICC_SRE_EL2_ENABLE // Set ICC_SRE_EL2.Enable==1 + msr_s ICC_SRE_EL2, x0 + isb // Make sure SRE is now set + msr_s ICH_HCR_EL2, xzr // Reset ICC_HCR_EL2 to defaults + +3: +#endif + /* Populate ID registers. */ mrs x0, midr_el1 mrs x1, mpidr_el1 @@ -413,7 +425,7 @@ ENTRY(secondary_startup) mov x23, x0 // x23=current cpu_table cbz x23, __error_p // invalid processor (x23=0)? - pgtbl x25, x26, x24 // x25=TTBR0, x26=TTBR1 + pgtbl x25, x26, x28 // x25=TTBR0, x26=TTBR1 ldr x12, [x23, #CPU_INFO_SETUP] add x12, x12, x28 // __virt_to_phys blr x12 // initialise processor @@ -455,8 +467,13 @@ ENDPROC(__enable_mmu) * x27 = *virtual* address to jump to upon completion * * other registers depend on the function called upon completion + * + * We align the entire function to the smallest power of two larger than it to + * ensure it fits within a single block map entry. Otherwise were PHYS_OFFSET + * close to the end of a 512MB or 1GB block we might require an additional + * table to map the entire function. */ - .align 6 + .align 4 __turn_mmu_on: msr sctlr_el1, x0 isb @@ -479,17 +496,38 @@ ENDPROC(__calc_phys_offset) .quad PAGE_OFFSET /* - * Macro to populate the PGD for the corresponding block entry in the next - * level (tbl) for the given virtual address. + * Macro to create a table entry to the next page. + * + * tbl: page table address + * virt: virtual address + * shift: #imm page table shift + * ptrs: #imm pointers per table page + * + * Preserves: virt + * Corrupts: 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 + orr \tmp2, \tmp2, #PMD_TYPE_TABLE // address of next table and entry type + 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. * - * Preserves: pgd, tbl, virt + * Preserves: tbl, next, virt * Corrupts: tmp1, tmp2 */ - .macro create_pgd_entry, pgd, tbl, virt, tmp1, tmp2 - lsr \tmp1, \virt, #PGDIR_SHIFT - and \tmp1, \tmp1, #PTRS_PER_PGD - 1 // PGD index - orr \tmp2, \tbl, #3 // PGD entry table type - str \tmp2, [\pgd, \tmp1, lsl #3] + .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, TABLE_SHIFT, PTRS_PER_PTE, \tmp1, \tmp2 +#endif .endm /* @@ -522,7 +560,7 @@ ENDPROC(__calc_phys_offset) * - pgd entry for fixed mappings (TTBR1) */ __create_page_tables: - pgtbl x25, x26, x24 // idmap_pg_dir and swapper_pg_dir addresses + pgtbl x25, x26, x28 // idmap_pg_dir and swapper_pg_dir addresses mov x27, lr /* @@ -550,10 +588,10 @@ __create_page_tables: /* * Create the identity mapping. */ - add x0, x25, #PAGE_SIZE // section table address + mov x0, x25 // idmap_pg_dir ldr x3, =KERNEL_START add x3, x3, x28 // __pa(KERNEL_START) - create_pgd_entry x25, x0, x3, x5, x6 + create_pgd_entry x0, x3, x5, x6 ldr x6, =KERNEL_END mov x5, x3 // __pa(KERNEL_START) add x6, x6, x28 // __pa(KERNEL_END) @@ -562,9 +600,9 @@ __create_page_tables: /* * Map the kernel image (starting with PHYS_OFFSET). */ - add x0, x26, #PAGE_SIZE // section table address + mov x0, x26 // swapper_pg_dir mov x5, #PAGE_OFFSET - create_pgd_entry x26, x0, x5, x3, x6 + create_pgd_entry x0, x5, x3, x6 ldr x6, =KERNEL_END mov x3, x24 // phys offset create_block_map x0, x7, x3, x5, x6 @@ -586,13 +624,6 @@ __create_page_tables: create_block_map x0, x7, x3, x5, x6 1: /* - * Create the pgd entry for the fixed mappings. - */ - ldr x5, =FIXADDR_TOP // Fixed mapping virtual address - add x0, x26, #2 * PAGE_SIZE // section table address - create_pgd_entry x26, x0, x5, x6, x7 - - /* * Since the page tables have been populated with non-cacheable * accesses (MMU disabled), invalidate the idmap and swapper page * tables again to remove any speculatively loaded cache lines. @@ -611,7 +642,7 @@ ENDPROC(__create_page_tables) __switch_data: .quad __mmap_switched .quad __bss_start // x6 - .quad _end // x7 + .quad __bss_stop // x7 .quad processor_id // x4 .quad __fdt_pointer // x5 .quad memstart_addr // x6 |
