| /* |
| * Kernel page table mapping |
| * |
| * Copyright (C) 2015 ARM Ltd. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #ifndef __ASM_KERNEL_PGTABLE_H |
| #define __ASM_KERNEL_PGTABLE_H |
| |
| |
| /* |
| * The linear mapping and the start of memory are both 2M aligned (per |
| * the arm64 booting.txt requirements). Hence we can use section mapping |
| * with 4K (section size = 2M) but not with 16K (section size = 32M) or |
| * 64K (section size = 512M). |
| */ |
| #ifdef CONFIG_ARM64_4K_PAGES |
| #define ARM64_SWAPPER_USES_SECTION_MAPS 1 |
| #else |
| #define ARM64_SWAPPER_USES_SECTION_MAPS 0 |
| #endif |
| |
| /* |
| * The idmap and swapper page tables need some space reserved in the kernel |
| * image. Both require pgd, pud (4 levels only) and pmd tables to (section) |
| * map the kernel. With the 64K page configuration, swapper and idmap need to |
| * map to pte level. The swapper also maps the FDT (see __create_page_tables |
| * for more information). Note that the number of ID map translation levels |
| * could be increased on the fly if system RAM is out of reach for the default |
| * VA range, so pages required to map highest possible PA are reserved in all |
| * cases. |
| */ |
| #if ARM64_SWAPPER_USES_SECTION_MAPS |
| #define SWAPPER_PGTABLE_LEVELS (CONFIG_PGTABLE_LEVELS - 1) |
| #define IDMAP_PGTABLE_LEVELS (ARM64_HW_PGTABLE_LEVELS(PHYS_MASK_SHIFT) - 1) |
| #else |
| #define SWAPPER_PGTABLE_LEVELS (CONFIG_PGTABLE_LEVELS) |
| #define IDMAP_PGTABLE_LEVELS (ARM64_HW_PGTABLE_LEVELS(PHYS_MASK_SHIFT)) |
| #endif |
| |
| #define SWAPPER_DIR_SIZE (SWAPPER_PGTABLE_LEVELS * PAGE_SIZE) |
| #define IDMAP_DIR_SIZE (IDMAP_PGTABLE_LEVELS * PAGE_SIZE) |
| |
| /* Initial memory map size */ |
| #if ARM64_SWAPPER_USES_SECTION_MAPS |
| #define SWAPPER_BLOCK_SHIFT SECTION_SHIFT |
| #define SWAPPER_BLOCK_SIZE SECTION_SIZE |
| #define SWAPPER_TABLE_SHIFT PUD_SHIFT |
| #else |
| #define SWAPPER_BLOCK_SHIFT PAGE_SHIFT |
| #define SWAPPER_BLOCK_SIZE PAGE_SIZE |
| #define SWAPPER_TABLE_SHIFT PMD_SHIFT |
| #endif |
| |
| /* The size of the initial kernel direct mapping */ |
| #define SWAPPER_INIT_MAP_SIZE (_AC(1, UL) << SWAPPER_TABLE_SHIFT) |
| |
| /* |
| * Initial memory map attributes. |
| */ |
| #define SWAPPER_PTE_FLAGS (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED) |
| #define SWAPPER_PMD_FLAGS (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S) |
| |
| #if ARM64_SWAPPER_USES_SECTION_MAPS |
| #define SWAPPER_MM_MMUFLAGS (PMD_ATTRINDX(MT_NORMAL) | SWAPPER_PMD_FLAGS) |
| #else |
| #define SWAPPER_MM_MMUFLAGS (PTE_ATTRINDX(MT_NORMAL) | SWAPPER_PTE_FLAGS) |
| #endif |
| |
| /* |
| * To make optimal use of block mappings when laying out the linear |
| * mapping, round down the base of physical memory to a size that can |
| * be mapped efficiently, i.e., either PUD_SIZE (4k granule) or PMD_SIZE |
| * (64k granule), or a multiple that can be mapped using contiguous bits |
| * in the page tables: 32 * PMD_SIZE (16k granule) |
| */ |
| #ifdef CONFIG_ARM64_64K_PAGES |
| #define ARM64_MEMSTART_ALIGN SZ_512M |
| #else |
| #define ARM64_MEMSTART_ALIGN SZ_1G |
| #endif |
| |
| #endif /* __ASM_KERNEL_PGTABLE_H */ |
