linux/arch/arm64/include/asm/kernel-pgtable.h

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/*
* 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 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 3 pages are reserved in all cases.
*/
#ifdef CONFIG_ARM64_64K_PAGES
#define SWAPPER_PGTABLE_LEVELS (CONFIG_PGTABLE_LEVELS)
#else
#define SWAPPER_PGTABLE_LEVELS (CONFIG_PGTABLE_LEVELS - 1)
#endif
#define SWAPPER_DIR_SIZE (SWAPPER_PGTABLE_LEVELS * PAGE_SIZE)
#define IDMAP_DIR_SIZE (3 * PAGE_SIZE)
/* Initial memory map size */
#ifdef CONFIG_ARM64_64K_PAGES
#define SWAPPER_BLOCK_SHIFT PAGE_SHIFT
#define SWAPPER_BLOCK_SIZE PAGE_SIZE
#define SWAPPER_TABLE_SHIFT PMD_SHIFT
#else
#define SWAPPER_BLOCK_SHIFT SECTION_SHIFT
#define SWAPPER_BLOCK_SIZE SECTION_SIZE
#define SWAPPER_TABLE_SHIFT PUD_SHIFT
#endif
/*
* 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)
#ifdef CONFIG_ARM64_64K_PAGES
#define SWAPPER_MM_MMUFLAGS (PTE_ATTRINDX(MT_NORMAL) | SWAPPER_PTE_FLAGS)
#else
#define SWAPPER_MM_MMUFLAGS (PMD_ATTRINDX(MT_NORMAL) | SWAPPER_PMD_FLAGS)
#endif
#endif /* __ASM_KERNEL_PGTABLE_H */