arch/arm64/include/asm/pgtable-2level-hwdef.h

   1 /*
   2  * Copyright (C) 2012 ARM Ltd.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  */
  16 #ifndef __ASM_PGTABLE_2LEVEL_HWDEF_H
  17 #define __ASM_PGTABLE_2LEVEL_HWDEF_H
  18
  19 /*
  20  * With LPAE and 64KB pages, there are 2 levels of page tables. Each level has
  21  * 8192 entries of 8 bytes each, occupying a 64KB page. Levels 0 and 1 are not
  22  * used. The 2nd level table (PGD for Linux) can cover a range of 4TB, each
  23  * entry representing 512MB. The user and kernel address spaces are limited to
  24  * 512GB and therefore we only use 1024 entries in the PGD.
  25  */
  26 #define PTRS_PER_PTE            8192
  27 #define PTRS_PER_PGD            1024
  28
  29 /*
  30  * PGDIR_SHIFT determines the size a top-level page table entry can map.
  31  */
  32 #define PGDIR_SHIFT             29
  33 #define PGDIR_SIZE              (_AC(1, UL) << PGDIR_SHIFT)
  34 #define PGDIR_MASK              (~(PGDIR_SIZE-1))
  35
  36 /*
  37  * section address mask and size definitions.
  38  */
  39 #define SECTION_SHIFT           29
  40 #define SECTION_SIZE            (_AC(1, UL) << SECTION_SHIFT)
  41 #define SECTION_MASK            (~(SECTION_SIZE-1))
  42
  43 #endif