arch/arm64/include/asm/sparsemem.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2012 ARM Ltd.
   4  */
   5 #ifndef __ASM_SPARSEMEM_H
   6 #define __ASM_SPARSEMEM_H
   7
   8 #define MAX_PHYSMEM_BITS        CONFIG_ARM64_PA_BITS
   9
  10 /*
  11  * Section size must be at least 512MB for 64K base
  12  * page size config. Otherwise it will be less than
  13  * MAX_PAGE_ORDER and the build process will fail.
  14  */
  15 #ifdef CONFIG_ARM64_64K_PAGES
  16 #define SECTION_SIZE_BITS 29
  17
  18 #else
  19
  20 /*
  21  * Section size must be at least 128MB for 4K base
  22  * page size config. Otherwise PMD based huge page
  23  * entries could not be created for vmemmap mappings.
  24  * 16K follows 4K for simplicity.
  25  */
  26 #define SECTION_SIZE_BITS 27
  27 #endif /* CONFIG_ARM64_64K_PAGES */
  28
  29 #endif