| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _ASM_X86_SPARSEMEM_H |
| #define _ASM_X86_SPARSEMEM_H |
| |
| #ifdef CONFIG_SPARSEMEM |
| /* |
| * generic non-linear memory support: |
| * |
| * 1) we will not split memory into more chunks than will fit into the flags |
| * field of the struct page |
| * |
| * SECTION_SIZE_BITS 2^n: size of each section |
| * MAX_PHYSMEM_BITS 2^n: max size of physical address space |
| * |
| */ |
| |
| #ifdef CONFIG_X86_32 |
| # ifdef CONFIG_X86_PAE |
| # define SECTION_SIZE_BITS 29 |
| # define MAX_PHYSMEM_BITS 36 |
| # else |
| # define SECTION_SIZE_BITS 26 |
| # define MAX_PHYSMEM_BITS 32 |
| # endif |
| #else /* CONFIG_X86_32 */ |
| # define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */ |
| # define MAX_PHYSMEM_BITS (pgtable_l5_enabled() ? 52 : 46) |
| #endif |
| |
| #endif /* CONFIG_SPARSEMEM */ |
| #endif /* _ASM_X86_SPARSEMEM_H */ |
