| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef _ASM_X86_SPARSEMEM_H |
| 3 | #define _ASM_X86_SPARSEMEM_H |
| 4 | |
| 5 | #ifdef CONFIG_SPARSEMEM |
| 6 | /* |
| 7 | * generic non-linear memory support: |
| 8 | * |
| 9 | * 1) we will not split memory into more chunks than will fit into the flags |
| 10 | * field of the struct page |
| 11 | * |
| 12 | * SECTION_SIZE_BITS 2^n: size of each section |
| 13 | * MAX_PHYSADDR_BITS 2^n: max size of physical address space |
| 14 | * MAX_PHYSMEM_BITS 2^n: how much memory we can have in that space |
| 15 | * |
| 16 | */ |
| 17 | |
| 18 | #ifdef CONFIG_X86_32 |
| 19 | # ifdef CONFIG_X86_PAE |
| 20 | # define SECTION_SIZE_BITS 29 |
| 21 | # define MAX_PHYSADDR_BITS 36 |
| 22 | # define MAX_PHYSMEM_BITS 36 |
| 23 | # else |
| 24 | # define SECTION_SIZE_BITS 26 |
| 25 | # define MAX_PHYSADDR_BITS 32 |
| 26 | # define MAX_PHYSMEM_BITS 32 |
| 27 | # endif |
| 28 | #else /* CONFIG_X86_32 */ |
| 29 | # define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */ |
| 30 | # define MAX_PHYSADDR_BITS (pgtable_l5_enabled() ? 52 : 44) |
| 31 | # define MAX_PHYSMEM_BITS (pgtable_l5_enabled() ? 52 : 46) |
| 32 | #endif |
| 33 | |
| 34 | #endif /* CONFIG_SPARSEMEM */ |
| 35 | #endif /* _ASM_X86_SPARSEMEM_H */ |