xref: /linux/arch/x86/include/asm/sparsemem.h (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
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_PHYSMEM_BITS		2^n: max size of physical address space
14  *
15  */
16 
17 #ifdef CONFIG_X86_32
18 # ifdef CONFIG_X86_PAE
19 #  define SECTION_SIZE_BITS	29
20 #  define MAX_PHYSMEM_BITS	36
21 # else
22 #  define SECTION_SIZE_BITS	26
23 #  define MAX_PHYSMEM_BITS	32
24 # endif
25 #else /* CONFIG_X86_32 */
26 # define SECTION_SIZE_BITS	27 /* matt - 128 is convenient right now */
27 # define MAX_PHYSMEM_BITS	(pgtable_l5_enabled() ? 52 : 46)
28 #endif
29 
30 #endif /* CONFIG_SPARSEMEM */
31 
32 #ifndef __ASSEMBLY__
33 #ifdef CONFIG_NUMA_KEEP_MEMINFO
34 extern int phys_to_target_node(phys_addr_t start);
35 #define phys_to_target_node phys_to_target_node
36 extern int memory_add_physaddr_to_nid(u64 start);
37 #define memory_add_physaddr_to_nid memory_add_physaddr_to_nid
38 #endif
39 #endif /* __ASSEMBLY__ */
40 
41 #endif /* _ASM_X86_SPARSEMEM_H */
42