xref: /linux/arch/arm/include/asm/sparsemem.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 #ifndef ASMARM_SPARSEMEM_H
2 #define ASMARM_SPARSEMEM_H
3 
4 #include <asm/memory.h>
5 
6 /*
7  * Two definitions are required for sparsemem:
8  *
9  * MAX_PHYSMEM_BITS: The number of physical address bits required
10  *   to address the last byte of memory.
11  *
12  * SECTION_SIZE_BITS: The number of physical address bits to cover
13  *   the maximum amount of memory in a section.
14  *
15  * Eg, if you have 2 banks of up to 64MB at 0x80000000, 0x84000000,
16  * then MAX_PHYSMEM_BITS is 32, SECTION_SIZE_BITS is 26.
17  *
18  * Define these in your mach/memory.h.
19  */
20 #if !defined(SECTION_SIZE_BITS) || !defined(MAX_PHYSMEM_BITS)
21 #error Sparsemem is not supported on this platform
22 #endif
23 
24 #endif
25