1 /*
2 * Copyright IBM Corp. 2008, 2009
3 *
4 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
5 */
6
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/memblock.h>
10 #include <linux/init.h>
11 #include <linux/debugfs.h>
12 #include <linux/seq_file.h>
13 #include <asm/ipl.h>
14 #include <asm/sclp.h>
15 #include <asm/setup.h>
16
17 #define ADDR2G (1ULL << 31)
18
19 #define CHUNK_READ_WRITE 0
20 #define CHUNK_READ_ONLY 1
21
memblock_physmem_add(phys_addr_t start,phys_addr_t size)22 static inline void memblock_physmem_add(phys_addr_t start, phys_addr_t size)
23 {
24 memblock_add_range(&memblock.memory, start, size, 0, 0);
25 memblock_add_range(&memblock.physmem, start, size, 0, 0);
26 }
27
detect_memory_memblock(void)28 void __init detect_memory_memblock(void)
29 {
30 unsigned long long memsize, rnmax, rzm;
31 unsigned long addr, size;
32 int type;
33
34 rzm = sclp_get_rzm();
35 rnmax = sclp_get_rnmax();
36 memsize = rzm * rnmax;
37 if (!rzm)
38 rzm = 1ULL << 17;
39 if (IS_ENABLED(CONFIG_32BIT)) {
40 rzm = min(ADDR2G, rzm);
41 memsize = min(ADDR2G, memsize);
42 }
43 max_physmem_end = memsize;
44 addr = 0;
45 /* keep memblock lists close to the kernel */
46 memblock_set_bottom_up(true);
47 do {
48 size = 0;
49 type = tprot(addr);
50 do {
51 size += rzm;
52 if (max_physmem_end && addr + size >= max_physmem_end)
53 break;
54 } while (type == tprot(addr + size));
55 if (type == CHUNK_READ_WRITE || type == CHUNK_READ_ONLY) {
56 if (max_physmem_end && (addr + size > max_physmem_end))
57 size = max_physmem_end - addr;
58 memblock_physmem_add(addr, size);
59 }
60 addr += size;
61 } while (addr < max_physmem_end);
62 memblock_set_bottom_up(false);
63 if (!max_physmem_end)
64 max_physmem_end = memblock_end_of_DRAM();
65 }
66