1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2008, 2009
4 *
5 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
6 */
7
8 #include <linux/kernel.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 CHUNK_READ_WRITE 0
18 #define CHUNK_READ_ONLY 1
19
memblock_physmem_add(phys_addr_t start,phys_addr_t size)20 static inline void memblock_physmem_add(phys_addr_t start, phys_addr_t size)
21 {
22 memblock_dbg("memblock_physmem_add: [%#016llx-%#016llx]\n",
23 start, start + size - 1);
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 memsize, rnmax, rzm, addr, size;
31 int type;
32
33 rzm = sclp.rzm;
34 rnmax = sclp.rnmax;
35 memsize = rzm * rnmax;
36 if (!rzm)
37 rzm = 1UL << 17;
38 max_physmem_end = memsize;
39 addr = 0;
40 /* keep memblock lists close to the kernel */
41 memblock_set_bottom_up(true);
42 do {
43 size = 0;
44 /* assume lowcore is writable */
45 type = addr ? tprot(addr) : CHUNK_READ_WRITE;
46 do {
47 size += rzm;
48 if (max_physmem_end && addr + size >= max_physmem_end)
49 break;
50 } while (type == tprot(addr + size));
51 if (type == CHUNK_READ_WRITE || type == CHUNK_READ_ONLY) {
52 if (max_physmem_end && (addr + size > max_physmem_end))
53 size = max_physmem_end - addr;
54 memblock_physmem_add(addr, size);
55 }
56 addr += size;
57 } while (addr < max_physmem_end);
58 memblock_set_bottom_up(false);
59 if (!max_physmem_end)
60 max_physmem_end = memblock_end_of_DRAM();
61 memblock_dump_all();
62 }
63
