xref: /openbmc/linux/arch/sparc/prom/memory.c (revision 588b48ca)
1 /* memory.c: Prom routine for acquiring various bits of information
2  *           about RAM on the machine, both virtual and physical.
3  *
4  * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
5  * Copyright (C) 1997 Michael A. Griffith (grif@acm.org)
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/sort.h>
10 #include <linux/init.h>
11 
12 #include <asm/openprom.h>
13 #include <asm/oplib.h>
14 #include <asm/page.h>
15 
16 static int __init prom_meminit_v0(void)
17 {
18 	struct linux_mlist_v0 *p;
19 	int index;
20 
21 	index = 0;
22 	for (p = *(romvec->pv_v0mem.v0_available); p; p = p->theres_more) {
23 		sp_banks[index].base_addr = (unsigned long) p->start_adr;
24 		sp_banks[index].num_bytes = p->num_bytes;
25 		index++;
26 	}
27 
28 	return index;
29 }
30 
31 static int __init prom_meminit_v2(void)
32 {
33 	struct linux_prom_registers reg[64];
34 	phandle node;
35 	int size, num_ents, i;
36 
37 	node = prom_searchsiblings(prom_getchild(prom_root_node), "memory");
38 	size = prom_getproperty(node, "available", (char *) reg, sizeof(reg));
39 	num_ents = size / sizeof(struct linux_prom_registers);
40 
41 	for (i = 0; i < num_ents; i++) {
42 		sp_banks[i].base_addr = reg[i].phys_addr;
43 		sp_banks[i].num_bytes = reg[i].reg_size;
44 	}
45 
46 	return num_ents;
47 }
48 
49 static int sp_banks_cmp(const void *a, const void *b)
50 {
51 	const struct sparc_phys_banks *x = a, *y = b;
52 
53 	if (x->base_addr > y->base_addr)
54 		return 1;
55 	if (x->base_addr < y->base_addr)
56 		return -1;
57 	return 0;
58 }
59 
60 /* Initialize the memory lists based upon the prom version. */
61 void __init prom_meminit(void)
62 {
63 	int i, num_ents = 0;
64 
65 	switch (prom_vers) {
66 	case PROM_V0:
67 		num_ents = prom_meminit_v0();
68 		break;
69 
70 	case PROM_V2:
71 	case PROM_V3:
72 		num_ents = prom_meminit_v2();
73 		break;
74 
75 	default:
76 		break;
77 	}
78 	sort(sp_banks, num_ents, sizeof(struct sparc_phys_banks),
79 	     sp_banks_cmp, NULL);
80 
81 	/* Sentinel.  */
82 	sp_banks[num_ents].base_addr = 0xdeadbeef;
83 	sp_banks[num_ents].num_bytes = 0;
84 
85 	for (i = 0; i < num_ents; i++)
86 		sp_banks[i].num_bytes &= PAGE_MASK;
87 }
88