1 // SPDX-License-Identifier: GPL-2.0
2 /* memory.c: Prom routine for acquiring various bits of information
3 * about RAM on the machine, both virtual and physical.
4 *
5 * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
6 * Copyright (C) 1997 Michael A. Griffith (grif@acm.org)
7 */
8
9 #include <linux/kernel.h>
10 #include <linux/sort.h>
11 #include <linux/init.h>
12
13 #include <asm/openprom.h>
14 #include <asm/oplib.h>
15 #include <asm/page.h>
16
prom_meminit_v0(void)17 static int __init prom_meminit_v0(void)
18 {
19 struct linux_mlist_v0 *p;
20 int index;
21
22 index = 0;
23 for (p = *(romvec->pv_v0mem.v0_available); p; p = p->theres_more) {
24 sp_banks[index].base_addr = (unsigned long) p->start_adr;
25 sp_banks[index].num_bytes = p->num_bytes;
26 index++;
27 }
28
29 return index;
30 }
31
prom_meminit_v2(void)32 static int __init prom_meminit_v2(void)
33 {
34 struct linux_prom_registers reg[64];
35 phandle node;
36 int size, num_ents, i;
37
38 node = prom_searchsiblings(prom_getchild(prom_root_node), "memory");
39 size = prom_getproperty(node, "available", (char *) reg, sizeof(reg));
40 num_ents = size / sizeof(struct linux_prom_registers);
41
42 for (i = 0; i < num_ents; i++) {
43 sp_banks[i].base_addr = reg[i].phys_addr;
44 sp_banks[i].num_bytes = reg[i].reg_size;
45 }
46
47 return num_ents;
48 }
49
sp_banks_cmp(const void * a,const void * b)50 static int sp_banks_cmp(const void *a, const void *b)
51 {
52 const struct sparc_phys_banks *x = a, *y = b;
53
54 if (x->base_addr > y->base_addr)
55 return 1;
56 if (x->base_addr < y->base_addr)
57 return -1;
58 return 0;
59 }
60
61 /* Initialize the memory lists based upon the prom version. */
prom_meminit(void)62 void __init prom_meminit(void)
63 {
64 int i, num_ents = 0;
65
66 switch (prom_vers) {
67 case PROM_V0:
68 num_ents = prom_meminit_v0();
69 break;
70
71 case PROM_V2:
72 case PROM_V3:
73 num_ents = prom_meminit_v2();
74 break;
75
76 default:
77 break;
78 }
79 sort(sp_banks, num_ents, sizeof(struct sparc_phys_banks),
80 sp_banks_cmp, NULL);
81
82 /* Sentinel. */
83 sp_banks[num_ents].base_addr = 0xdeadbeef;
84 sp_banks[num_ents].num_bytes = 0;
85
86 for (i = 0; i < num_ents; i++)
87 sp_banks[i].num_bytes &= PAGE_MASK;
88 }
89