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
17static 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
32static 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
50static 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. */
62void __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