aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/mips-boards/generic/memory.c
blob: dc272c1882337167a0350d87afc978702b1c0f0a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/*
 * Carsten Langgaard, carstenl@mips.com
 * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
 *
 *  This program is free software; you can distribute it and/or modify it
 *  under the terms of the GNU General Public License (Version 2) as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
 *
 * PROM library functions for acquiring/using memory descriptors given to
 * us from the YAMON.
 */
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/pfn.h>
#include <linux/string.h>

#include <asm/bootinfo.h>
#include <asm/page.h>
#include <asm/sections.h>

#include <asm/mips-boards/prom.h>

/*#define DEBUG*/

enum yamon_memtypes {
	yamon_dontuse,
	yamon_prom,
	yamon_free,
};
struct prom_pmemblock mdesc[PROM_MAX_PMEMBLOCKS];

#ifdef DEBUG
static char *mtypes[3] = {
	"Dont use memory",
	"YAMON PROM memory",
	"Free memmory",
};
#endif

/* determined physical memory size, not overridden by command line args  */
unsigned long physical_memsize = 0L;

struct prom_pmemblock * __init prom_getmdesc(void)
{
	char *memsize_str;
	unsigned int memsize;
	char cmdline[CL_SIZE], *ptr;

	/* otherwise look in the environment */
	memsize_str = prom_getenv("memsize");
	if (!memsize_str) {
		printk(KERN_WARNING
		       "memsize not set in boot prom, set to default (32Mb)\n");
		physical_memsize = 0x02000000;
	} else {
#ifdef DEBUG
		pr_debug("prom_memsize = %s\n", memsize_str);
#endif
		physical_memsize = simple_strtol(memsize_str, NULL, 0);
	}

#ifdef CONFIG_CPU_BIG_ENDIAN
	/* SOC-it swaps, or perhaps doesn't swap, when DMA'ing the last
	   word of physical memory */
	physical_memsize -= PAGE_SIZE;
#endif

	/* Check the command line for a memsize directive that overrides
	   the physical/default amount */
	strcpy(cmdline, arcs_cmdline);
	ptr = strstr(cmdline, "memsize=");
	if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
		ptr = strstr(ptr, " memsize=");

	if (ptr)
		memsize = memparse(ptr + 8, &ptr);
	else
		memsize = physical_memsize;

	memset(mdesc, 0, sizeof(mdesc));

	mdesc[0].type = yamon_dontuse;
	mdesc[0].base = 0x00000000;
	mdesc[0].size = 0x00001000;

	mdesc[1].type = yamon_prom;
	mdesc[1].base = 0x00001000;
	mdesc[1].size = 0x000ef000;

#ifdef CONFIG_MIPS_MALTA
	/*
	 * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the
	 * south bridge and PCI access always forwarded to the ISA Bus and
	 * BIOSCS# is always generated.
	 * This mean that this area can't be used as DMA memory for PCI
	 * devices.
	 */
	mdesc[2].type = yamon_dontuse;
	mdesc[2].base = 0x000f0000;
	mdesc[2].size = 0x00010000;
#else
	mdesc[2].type = yamon_prom;
	mdesc[2].base = 0x000f0000;
	mdesc[2].size = 0x00010000;
#endif

	mdesc[3].type = yamon_dontuse;
	mdesc[3].base = 0x00100000;
	mdesc[3].size = CPHYSADDR(PFN_ALIGN((unsigned long)&_end)) - mdesc[3].base;

	mdesc[4].type = yamon_free;
	mdesc[4].base = CPHYSADDR(PFN_ALIGN(&_end));
	mdesc[4].size = memsize - mdesc[4].base;

	return &mdesc[0];
}

static int __init prom_memtype_classify(unsigned int type)
{
	switch (type) {
	case yamon_free:
		return BOOT_MEM_RAM;
	case yamon_prom:
		return BOOT_MEM_ROM_DATA;
	default:
		return BOOT_MEM_RESERVED;
	}
}

void __init prom_meminit(void)
{
	struct prom_pmemblock *p;

#ifdef DEBUG
	pr_debug("YAMON MEMORY DESCRIPTOR dump:\n");
	p = prom_getmdesc();
	while (p->size) {
		int i = 0;
		pr_debug("[%d,%p]: base<%08lx> size<%08lx> type<%s>\n",
			 i, p, p->base, p->size, mtypes[p->type]);
		p++;
		i++;
	}
#endif
	p = prom_getmdesc();

	while (p->size) {
		long type;
		unsigned long base, size;

		type = prom_memtype_classify(p->type);
		base = p->base;
		size = p->size;

		add_memory_region(base, size, type);
                p++;
	}
}

void __init prom_free_prom_memory(void)
{
	unsigned long addr;
	int i;

	for (i = 0; i < boot_mem_map.nr_map; i++) {
		if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
			continue;

		addr = boot_mem_map.map[i].addr;
		free_init_pages("prom memory",
				addr, addr + boot_mem_map.map[i].size);
	}
}