1 /*
2 * Carsten Langgaard, carstenl@mips.com
3 * Copyright (C) 1999,2000 MIPS Technologies, Inc. All rights reserved.
4 *
5 * This program is free software; you can distribute it and/or modify it
6 * under the terms of the GNU General Public License (Version 2) as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
17 *
18 * PROM library functions for acquiring/using memory descriptors given to
19 * us from the YAMON.
20 */
21 #include <linux/init.h>
22 #include <linux/mm.h>
23 #include <linux/bootmem.h>
24 #include <linux/pfn.h>
25 #include <linux/string.h>
26
27 #include <asm/bootinfo.h>
28 #include <asm/page.h>
29 #include <asm/sections.h>
30
31 #include <asm/mips-boards/prom.h>
32
33 /*#define DEBUG*/
34
35 enum yamon_memtypes {
36 yamon_dontuse,
37 yamon_prom,
38 yamon_free,
39 };
40 static struct prom_pmemblock mdesc[PROM_MAX_PMEMBLOCKS];
41
42 #ifdef DEBUG
43 static char *mtypes[3] = {
44 "Dont use memory",
45 "YAMON PROM memory",
46 "Free memory",
47 };
48 #endif
49
50 /* determined physical memory size, not overridden by command line args */
51 unsigned long physical_memsize = 0L;
52
prom_getmdesc(void)53 static struct prom_pmemblock * __init prom_getmdesc(void)
54 {
55 char *memsize_str;
56 unsigned int memsize;
57 char *ptr;
58 static char cmdline[COMMAND_LINE_SIZE] __initdata;
59
60 /* otherwise look in the environment */
61 memsize_str = prom_getenv("memsize");
62 if (!memsize_str) {
63 printk(KERN_WARNING
64 "memsize not set in boot prom, set to default (32Mb)\n");
65 physical_memsize = 0x02000000;
66 } else {
67 #ifdef DEBUG
68 pr_debug("prom_memsize = %s\n", memsize_str);
69 #endif
70 physical_memsize = simple_strtol(memsize_str, NULL, 0);
71 }
72
73 #ifdef CONFIG_CPU_BIG_ENDIAN
74 /* SOC-it swaps, or perhaps doesn't swap, when DMA'ing the last
75 word of physical memory */
76 physical_memsize -= PAGE_SIZE;
77 #endif
78
79 /* Check the command line for a memsize directive that overrides
80 the physical/default amount */
81 strcpy(cmdline, arcs_cmdline);
82 ptr = strstr(cmdline, "memsize=");
83 if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
84 ptr = strstr(ptr, " memsize=");
85
86 if (ptr)
87 memsize = memparse(ptr + 8, &ptr);
88 else
89 memsize = physical_memsize;
90
91 memset(mdesc, 0, sizeof(mdesc));
92
93 mdesc[0].type = yamon_dontuse;
94 mdesc[0].base = 0x00000000;
95 mdesc[0].size = 0x00001000;
96
97 mdesc[1].type = yamon_prom;
98 mdesc[1].base = 0x00001000;
99 mdesc[1].size = 0x000ef000;
100
101 /*
102 * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the
103 * south bridge and PCI access always forwarded to the ISA Bus and
104 * BIOSCS# is always generated.
105 * This mean that this area can't be used as DMA memory for PCI
106 * devices.
107 */
108 mdesc[2].type = yamon_dontuse;
109 mdesc[2].base = 0x000f0000;
110 mdesc[2].size = 0x00010000;
111
112 mdesc[3].type = yamon_dontuse;
113 mdesc[3].base = 0x00100000;
114 mdesc[3].size = CPHYSADDR(PFN_ALIGN((unsigned long)&_end)) - mdesc[3].base;
115
116 mdesc[4].type = yamon_free;
117 mdesc[4].base = CPHYSADDR(PFN_ALIGN(&_end));
118 mdesc[4].size = memsize - mdesc[4].base;
119
120 return &mdesc[0];
121 }
122
prom_memtype_classify(unsigned int type)123 static int __init prom_memtype_classify(unsigned int type)
124 {
125 switch (type) {
126 case yamon_free:
127 return BOOT_MEM_RAM;
128 case yamon_prom:
129 return BOOT_MEM_ROM_DATA;
130 default:
131 return BOOT_MEM_RESERVED;
132 }
133 }
134
prom_meminit(void)135 void __init prom_meminit(void)
136 {
137 struct prom_pmemblock *p;
138
139 #ifdef DEBUG
140 pr_debug("YAMON MEMORY DESCRIPTOR dump:\n");
141 p = prom_getmdesc();
142 while (p->size) {
143 int i = 0;
144 pr_debug("[%d,%p]: base<%08lx> size<%08lx> type<%s>\n",
145 i, p, p->base, p->size, mtypes[p->type]);
146 p++;
147 i++;
148 }
149 #endif
150 p = prom_getmdesc();
151
152 while (p->size) {
153 long type;
154 unsigned long base, size;
155
156 type = prom_memtype_classify(p->type);
157 base = p->base;
158 size = p->size;
159
160 add_memory_region(base, size, type);
161 p++;
162 }
163 }
164
prom_free_prom_memory(void)165 void __init prom_free_prom_memory(void)
166 {
167 unsigned long addr;
168 int i;
169
170 for (i = 0; i < boot_mem_map.nr_map; i++) {
171 if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
172 continue;
173
174 addr = boot_mem_map.map[i].addr;
175 free_init_pages("prom memory",
176 addr, addr + boot_mem_map.map[i].size);
177 }
178 }
179