2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * PROM library functions for acquiring/using memory descriptors given to
9 * Copyright (C) 1999,2000,2012 MIPS Technologies, Inc.
10 * All rights reserved.
11 * Authors: Carsten Langgaard <carstenl@mips.com>
12 * Steven J. Hill <sjhill@mips.com>
14 #include <linux/init.h>
15 #include <linux/bootmem.h>
16 #include <linux/string.h>
18 #include <asm/bootinfo.h>
21 #include <asm/sections.h>
22 #include <asm/fw/fw.h>
24 static fw_memblock_t mdesc[FW_MAX_MEMBLOCKS];
26 /* determined physical memory size, not overridden by command line args */
27 unsigned long physical_memsize = 0L;
29 fw_memblock_t * __init fw_getmdesc(int eva)
31 char *memsize_str, *ememsize_str = NULL, *ptr;
32 unsigned long memsize = 0, ememsize = 0;
33 static char cmdline[COMMAND_LINE_SIZE] __initdata;
36 /* otherwise look in the environment */
38 memsize_str = fw_getenv("memsize");
40 tmp = kstrtoul(memsize_str, 0, &memsize);
42 pr_warn("Failed to read the 'memsize' env variable.\n");
45 /* Look for ememsize for EVA */
46 ememsize_str = fw_getenv("ememsize");
48 tmp = kstrtoul(ememsize_str, 0, &ememsize);
50 pr_warn("Failed to read the 'ememsize' env variable.\n");
53 if (!memsize && !ememsize) {
54 pr_warn("memsize not set in YAMON, set to default (32Mb)\n");
55 physical_memsize = 0x02000000;
57 /* If ememsize is set, then set physical_memsize to that */
58 physical_memsize = ememsize ? : memsize;
61 #ifdef CONFIG_CPU_BIG_ENDIAN
62 /* SOC-it swaps, or perhaps doesn't swap, when DMA'ing the last
63 word of physical memory */
64 physical_memsize -= PAGE_SIZE;
67 /* Check the command line for a memsize directive that overrides
68 the physical/default amount */
69 strcpy(cmdline, arcs_cmdline);
70 ptr = strstr(cmdline, "memsize=");
71 if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
72 ptr = strstr(ptr, " memsize=");
73 /* And now look for ememsize */
75 ptr = strstr(cmdline, "ememsize=");
76 if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' '))
77 ptr = strstr(ptr, " ememsize=");
81 memsize = memparse(ptr + 8 + (eva ? 1 : 0), &ptr);
83 memsize = physical_memsize;
85 /* Last 64K for HIGHMEM arithmetics */
86 if (memsize > 0x7fff0000)
89 memset(mdesc, 0, sizeof(mdesc));
91 mdesc[0].type = fw_dontuse;
92 mdesc[0].base = PHYS_OFFSET;
93 mdesc[0].size = 0x00001000;
95 mdesc[1].type = fw_code;
96 mdesc[1].base = mdesc[0].base + 0x00001000UL;
97 mdesc[1].size = 0x000ef000;
100 * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the
101 * south bridge and PCI access always forwarded to the ISA Bus and
102 * BIOSCS# is always generated.
103 * This mean that this area can't be used as DMA memory for PCI
106 mdesc[2].type = fw_dontuse;
107 mdesc[2].base = mdesc[0].base + 0x000f0000UL;
108 mdesc[2].size = 0x00010000;
110 mdesc[3].type = fw_dontuse;
111 mdesc[3].base = mdesc[0].base + 0x00100000UL;
112 mdesc[3].size = CPHYSADDR(PFN_ALIGN((unsigned long)&_end)) -
115 mdesc[4].type = fw_free;
116 mdesc[4].base = mdesc[0].base + CPHYSADDR(PFN_ALIGN(&_end));
117 mdesc[4].size = memsize - CPHYSADDR(mdesc[4].base);
122 static void free_init_pages_eva_malta(void *begin, void *end)
124 free_init_pages("unused kernel", __pa_symbol((unsigned long *)begin),
125 __pa_symbol((unsigned long *)end));
128 static int __init fw_memtype_classify(unsigned int type)
134 return BOOT_MEM_ROM_DATA;
136 return BOOT_MEM_RESERVED;
140 void __init fw_meminit(void)
144 p = fw_getmdesc(config_enabled(CONFIG_EVA));
145 free_init_pages_eva = (config_enabled(CONFIG_EVA) ?
146 free_init_pages_eva_malta : NULL);
150 unsigned long base, size;
152 type = fw_memtype_classify(p->type);
156 add_memory_region(base, size, type);
161 void __init prom_free_prom_memory(void)
166 for (i = 0; i < boot_mem_map.nr_map; i++) {
167 if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
170 addr = boot_mem_map.map[i].addr;
171 free_init_pages("YAMON memory",
172 addr, addr + boot_mem_map.map[i].size);
176 unsigned platform_maar_init(unsigned num_pairs)
178 phys_addr_t mem_end = (physical_memsize & ~0xffffull) - 1;
179 struct maar_config cfg[] = {
180 /* DRAM preceding I/O */
181 { 0x00000000, 0x0fffffff, MIPS_MAAR_S },
183 /* DRAM following I/O */
184 { 0x20000000, mem_end, MIPS_MAAR_S },
186 /* DRAM alias in upper half of physical */
187 { 0x80000000, 0x80000000 + mem_end, MIPS_MAAR_S },
189 unsigned i, num_cfg = ARRAY_SIZE(cfg);
191 /* If DRAM fits before I/O, drop the region following it */
192 if (physical_memsize <= 0x10000000) {
194 for (i = 1; i < num_cfg; i++)
198 return maar_config(cfg, num_cfg, num_pairs);
201 phys_addr_t mips_cdmm_phys_base(void)
203 /* This address is "typically unused" */