1 /* 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 4 * for more details. 5 * 6 * PROM library functions for acquiring/using memory descriptors given to 7 * us from the YAMON. 8 * 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> 13 */ 14 #include <linux/init.h> 15 #include <linux/bootmem.h> 16 #include <linux/string.h> 17 18 #include <asm/bootinfo.h> 19 #include <asm/maar.h> 20 #include <asm/sections.h> 21 #include <asm/fw/fw.h> 22 23 static fw_memblock_t mdesc[FW_MAX_MEMBLOCKS]; 24 25 /* determined physical memory size, not overridden by command line args */ 26 unsigned long physical_memsize = 0L; 27 28 fw_memblock_t * __init fw_getmdesc(int eva) 29 { 30 char *memsize_str, *ememsize_str = NULL, *ptr; 31 unsigned long memsize = 0, ememsize = 0; 32 static char cmdline[COMMAND_LINE_SIZE] __initdata; 33 int tmp; 34 35 /* otherwise look in the environment */ 36 37 memsize_str = fw_getenv("memsize"); 38 if (memsize_str) { 39 tmp = kstrtoul(memsize_str, 0, &memsize); 40 if (tmp) 41 pr_warn("Failed to read the 'memsize' env variable.\n"); 42 } 43 if (eva) { 44 /* Look for ememsize for EVA */ 45 ememsize_str = fw_getenv("ememsize"); 46 if (ememsize_str) { 47 tmp = kstrtoul(ememsize_str, 0, &ememsize); 48 if (tmp) 49 pr_warn("Failed to read the 'ememsize' env variable.\n"); 50 } 51 } 52 if (!memsize && !ememsize) { 53 pr_warn("memsize not set in YAMON, set to default (32Mb)\n"); 54 physical_memsize = 0x02000000; 55 } else { 56 /* If ememsize is set, then set physical_memsize to that */ 57 physical_memsize = ememsize ? : memsize; 58 } 59 60 #ifdef CONFIG_CPU_BIG_ENDIAN 61 /* SOC-it swaps, or perhaps doesn't swap, when DMA'ing the last 62 word of physical memory */ 63 physical_memsize -= PAGE_SIZE; 64 #endif 65 66 /* Check the command line for a memsize directive that overrides 67 the physical/default amount */ 68 strcpy(cmdline, arcs_cmdline); 69 ptr = strstr(cmdline, "memsize="); 70 if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' ')) 71 ptr = strstr(ptr, " memsize="); 72 /* And now look for ememsize */ 73 if (eva) { 74 ptr = strstr(cmdline, "ememsize="); 75 if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' ')) 76 ptr = strstr(ptr, " ememsize="); 77 } 78 79 if (ptr) 80 memsize = memparse(ptr + 8 + (eva ? 1 : 0), &ptr); 81 else 82 memsize = physical_memsize; 83 84 /* Last 64K for HIGHMEM arithmetics */ 85 if (memsize > 0x7fff0000) 86 memsize = 0x7fff0000; 87 88 memset(mdesc, 0, sizeof(mdesc)); 89 90 mdesc[0].type = fw_dontuse; 91 mdesc[0].base = PHYS_OFFSET; 92 mdesc[0].size = 0x00001000; 93 94 mdesc[1].type = fw_code; 95 mdesc[1].base = mdesc[0].base + 0x00001000UL; 96 mdesc[1].size = 0x000ef000; 97 98 /* 99 * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the 100 * south bridge and PCI access always forwarded to the ISA Bus and 101 * BIOSCS# is always generated. 102 * This mean that this area can't be used as DMA memory for PCI 103 * devices. 104 */ 105 mdesc[2].type = fw_dontuse; 106 mdesc[2].base = mdesc[0].base + 0x000f0000UL; 107 mdesc[2].size = 0x00010000; 108 109 mdesc[3].type = fw_dontuse; 110 mdesc[3].base = mdesc[0].base + 0x00100000UL; 111 mdesc[3].size = CPHYSADDR(PFN_ALIGN((unsigned long)&_end)) - 112 0x00100000UL; 113 114 mdesc[4].type = fw_free; 115 mdesc[4].base = mdesc[0].base + CPHYSADDR(PFN_ALIGN(&_end)); 116 mdesc[4].size = memsize - CPHYSADDR(mdesc[4].base); 117 118 return &mdesc[0]; 119 } 120 121 static void free_init_pages_eva_malta(void *begin, void *end) 122 { 123 free_init_pages("unused kernel", __pa_symbol((unsigned long *)begin), 124 __pa_symbol((unsigned long *)end)); 125 } 126 127 static int __init fw_memtype_classify(unsigned int type) 128 { 129 switch (type) { 130 case fw_free: 131 return BOOT_MEM_RAM; 132 case fw_code: 133 return BOOT_MEM_ROM_DATA; 134 default: 135 return BOOT_MEM_RESERVED; 136 } 137 } 138 139 void __init fw_meminit(void) 140 { 141 fw_memblock_t *p; 142 143 p = fw_getmdesc(config_enabled(CONFIG_EVA)); 144 free_init_pages_eva = (config_enabled(CONFIG_EVA) ? 145 free_init_pages_eva_malta : NULL); 146 147 while (p->size) { 148 long type; 149 unsigned long base, size; 150 151 type = fw_memtype_classify(p->type); 152 base = p->base; 153 size = p->size; 154 155 add_memory_region(base, size, type); 156 p++; 157 } 158 } 159 160 void __init prom_free_prom_memory(void) 161 { 162 unsigned long addr; 163 int i; 164 165 for (i = 0; i < boot_mem_map.nr_map; i++) { 166 if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA) 167 continue; 168 169 addr = boot_mem_map.map[i].addr; 170 free_init_pages("YAMON memory", 171 addr, addr + boot_mem_map.map[i].size); 172 } 173 } 174 175 unsigned platform_maar_init(unsigned num_pairs) 176 { 177 phys_addr_t mem_end = (physical_memsize & ~0xffffull) - 1; 178 struct maar_config cfg[] = { 179 /* DRAM preceding I/O */ 180 { 0x00000000, 0x0fffffff, MIPS_MAAR_S }, 181 182 /* DRAM following I/O */ 183 { 0x20000000, mem_end, MIPS_MAAR_S }, 184 185 /* DRAM alias in upper half of physical */ 186 { 0x80000000, 0x80000000 + mem_end, MIPS_MAAR_S }, 187 }; 188 unsigned i, num_cfg = ARRAY_SIZE(cfg); 189 190 /* If DRAM fits before I/O, drop the region following it */ 191 if (physical_memsize <= 0x10000000) { 192 num_cfg--; 193 for (i = 1; i < num_cfg; i++) 194 cfg[i] = cfg[i + 1]; 195 } 196 197 return maar_config(cfg, num_cfg, num_pairs); 198 } 199