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/cdmm.h> 20 #include <asm/maar.h> 21 #include <asm/sections.h> 22 #include <asm/fw/fw.h> 23 24 static fw_memblock_t mdesc[FW_MAX_MEMBLOCKS]; 25 26 /* determined physical memory size, not overridden by command line args */ 27 unsigned long physical_memsize = 0L; 28 29 fw_memblock_t * __init fw_getmdesc(int eva) 30 { 31 char *memsize_str, *ememsize_str = NULL, *ptr; 32 unsigned long memsize = 0, ememsize = 0; 33 static char cmdline[COMMAND_LINE_SIZE] __initdata; 34 int tmp; 35 36 /* otherwise look in the environment */ 37 38 memsize_str = fw_getenv("memsize"); 39 if (memsize_str) { 40 tmp = kstrtoul(memsize_str, 0, &memsize); 41 if (tmp) 42 pr_warn("Failed to read the 'memsize' env variable.\n"); 43 } 44 if (eva) { 45 /* Look for ememsize for EVA */ 46 ememsize_str = fw_getenv("ememsize"); 47 if (ememsize_str) { 48 tmp = kstrtoul(ememsize_str, 0, &ememsize); 49 if (tmp) 50 pr_warn("Failed to read the 'ememsize' env variable.\n"); 51 } 52 } 53 if (!memsize && !ememsize) { 54 pr_warn("memsize not set in YAMON, set to default (32Mb)\n"); 55 physical_memsize = 0x02000000; 56 } else { 57 if (memsize > (256 << 20)) { /* memsize should be capped to 256M */ 58 pr_warn("Unsupported memsize value (0x%lx) detected! " 59 "Using 0x10000000 (256M) instead\n", 60 memsize); 61 memsize = 256 << 20; 62 } 63 /* If ememsize is set, then set physical_memsize to that */ 64 physical_memsize = ememsize ? : memsize; 65 } 66 67 #ifdef CONFIG_CPU_BIG_ENDIAN 68 /* SOC-it swaps, or perhaps doesn't swap, when DMA'ing the last 69 word of physical memory */ 70 physical_memsize -= PAGE_SIZE; 71 #endif 72 73 /* Check the command line for a memsize directive that overrides 74 the physical/default amount */ 75 strcpy(cmdline, arcs_cmdline); 76 ptr = strstr(cmdline, "memsize="); 77 if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' ')) 78 ptr = strstr(ptr, " memsize="); 79 /* And now look for ememsize */ 80 if (eva) { 81 ptr = strstr(cmdline, "ememsize="); 82 if (ptr && (ptr != cmdline) && (*(ptr - 1) != ' ')) 83 ptr = strstr(ptr, " ememsize="); 84 } 85 86 if (ptr) 87 memsize = memparse(ptr + 8 + (eva ? 1 : 0), &ptr); 88 else 89 memsize = physical_memsize; 90 91 /* Last 64K for HIGHMEM arithmetics */ 92 if (memsize > 0x7fff0000) 93 memsize = 0x7fff0000; 94 95 memset(mdesc, 0, sizeof(mdesc)); 96 97 mdesc[0].type = fw_dontuse; 98 mdesc[0].base = PHYS_OFFSET; 99 mdesc[0].size = 0x00001000; 100 101 mdesc[1].type = fw_code; 102 mdesc[1].base = mdesc[0].base + 0x00001000UL; 103 mdesc[1].size = 0x000ef000; 104 105 /* 106 * The area 0x000f0000-0x000fffff is allocated for BIOS memory by the 107 * south bridge and PCI access always forwarded to the ISA Bus and 108 * BIOSCS# is always generated. 109 * This mean that this area can't be used as DMA memory for PCI 110 * devices. 111 */ 112 mdesc[2].type = fw_dontuse; 113 mdesc[2].base = mdesc[0].base + 0x000f0000UL; 114 mdesc[2].size = 0x00010000; 115 116 mdesc[3].type = fw_dontuse; 117 mdesc[3].base = mdesc[0].base + 0x00100000UL; 118 mdesc[3].size = CPHYSADDR(PFN_ALIGN((unsigned long)&_end)) - 119 0x00100000UL; 120 121 mdesc[4].type = fw_free; 122 mdesc[4].base = mdesc[0].base + CPHYSADDR(PFN_ALIGN(&_end)); 123 mdesc[4].size = memsize - CPHYSADDR(mdesc[4].base); 124 125 return &mdesc[0]; 126 } 127 128 static void free_init_pages_eva_malta(void *begin, void *end) 129 { 130 free_init_pages("unused kernel", __pa_symbol((unsigned long *)begin), 131 __pa_symbol((unsigned long *)end)); 132 } 133 134 static int __init fw_memtype_classify(unsigned int type) 135 { 136 switch (type) { 137 case fw_free: 138 return BOOT_MEM_RAM; 139 case fw_code: 140 return BOOT_MEM_ROM_DATA; 141 default: 142 return BOOT_MEM_RESERVED; 143 } 144 } 145 146 void __init fw_meminit(void) 147 { 148 fw_memblock_t *p; 149 150 p = fw_getmdesc(config_enabled(CONFIG_EVA)); 151 free_init_pages_eva = (config_enabled(CONFIG_EVA) ? 152 free_init_pages_eva_malta : NULL); 153 154 while (p->size) { 155 long type; 156 unsigned long base, size; 157 158 type = fw_memtype_classify(p->type); 159 base = p->base; 160 size = p->size; 161 162 add_memory_region(base, size, type); 163 p++; 164 } 165 } 166 167 void __init prom_free_prom_memory(void) 168 { 169 unsigned long addr; 170 int i; 171 172 for (i = 0; i < boot_mem_map.nr_map; i++) { 173 if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA) 174 continue; 175 176 addr = boot_mem_map.map[i].addr; 177 free_init_pages("YAMON memory", 178 addr, addr + boot_mem_map.map[i].size); 179 } 180 } 181 182 phys_addr_t mips_cdmm_phys_base(void) 183 { 184 /* This address is "typically unused" */ 185 return 0x1fc10000; 186 } 187