1 /* 2 * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu> 3 * Copyright (C) 2006 Atmark Techno, Inc. 4 * 5 * This file is subject to the terms and conditions of the GNU General Public 6 * License. See the file "COPYING" in the main directory of this archive 7 * for more details. 8 */ 9 10 #include <linux/bootmem.h> 11 #include <linux/init.h> 12 #include <linux/kernel.h> 13 #include <linux/memblock.h> 14 #include <linux/mm.h> /* mem_init */ 15 #include <linux/initrd.h> 16 #include <linux/pagemap.h> 17 #include <linux/pfn.h> 18 #include <linux/slab.h> 19 #include <linux/swap.h> 20 21 #include <asm/page.h> 22 #include <asm/mmu_context.h> 23 #include <asm/pgalloc.h> 24 #include <asm/sections.h> 25 #include <asm/tlb.h> 26 27 /* Use for MMU and noMMU because of PCI generic code */ 28 int mem_init_done; 29 30 #ifndef CONFIG_MMU 31 unsigned int __page_offset; 32 EXPORT_SYMBOL(__page_offset); 33 34 #else 35 static int init_bootmem_done; 36 #endif /* CONFIG_MMU */ 37 38 char *klimit = _end; 39 40 /* 41 * Initialize the bootmem system and give it all the memory we 42 * have available. 43 */ 44 unsigned long memory_start; 45 EXPORT_SYMBOL(memory_start); 46 unsigned long memory_end; /* due to mm/nommu.c */ 47 unsigned long memory_size; 48 EXPORT_SYMBOL(memory_size); 49 50 /* 51 * paging_init() sets up the page tables - in fact we've already done this. 52 */ 53 static void __init paging_init(void) 54 { 55 unsigned long zones_size[MAX_NR_ZONES]; 56 57 /* Clean every zones */ 58 memset(zones_size, 0, sizeof(zones_size)); 59 60 /* 61 * old: we can DMA to/from any address.put all page into ZONE_DMA 62 * We use only ZONE_NORMAL 63 */ 64 zones_size[ZONE_NORMAL] = max_mapnr; 65 66 free_area_init(zones_size); 67 } 68 69 void __init setup_memory(void) 70 { 71 unsigned long map_size; 72 struct memblock_region *reg; 73 74 #ifndef CONFIG_MMU 75 u32 kernel_align_start, kernel_align_size; 76 77 /* Find main memory where is the kernel */ 78 for_each_memblock(memory, reg) { 79 memory_start = (u32)reg->base; 80 memory_end = (u32) reg->base + reg->size; 81 if ((memory_start <= (u32)_text) && 82 ((u32)_text <= memory_end)) { 83 memory_size = memory_end - memory_start; 84 PAGE_OFFSET = memory_start; 85 printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, " 86 "size 0x%08x\n", __func__, (u32) memory_start, 87 (u32) memory_end, (u32) memory_size); 88 break; 89 } 90 } 91 92 if (!memory_start || !memory_end) { 93 panic("%s: Missing memory setting 0x%08x-0x%08x\n", 94 __func__, (u32) memory_start, (u32) memory_end); 95 } 96 97 /* reservation of region where is the kernel */ 98 kernel_align_start = PAGE_DOWN((u32)_text); 99 /* ALIGN can be remove because _end in vmlinux.lds.S is align */ 100 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; 101 memblock_reserve(kernel_align_start, kernel_align_size); 102 printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n", 103 __func__, kernel_align_start, kernel_align_start 104 + kernel_align_size, kernel_align_size); 105 106 #endif 107 /* 108 * Kernel: 109 * start: base phys address of kernel - page align 110 * end: base phys address of kernel - page align 111 * 112 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) 113 * max_low_pfn 114 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) 115 * num_physpages - number of all pages 116 */ 117 118 /* memory start is from the kernel end (aligned) to higher addr */ 119 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ 120 /* RAM is assumed contiguous */ 121 num_physpages = max_mapnr = memory_size >> PAGE_SHIFT; 122 max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT; 123 124 printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr); 125 printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); 126 printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); 127 128 /* 129 * Find an area to use for the bootmem bitmap. 130 * We look for the first area which is at least 131 * 128kB in length (128kB is enough for a bitmap 132 * for 4GB of memory, using 4kB pages), plus 1 page 133 * (in case the address isn't page-aligned). 134 */ 135 map_size = init_bootmem_node(NODE_DATA(0), 136 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn); 137 memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size); 138 139 /* free bootmem is whole main memory */ 140 free_bootmem(memory_start, memory_size); 141 142 /* reserve allocate blocks */ 143 for_each_memblock(reserved, reg) { 144 pr_debug("reserved - 0x%08x-0x%08x\n", 145 (u32) reg->base, (u32) reg->size); 146 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT); 147 } 148 #ifdef CONFIG_MMU 149 init_bootmem_done = 1; 150 #endif 151 paging_init(); 152 } 153 154 void free_init_pages(char *what, unsigned long begin, unsigned long end) 155 { 156 unsigned long addr; 157 158 for (addr = begin; addr < end; addr += PAGE_SIZE) { 159 ClearPageReserved(virt_to_page(addr)); 160 init_page_count(virt_to_page(addr)); 161 free_page(addr); 162 totalram_pages++; 163 } 164 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 165 } 166 167 #ifdef CONFIG_BLK_DEV_INITRD 168 void free_initrd_mem(unsigned long start, unsigned long end) 169 { 170 int pages = 0; 171 for (; start < end; start += PAGE_SIZE) { 172 ClearPageReserved(virt_to_page(start)); 173 init_page_count(virt_to_page(start)); 174 free_page(start); 175 totalram_pages++; 176 pages++; 177 } 178 printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", 179 (int)(pages * (PAGE_SIZE / 1024))); 180 } 181 #endif 182 183 void free_initmem(void) 184 { 185 free_init_pages("unused kernel memory", 186 (unsigned long)(&__init_begin), 187 (unsigned long)(&__init_end)); 188 } 189 190 void __init mem_init(void) 191 { 192 high_memory = (void *)__va(memory_end); 193 /* this will put all memory onto the freelists */ 194 totalram_pages += free_all_bootmem(); 195 196 printk(KERN_INFO "Memory: %luk/%luk available\n", 197 nr_free_pages() << (PAGE_SHIFT-10), 198 num_physpages << (PAGE_SHIFT-10)); 199 mem_init_done = 1; 200 } 201 202 #ifndef CONFIG_MMU 203 int page_is_ram(unsigned long pfn) 204 { 205 return __range_ok(pfn, 0); 206 } 207 #else 208 int page_is_ram(unsigned long pfn) 209 { 210 return pfn < max_low_pfn; 211 } 212 213 /* 214 * Check for command-line options that affect what MMU_init will do. 215 */ 216 static void mm_cmdline_setup(void) 217 { 218 unsigned long maxmem = 0; 219 char *p = cmd_line; 220 221 /* Look for mem= option on command line */ 222 p = strstr(cmd_line, "mem="); 223 if (p) { 224 p += 4; 225 maxmem = memparse(p, &p); 226 if (maxmem && memory_size > maxmem) { 227 memory_size = maxmem; 228 memory_end = memory_start + memory_size; 229 memblock.memory.regions[0].size = memory_size; 230 } 231 } 232 } 233 234 /* 235 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 236 */ 237 static void __init mmu_init_hw(void) 238 { 239 /* 240 * The Zone Protection Register (ZPR) defines how protection will 241 * be applied to every page which is a member of a given zone. At 242 * present, we utilize only two of the zones. 243 * The zone index bits (of ZSEL) in the PTE are used for software 244 * indicators, except the LSB. For user access, zone 1 is used, 245 * for kernel access, zone 0 is used. We set all but zone 1 246 * to zero, allowing only kernel access as indicated in the PTE. 247 * For zone 1, we set a 01 binary (a value of 10 will not work) 248 * to allow user access as indicated in the PTE. This also allows 249 * kernel access as indicated in the PTE. 250 */ 251 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 252 "mts rzpr, r11;" 253 : : : "r11"); 254 } 255 256 /* 257 * MMU_init sets up the basic memory mappings for the kernel, 258 * including both RAM and possibly some I/O regions, 259 * and sets up the page tables and the MMU hardware ready to go. 260 */ 261 262 /* called from head.S */ 263 asmlinkage void __init mmu_init(void) 264 { 265 unsigned int kstart, ksize; 266 267 if (!memblock.reserved.cnt) { 268 printk(KERN_EMERG "Error memory count\n"); 269 machine_restart(NULL); 270 } 271 272 if ((u32) memblock.memory.regions[0].size < 0x1000000) { 273 printk(KERN_EMERG "Memory must be greater than 16MB\n"); 274 machine_restart(NULL); 275 } 276 /* Find main memory where the kernel is */ 277 memory_start = (u32) memblock.memory.regions[0].base; 278 memory_end = (u32) memblock.memory.regions[0].base + 279 (u32) memblock.memory.regions[0].size; 280 memory_size = memory_end - memory_start; 281 282 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 283 284 /* 285 * Map out the kernel text/data/bss from the available physical 286 * memory. 287 */ 288 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 289 /* kernel size */ 290 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 291 memblock_reserve(kstart, ksize); 292 293 #if defined(CONFIG_BLK_DEV_INITRD) 294 /* Remove the init RAM disk from the available memory. */ 295 /* if (initrd_start) { 296 mem_pieces_remove(&phys_avail, __pa(initrd_start), 297 initrd_end - initrd_start, 1); 298 }*/ 299 #endif /* CONFIG_BLK_DEV_INITRD */ 300 301 /* Initialize the MMU hardware */ 302 mmu_init_hw(); 303 304 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 305 mapin_ram(); 306 307 #ifdef CONFIG_HIGHMEM_START_BOOL 308 ioremap_base = CONFIG_HIGHMEM_START; 309 #else 310 ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ 311 #endif /* CONFIG_HIGHMEM_START_BOOL */ 312 ioremap_bot = ioremap_base; 313 314 /* Initialize the context management stuff */ 315 mmu_context_init(); 316 } 317 318 /* This is only called until mem_init is done. */ 319 void __init *early_get_page(void) 320 { 321 void *p; 322 if (init_bootmem_done) { 323 p = alloc_bootmem_pages(PAGE_SIZE); 324 } else { 325 /* 326 * Mem start + 32MB -> here is limit 327 * because of mem mapping from head.S 328 */ 329 p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE, 330 memory_start + 0x2000000)); 331 } 332 return p; 333 } 334 335 #endif /* CONFIG_MMU */ 336 337 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask) 338 { 339 if (mem_init_done) 340 return kmalloc(size, mask); 341 else 342 return alloc_bootmem(size); 343 } 344 345 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask) 346 { 347 void *p; 348 349 if (mem_init_done) 350 p = kzalloc(size, mask); 351 else { 352 p = alloc_bootmem(size); 353 if (p) 354 memset(p, 0, size); 355 } 356 return p; 357 } 358