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 #include <linux/export.h> 21 22 #include <asm/page.h> 23 #include <asm/mmu_context.h> 24 #include <asm/pgalloc.h> 25 #include <asm/sections.h> 26 #include <asm/tlb.h> 27 28 /* Use for MMU and noMMU because of PCI generic code */ 29 int mem_init_done; 30 31 #ifndef CONFIG_MMU 32 unsigned int __page_offset; 33 EXPORT_SYMBOL(__page_offset); 34 35 #else 36 static int init_bootmem_done; 37 #endif /* CONFIG_MMU */ 38 39 char *klimit = _end; 40 41 /* 42 * Initialize the bootmem system and give it all the memory we 43 * have available. 44 */ 45 unsigned long memory_start; 46 EXPORT_SYMBOL(memory_start); 47 unsigned long memory_end; /* due to mm/nommu.c */ 48 unsigned long memory_size; 49 EXPORT_SYMBOL(memory_size); 50 51 /* 52 * paging_init() sets up the page tables - in fact we've already done this. 53 */ 54 static void __init paging_init(void) 55 { 56 unsigned long zones_size[MAX_NR_ZONES]; 57 58 /* Clean every zones */ 59 memset(zones_size, 0, sizeof(zones_size)); 60 61 /* 62 * old: we can DMA to/from any address.put all page into ZONE_DMA 63 * We use only ZONE_NORMAL 64 */ 65 zones_size[ZONE_NORMAL] = max_mapnr; 66 67 free_area_init(zones_size); 68 } 69 70 void __init setup_memory(void) 71 { 72 unsigned long map_size; 73 struct memblock_region *reg; 74 75 #ifndef CONFIG_MMU 76 u32 kernel_align_start, kernel_align_size; 77 78 /* Find main memory where is the kernel */ 79 for_each_memblock(memory, reg) { 80 memory_start = (u32)reg->base; 81 memory_end = (u32) reg->base + reg->size; 82 if ((memory_start <= (u32)_text) && 83 ((u32)_text <= memory_end)) { 84 memory_size = memory_end - memory_start; 85 PAGE_OFFSET = memory_start; 86 printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, " 87 "size 0x%08x\n", __func__, (u32) memory_start, 88 (u32) memory_end, (u32) memory_size); 89 break; 90 } 91 } 92 93 if (!memory_start || !memory_end) { 94 panic("%s: Missing memory setting 0x%08x-0x%08x\n", 95 __func__, (u32) memory_start, (u32) memory_end); 96 } 97 98 /* reservation of region where is the kernel */ 99 kernel_align_start = PAGE_DOWN((u32)_text); 100 /* ALIGN can be remove because _end in vmlinux.lds.S is align */ 101 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; 102 memblock_reserve(kernel_align_start, kernel_align_size); 103 printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n", 104 __func__, kernel_align_start, kernel_align_start 105 + kernel_align_size, kernel_align_size); 106 107 #endif 108 /* 109 * Kernel: 110 * start: base phys address of kernel - page align 111 * end: base phys address of kernel - page align 112 * 113 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) 114 * max_low_pfn 115 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) 116 * num_physpages - number of all pages 117 */ 118 119 /* memory start is from the kernel end (aligned) to higher addr */ 120 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ 121 /* RAM is assumed contiguous */ 122 num_physpages = max_mapnr = memory_size >> PAGE_SHIFT; 123 max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT; 124 125 printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr); 126 printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); 127 printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); 128 129 /* 130 * Find an area to use for the bootmem bitmap. 131 * We look for the first area which is at least 132 * 128kB in length (128kB is enough for a bitmap 133 * for 4GB of memory, using 4kB pages), plus 1 page 134 * (in case the address isn't page-aligned). 135 */ 136 map_size = init_bootmem_node(NODE_DATA(0), 137 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn); 138 memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size); 139 140 /* free bootmem is whole main memory */ 141 free_bootmem(memory_start, memory_size); 142 143 /* reserve allocate blocks */ 144 for_each_memblock(reserved, reg) { 145 pr_debug("reserved - 0x%08x-0x%08x\n", 146 (u32) reg->base, (u32) reg->size); 147 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT); 148 } 149 #ifdef CONFIG_MMU 150 init_bootmem_done = 1; 151 #endif 152 paging_init(); 153 } 154 155 void free_init_pages(char *what, unsigned long begin, unsigned long end) 156 { 157 unsigned long addr; 158 159 for (addr = begin; addr < end; addr += PAGE_SIZE) { 160 ClearPageReserved(virt_to_page(addr)); 161 init_page_count(virt_to_page(addr)); 162 free_page(addr); 163 totalram_pages++; 164 } 165 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 166 } 167 168 #ifdef CONFIG_BLK_DEV_INITRD 169 void free_initrd_mem(unsigned long start, unsigned long end) 170 { 171 int pages = 0; 172 for (; start < end; start += PAGE_SIZE) { 173 ClearPageReserved(virt_to_page(start)); 174 init_page_count(virt_to_page(start)); 175 free_page(start); 176 totalram_pages++; 177 pages++; 178 } 179 printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", 180 (int)(pages * (PAGE_SIZE / 1024))); 181 } 182 #endif 183 184 void free_initmem(void) 185 { 186 free_init_pages("unused kernel memory", 187 (unsigned long)(&__init_begin), 188 (unsigned long)(&__init_end)); 189 } 190 191 void __init mem_init(void) 192 { 193 high_memory = (void *)__va(memory_end); 194 /* this will put all memory onto the freelists */ 195 totalram_pages += free_all_bootmem(); 196 197 printk(KERN_INFO "Memory: %luk/%luk available\n", 198 nr_free_pages() << (PAGE_SHIFT-10), 199 num_physpages << (PAGE_SHIFT-10)); 200 mem_init_done = 1; 201 } 202 203 #ifndef CONFIG_MMU 204 int page_is_ram(unsigned long pfn) 205 { 206 return __range_ok(pfn, 0); 207 } 208 #else 209 int page_is_ram(unsigned long pfn) 210 { 211 return pfn < max_low_pfn; 212 } 213 214 /* 215 * Check for command-line options that affect what MMU_init will do. 216 */ 217 static void mm_cmdline_setup(void) 218 { 219 unsigned long maxmem = 0; 220 char *p = cmd_line; 221 222 /* Look for mem= option on command line */ 223 p = strstr(cmd_line, "mem="); 224 if (p) { 225 p += 4; 226 maxmem = memparse(p, &p); 227 if (maxmem && memory_size > maxmem) { 228 memory_size = maxmem; 229 memory_end = memory_start + memory_size; 230 memblock.memory.regions[0].size = memory_size; 231 } 232 } 233 } 234 235 /* 236 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 237 */ 238 static void __init mmu_init_hw(void) 239 { 240 /* 241 * The Zone Protection Register (ZPR) defines how protection will 242 * be applied to every page which is a member of a given zone. At 243 * present, we utilize only two of the zones. 244 * The zone index bits (of ZSEL) in the PTE are used for software 245 * indicators, except the LSB. For user access, zone 1 is used, 246 * for kernel access, zone 0 is used. We set all but zone 1 247 * to zero, allowing only kernel access as indicated in the PTE. 248 * For zone 1, we set a 01 binary (a value of 10 will not work) 249 * to allow user access as indicated in the PTE. This also allows 250 * kernel access as indicated in the PTE. 251 */ 252 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 253 "mts rzpr, r11;" 254 : : : "r11"); 255 } 256 257 /* 258 * MMU_init sets up the basic memory mappings for the kernel, 259 * including both RAM and possibly some I/O regions, 260 * and sets up the page tables and the MMU hardware ready to go. 261 */ 262 263 /* called from head.S */ 264 asmlinkage void __init mmu_init(void) 265 { 266 unsigned int kstart, ksize; 267 268 if (!memblock.reserved.cnt) { 269 printk(KERN_EMERG "Error memory count\n"); 270 machine_restart(NULL); 271 } 272 273 if ((u32) memblock.memory.regions[0].size < 0x1000000) { 274 printk(KERN_EMERG "Memory must be greater than 16MB\n"); 275 machine_restart(NULL); 276 } 277 /* Find main memory where the kernel is */ 278 memory_start = (u32) memblock.memory.regions[0].base; 279 memory_end = (u32) memblock.memory.regions[0].base + 280 (u32) memblock.memory.regions[0].size; 281 memory_size = memory_end - memory_start; 282 283 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 284 285 /* 286 * Map out the kernel text/data/bss from the available physical 287 * memory. 288 */ 289 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 290 /* kernel size */ 291 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 292 memblock_reserve(kstart, ksize); 293 294 #if defined(CONFIG_BLK_DEV_INITRD) 295 /* Remove the init RAM disk from the available memory. */ 296 /* if (initrd_start) { 297 mem_pieces_remove(&phys_avail, __pa(initrd_start), 298 initrd_end - initrd_start, 1); 299 }*/ 300 #endif /* CONFIG_BLK_DEV_INITRD */ 301 302 /* Initialize the MMU hardware */ 303 mmu_init_hw(); 304 305 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 306 mapin_ram(); 307 308 #ifdef CONFIG_HIGHMEM_START_BOOL 309 ioremap_base = CONFIG_HIGHMEM_START; 310 #else 311 ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ 312 #endif /* CONFIG_HIGHMEM_START_BOOL */ 313 ioremap_bot = ioremap_base; 314 315 /* Initialize the context management stuff */ 316 mmu_context_init(); 317 } 318 319 /* This is only called until mem_init is done. */ 320 void __init *early_get_page(void) 321 { 322 void *p; 323 if (init_bootmem_done) { 324 p = alloc_bootmem_pages(PAGE_SIZE); 325 } else { 326 /* 327 * Mem start + 32MB -> here is limit 328 * because of mem mapping from head.S 329 */ 330 p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE, 331 memory_start + 0x2000000)); 332 } 333 return p; 334 } 335 336 #endif /* CONFIG_MMU */ 337 338 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask) 339 { 340 if (mem_init_done) 341 return kmalloc(size, mask); 342 else 343 return alloc_bootmem(size); 344 } 345 346 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask) 347 { 348 void *p; 349 350 if (mem_init_done) 351 p = kzalloc(size, mask); 352 else { 353 p = alloc_bootmem(size); 354 if (p) 355 memset(p, 0, size); 356 } 357 return p; 358 } 359