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 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 36 37 static int init_bootmem_done; 38 #endif /* CONFIG_MMU */ 39 40 char *klimit = _end; 41 42 /* 43 * Initialize the bootmem system and give it all the memory we 44 * have available. 45 */ 46 unsigned long memory_start; 47 EXPORT_SYMBOL(memory_start); 48 unsigned long memory_end; /* due to mm/nommu.c */ 49 unsigned long memory_size; 50 EXPORT_SYMBOL(memory_size); 51 52 /* 53 * paging_init() sets up the page tables - in fact we've already done this. 54 */ 55 static void __init paging_init(void) 56 { 57 unsigned long zones_size[MAX_NR_ZONES]; 58 59 /* Clean every zones */ 60 memset(zones_size, 0, sizeof(zones_size)); 61 62 /* 63 * old: we can DMA to/from any address.put all page into ZONE_DMA 64 * We use only ZONE_NORMAL 65 */ 66 zones_size[ZONE_NORMAL] = max_mapnr; 67 68 free_area_init(zones_size); 69 } 70 71 void __init setup_memory(void) 72 { 73 unsigned long map_size; 74 struct memblock_region *reg; 75 76 #ifndef CONFIG_MMU 77 u32 kernel_align_start, kernel_align_size; 78 79 /* Find main memory where is the kernel */ 80 for_each_memblock(memory, reg) { 81 memory_start = (u32)reg->base; 82 memory_end = (u32) reg->base + reg->size; 83 if ((memory_start <= (u32)_text) && 84 ((u32)_text <= memory_end)) { 85 memory_size = memory_end - memory_start; 86 PAGE_OFFSET = memory_start; 87 printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, " 88 "size 0x%08x\n", __func__, (u32) memory_start, 89 (u32) memory_end, (u32) memory_size); 90 break; 91 } 92 } 93 94 if (!memory_start || !memory_end) { 95 panic("%s: Missing memory setting 0x%08x-0x%08x\n", 96 __func__, (u32) memory_start, (u32) memory_end); 97 } 98 99 /* reservation of region where is the kernel */ 100 kernel_align_start = PAGE_DOWN((u32)_text); 101 /* ALIGN can be remove because _end in vmlinux.lds.S is align */ 102 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; 103 memblock_reserve(kernel_align_start, kernel_align_size); 104 printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n", 105 __func__, kernel_align_start, kernel_align_start 106 + kernel_align_size, kernel_align_size); 107 108 #endif 109 /* 110 * Kernel: 111 * start: base phys address of kernel - page align 112 * end: base phys address of kernel - page align 113 * 114 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) 115 * max_low_pfn 116 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) 117 * num_physpages - number of all pages 118 */ 119 120 /* memory start is from the kernel end (aligned) to higher addr */ 121 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ 122 /* RAM is assumed contiguous */ 123 num_physpages = max_mapnr = memory_size >> PAGE_SHIFT; 124 max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT; 125 126 printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr); 127 printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); 128 printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); 129 130 /* 131 * Find an area to use for the bootmem bitmap. 132 * We look for the first area which is at least 133 * 128kB in length (128kB is enough for a bitmap 134 * for 4GB of memory, using 4kB pages), plus 1 page 135 * (in case the address isn't page-aligned). 136 */ 137 map_size = init_bootmem_node(NODE_DATA(0), 138 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn); 139 memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size); 140 141 /* free bootmem is whole main memory */ 142 free_bootmem(memory_start, memory_size); 143 144 /* reserve allocate blocks */ 145 for_each_memblock(reserved, reg) { 146 pr_debug("reserved - 0x%08x-0x%08x\n", 147 (u32) reg->base, (u32) reg->size); 148 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT); 149 } 150 #ifdef CONFIG_MMU 151 init_bootmem_done = 1; 152 #endif 153 paging_init(); 154 } 155 156 void free_init_pages(char *what, unsigned long begin, unsigned long end) 157 { 158 unsigned long addr; 159 160 for (addr = begin; addr < end; addr += PAGE_SIZE) { 161 ClearPageReserved(virt_to_page(addr)); 162 init_page_count(virt_to_page(addr)); 163 free_page(addr); 164 totalram_pages++; 165 } 166 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 167 } 168 169 #ifdef CONFIG_BLK_DEV_INITRD 170 void free_initrd_mem(unsigned long start, unsigned long end) 171 { 172 int pages = 0; 173 for (; start < end; start += PAGE_SIZE) { 174 ClearPageReserved(virt_to_page(start)); 175 init_page_count(virt_to_page(start)); 176 free_page(start); 177 totalram_pages++; 178 pages++; 179 } 180 printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", 181 (int)(pages * (PAGE_SIZE / 1024))); 182 } 183 #endif 184 185 void free_initmem(void) 186 { 187 free_init_pages("unused kernel memory", 188 (unsigned long)(&__init_begin), 189 (unsigned long)(&__init_end)); 190 } 191 192 void __init mem_init(void) 193 { 194 high_memory = (void *)__va(memory_end); 195 /* this will put all memory onto the freelists */ 196 totalram_pages += free_all_bootmem(); 197 198 printk(KERN_INFO "Memory: %luk/%luk available\n", 199 nr_free_pages() << (PAGE_SHIFT-10), 200 num_physpages << (PAGE_SHIFT-10)); 201 mem_init_done = 1; 202 } 203 204 #ifndef CONFIG_MMU 205 int page_is_ram(unsigned long pfn) 206 { 207 return __range_ok(pfn, 0); 208 } 209 #else 210 int page_is_ram(unsigned long pfn) 211 { 212 return pfn < max_low_pfn; 213 } 214 215 /* 216 * Check for command-line options that affect what MMU_init will do. 217 */ 218 static void mm_cmdline_setup(void) 219 { 220 unsigned long maxmem = 0; 221 char *p = cmd_line; 222 223 /* Look for mem= option on command line */ 224 p = strstr(cmd_line, "mem="); 225 if (p) { 226 p += 4; 227 maxmem = memparse(p, &p); 228 if (maxmem && memory_size > maxmem) { 229 memory_size = maxmem; 230 memory_end = memory_start + memory_size; 231 memblock.memory.regions[0].size = memory_size; 232 } 233 } 234 } 235 236 /* 237 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 238 */ 239 static void __init mmu_init_hw(void) 240 { 241 /* 242 * The Zone Protection Register (ZPR) defines how protection will 243 * be applied to every page which is a member of a given zone. At 244 * present, we utilize only two of the zones. 245 * The zone index bits (of ZSEL) in the PTE are used for software 246 * indicators, except the LSB. For user access, zone 1 is used, 247 * for kernel access, zone 0 is used. We set all but zone 1 248 * to zero, allowing only kernel access as indicated in the PTE. 249 * For zone 1, we set a 01 binary (a value of 10 will not work) 250 * to allow user access as indicated in the PTE. This also allows 251 * kernel access as indicated in the PTE. 252 */ 253 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 254 "mts rzpr, r11;" 255 : : : "r11"); 256 } 257 258 /* 259 * MMU_init sets up the basic memory mappings for the kernel, 260 * including both RAM and possibly some I/O regions, 261 * and sets up the page tables and the MMU hardware ready to go. 262 */ 263 264 /* called from head.S */ 265 asmlinkage void __init mmu_init(void) 266 { 267 unsigned int kstart, ksize; 268 269 if (!memblock.reserved.cnt) { 270 printk(KERN_EMERG "Error memory count\n"); 271 machine_restart(NULL); 272 } 273 274 if ((u32) memblock.memory.regions[0].size < 0x1000000) { 275 printk(KERN_EMERG "Memory must be greater than 16MB\n"); 276 machine_restart(NULL); 277 } 278 /* Find main memory where the kernel is */ 279 memory_start = (u32) memblock.memory.regions[0].base; 280 memory_end = (u32) memblock.memory.regions[0].base + 281 (u32) memblock.memory.regions[0].size; 282 memory_size = memory_end - memory_start; 283 284 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 285 286 /* 287 * Map out the kernel text/data/bss from the available physical 288 * memory. 289 */ 290 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 291 /* kernel size */ 292 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 293 memblock_reserve(kstart, ksize); 294 295 #if defined(CONFIG_BLK_DEV_INITRD) 296 /* Remove the init RAM disk from the available memory. */ 297 /* if (initrd_start) { 298 mem_pieces_remove(&phys_avail, __pa(initrd_start), 299 initrd_end - initrd_start, 1); 300 }*/ 301 #endif /* CONFIG_BLK_DEV_INITRD */ 302 303 /* Initialize the MMU hardware */ 304 mmu_init_hw(); 305 306 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 307 mapin_ram(); 308 309 #ifdef HIGHMEM_START_BOOL 310 ioremap_base = HIGHMEM_START; 311 #else 312 ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ 313 #endif /* CONFIG_HIGHMEM */ 314 ioremap_bot = ioremap_base; 315 316 /* Initialize the context management stuff */ 317 mmu_context_init(); 318 } 319 320 /* This is only called until mem_init is done. */ 321 void __init *early_get_page(void) 322 { 323 void *p; 324 if (init_bootmem_done) { 325 p = alloc_bootmem_pages(PAGE_SIZE); 326 } else { 327 /* 328 * Mem start + 32MB -> here is limit 329 * because of mem mapping from head.S 330 */ 331 p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE, 332 memory_start + 0x2000000)); 333 } 334 return p; 335 } 336 337 #endif /* CONFIG_MMU */ 338 339 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask) 340 { 341 if (mem_init_done) 342 return kmalloc(size, mask); 343 else 344 return alloc_bootmem(size); 345 } 346 347 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask) 348 { 349 void *p; 350 351 if (mem_init_done) 352 p = kzalloc(size, mask); 353 else { 354 p = alloc_bootmem(size); 355 if (p) 356 memset(p, 0, size); 357 } 358 return p; 359 } 360