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 int i; 74 unsigned long map_size; 75 #ifndef CONFIG_MMU 76 u32 kernel_align_start, kernel_align_size; 77 78 /* Find main memory where is the kernel */ 79 for (i = 0; i < memblock.memory.cnt; i++) { 80 memory_start = (u32) memblock.memory.region[i].base; 81 memory_end = (u32) memblock.memory.region[i].base 82 + (u32) memblock.memory.region[i].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 (i = 0; i < memblock.reserved.cnt; i++) { 146 pr_debug("reserved %d - 0x%08x-0x%08x\n", i, 147 (u32) memblock.reserved.region[i].base, 148 (u32) memblock_size_bytes(&memblock.reserved, i)); 149 reserve_bootmem(memblock.reserved.region[i].base, 150 memblock_size_bytes(&memblock.reserved, i) - 1, BOOTMEM_DEFAULT); 151 } 152 #ifdef CONFIG_MMU 153 init_bootmem_done = 1; 154 #endif 155 paging_init(); 156 } 157 158 void free_init_pages(char *what, unsigned long begin, unsigned long end) 159 { 160 unsigned long addr; 161 162 for (addr = begin; addr < end; addr += PAGE_SIZE) { 163 ClearPageReserved(virt_to_page(addr)); 164 init_page_count(virt_to_page(addr)); 165 free_page(addr); 166 totalram_pages++; 167 } 168 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 169 } 170 171 #ifdef CONFIG_BLK_DEV_INITRD 172 void free_initrd_mem(unsigned long start, unsigned long end) 173 { 174 int pages = 0; 175 for (; start < end; start += PAGE_SIZE) { 176 ClearPageReserved(virt_to_page(start)); 177 init_page_count(virt_to_page(start)); 178 free_page(start); 179 totalram_pages++; 180 pages++; 181 } 182 printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", 183 (int)(pages * (PAGE_SIZE / 1024))); 184 } 185 #endif 186 187 void free_initmem(void) 188 { 189 free_init_pages("unused kernel memory", 190 (unsigned long)(&__init_begin), 191 (unsigned long)(&__init_end)); 192 } 193 194 void __init mem_init(void) 195 { 196 high_memory = (void *)__va(memory_end); 197 /* this will put all memory onto the freelists */ 198 totalram_pages += free_all_bootmem(); 199 200 printk(KERN_INFO "Memory: %luk/%luk available\n", 201 nr_free_pages() << (PAGE_SHIFT-10), 202 num_physpages << (PAGE_SHIFT-10)); 203 mem_init_done = 1; 204 } 205 206 #ifndef CONFIG_MMU 207 int page_is_ram(unsigned long pfn) 208 { 209 return __range_ok(pfn, 0); 210 } 211 #else 212 int page_is_ram(unsigned long pfn) 213 { 214 return pfn < max_low_pfn; 215 } 216 217 /* 218 * Check for command-line options that affect what MMU_init will do. 219 */ 220 static void mm_cmdline_setup(void) 221 { 222 unsigned long maxmem = 0; 223 char *p = cmd_line; 224 225 /* Look for mem= option on command line */ 226 p = strstr(cmd_line, "mem="); 227 if (p) { 228 p += 4; 229 maxmem = memparse(p, &p); 230 if (maxmem && memory_size > maxmem) { 231 memory_size = maxmem; 232 memory_end = memory_start + memory_size; 233 memblock.memory.region[0].size = memory_size; 234 } 235 } 236 } 237 238 /* 239 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 240 */ 241 static void __init mmu_init_hw(void) 242 { 243 /* 244 * The Zone Protection Register (ZPR) defines how protection will 245 * be applied to every page which is a member of a given zone. At 246 * present, we utilize only two of the zones. 247 * The zone index bits (of ZSEL) in the PTE are used for software 248 * indicators, except the LSB. For user access, zone 1 is used, 249 * for kernel access, zone 0 is used. We set all but zone 1 250 * to zero, allowing only kernel access as indicated in the PTE. 251 * For zone 1, we set a 01 binary (a value of 10 will not work) 252 * to allow user access as indicated in the PTE. This also allows 253 * kernel access as indicated in the PTE. 254 */ 255 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 256 "mts rzpr, r11;" 257 : : : "r11"); 258 } 259 260 /* 261 * MMU_init sets up the basic memory mappings for the kernel, 262 * including both RAM and possibly some I/O regions, 263 * and sets up the page tables and the MMU hardware ready to go. 264 */ 265 266 /* called from head.S */ 267 asmlinkage void __init mmu_init(void) 268 { 269 unsigned int kstart, ksize; 270 271 if (!memblock.reserved.cnt) { 272 printk(KERN_EMERG "Error memory count\n"); 273 machine_restart(NULL); 274 } 275 276 if ((u32) memblock.memory.region[0].size < 0x1000000) { 277 printk(KERN_EMERG "Memory must be greater than 16MB\n"); 278 machine_restart(NULL); 279 } 280 /* Find main memory where the kernel is */ 281 memory_start = (u32) memblock.memory.region[0].base; 282 memory_end = (u32) memblock.memory.region[0].base + 283 (u32) memblock.memory.region[0].size; 284 memory_size = memory_end - memory_start; 285 286 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 287 288 /* 289 * Map out the kernel text/data/bss from the available physical 290 * memory. 291 */ 292 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 293 /* kernel size */ 294 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 295 memblock_reserve(kstart, ksize); 296 297 #if defined(CONFIG_BLK_DEV_INITRD) 298 /* Remove the init RAM disk from the available memory. */ 299 /* if (initrd_start) { 300 mem_pieces_remove(&phys_avail, __pa(initrd_start), 301 initrd_end - initrd_start, 1); 302 }*/ 303 #endif /* CONFIG_BLK_DEV_INITRD */ 304 305 /* Initialize the MMU hardware */ 306 mmu_init_hw(); 307 308 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 309 mapin_ram(); 310 311 #ifdef HIGHMEM_START_BOOL 312 ioremap_base = HIGHMEM_START; 313 #else 314 ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ 315 #endif /* CONFIG_HIGHMEM */ 316 ioremap_bot = ioremap_base; 317 318 /* Initialize the context management stuff */ 319 mmu_context_init(); 320 } 321 322 /* This is only called until mem_init is done. */ 323 void __init *early_get_page(void) 324 { 325 void *p; 326 if (init_bootmem_done) { 327 p = alloc_bootmem_pages(PAGE_SIZE); 328 } else { 329 /* 330 * Mem start + 32MB -> here is limit 331 * because of mem mapping from head.S 332 */ 333 p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE, 334 memory_start + 0x2000000)); 335 } 336 return p; 337 } 338 339 #endif /* CONFIG_MMU */ 340 341 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask) 342 { 343 if (mem_init_done) 344 return kmalloc(size, mask); 345 else 346 return alloc_bootmem(size); 347 } 348 349 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask) 350 { 351 void *p; 352 353 if (mem_init_done) 354 p = kzalloc(size, mask); 355 else { 356 p = alloc_bootmem(size); 357 if (p) 358 memset(p, 0, size); 359 } 360 return p; 361 } 362