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/lmb.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 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 int i; 73 unsigned long map_size; 74 #ifndef CONFIG_MMU 75 u32 kernel_align_start, kernel_align_size; 76 77 /* Find main memory where is the kernel */ 78 for (i = 0; i < lmb.memory.cnt; i++) { 79 memory_start = (u32) lmb.memory.region[i].base; 80 memory_end = (u32) lmb.memory.region[i].base 81 + (u32) lmb.memory.region[i].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 lmb_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 #ifndef CONFIG_MMU 137 map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)klimit)), 138 min_low_pfn, max_low_pfn); 139 #else 140 map_size = init_bootmem_node(&contig_page_data, 141 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn); 142 #endif 143 lmb_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size); 144 145 /* free bootmem is whole main memory */ 146 free_bootmem(memory_start, memory_size); 147 148 /* reserve allocate blocks */ 149 for (i = 0; i < lmb.reserved.cnt; i++) { 150 pr_debug("reserved %d - 0x%08x-0x%08x\n", i, 151 (u32) lmb.reserved.region[i].base, 152 (u32) lmb_size_bytes(&lmb.reserved, i)); 153 reserve_bootmem(lmb.reserved.region[i].base, 154 lmb_size_bytes(&lmb.reserved, i) - 1, BOOTMEM_DEFAULT); 155 } 156 #ifdef CONFIG_MMU 157 init_bootmem_done = 1; 158 #endif 159 paging_init(); 160 } 161 162 void free_init_pages(char *what, unsigned long begin, unsigned long end) 163 { 164 unsigned long addr; 165 166 for (addr = begin; addr < end; addr += PAGE_SIZE) { 167 ClearPageReserved(virt_to_page(addr)); 168 init_page_count(virt_to_page(addr)); 169 free_page(addr); 170 totalram_pages++; 171 } 172 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 173 } 174 175 #ifdef CONFIG_BLK_DEV_INITRD 176 void free_initrd_mem(unsigned long start, unsigned long end) 177 { 178 int pages = 0; 179 for (; start < end; start += PAGE_SIZE) { 180 ClearPageReserved(virt_to_page(start)); 181 init_page_count(virt_to_page(start)); 182 free_page(start); 183 totalram_pages++; 184 pages++; 185 } 186 printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", 187 (int)(pages * (PAGE_SIZE / 1024))); 188 } 189 #endif 190 191 void free_initmem(void) 192 { 193 free_init_pages("unused kernel memory", 194 (unsigned long)(&__init_begin), 195 (unsigned long)(&__init_end)); 196 } 197 198 void __init mem_init(void) 199 { 200 high_memory = (void *)__va(memory_end); 201 /* this will put all memory onto the freelists */ 202 totalram_pages += free_all_bootmem(); 203 204 printk(KERN_INFO "Memory: %luk/%luk available\n", 205 nr_free_pages() << (PAGE_SHIFT-10), 206 num_physpages << (PAGE_SHIFT-10)); 207 mem_init_done = 1; 208 } 209 210 #ifndef CONFIG_MMU 211 int page_is_ram(unsigned long pfn) 212 { 213 return __range_ok(pfn, 0); 214 } 215 #else 216 int page_is_ram(unsigned long pfn) 217 { 218 return pfn < max_low_pfn; 219 } 220 221 /* 222 * Check for command-line options that affect what MMU_init will do. 223 */ 224 static void mm_cmdline_setup(void) 225 { 226 unsigned long maxmem = 0; 227 char *p = cmd_line; 228 229 /* Look for mem= option on command line */ 230 p = strstr(cmd_line, "mem="); 231 if (p) { 232 p += 4; 233 maxmem = memparse(p, &p); 234 if (maxmem && memory_size > maxmem) { 235 memory_size = maxmem; 236 memory_end = memory_start + memory_size; 237 lmb.memory.region[0].size = memory_size; 238 } 239 } 240 } 241 242 /* 243 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 244 */ 245 static void __init mmu_init_hw(void) 246 { 247 /* 248 * The Zone Protection Register (ZPR) defines how protection will 249 * be applied to every page which is a member of a given zone. At 250 * present, we utilize only two of the zones. 251 * The zone index bits (of ZSEL) in the PTE are used for software 252 * indicators, except the LSB. For user access, zone 1 is used, 253 * for kernel access, zone 0 is used. We set all but zone 1 254 * to zero, allowing only kernel access as indicated in the PTE. 255 * For zone 1, we set a 01 binary (a value of 10 will not work) 256 * to allow user access as indicated in the PTE. This also allows 257 * kernel access as indicated in the PTE. 258 */ 259 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 260 "mts rzpr, r11;" 261 : : : "r11"); 262 } 263 264 /* 265 * MMU_init sets up the basic memory mappings for the kernel, 266 * including both RAM and possibly some I/O regions, 267 * and sets up the page tables and the MMU hardware ready to go. 268 */ 269 270 /* called from head.S */ 271 asmlinkage void __init mmu_init(void) 272 { 273 unsigned int kstart, ksize; 274 275 if (!lmb.reserved.cnt) { 276 printk(KERN_EMERG "Error memory count\n"); 277 machine_restart(NULL); 278 } 279 280 if ((u32) lmb.memory.region[0].size < 0x1000000) { 281 printk(KERN_EMERG "Memory must be greater than 16MB\n"); 282 machine_restart(NULL); 283 } 284 /* Find main memory where the kernel is */ 285 memory_start = (u32) lmb.memory.region[0].base; 286 memory_end = (u32) lmb.memory.region[0].base + 287 (u32) lmb.memory.region[0].size; 288 memory_size = memory_end - memory_start; 289 290 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 291 292 /* 293 * Map out the kernel text/data/bss from the available physical 294 * memory. 295 */ 296 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 297 /* kernel size */ 298 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 299 lmb_reserve(kstart, ksize); 300 301 #if defined(CONFIG_BLK_DEV_INITRD) 302 /* Remove the init RAM disk from the available memory. */ 303 /* if (initrd_start) { 304 mem_pieces_remove(&phys_avail, __pa(initrd_start), 305 initrd_end - initrd_start, 1); 306 }*/ 307 #endif /* CONFIG_BLK_DEV_INITRD */ 308 309 /* Initialize the MMU hardware */ 310 mmu_init_hw(); 311 312 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 313 mapin_ram(); 314 315 #ifdef HIGHMEM_START_BOOL 316 ioremap_base = HIGHMEM_START; 317 #else 318 ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ 319 #endif /* CONFIG_HIGHMEM */ 320 ioremap_bot = ioremap_base; 321 322 /* Initialize the context management stuff */ 323 mmu_context_init(); 324 } 325 326 /* This is only called until mem_init is done. */ 327 void __init *early_get_page(void) 328 { 329 void *p; 330 if (init_bootmem_done) { 331 p = alloc_bootmem_pages(PAGE_SIZE); 332 } else { 333 /* 334 * Mem start + 32MB -> here is limit 335 * because of mem mapping from head.S 336 */ 337 p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE, 338 memory_start + 0x2000000)); 339 } 340 return p; 341 } 342 343 #endif /* CONFIG_MMU */ 344 345 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask) 346 { 347 if (mem_init_done) 348 return kmalloc(size, mask); 349 else 350 return alloc_bootmem(size); 351 } 352 353 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask) 354 { 355 void *p; 356 357 if (mem_init_done) 358 p = kzalloc(size, mask); 359 else { 360 p = alloc_bootmem(size); 361 if (p) 362 memset(p, 0, size); 363 } 364 return p; 365 } 366