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 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 < lmb.memory.cnt; i++) { 80 memory_start = (u32) lmb.memory.region[i].base; 81 memory_end = (u32) lmb.memory.region[i].base 82 + (u32) lmb.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 lmb_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 #ifndef CONFIG_MMU 138 map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)klimit)), 139 min_low_pfn, max_low_pfn); 140 #else 141 map_size = init_bootmem_node(&contig_page_data, 142 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn); 143 #endif 144 lmb_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size); 145 146 /* free bootmem is whole main memory */ 147 free_bootmem(memory_start, memory_size); 148 149 /* reserve allocate blocks */ 150 for (i = 0; i < lmb.reserved.cnt; i++) { 151 pr_debug("reserved %d - 0x%08x-0x%08x\n", i, 152 (u32) lmb.reserved.region[i].base, 153 (u32) lmb_size_bytes(&lmb.reserved, i)); 154 reserve_bootmem(lmb.reserved.region[i].base, 155 lmb_size_bytes(&lmb.reserved, i) - 1, BOOTMEM_DEFAULT); 156 } 157 #ifdef CONFIG_MMU 158 init_bootmem_done = 1; 159 #endif 160 paging_init(); 161 } 162 163 void free_init_pages(char *what, unsigned long begin, unsigned long end) 164 { 165 unsigned long addr; 166 167 for (addr = begin; addr < end; addr += PAGE_SIZE) { 168 ClearPageReserved(virt_to_page(addr)); 169 init_page_count(virt_to_page(addr)); 170 free_page(addr); 171 totalram_pages++; 172 } 173 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 174 } 175 176 #ifdef CONFIG_BLK_DEV_INITRD 177 void free_initrd_mem(unsigned long start, unsigned long end) 178 { 179 int pages = 0; 180 for (; start < end; start += PAGE_SIZE) { 181 ClearPageReserved(virt_to_page(start)); 182 init_page_count(virt_to_page(start)); 183 free_page(start); 184 totalram_pages++; 185 pages++; 186 } 187 printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", 188 (int)(pages * (PAGE_SIZE / 1024))); 189 } 190 #endif 191 192 void free_initmem(void) 193 { 194 free_init_pages("unused kernel memory", 195 (unsigned long)(&__init_begin), 196 (unsigned long)(&__init_end)); 197 } 198 199 void __init mem_init(void) 200 { 201 high_memory = (void *)__va(memory_end); 202 /* this will put all memory onto the freelists */ 203 totalram_pages += free_all_bootmem(); 204 205 printk(KERN_INFO "Memory: %luk/%luk available\n", 206 nr_free_pages() << (PAGE_SHIFT-10), 207 num_physpages << (PAGE_SHIFT-10)); 208 mem_init_done = 1; 209 } 210 211 #ifndef CONFIG_MMU 212 int page_is_ram(unsigned long pfn) 213 { 214 return __range_ok(pfn, 0); 215 } 216 #else 217 int page_is_ram(unsigned long pfn) 218 { 219 return pfn < max_low_pfn; 220 } 221 222 /* 223 * Check for command-line options that affect what MMU_init will do. 224 */ 225 static void mm_cmdline_setup(void) 226 { 227 unsigned long maxmem = 0; 228 char *p = cmd_line; 229 230 /* Look for mem= option on command line */ 231 p = strstr(cmd_line, "mem="); 232 if (p) { 233 p += 4; 234 maxmem = memparse(p, &p); 235 if (maxmem && memory_size > maxmem) { 236 memory_size = maxmem; 237 memory_end = memory_start + memory_size; 238 lmb.memory.region[0].size = memory_size; 239 } 240 } 241 } 242 243 /* 244 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 245 */ 246 static void __init mmu_init_hw(void) 247 { 248 /* 249 * The Zone Protection Register (ZPR) defines how protection will 250 * be applied to every page which is a member of a given zone. At 251 * present, we utilize only two of the zones. 252 * The zone index bits (of ZSEL) in the PTE are used for software 253 * indicators, except the LSB. For user access, zone 1 is used, 254 * for kernel access, zone 0 is used. We set all but zone 1 255 * to zero, allowing only kernel access as indicated in the PTE. 256 * For zone 1, we set a 01 binary (a value of 10 will not work) 257 * to allow user access as indicated in the PTE. This also allows 258 * kernel access as indicated in the PTE. 259 */ 260 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 261 "mts rzpr, r11;" 262 : : : "r11"); 263 } 264 265 /* 266 * MMU_init sets up the basic memory mappings for the kernel, 267 * including both RAM and possibly some I/O regions, 268 * and sets up the page tables and the MMU hardware ready to go. 269 */ 270 271 /* called from head.S */ 272 asmlinkage void __init mmu_init(void) 273 { 274 unsigned int kstart, ksize; 275 276 if (!lmb.reserved.cnt) { 277 printk(KERN_EMERG "Error memory count\n"); 278 machine_restart(NULL); 279 } 280 281 if ((u32) lmb.memory.region[0].size < 0x1000000) { 282 printk(KERN_EMERG "Memory must be greater than 16MB\n"); 283 machine_restart(NULL); 284 } 285 /* Find main memory where the kernel is */ 286 memory_start = (u32) lmb.memory.region[0].base; 287 memory_end = (u32) lmb.memory.region[0].base + 288 (u32) lmb.memory.region[0].size; 289 memory_size = memory_end - memory_start; 290 291 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 292 293 /* 294 * Map out the kernel text/data/bss from the available physical 295 * memory. 296 */ 297 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 298 /* kernel size */ 299 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 300 lmb_reserve(kstart, ksize); 301 302 #if defined(CONFIG_BLK_DEV_INITRD) 303 /* Remove the init RAM disk from the available memory. */ 304 /* if (initrd_start) { 305 mem_pieces_remove(&phys_avail, __pa(initrd_start), 306 initrd_end - initrd_start, 1); 307 }*/ 308 #endif /* CONFIG_BLK_DEV_INITRD */ 309 310 /* Initialize the MMU hardware */ 311 mmu_init_hw(); 312 313 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 314 mapin_ram(); 315 316 #ifdef HIGHMEM_START_BOOL 317 ioremap_base = HIGHMEM_START; 318 #else 319 ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ 320 #endif /* CONFIG_HIGHMEM */ 321 ioremap_bot = ioremap_base; 322 323 /* Initialize the context management stuff */ 324 mmu_context_init(); 325 } 326 327 /* This is only called until mem_init is done. */ 328 void __init *early_get_page(void) 329 { 330 void *p; 331 if (init_bootmem_done) { 332 p = alloc_bootmem_pages(PAGE_SIZE); 333 } else { 334 /* 335 * Mem start + 32MB -> here is limit 336 * because of mem mapping from head.S 337 */ 338 p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE, 339 memory_start + 0x2000000)); 340 } 341 return p; 342 } 343 344 #endif /* CONFIG_MMU */ 345 346 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask) 347 { 348 if (mem_init_done) 349 return kmalloc(size, mask); 350 else 351 return alloc_bootmem(size); 352 } 353 354 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask) 355 { 356 void *p; 357 358 if (mem_init_done) 359 p = kzalloc(size, mask); 360 else { 361 p = alloc_bootmem(size); 362 if (p) 363 memset(p, 0, size); 364 } 365 return p; 366 } 367