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/swap.h> 19 20 #include <asm/page.h> 21 #include <asm/mmu_context.h> 22 #include <asm/pgalloc.h> 23 #include <asm/sections.h> 24 #include <asm/tlb.h> 25 26 #ifndef CONFIG_MMU 27 unsigned int __page_offset; 28 EXPORT_SYMBOL(__page_offset); 29 30 #else 31 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 32 33 int mem_init_done; 34 static int init_bootmem_done; 35 #endif /* CONFIG_MMU */ 36 37 char *klimit = _end; 38 39 /* 40 * Initialize the bootmem system and give it all the memory we 41 * have available. 42 */ 43 unsigned long memory_start; 44 EXPORT_SYMBOL(memory_start); 45 unsigned long memory_end; /* due to mm/nommu.c */ 46 unsigned long memory_size; 47 48 /* 49 * paging_init() sets up the page tables - in fact we've already done this. 50 */ 51 static void __init paging_init(void) 52 { 53 unsigned long zones_size[MAX_NR_ZONES]; 54 55 /* Clean every zones */ 56 memset(zones_size, 0, sizeof(zones_size)); 57 58 /* 59 * old: we can DMA to/from any address.put all page into ZONE_DMA 60 * We use only ZONE_NORMAL 61 */ 62 zones_size[ZONE_NORMAL] = max_mapnr; 63 64 free_area_init(zones_size); 65 } 66 67 void __init setup_memory(void) 68 { 69 int i; 70 unsigned long map_size; 71 #ifndef CONFIG_MMU 72 u32 kernel_align_start, kernel_align_size; 73 74 /* Find main memory where is the kernel */ 75 for (i = 0; i < lmb.memory.cnt; i++) { 76 memory_start = (u32) lmb.memory.region[i].base; 77 memory_end = (u32) lmb.memory.region[i].base 78 + (u32) lmb.memory.region[i].size; 79 if ((memory_start <= (u32)_text) && 80 ((u32)_text <= memory_end)) { 81 memory_size = memory_end - memory_start; 82 PAGE_OFFSET = memory_start; 83 printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, " 84 "size 0x%08x\n", __func__, (u32) memory_start, 85 (u32) memory_end, (u32) memory_size); 86 break; 87 } 88 } 89 90 if (!memory_start || !memory_end) { 91 panic("%s: Missing memory setting 0x%08x-0x%08x\n", 92 __func__, (u32) memory_start, (u32) memory_end); 93 } 94 95 /* reservation of region where is the kernel */ 96 kernel_align_start = PAGE_DOWN((u32)_text); 97 /* ALIGN can be remove because _end in vmlinux.lds.S is align */ 98 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; 99 lmb_reserve(kernel_align_start, kernel_align_size); 100 printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n", 101 __func__, kernel_align_start, kernel_align_start 102 + kernel_align_size, kernel_align_size); 103 104 #endif 105 /* 106 * Kernel: 107 * start: base phys address of kernel - page align 108 * end: base phys address of kernel - page align 109 * 110 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) 111 * max_low_pfn 112 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) 113 * num_physpages - number of all pages 114 */ 115 116 /* memory start is from the kernel end (aligned) to higher addr */ 117 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ 118 /* RAM is assumed contiguous */ 119 num_physpages = max_mapnr = memory_size >> PAGE_SHIFT; 120 max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT; 121 122 printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr); 123 printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); 124 printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); 125 126 /* 127 * Find an area to use for the bootmem bitmap. 128 * We look for the first area which is at least 129 * 128kB in length (128kB is enough for a bitmap 130 * for 4GB of memory, using 4kB pages), plus 1 page 131 * (in case the address isn't page-aligned). 132 */ 133 #ifndef CONFIG_MMU 134 map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)klimit)), 135 min_low_pfn, max_low_pfn); 136 #else 137 map_size = init_bootmem_node(&contig_page_data, 138 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn); 139 #endif 140 lmb_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size); 141 142 /* free bootmem is whole main memory */ 143 free_bootmem(memory_start, memory_size); 144 145 /* reserve allocate blocks */ 146 for (i = 0; i < lmb.reserved.cnt; i++) { 147 pr_debug("reserved %d - 0x%08x-0x%08x\n", i, 148 (u32) lmb.reserved.region[i].base, 149 (u32) lmb_size_bytes(&lmb.reserved, i)); 150 reserve_bootmem(lmb.reserved.region[i].base, 151 lmb_size_bytes(&lmb.reserved, i) - 1, BOOTMEM_DEFAULT); 152 } 153 #ifdef CONFIG_MMU 154 init_bootmem_done = 1; 155 #endif 156 paging_init(); 157 } 158 159 void free_init_pages(char *what, unsigned long begin, unsigned long end) 160 { 161 unsigned long addr; 162 163 for (addr = begin; addr < end; addr += PAGE_SIZE) { 164 ClearPageReserved(virt_to_page(addr)); 165 init_page_count(virt_to_page(addr)); 166 memset((void *)addr, 0xcc, PAGE_SIZE); 167 free_page(addr); 168 totalram_pages++; 169 } 170 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 171 } 172 173 #ifdef CONFIG_BLK_DEV_INITRD 174 void free_initrd_mem(unsigned long start, unsigned long end) 175 { 176 int pages = 0; 177 for (; start < end; start += PAGE_SIZE) { 178 ClearPageReserved(virt_to_page(start)); 179 init_page_count(virt_to_page(start)); 180 free_page(start); 181 totalram_pages++; 182 pages++; 183 } 184 printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n", 185 (int)(pages * (PAGE_SIZE / 1024))); 186 } 187 #endif 188 189 void free_initmem(void) 190 { 191 free_init_pages("unused kernel memory", 192 (unsigned long)(&__init_begin), 193 (unsigned long)(&__init_end)); 194 } 195 196 /* FIXME from arch/powerpc/mm/mem.c*/ 197 void show_mem(void) 198 { 199 printk(KERN_NOTICE "%s\n", __func__); 200 } 201 202 void __init mem_init(void) 203 { 204 high_memory = (void *)__va(memory_end); 205 /* this will put all memory onto the freelists */ 206 totalram_pages += free_all_bootmem(); 207 208 printk(KERN_INFO "Memory: %luk/%luk available\n", 209 nr_free_pages() << (PAGE_SHIFT-10), 210 num_physpages << (PAGE_SHIFT-10)); 211 #ifdef CONFIG_MMU 212 mem_init_done = 1; 213 #endif 214 } 215 216 #ifndef CONFIG_MMU 217 /* Check against bounds of physical memory */ 218 int ___range_ok(unsigned long addr, unsigned long size) 219 { 220 return ((addr < memory_start) || 221 ((addr + size) > memory_end)); 222 } 223 EXPORT_SYMBOL(___range_ok); 224 225 #else 226 int page_is_ram(unsigned long pfn) 227 { 228 return pfn < max_low_pfn; 229 } 230 231 /* 232 * Check for command-line options that affect what MMU_init will do. 233 */ 234 static void mm_cmdline_setup(void) 235 { 236 unsigned long maxmem = 0; 237 char *p = cmd_line; 238 239 /* Look for mem= option on command line */ 240 p = strstr(cmd_line, "mem="); 241 if (p) { 242 p += 4; 243 maxmem = memparse(p, &p); 244 if (maxmem && memory_size > maxmem) { 245 memory_size = maxmem; 246 memory_end = memory_start + memory_size; 247 lmb.memory.region[0].size = memory_size; 248 } 249 } 250 } 251 252 /* 253 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 254 */ 255 static void __init mmu_init_hw(void) 256 { 257 /* 258 * The Zone Protection Register (ZPR) defines how protection will 259 * be applied to every page which is a member of a given zone. At 260 * present, we utilize only two of the zones. 261 * The zone index bits (of ZSEL) in the PTE are used for software 262 * indicators, except the LSB. For user access, zone 1 is used, 263 * for kernel access, zone 0 is used. We set all but zone 1 264 * to zero, allowing only kernel access as indicated in the PTE. 265 * For zone 1, we set a 01 binary (a value of 10 will not work) 266 * to allow user access as indicated in the PTE. This also allows 267 * kernel access as indicated in the PTE. 268 */ 269 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 270 "mts rzpr, r11;" 271 : : : "r11"); 272 } 273 274 /* 275 * MMU_init sets up the basic memory mappings for the kernel, 276 * including both RAM and possibly some I/O regions, 277 * and sets up the page tables and the MMU hardware ready to go. 278 */ 279 280 /* called from head.S */ 281 asmlinkage void __init mmu_init(void) 282 { 283 unsigned int kstart, ksize; 284 285 if (!lmb.reserved.cnt) { 286 printk(KERN_EMERG "Error memory count\n"); 287 machine_restart(NULL); 288 } 289 290 if ((u32) lmb.memory.region[0].size < 0x1000000) { 291 printk(KERN_EMERG "Memory must be greater than 16MB\n"); 292 machine_restart(NULL); 293 } 294 /* Find main memory where the kernel is */ 295 memory_start = (u32) lmb.memory.region[0].base; 296 memory_end = (u32) lmb.memory.region[0].base + 297 (u32) lmb.memory.region[0].size; 298 memory_size = memory_end - memory_start; 299 300 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 301 302 /* 303 * Map out the kernel text/data/bss from the available physical 304 * memory. 305 */ 306 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 307 /* kernel size */ 308 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 309 lmb_reserve(kstart, ksize); 310 311 #if defined(CONFIG_BLK_DEV_INITRD) 312 /* Remove the init RAM disk from the available memory. */ 313 /* if (initrd_start) { 314 mem_pieces_remove(&phys_avail, __pa(initrd_start), 315 initrd_end - initrd_start, 1); 316 }*/ 317 #endif /* CONFIG_BLK_DEV_INITRD */ 318 319 /* Initialize the MMU hardware */ 320 mmu_init_hw(); 321 322 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 323 mapin_ram(); 324 325 #ifdef HIGHMEM_START_BOOL 326 ioremap_base = HIGHMEM_START; 327 #else 328 ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ 329 #endif /* CONFIG_HIGHMEM */ 330 ioremap_bot = ioremap_base; 331 332 /* Initialize the context management stuff */ 333 mmu_context_init(); 334 } 335 336 /* This is only called until mem_init is done. */ 337 void __init *early_get_page(void) 338 { 339 void *p; 340 if (init_bootmem_done) { 341 p = alloc_bootmem_pages(PAGE_SIZE); 342 } else { 343 /* 344 * Mem start + 32MB -> here is limit 345 * because of mem mapping from head.S 346 */ 347 p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE, 348 memory_start + 0x2000000)); 349 } 350 return p; 351 } 352 #endif /* CONFIG_MMU */ 353