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