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/dma-map-ops.h> 11 #include <linux/memblock.h> 12 #include <linux/init.h> 13 #include <linux/kernel.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 #include <linux/export.h> 21 22 #include <asm/page.h> 23 #include <asm/mmu_context.h> 24 #include <asm/pgalloc.h> 25 #include <asm/sections.h> 26 #include <asm/tlb.h> 27 #include <asm/fixmap.h> 28 29 /* Use for MMU and noMMU because of PCI generic code */ 30 int mem_init_done; 31 32 #ifndef CONFIG_MMU 33 unsigned int __page_offset; 34 EXPORT_SYMBOL(__page_offset); 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_size; 46 EXPORT_SYMBOL(memory_size); 47 unsigned long lowmem_size; 48 49 EXPORT_SYMBOL(min_low_pfn); 50 EXPORT_SYMBOL(max_low_pfn); 51 52 #ifdef CONFIG_HIGHMEM 53 pte_t *kmap_pte; 54 EXPORT_SYMBOL(kmap_pte); 55 56 static void __init highmem_init(void) 57 { 58 pr_debug("%x\n", (u32)PKMAP_BASE); 59 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 60 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 61 62 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); 63 } 64 65 static void highmem_setup(void) 66 { 67 unsigned long pfn; 68 69 for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) { 70 struct page *page = pfn_to_page(pfn); 71 72 /* FIXME not sure about */ 73 if (!memblock_is_reserved(pfn << PAGE_SHIFT)) 74 free_highmem_page(page); 75 } 76 } 77 #endif /* CONFIG_HIGHMEM */ 78 79 /* 80 * paging_init() sets up the page tables - in fact we've already done this. 81 */ 82 static void __init paging_init(void) 83 { 84 unsigned long zones_size[MAX_NR_ZONES]; 85 #ifdef CONFIG_MMU 86 int idx; 87 88 /* Setup fixmaps */ 89 for (idx = 0; idx < __end_of_fixed_addresses; idx++) 90 clear_fixmap(idx); 91 #endif 92 93 /* Clean every zones */ 94 memset(zones_size, 0, sizeof(zones_size)); 95 96 #ifdef CONFIG_HIGHMEM 97 highmem_init(); 98 99 zones_size[ZONE_DMA] = max_low_pfn; 100 zones_size[ZONE_HIGHMEM] = max_pfn; 101 #else 102 zones_size[ZONE_DMA] = max_pfn; 103 #endif 104 105 /* We don't have holes in memory map */ 106 free_area_init(zones_size); 107 } 108 109 void __init setup_memory(void) 110 { 111 #ifndef CONFIG_MMU 112 u32 kernel_align_start, kernel_align_size; 113 phys_addr_t start, end; 114 u64 i; 115 116 /* Find main memory where is the kernel */ 117 for_each_mem_range(i, &start, &end) { 118 memory_start = start; 119 lowmem_size = end - start; 120 if ((memory_start <= (u32)_text) && 121 ((u32)_text <= (memory_start + lowmem_size - 1))) { 122 memory_size = lowmem_size; 123 PAGE_OFFSET = memory_start; 124 pr_info("%s: Main mem: 0x%x, size 0x%08x\n", 125 __func__, (u32) memory_start, 126 (u32) memory_size); 127 break; 128 } 129 } 130 131 if (!memory_start || !memory_size) { 132 panic("%s: Missing memory setting 0x%08x, size=0x%08x\n", 133 __func__, (u32) memory_start, (u32) memory_size); 134 } 135 136 /* reservation of region where is the kernel */ 137 kernel_align_start = PAGE_DOWN((u32)_text); 138 /* ALIGN can be remove because _end in vmlinux.lds.S is align */ 139 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; 140 pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n", 141 __func__, kernel_align_start, kernel_align_start 142 + kernel_align_size, kernel_align_size); 143 memblock_reserve(kernel_align_start, kernel_align_size); 144 #endif 145 /* 146 * Kernel: 147 * start: base phys address of kernel - page align 148 * end: base phys address of kernel - page align 149 * 150 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) 151 * max_low_pfn 152 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) 153 */ 154 155 /* memory start is from the kernel end (aligned) to higher addr */ 156 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ 157 /* RAM is assumed contiguous */ 158 max_mapnr = memory_size >> PAGE_SHIFT; 159 max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT; 160 max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT; 161 162 pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr); 163 pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); 164 pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); 165 pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn); 166 167 paging_init(); 168 } 169 170 void __init mem_init(void) 171 { 172 high_memory = (void *)__va(memory_start + lowmem_size - 1); 173 174 /* this will put all memory onto the freelists */ 175 memblock_free_all(); 176 #ifdef CONFIG_HIGHMEM 177 highmem_setup(); 178 #endif 179 180 mem_init_print_info(NULL); 181 mem_init_done = 1; 182 } 183 184 #ifndef CONFIG_MMU 185 int page_is_ram(unsigned long pfn) 186 { 187 return __range_ok(pfn, 0); 188 } 189 #else 190 int page_is_ram(unsigned long pfn) 191 { 192 return pfn < max_low_pfn; 193 } 194 195 /* 196 * Check for command-line options that affect what MMU_init will do. 197 */ 198 static void mm_cmdline_setup(void) 199 { 200 unsigned long maxmem = 0; 201 char *p = cmd_line; 202 203 /* Look for mem= option on command line */ 204 p = strstr(cmd_line, "mem="); 205 if (p) { 206 p += 4; 207 maxmem = memparse(p, &p); 208 if (maxmem && memory_size > maxmem) { 209 memory_size = maxmem; 210 memblock.memory.regions[0].size = memory_size; 211 } 212 } 213 } 214 215 /* 216 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 217 */ 218 static void __init mmu_init_hw(void) 219 { 220 /* 221 * The Zone Protection Register (ZPR) defines how protection will 222 * be applied to every page which is a member of a given zone. At 223 * present, we utilize only two of the zones. 224 * The zone index bits (of ZSEL) in the PTE are used for software 225 * indicators, except the LSB. For user access, zone 1 is used, 226 * for kernel access, zone 0 is used. We set all but zone 1 227 * to zero, allowing only kernel access as indicated in the PTE. 228 * For zone 1, we set a 01 binary (a value of 10 will not work) 229 * to allow user access as indicated in the PTE. This also allows 230 * kernel access as indicated in the PTE. 231 */ 232 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 233 "mts rzpr, r11;" 234 : : : "r11"); 235 } 236 237 /* 238 * MMU_init sets up the basic memory mappings for the kernel, 239 * including both RAM and possibly some I/O regions, 240 * and sets up the page tables and the MMU hardware ready to go. 241 */ 242 243 /* called from head.S */ 244 asmlinkage void __init mmu_init(void) 245 { 246 unsigned int kstart, ksize; 247 248 if (!memblock.reserved.cnt) { 249 pr_emerg("Error memory count\n"); 250 machine_restart(NULL); 251 } 252 253 if ((u32) memblock.memory.regions[0].size < 0x400000) { 254 pr_emerg("Memory must be greater than 4MB\n"); 255 machine_restart(NULL); 256 } 257 258 if ((u32) memblock.memory.regions[0].size < kernel_tlb) { 259 pr_emerg("Kernel size is greater than memory node\n"); 260 machine_restart(NULL); 261 } 262 263 /* Find main memory where the kernel is */ 264 memory_start = (u32) memblock.memory.regions[0].base; 265 lowmem_size = memory_size = (u32) memblock.memory.regions[0].size; 266 267 if (lowmem_size > CONFIG_LOWMEM_SIZE) { 268 lowmem_size = CONFIG_LOWMEM_SIZE; 269 #ifndef CONFIG_HIGHMEM 270 memory_size = lowmem_size; 271 #endif 272 } 273 274 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 275 276 /* 277 * Map out the kernel text/data/bss from the available physical 278 * memory. 279 */ 280 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 281 /* kernel size */ 282 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 283 memblock_reserve(kstart, ksize); 284 285 #if defined(CONFIG_BLK_DEV_INITRD) 286 /* Remove the init RAM disk from the available memory. */ 287 if (initrd_start) { 288 unsigned long size; 289 size = initrd_end - initrd_start; 290 memblock_reserve(__virt_to_phys(initrd_start), size); 291 } 292 #endif /* CONFIG_BLK_DEV_INITRD */ 293 294 /* Initialize the MMU hardware */ 295 mmu_init_hw(); 296 297 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 298 mapin_ram(); 299 300 /* Extend vmalloc and ioremap area as big as possible */ 301 #ifdef CONFIG_HIGHMEM 302 ioremap_base = ioremap_bot = PKMAP_BASE; 303 #else 304 ioremap_base = ioremap_bot = FIXADDR_START; 305 #endif 306 307 /* Initialize the context management stuff */ 308 mmu_context_init(); 309 310 /* Shortly after that, the entire linear mapping will be available */ 311 /* This will also cause that unflatten device tree will be allocated 312 * inside 768MB limit */ 313 memblock_set_current_limit(memory_start + lowmem_size - 1); 314 315 parse_early_param(); 316 317 /* CMA initialization */ 318 dma_contiguous_reserve(memory_start + lowmem_size - 1); 319 } 320 321 /* This is only called until mem_init is done. */ 322 void __init *early_get_page(void) 323 { 324 /* 325 * Mem start + kernel_tlb -> here is limit 326 * because of mem mapping from head.S 327 */ 328 return memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE, 329 MEMBLOCK_LOW_LIMIT, memory_start + kernel_tlb, 330 NUMA_NO_NODE); 331 } 332 333 #endif /* CONFIG_MMU */ 334 335 void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask) 336 { 337 void *p; 338 339 if (mem_init_done) { 340 p = kzalloc(size, mask); 341 } else { 342 p = memblock_alloc(size, SMP_CACHE_BYTES); 343 if (!p) 344 panic("%s: Failed to allocate %zu bytes\n", 345 __func__, size); 346 } 347 348 return p; 349 } 350