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-contiguous.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 #ifdef CONFIG_HIGHMEM 50 pte_t *kmap_pte; 51 EXPORT_SYMBOL(kmap_pte); 52 53 static void __init highmem_init(void) 54 { 55 pr_debug("%x\n", (u32)PKMAP_BASE); 56 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 57 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 58 59 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); 60 } 61 62 static void highmem_setup(void) 63 { 64 unsigned long pfn; 65 66 for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) { 67 struct page *page = pfn_to_page(pfn); 68 69 /* FIXME not sure about */ 70 if (!memblock_is_reserved(pfn << PAGE_SHIFT)) 71 free_highmem_page(page); 72 } 73 } 74 #endif /* CONFIG_HIGHMEM */ 75 76 /* 77 * paging_init() sets up the page tables - in fact we've already done this. 78 */ 79 static void __init paging_init(void) 80 { 81 unsigned long zones_size[MAX_NR_ZONES]; 82 #ifdef CONFIG_MMU 83 int idx; 84 85 /* Setup fixmaps */ 86 for (idx = 0; idx < __end_of_fixed_addresses; idx++) 87 clear_fixmap(idx); 88 #endif 89 90 /* Clean every zones */ 91 memset(zones_size, 0, sizeof(zones_size)); 92 93 #ifdef CONFIG_HIGHMEM 94 highmem_init(); 95 96 zones_size[ZONE_DMA] = max_low_pfn; 97 zones_size[ZONE_HIGHMEM] = max_pfn; 98 #else 99 zones_size[ZONE_DMA] = max_pfn; 100 #endif 101 102 /* We don't have holes in memory map */ 103 free_area_init(zones_size); 104 } 105 106 void __init setup_memory(void) 107 { 108 struct memblock_region *reg; 109 110 #ifndef CONFIG_MMU 111 u32 kernel_align_start, kernel_align_size; 112 113 /* Find main memory where is the kernel */ 114 for_each_memblock(memory, reg) { 115 memory_start = (u32)reg->base; 116 lowmem_size = reg->size; 117 if ((memory_start <= (u32)_text) && 118 ((u32)_text <= (memory_start + lowmem_size - 1))) { 119 memory_size = lowmem_size; 120 PAGE_OFFSET = memory_start; 121 pr_info("%s: Main mem: 0x%x, size 0x%08x\n", 122 __func__, (u32) memory_start, 123 (u32) memory_size); 124 break; 125 } 126 } 127 128 if (!memory_start || !memory_size) { 129 panic("%s: Missing memory setting 0x%08x, size=0x%08x\n", 130 __func__, (u32) memory_start, (u32) memory_size); 131 } 132 133 /* reservation of region where is the kernel */ 134 kernel_align_start = PAGE_DOWN((u32)_text); 135 /* ALIGN can be remove because _end in vmlinux.lds.S is align */ 136 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; 137 pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n", 138 __func__, kernel_align_start, kernel_align_start 139 + kernel_align_size, kernel_align_size); 140 memblock_reserve(kernel_align_start, kernel_align_size); 141 #endif 142 /* 143 * Kernel: 144 * start: base phys address of kernel - page align 145 * end: base phys address of kernel - page align 146 * 147 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) 148 * max_low_pfn 149 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) 150 */ 151 152 /* memory start is from the kernel end (aligned) to higher addr */ 153 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ 154 /* RAM is assumed contiguous */ 155 max_mapnr = memory_size >> PAGE_SHIFT; 156 max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT; 157 max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT; 158 159 pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr); 160 pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); 161 pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); 162 pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn); 163 164 /* Add active regions with valid PFNs */ 165 for_each_memblock(memory, reg) { 166 unsigned long start_pfn, end_pfn; 167 168 start_pfn = memblock_region_memory_base_pfn(reg); 169 end_pfn = memblock_region_memory_end_pfn(reg); 170 memblock_set_node(start_pfn << PAGE_SHIFT, 171 (end_pfn - start_pfn) << PAGE_SHIFT, 172 &memblock.memory, 0); 173 } 174 175 paging_init(); 176 } 177 178 void __init mem_init(void) 179 { 180 high_memory = (void *)__va(memory_start + lowmem_size - 1); 181 182 /* this will put all memory onto the freelists */ 183 memblock_free_all(); 184 #ifdef CONFIG_HIGHMEM 185 highmem_setup(); 186 #endif 187 188 mem_init_print_info(NULL); 189 mem_init_done = 1; 190 } 191 192 #ifndef CONFIG_MMU 193 int page_is_ram(unsigned long pfn) 194 { 195 return __range_ok(pfn, 0); 196 } 197 #else 198 int page_is_ram(unsigned long pfn) 199 { 200 return pfn < max_low_pfn; 201 } 202 203 /* 204 * Check for command-line options that affect what MMU_init will do. 205 */ 206 static void mm_cmdline_setup(void) 207 { 208 unsigned long maxmem = 0; 209 char *p = cmd_line; 210 211 /* Look for mem= option on command line */ 212 p = strstr(cmd_line, "mem="); 213 if (p) { 214 p += 4; 215 maxmem = memparse(p, &p); 216 if (maxmem && memory_size > maxmem) { 217 memory_size = maxmem; 218 memblock.memory.regions[0].size = memory_size; 219 } 220 } 221 } 222 223 /* 224 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 225 */ 226 static void __init mmu_init_hw(void) 227 { 228 /* 229 * The Zone Protection Register (ZPR) defines how protection will 230 * be applied to every page which is a member of a given zone. At 231 * present, we utilize only two of the zones. 232 * The zone index bits (of ZSEL) in the PTE are used for software 233 * indicators, except the LSB. For user access, zone 1 is used, 234 * for kernel access, zone 0 is used. We set all but zone 1 235 * to zero, allowing only kernel access as indicated in the PTE. 236 * For zone 1, we set a 01 binary (a value of 10 will not work) 237 * to allow user access as indicated in the PTE. This also allows 238 * kernel access as indicated in the PTE. 239 */ 240 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 241 "mts rzpr, r11;" 242 : : : "r11"); 243 } 244 245 /* 246 * MMU_init sets up the basic memory mappings for the kernel, 247 * including both RAM and possibly some I/O regions, 248 * and sets up the page tables and the MMU hardware ready to go. 249 */ 250 251 /* called from head.S */ 252 asmlinkage void __init mmu_init(void) 253 { 254 unsigned int kstart, ksize; 255 256 if (!memblock.reserved.cnt) { 257 pr_emerg("Error memory count\n"); 258 machine_restart(NULL); 259 } 260 261 if ((u32) memblock.memory.regions[0].size < 0x400000) { 262 pr_emerg("Memory must be greater than 4MB\n"); 263 machine_restart(NULL); 264 } 265 266 if ((u32) memblock.memory.regions[0].size < kernel_tlb) { 267 pr_emerg("Kernel size is greater than memory node\n"); 268 machine_restart(NULL); 269 } 270 271 /* Find main memory where the kernel is */ 272 memory_start = (u32) memblock.memory.regions[0].base; 273 lowmem_size = memory_size = (u32) memblock.memory.regions[0].size; 274 275 if (lowmem_size > CONFIG_LOWMEM_SIZE) { 276 lowmem_size = CONFIG_LOWMEM_SIZE; 277 #ifndef CONFIG_HIGHMEM 278 memory_size = lowmem_size; 279 #endif 280 } 281 282 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 283 284 /* 285 * Map out the kernel text/data/bss from the available physical 286 * memory. 287 */ 288 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 289 /* kernel size */ 290 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 291 memblock_reserve(kstart, ksize); 292 293 #if defined(CONFIG_BLK_DEV_INITRD) 294 /* Remove the init RAM disk from the available memory. */ 295 if (initrd_start) { 296 unsigned long size; 297 size = initrd_end - initrd_start; 298 memblock_reserve(__virt_to_phys(initrd_start), size); 299 } 300 #endif /* CONFIG_BLK_DEV_INITRD */ 301 302 /* Initialize the MMU hardware */ 303 mmu_init_hw(); 304 305 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 306 mapin_ram(); 307 308 /* Extend vmalloc and ioremap area as big as possible */ 309 #ifdef CONFIG_HIGHMEM 310 ioremap_base = ioremap_bot = PKMAP_BASE; 311 #else 312 ioremap_base = ioremap_bot = FIXADDR_START; 313 #endif 314 315 /* Initialize the context management stuff */ 316 mmu_context_init(); 317 318 /* Shortly after that, the entire linear mapping will be available */ 319 /* This will also cause that unflatten device tree will be allocated 320 * inside 768MB limit */ 321 memblock_set_current_limit(memory_start + lowmem_size - 1); 322 323 parse_early_param(); 324 325 /* CMA initialization */ 326 dma_contiguous_reserve(memory_start + lowmem_size - 1); 327 } 328 329 /* This is only called until mem_init is done. */ 330 void __init *early_get_page(void) 331 { 332 /* 333 * Mem start + kernel_tlb -> here is limit 334 * because of mem mapping from head.S 335 */ 336 return memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE, 337 MEMBLOCK_LOW_LIMIT, memory_start + kernel_tlb, 338 NUMA_NO_NODE); 339 } 340 341 #endif /* CONFIG_MMU */ 342 343 void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask) 344 { 345 void *p; 346 347 if (mem_init_done) { 348 p = kzalloc(size, mask); 349 } else { 350 p = memblock_alloc(size, SMP_CACHE_BYTES); 351 if (!p) 352 panic("%s: Failed to allocate %zu bytes\n", 353 __func__, size); 354 } 355 356 return p; 357 } 358