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