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 pgprot_t kmap_prot; 53 EXPORT_SYMBOL(kmap_prot); 54 55 static inline pte_t *virt_to_kpte(unsigned long vaddr) 56 { 57 pgd_t *pgd = pgd_offset_k(vaddr); 58 p4d_t *p4d = p4d_offset(pgd, vaddr); 59 pud_t *pud = pud_offset(p4d, vaddr); 60 61 return pte_offset_kernel(pmd_offset(pud, vaddr), vaddr); 62 } 63 64 static void __init highmem_init(void) 65 { 66 pr_debug("%x\n", (u32)PKMAP_BASE); 67 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 68 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 69 70 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); 71 kmap_prot = PAGE_KERNEL; 72 } 73 74 static void highmem_setup(void) 75 { 76 unsigned long pfn; 77 78 for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) { 79 struct page *page = pfn_to_page(pfn); 80 81 /* FIXME not sure about */ 82 if (!memblock_is_reserved(pfn << PAGE_SHIFT)) 83 free_highmem_page(page); 84 } 85 } 86 #endif /* CONFIG_HIGHMEM */ 87 88 /* 89 * paging_init() sets up the page tables - in fact we've already done this. 90 */ 91 static void __init paging_init(void) 92 { 93 unsigned long zones_size[MAX_NR_ZONES]; 94 #ifdef CONFIG_MMU 95 int idx; 96 97 /* Setup fixmaps */ 98 for (idx = 0; idx < __end_of_fixed_addresses; idx++) 99 clear_fixmap(idx); 100 #endif 101 102 /* Clean every zones */ 103 memset(zones_size, 0, sizeof(zones_size)); 104 105 #ifdef CONFIG_HIGHMEM 106 highmem_init(); 107 108 zones_size[ZONE_DMA] = max_low_pfn; 109 zones_size[ZONE_HIGHMEM] = max_pfn; 110 #else 111 zones_size[ZONE_DMA] = max_pfn; 112 #endif 113 114 /* We don't have holes in memory map */ 115 free_area_init_nodes(zones_size); 116 } 117 118 void __init setup_memory(void) 119 { 120 struct memblock_region *reg; 121 122 #ifndef CONFIG_MMU 123 u32 kernel_align_start, kernel_align_size; 124 125 /* Find main memory where is the kernel */ 126 for_each_memblock(memory, reg) { 127 memory_start = (u32)reg->base; 128 lowmem_size = reg->size; 129 if ((memory_start <= (u32)_text) && 130 ((u32)_text <= (memory_start + lowmem_size - 1))) { 131 memory_size = lowmem_size; 132 PAGE_OFFSET = memory_start; 133 pr_info("%s: Main mem: 0x%x, size 0x%08x\n", 134 __func__, (u32) memory_start, 135 (u32) memory_size); 136 break; 137 } 138 } 139 140 if (!memory_start || !memory_size) { 141 panic("%s: Missing memory setting 0x%08x, size=0x%08x\n", 142 __func__, (u32) memory_start, (u32) memory_size); 143 } 144 145 /* reservation of region where is the kernel */ 146 kernel_align_start = PAGE_DOWN((u32)_text); 147 /* ALIGN can be remove because _end in vmlinux.lds.S is align */ 148 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; 149 pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n", 150 __func__, kernel_align_start, kernel_align_start 151 + kernel_align_size, kernel_align_size); 152 memblock_reserve(kernel_align_start, kernel_align_size); 153 #endif 154 /* 155 * Kernel: 156 * start: base phys address of kernel - page align 157 * end: base phys address of kernel - page align 158 * 159 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) 160 * max_low_pfn 161 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) 162 */ 163 164 /* memory start is from the kernel end (aligned) to higher addr */ 165 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ 166 /* RAM is assumed contiguous */ 167 max_mapnr = memory_size >> PAGE_SHIFT; 168 max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT; 169 max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT; 170 171 pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr); 172 pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); 173 pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); 174 pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn); 175 176 /* Add active regions with valid PFNs */ 177 for_each_memblock(memory, reg) { 178 unsigned long start_pfn, end_pfn; 179 180 start_pfn = memblock_region_memory_base_pfn(reg); 181 end_pfn = memblock_region_memory_end_pfn(reg); 182 memblock_set_node(start_pfn << PAGE_SHIFT, 183 (end_pfn - start_pfn) << PAGE_SHIFT, 184 &memblock.memory, 0); 185 } 186 187 /* XXX need to clip this if using highmem? */ 188 sparse_memory_present_with_active_regions(0); 189 190 paging_init(); 191 } 192 193 void __init mem_init(void) 194 { 195 high_memory = (void *)__va(memory_start + lowmem_size - 1); 196 197 /* this will put all memory onto the freelists */ 198 memblock_free_all(); 199 #ifdef CONFIG_HIGHMEM 200 highmem_setup(); 201 #endif 202 203 mem_init_print_info(NULL); 204 #ifdef CONFIG_MMU 205 pr_info("Kernel virtual memory layout:\n"); 206 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); 207 #ifdef CONFIG_HIGHMEM 208 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", 209 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); 210 #endif /* CONFIG_HIGHMEM */ 211 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", 212 ioremap_bot, ioremap_base); 213 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", 214 (unsigned long)VMALLOC_START, VMALLOC_END); 215 #endif 216 mem_init_done = 1; 217 } 218 219 #ifndef CONFIG_MMU 220 int page_is_ram(unsigned long pfn) 221 { 222 return __range_ok(pfn, 0); 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 memblock.memory.regions[0].size = memory_size; 246 } 247 } 248 } 249 250 /* 251 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 252 */ 253 static void __init mmu_init_hw(void) 254 { 255 /* 256 * The Zone Protection Register (ZPR) defines how protection will 257 * be applied to every page which is a member of a given zone. At 258 * present, we utilize only two of the zones. 259 * The zone index bits (of ZSEL) in the PTE are used for software 260 * indicators, except the LSB. For user access, zone 1 is used, 261 * for kernel access, zone 0 is used. We set all but zone 1 262 * to zero, allowing only kernel access as indicated in the PTE. 263 * For zone 1, we set a 01 binary (a value of 10 will not work) 264 * to allow user access as indicated in the PTE. This also allows 265 * kernel access as indicated in the PTE. 266 */ 267 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 268 "mts rzpr, r11;" 269 : : : "r11"); 270 } 271 272 /* 273 * MMU_init sets up the basic memory mappings for the kernel, 274 * including both RAM and possibly some I/O regions, 275 * and sets up the page tables and the MMU hardware ready to go. 276 */ 277 278 /* called from head.S */ 279 asmlinkage void __init mmu_init(void) 280 { 281 unsigned int kstart, ksize; 282 283 if (!memblock.reserved.cnt) { 284 pr_emerg("Error memory count\n"); 285 machine_restart(NULL); 286 } 287 288 if ((u32) memblock.memory.regions[0].size < 0x400000) { 289 pr_emerg("Memory must be greater than 4MB\n"); 290 machine_restart(NULL); 291 } 292 293 if ((u32) memblock.memory.regions[0].size < kernel_tlb) { 294 pr_emerg("Kernel size is greater than memory node\n"); 295 machine_restart(NULL); 296 } 297 298 /* Find main memory where the kernel is */ 299 memory_start = (u32) memblock.memory.regions[0].base; 300 lowmem_size = memory_size = (u32) memblock.memory.regions[0].size; 301 302 if (lowmem_size > CONFIG_LOWMEM_SIZE) { 303 lowmem_size = CONFIG_LOWMEM_SIZE; 304 #ifndef CONFIG_HIGHMEM 305 memory_size = lowmem_size; 306 #endif 307 } 308 309 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 310 311 /* 312 * Map out the kernel text/data/bss from the available physical 313 * memory. 314 */ 315 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 316 /* kernel size */ 317 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 318 memblock_reserve(kstart, ksize); 319 320 #if defined(CONFIG_BLK_DEV_INITRD) 321 /* Remove the init RAM disk from the available memory. */ 322 if (initrd_start) { 323 unsigned long size; 324 size = initrd_end - initrd_start; 325 memblock_reserve(__virt_to_phys(initrd_start), size); 326 } 327 #endif /* CONFIG_BLK_DEV_INITRD */ 328 329 /* Initialize the MMU hardware */ 330 mmu_init_hw(); 331 332 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 333 mapin_ram(); 334 335 /* Extend vmalloc and ioremap area as big as possible */ 336 #ifdef CONFIG_HIGHMEM 337 ioremap_base = ioremap_bot = PKMAP_BASE; 338 #else 339 ioremap_base = ioremap_bot = FIXADDR_START; 340 #endif 341 342 /* Initialize the context management stuff */ 343 mmu_context_init(); 344 345 /* Shortly after that, the entire linear mapping will be available */ 346 /* This will also cause that unflatten device tree will be allocated 347 * inside 768MB limit */ 348 memblock_set_current_limit(memory_start + lowmem_size - 1); 349 350 /* CMA initialization */ 351 dma_contiguous_reserve(memory_start + lowmem_size - 1); 352 } 353 354 /* This is only called until mem_init is done. */ 355 void __init *early_get_page(void) 356 { 357 /* 358 * Mem start + kernel_tlb -> here is limit 359 * because of mem mapping from head.S 360 */ 361 return memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE, 362 MEMBLOCK_LOW_LIMIT, memory_start + kernel_tlb, 363 NUMA_NO_NODE); 364 } 365 366 #endif /* CONFIG_MMU */ 367 368 void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask) 369 { 370 void *p; 371 372 if (mem_init_done) { 373 p = kzalloc(size, mask); 374 } else { 375 p = memblock_alloc(size, SMP_CACHE_BYTES); 376 if (!p) 377 panic("%s: Failed to allocate %zu bytes\n", 378 __func__, size); 379 } 380 381 return p; 382 } 383