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 inline pte_t *virt_to_kpte(unsigned long vaddr) 54 { 55 pgd_t *pgd = pgd_offset_k(vaddr); 56 p4d_t *p4d = p4d_offset(pgd, vaddr); 57 pud_t *pud = pud_offset(p4d, vaddr); 58 59 return pte_offset_kernel(pmd_offset(pud, vaddr), vaddr); 60 } 61 62 static void __init highmem_init(void) 63 { 64 pr_debug("%x\n", (u32)PKMAP_BASE); 65 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 66 pkmap_page_table = virt_to_kpte(PKMAP_BASE); 67 68 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); 69 } 70 71 static void highmem_setup(void) 72 { 73 unsigned long pfn; 74 75 for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) { 76 struct page *page = pfn_to_page(pfn); 77 78 /* FIXME not sure about */ 79 if (!memblock_is_reserved(pfn << PAGE_SHIFT)) 80 free_highmem_page(page); 81 } 82 } 83 #endif /* CONFIG_HIGHMEM */ 84 85 /* 86 * paging_init() sets up the page tables - in fact we've already done this. 87 */ 88 static void __init paging_init(void) 89 { 90 unsigned long zones_size[MAX_NR_ZONES]; 91 #ifdef CONFIG_MMU 92 int idx; 93 94 /* Setup fixmaps */ 95 for (idx = 0; idx < __end_of_fixed_addresses; idx++) 96 clear_fixmap(idx); 97 #endif 98 99 /* Clean every zones */ 100 memset(zones_size, 0, sizeof(zones_size)); 101 102 #ifdef CONFIG_HIGHMEM 103 highmem_init(); 104 105 zones_size[ZONE_DMA] = max_low_pfn; 106 zones_size[ZONE_HIGHMEM] = max_pfn; 107 #else 108 zones_size[ZONE_DMA] = max_pfn; 109 #endif 110 111 /* We don't have holes in memory map */ 112 free_area_init(zones_size); 113 } 114 115 void __init setup_memory(void) 116 { 117 struct memblock_region *reg; 118 119 #ifndef CONFIG_MMU 120 u32 kernel_align_start, kernel_align_size; 121 122 /* Find main memory where is the kernel */ 123 for_each_memblock(memory, reg) { 124 memory_start = (u32)reg->base; 125 lowmem_size = reg->size; 126 if ((memory_start <= (u32)_text) && 127 ((u32)_text <= (memory_start + lowmem_size - 1))) { 128 memory_size = lowmem_size; 129 PAGE_OFFSET = memory_start; 130 pr_info("%s: Main mem: 0x%x, size 0x%08x\n", 131 __func__, (u32) memory_start, 132 (u32) memory_size); 133 break; 134 } 135 } 136 137 if (!memory_start || !memory_size) { 138 panic("%s: Missing memory setting 0x%08x, size=0x%08x\n", 139 __func__, (u32) memory_start, (u32) memory_size); 140 } 141 142 /* reservation of region where is the kernel */ 143 kernel_align_start = PAGE_DOWN((u32)_text); 144 /* ALIGN can be remove because _end in vmlinux.lds.S is align */ 145 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; 146 pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n", 147 __func__, kernel_align_start, kernel_align_start 148 + kernel_align_size, kernel_align_size); 149 memblock_reserve(kernel_align_start, kernel_align_size); 150 #endif 151 /* 152 * Kernel: 153 * start: base phys address of kernel - page align 154 * end: base phys address of kernel - page align 155 * 156 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) 157 * max_low_pfn 158 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) 159 */ 160 161 /* memory start is from the kernel end (aligned) to higher addr */ 162 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ 163 /* RAM is assumed contiguous */ 164 max_mapnr = memory_size >> PAGE_SHIFT; 165 max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT; 166 max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT; 167 168 pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr); 169 pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); 170 pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); 171 pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn); 172 173 /* Add active regions with valid PFNs */ 174 for_each_memblock(memory, reg) { 175 unsigned long start_pfn, end_pfn; 176 177 start_pfn = memblock_region_memory_base_pfn(reg); 178 end_pfn = memblock_region_memory_end_pfn(reg); 179 memblock_set_node(start_pfn << PAGE_SHIFT, 180 (end_pfn - start_pfn) << PAGE_SHIFT, 181 &memblock.memory, 0); 182 } 183 184 /* XXX need to clip this if using highmem? */ 185 sparse_memory_present_with_active_regions(0); 186 187 paging_init(); 188 } 189 190 void __init mem_init(void) 191 { 192 high_memory = (void *)__va(memory_start + lowmem_size - 1); 193 194 /* this will put all memory onto the freelists */ 195 memblock_free_all(); 196 #ifdef CONFIG_HIGHMEM 197 highmem_setup(); 198 #endif 199 200 mem_init_print_info(NULL); 201 mem_init_done = 1; 202 } 203 204 #ifndef CONFIG_MMU 205 int page_is_ram(unsigned long pfn) 206 { 207 return __range_ok(pfn, 0); 208 } 209 #else 210 int page_is_ram(unsigned long pfn) 211 { 212 return pfn < max_low_pfn; 213 } 214 215 /* 216 * Check for command-line options that affect what MMU_init will do. 217 */ 218 static void mm_cmdline_setup(void) 219 { 220 unsigned long maxmem = 0; 221 char *p = cmd_line; 222 223 /* Look for mem= option on command line */ 224 p = strstr(cmd_line, "mem="); 225 if (p) { 226 p += 4; 227 maxmem = memparse(p, &p); 228 if (maxmem && memory_size > maxmem) { 229 memory_size = maxmem; 230 memblock.memory.regions[0].size = memory_size; 231 } 232 } 233 } 234 235 /* 236 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 237 */ 238 static void __init mmu_init_hw(void) 239 { 240 /* 241 * The Zone Protection Register (ZPR) defines how protection will 242 * be applied to every page which is a member of a given zone. At 243 * present, we utilize only two of the zones. 244 * The zone index bits (of ZSEL) in the PTE are used for software 245 * indicators, except the LSB. For user access, zone 1 is used, 246 * for kernel access, zone 0 is used. We set all but zone 1 247 * to zero, allowing only kernel access as indicated in the PTE. 248 * For zone 1, we set a 01 binary (a value of 10 will not work) 249 * to allow user access as indicated in the PTE. This also allows 250 * kernel access as indicated in the PTE. 251 */ 252 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ 253 "mts rzpr, r11;" 254 : : : "r11"); 255 } 256 257 /* 258 * MMU_init sets up the basic memory mappings for the kernel, 259 * including both RAM and possibly some I/O regions, 260 * and sets up the page tables and the MMU hardware ready to go. 261 */ 262 263 /* called from head.S */ 264 asmlinkage void __init mmu_init(void) 265 { 266 unsigned int kstart, ksize; 267 268 if (!memblock.reserved.cnt) { 269 pr_emerg("Error memory count\n"); 270 machine_restart(NULL); 271 } 272 273 if ((u32) memblock.memory.regions[0].size < 0x400000) { 274 pr_emerg("Memory must be greater than 4MB\n"); 275 machine_restart(NULL); 276 } 277 278 if ((u32) memblock.memory.regions[0].size < kernel_tlb) { 279 pr_emerg("Kernel size is greater than memory node\n"); 280 machine_restart(NULL); 281 } 282 283 /* Find main memory where the kernel is */ 284 memory_start = (u32) memblock.memory.regions[0].base; 285 lowmem_size = memory_size = (u32) memblock.memory.regions[0].size; 286 287 if (lowmem_size > CONFIG_LOWMEM_SIZE) { 288 lowmem_size = CONFIG_LOWMEM_SIZE; 289 #ifndef CONFIG_HIGHMEM 290 memory_size = lowmem_size; 291 #endif 292 } 293 294 mm_cmdline_setup(); /* FIXME parse args from command line - not used */ 295 296 /* 297 * Map out the kernel text/data/bss from the available physical 298 * memory. 299 */ 300 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ 301 /* kernel size */ 302 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); 303 memblock_reserve(kstart, ksize); 304 305 #if defined(CONFIG_BLK_DEV_INITRD) 306 /* Remove the init RAM disk from the available memory. */ 307 if (initrd_start) { 308 unsigned long size; 309 size = initrd_end - initrd_start; 310 memblock_reserve(__virt_to_phys(initrd_start), size); 311 } 312 #endif /* CONFIG_BLK_DEV_INITRD */ 313 314 /* Initialize the MMU hardware */ 315 mmu_init_hw(); 316 317 /* Map in all of RAM starting at CONFIG_KERNEL_START */ 318 mapin_ram(); 319 320 /* Extend vmalloc and ioremap area as big as possible */ 321 #ifdef CONFIG_HIGHMEM 322 ioremap_base = ioremap_bot = PKMAP_BASE; 323 #else 324 ioremap_base = ioremap_bot = FIXADDR_START; 325 #endif 326 327 /* Initialize the context management stuff */ 328 mmu_context_init(); 329 330 /* Shortly after that, the entire linear mapping will be available */ 331 /* This will also cause that unflatten device tree will be allocated 332 * inside 768MB limit */ 333 memblock_set_current_limit(memory_start + lowmem_size - 1); 334 335 parse_early_param(); 336 337 /* CMA initialization */ 338 dma_contiguous_reserve(memory_start + lowmem_size - 1); 339 } 340 341 /* This is only called until mem_init is done. */ 342 void __init *early_get_page(void) 343 { 344 /* 345 * Mem start + kernel_tlb -> here is limit 346 * because of mem mapping from head.S 347 */ 348 return memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE, 349 MEMBLOCK_LOW_LIMIT, memory_start + kernel_tlb, 350 NUMA_NO_NODE); 351 } 352 353 #endif /* CONFIG_MMU */ 354 355 void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask) 356 { 357 void *p; 358 359 if (mem_init_done) { 360 p = kzalloc(size, mask); 361 } else { 362 p = memblock_alloc(size, SMP_CACHE_BYTES); 363 if (!p) 364 panic("%s: Failed to allocate %zu bytes\n", 365 __func__, size); 366 } 367 368 return p; 369 } 370