1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/arch/parisc/mm/init.c 4 * 5 * Copyright (C) 1995 Linus Torvalds 6 * Copyright 1999 SuSE GmbH 7 * changed by Philipp Rumpf 8 * Copyright 1999 Philipp Rumpf (prumpf@tux.org) 9 * Copyright 2004 Randolph Chung (tausq@debian.org) 10 * Copyright 2006-2007 Helge Deller (deller@gmx.de) 11 * 12 */ 13 14 15 #include <linux/module.h> 16 #include <linux/mm.h> 17 #include <linux/bootmem.h> 18 #include <linux/memblock.h> 19 #include <linux/gfp.h> 20 #include <linux/delay.h> 21 #include <linux/init.h> 22 #include <linux/initrd.h> 23 #include <linux/swap.h> 24 #include <linux/unistd.h> 25 #include <linux/nodemask.h> /* for node_online_map */ 26 #include <linux/pagemap.h> /* for release_pages */ 27 #include <linux/compat.h> 28 29 #include <asm/pgalloc.h> 30 #include <asm/pgtable.h> 31 #include <asm/tlb.h> 32 #include <asm/pdc_chassis.h> 33 #include <asm/mmzone.h> 34 #include <asm/sections.h> 35 #include <asm/msgbuf.h> 36 37 extern int data_start; 38 extern void parisc_kernel_start(void); /* Kernel entry point in head.S */ 39 40 #if CONFIG_PGTABLE_LEVELS == 3 41 /* NOTE: This layout exactly conforms to the hybrid L2/L3 page table layout 42 * with the first pmd adjacent to the pgd and below it. gcc doesn't actually 43 * guarantee that global objects will be laid out in memory in the same order 44 * as the order of declaration, so put these in different sections and use 45 * the linker script to order them. */ 46 pmd_t pmd0[PTRS_PER_PMD] __attribute__ ((__section__ (".data..vm0.pmd"), aligned(PAGE_SIZE))); 47 #endif 48 49 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__ ((__section__ (".data..vm0.pgd"), aligned(PAGE_SIZE))); 50 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __attribute__ ((__section__ (".data..vm0.pte"), aligned(PAGE_SIZE))); 51 52 #ifdef CONFIG_DISCONTIGMEM 53 struct node_map_data node_data[MAX_NUMNODES] __read_mostly; 54 signed char pfnnid_map[PFNNID_MAP_MAX] __read_mostly; 55 #endif 56 57 static struct resource data_resource = { 58 .name = "Kernel data", 59 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 60 }; 61 62 static struct resource code_resource = { 63 .name = "Kernel code", 64 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 65 }; 66 67 static struct resource pdcdata_resource = { 68 .name = "PDC data (Page Zero)", 69 .start = 0, 70 .end = 0x9ff, 71 .flags = IORESOURCE_BUSY | IORESOURCE_MEM, 72 }; 73 74 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __read_mostly; 75 76 /* The following array is initialized from the firmware specific 77 * information retrieved in kernel/inventory.c. 78 */ 79 80 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __read_mostly; 81 int npmem_ranges __read_mostly; 82 83 /* 84 * get_memblock() allocates pages via memblock. 85 * We can't use memblock_find_in_range(0, KERNEL_INITIAL_SIZE) here since it 86 * doesn't allocate from bottom to top which is needed because we only created 87 * the initial mapping up to KERNEL_INITIAL_SIZE in the assembly bootup code. 88 */ 89 static void * __init get_memblock(unsigned long size) 90 { 91 static phys_addr_t search_addr __initdata; 92 phys_addr_t phys; 93 94 if (!search_addr) 95 search_addr = PAGE_ALIGN(__pa((unsigned long) &_end)); 96 search_addr = ALIGN(search_addr, size); 97 while (!memblock_is_region_memory(search_addr, size) || 98 memblock_is_region_reserved(search_addr, size)) { 99 search_addr += size; 100 } 101 phys = search_addr; 102 103 if (phys) 104 memblock_reserve(phys, size); 105 else 106 panic("get_memblock() failed.\n"); 107 108 memset(__va(phys), 0, size); 109 110 return __va(phys); 111 } 112 113 #ifdef CONFIG_64BIT 114 #define MAX_MEM (~0UL) 115 #else /* !CONFIG_64BIT */ 116 #define MAX_MEM (3584U*1024U*1024U) 117 #endif /* !CONFIG_64BIT */ 118 119 static unsigned long mem_limit __read_mostly = MAX_MEM; 120 121 static void __init mem_limit_func(void) 122 { 123 char *cp, *end; 124 unsigned long limit; 125 126 /* We need this before __setup() functions are called */ 127 128 limit = MAX_MEM; 129 for (cp = boot_command_line; *cp; ) { 130 if (memcmp(cp, "mem=", 4) == 0) { 131 cp += 4; 132 limit = memparse(cp, &end); 133 if (end != cp) 134 break; 135 cp = end; 136 } else { 137 while (*cp != ' ' && *cp) 138 ++cp; 139 while (*cp == ' ') 140 ++cp; 141 } 142 } 143 144 if (limit < mem_limit) 145 mem_limit = limit; 146 } 147 148 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT) 149 150 static void __init setup_bootmem(void) 151 { 152 unsigned long mem_max; 153 #ifndef CONFIG_DISCONTIGMEM 154 physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1]; 155 int npmem_holes; 156 #endif 157 int i, sysram_resource_count; 158 159 disable_sr_hashing(); /* Turn off space register hashing */ 160 161 /* 162 * Sort the ranges. Since the number of ranges is typically 163 * small, and performance is not an issue here, just do 164 * a simple insertion sort. 165 */ 166 167 for (i = 1; i < npmem_ranges; i++) { 168 int j; 169 170 for (j = i; j > 0; j--) { 171 unsigned long tmp; 172 173 if (pmem_ranges[j-1].start_pfn < 174 pmem_ranges[j].start_pfn) { 175 176 break; 177 } 178 tmp = pmem_ranges[j-1].start_pfn; 179 pmem_ranges[j-1].start_pfn = pmem_ranges[j].start_pfn; 180 pmem_ranges[j].start_pfn = tmp; 181 tmp = pmem_ranges[j-1].pages; 182 pmem_ranges[j-1].pages = pmem_ranges[j].pages; 183 pmem_ranges[j].pages = tmp; 184 } 185 } 186 187 #ifndef CONFIG_DISCONTIGMEM 188 /* 189 * Throw out ranges that are too far apart (controlled by 190 * MAX_GAP). 191 */ 192 193 for (i = 1; i < npmem_ranges; i++) { 194 if (pmem_ranges[i].start_pfn - 195 (pmem_ranges[i-1].start_pfn + 196 pmem_ranges[i-1].pages) > MAX_GAP) { 197 npmem_ranges = i; 198 printk("Large gap in memory detected (%ld pages). " 199 "Consider turning on CONFIG_DISCONTIGMEM\n", 200 pmem_ranges[i].start_pfn - 201 (pmem_ranges[i-1].start_pfn + 202 pmem_ranges[i-1].pages)); 203 break; 204 } 205 } 206 #endif 207 208 /* Print the memory ranges */ 209 pr_info("Memory Ranges:\n"); 210 211 for (i = 0; i < npmem_ranges; i++) { 212 struct resource *res = &sysram_resources[i]; 213 unsigned long start; 214 unsigned long size; 215 216 size = (pmem_ranges[i].pages << PAGE_SHIFT); 217 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT); 218 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n", 219 i, start, start + (size - 1), size >> 20); 220 221 /* request memory resource */ 222 res->name = "System RAM"; 223 res->start = start; 224 res->end = start + size - 1; 225 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 226 request_resource(&iomem_resource, res); 227 } 228 229 sysram_resource_count = npmem_ranges; 230 231 /* 232 * For 32 bit kernels we limit the amount of memory we can 233 * support, in order to preserve enough kernel address space 234 * for other purposes. For 64 bit kernels we don't normally 235 * limit the memory, but this mechanism can be used to 236 * artificially limit the amount of memory (and it is written 237 * to work with multiple memory ranges). 238 */ 239 240 mem_limit_func(); /* check for "mem=" argument */ 241 242 mem_max = 0; 243 for (i = 0; i < npmem_ranges; i++) { 244 unsigned long rsize; 245 246 rsize = pmem_ranges[i].pages << PAGE_SHIFT; 247 if ((mem_max + rsize) > mem_limit) { 248 printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20); 249 if (mem_max == mem_limit) 250 npmem_ranges = i; 251 else { 252 pmem_ranges[i].pages = (mem_limit >> PAGE_SHIFT) 253 - (mem_max >> PAGE_SHIFT); 254 npmem_ranges = i + 1; 255 mem_max = mem_limit; 256 } 257 break; 258 } 259 mem_max += rsize; 260 } 261 262 printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20); 263 264 #ifndef CONFIG_DISCONTIGMEM 265 /* Merge the ranges, keeping track of the holes */ 266 267 { 268 unsigned long end_pfn; 269 unsigned long hole_pages; 270 271 npmem_holes = 0; 272 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages; 273 for (i = 1; i < npmem_ranges; i++) { 274 275 hole_pages = pmem_ranges[i].start_pfn - end_pfn; 276 if (hole_pages) { 277 pmem_holes[npmem_holes].start_pfn = end_pfn; 278 pmem_holes[npmem_holes++].pages = hole_pages; 279 end_pfn += hole_pages; 280 } 281 end_pfn += pmem_ranges[i].pages; 282 } 283 284 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn; 285 npmem_ranges = 1; 286 } 287 #endif 288 289 #ifdef CONFIG_DISCONTIGMEM 290 for (i = 0; i < MAX_PHYSMEM_RANGES; i++) { 291 memset(NODE_DATA(i), 0, sizeof(pg_data_t)); 292 } 293 memset(pfnnid_map, 0xff, sizeof(pfnnid_map)); 294 295 for (i = 0; i < npmem_ranges; i++) { 296 node_set_state(i, N_NORMAL_MEMORY); 297 node_set_online(i); 298 } 299 #endif 300 301 /* 302 * Initialize and free the full range of memory in each range. 303 */ 304 305 max_pfn = 0; 306 for (i = 0; i < npmem_ranges; i++) { 307 unsigned long start_pfn; 308 unsigned long npages; 309 unsigned long start; 310 unsigned long size; 311 312 start_pfn = pmem_ranges[i].start_pfn; 313 npages = pmem_ranges[i].pages; 314 315 start = start_pfn << PAGE_SHIFT; 316 size = npages << PAGE_SHIFT; 317 318 /* add system RAM memblock */ 319 memblock_add(start, size); 320 321 if ((start_pfn + npages) > max_pfn) 322 max_pfn = start_pfn + npages; 323 } 324 325 /* IOMMU is always used to access "high mem" on those boxes 326 * that can support enough mem that a PCI device couldn't 327 * directly DMA to any physical addresses. 328 * ISA DMA support will need to revisit this. 329 */ 330 max_low_pfn = max_pfn; 331 332 /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */ 333 334 #define PDC_CONSOLE_IO_IODC_SIZE 32768 335 336 memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free + 337 PDC_CONSOLE_IO_IODC_SIZE)); 338 memblock_reserve(__pa(KERNEL_BINARY_TEXT_START), 339 (unsigned long)(_end - KERNEL_BINARY_TEXT_START)); 340 341 #ifndef CONFIG_DISCONTIGMEM 342 343 /* reserve the holes */ 344 345 for (i = 0; i < npmem_holes; i++) { 346 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT), 347 (pmem_holes[i].pages << PAGE_SHIFT)); 348 } 349 #endif 350 351 #ifdef CONFIG_BLK_DEV_INITRD 352 if (initrd_start) { 353 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end); 354 if (__pa(initrd_start) < mem_max) { 355 unsigned long initrd_reserve; 356 357 if (__pa(initrd_end) > mem_max) { 358 initrd_reserve = mem_max - __pa(initrd_start); 359 } else { 360 initrd_reserve = initrd_end - initrd_start; 361 } 362 initrd_below_start_ok = 1; 363 printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max); 364 365 memblock_reserve(__pa(initrd_start), initrd_reserve); 366 } 367 } 368 #endif 369 370 data_resource.start = virt_to_phys(&data_start); 371 data_resource.end = virt_to_phys(_end) - 1; 372 code_resource.start = virt_to_phys(_text); 373 code_resource.end = virt_to_phys(&data_start)-1; 374 375 /* We don't know which region the kernel will be in, so try 376 * all of them. 377 */ 378 for (i = 0; i < sysram_resource_count; i++) { 379 struct resource *res = &sysram_resources[i]; 380 request_resource(res, &code_resource); 381 request_resource(res, &data_resource); 382 } 383 request_resource(&sysram_resources[0], &pdcdata_resource); 384 385 /* Initialize Page Deallocation Table (PDT) and check for bad memory. */ 386 pdc_pdt_init(); 387 } 388 389 static int __init parisc_text_address(unsigned long vaddr) 390 { 391 static unsigned long head_ptr __initdata; 392 393 if (!head_ptr) 394 head_ptr = PAGE_MASK & (unsigned long) 395 dereference_function_descriptor(&parisc_kernel_start); 396 397 return core_kernel_text(vaddr) || vaddr == head_ptr; 398 } 399 400 static void __init map_pages(unsigned long start_vaddr, 401 unsigned long start_paddr, unsigned long size, 402 pgprot_t pgprot, int force) 403 { 404 pgd_t *pg_dir; 405 pmd_t *pmd; 406 pte_t *pg_table; 407 unsigned long end_paddr; 408 unsigned long start_pmd; 409 unsigned long start_pte; 410 unsigned long tmp1; 411 unsigned long tmp2; 412 unsigned long address; 413 unsigned long vaddr; 414 unsigned long ro_start; 415 unsigned long ro_end; 416 unsigned long kernel_end; 417 418 ro_start = __pa((unsigned long)_text); 419 ro_end = __pa((unsigned long)&data_start); 420 kernel_end = __pa((unsigned long)&_end); 421 422 end_paddr = start_paddr + size; 423 424 pg_dir = pgd_offset_k(start_vaddr); 425 426 #if PTRS_PER_PMD == 1 427 start_pmd = 0; 428 #else 429 start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1)); 430 #endif 431 start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)); 432 433 address = start_paddr; 434 vaddr = start_vaddr; 435 while (address < end_paddr) { 436 #if PTRS_PER_PMD == 1 437 pmd = (pmd_t *)__pa(pg_dir); 438 #else 439 pmd = (pmd_t *)pgd_address(*pg_dir); 440 441 /* 442 * pmd is physical at this point 443 */ 444 445 if (!pmd) { 446 pmd = (pmd_t *) get_memblock(PAGE_SIZE << PMD_ORDER); 447 pmd = (pmd_t *) __pa(pmd); 448 } 449 450 pgd_populate(NULL, pg_dir, __va(pmd)); 451 #endif 452 pg_dir++; 453 454 /* now change pmd to kernel virtual addresses */ 455 456 pmd = (pmd_t *)__va(pmd) + start_pmd; 457 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) { 458 459 /* 460 * pg_table is physical at this point 461 */ 462 463 pg_table = (pte_t *)pmd_address(*pmd); 464 if (!pg_table) { 465 pg_table = (pte_t *) get_memblock(PAGE_SIZE); 466 pg_table = (pte_t *) __pa(pg_table); 467 } 468 469 pmd_populate_kernel(NULL, pmd, __va(pg_table)); 470 471 /* now change pg_table to kernel virtual addresses */ 472 473 pg_table = (pte_t *) __va(pg_table) + start_pte; 474 for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) { 475 pte_t pte; 476 477 if (force) 478 pte = __mk_pte(address, pgprot); 479 else if (parisc_text_address(vaddr)) { 480 pte = __mk_pte(address, PAGE_KERNEL_EXEC); 481 if (address >= ro_start && address < kernel_end) 482 pte = pte_mkhuge(pte); 483 } 484 else 485 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB) 486 if (address >= ro_start && address < ro_end) { 487 pte = __mk_pte(address, PAGE_KERNEL_EXEC); 488 pte = pte_mkhuge(pte); 489 } else 490 #endif 491 { 492 pte = __mk_pte(address, pgprot); 493 if (address >= ro_start && address < kernel_end) 494 pte = pte_mkhuge(pte); 495 } 496 497 if (address >= end_paddr) { 498 if (force) 499 break; 500 else 501 pte_val(pte) = 0; 502 } 503 504 set_pte(pg_table, pte); 505 506 address += PAGE_SIZE; 507 vaddr += PAGE_SIZE; 508 } 509 start_pte = 0; 510 511 if (address >= end_paddr) 512 break; 513 } 514 start_pmd = 0; 515 } 516 } 517 518 void __ref free_initmem(void) 519 { 520 unsigned long init_begin = (unsigned long)__init_begin; 521 unsigned long init_end = (unsigned long)__init_end; 522 523 /* The init text pages are marked R-X. We have to 524 * flush the icache and mark them RW- 525 * 526 * This is tricky, because map_pages is in the init section. 527 * Do a dummy remap of the data section first (the data 528 * section is already PAGE_KERNEL) to pull in the TLB entries 529 * for map_kernel */ 530 map_pages(init_begin, __pa(init_begin), init_end - init_begin, 531 PAGE_KERNEL_RWX, 1); 532 /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute 533 * map_pages */ 534 map_pages(init_begin, __pa(init_begin), init_end - init_begin, 535 PAGE_KERNEL, 1); 536 537 /* force the kernel to see the new TLB entries */ 538 __flush_tlb_range(0, init_begin, init_end); 539 540 /* finally dump all the instructions which were cached, since the 541 * pages are no-longer executable */ 542 flush_icache_range(init_begin, init_end); 543 544 free_initmem_default(POISON_FREE_INITMEM); 545 546 /* set up a new led state on systems shipped LED State panel */ 547 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE); 548 } 549 550 551 #ifdef CONFIG_STRICT_KERNEL_RWX 552 void mark_rodata_ro(void) 553 { 554 /* rodata memory was already mapped with KERNEL_RO access rights by 555 pagetable_init() and map_pages(). No need to do additional stuff here */ 556 printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n", 557 (unsigned long)(__end_rodata - __start_rodata) >> 10); 558 } 559 #endif 560 561 562 /* 563 * Just an arbitrary offset to serve as a "hole" between mapping areas 564 * (between top of physical memory and a potential pcxl dma mapping 565 * area, and below the vmalloc mapping area). 566 * 567 * The current 32K value just means that there will be a 32K "hole" 568 * between mapping areas. That means that any out-of-bounds memory 569 * accesses will hopefully be caught. The vmalloc() routines leaves 570 * a hole of 4kB between each vmalloced area for the same reason. 571 */ 572 573 /* Leave room for gateway page expansion */ 574 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE 575 #error KERNEL_MAP_START is in gateway reserved region 576 #endif 577 #define MAP_START (KERNEL_MAP_START) 578 579 #define VM_MAP_OFFSET (32*1024) 580 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \ 581 & ~(VM_MAP_OFFSET-1))) 582 583 void *parisc_vmalloc_start __read_mostly; 584 EXPORT_SYMBOL(parisc_vmalloc_start); 585 586 #ifdef CONFIG_PA11 587 unsigned long pcxl_dma_start __read_mostly; 588 #endif 589 590 void __init mem_init(void) 591 { 592 /* Do sanity checks on IPC (compat) structures */ 593 BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48); 594 #ifndef CONFIG_64BIT 595 BUILD_BUG_ON(sizeof(struct semid64_ds) != 80); 596 BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104); 597 BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104); 598 #endif 599 #ifdef CONFIG_COMPAT 600 BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm)); 601 BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80); 602 BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104); 603 BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104); 604 #endif 605 606 /* Do sanity checks on page table constants */ 607 BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t)); 608 BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t)); 609 BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t)); 610 BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD 611 > BITS_PER_LONG); 612 613 high_memory = __va((max_pfn << PAGE_SHIFT)); 614 set_max_mapnr(page_to_pfn(virt_to_page(high_memory - 1)) + 1); 615 free_all_bootmem(); 616 617 #ifdef CONFIG_PA11 618 if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) { 619 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START); 620 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start 621 + PCXL_DMA_MAP_SIZE); 622 } else 623 #endif 624 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START); 625 626 mem_init_print_info(NULL); 627 628 #if 0 629 /* 630 * Do not expose the virtual kernel memory layout to userspace. 631 * But keep code for debugging purposes. 632 */ 633 printk("virtual kernel memory layout:\n" 634 " vmalloc : 0x%px - 0x%px (%4ld MB)\n" 635 " memory : 0x%px - 0x%px (%4ld MB)\n" 636 " .init : 0x%px - 0x%px (%4ld kB)\n" 637 " .data : 0x%px - 0x%px (%4ld kB)\n" 638 " .text : 0x%px - 0x%px (%4ld kB)\n", 639 640 (void*)VMALLOC_START, (void*)VMALLOC_END, 641 (VMALLOC_END - VMALLOC_START) >> 20, 642 643 __va(0), high_memory, 644 ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20, 645 646 __init_begin, __init_end, 647 ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10, 648 649 _etext, _edata, 650 ((unsigned long)_edata - (unsigned long)_etext) >> 10, 651 652 _text, _etext, 653 ((unsigned long)_etext - (unsigned long)_text) >> 10); 654 #endif 655 } 656 657 unsigned long *empty_zero_page __read_mostly; 658 EXPORT_SYMBOL(empty_zero_page); 659 660 /* 661 * pagetable_init() sets up the page tables 662 * 663 * Note that gateway_init() places the Linux gateway page at page 0. 664 * Since gateway pages cannot be dereferenced this has the desirable 665 * side effect of trapping those pesky NULL-reference errors in the 666 * kernel. 667 */ 668 static void __init pagetable_init(void) 669 { 670 int range; 671 672 /* Map each physical memory range to its kernel vaddr */ 673 674 for (range = 0; range < npmem_ranges; range++) { 675 unsigned long start_paddr; 676 unsigned long end_paddr; 677 unsigned long size; 678 679 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT; 680 size = pmem_ranges[range].pages << PAGE_SHIFT; 681 end_paddr = start_paddr + size; 682 683 map_pages((unsigned long)__va(start_paddr), start_paddr, 684 size, PAGE_KERNEL, 0); 685 } 686 687 #ifdef CONFIG_BLK_DEV_INITRD 688 if (initrd_end && initrd_end > mem_limit) { 689 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end); 690 map_pages(initrd_start, __pa(initrd_start), 691 initrd_end - initrd_start, PAGE_KERNEL, 0); 692 } 693 #endif 694 695 empty_zero_page = get_memblock(PAGE_SIZE); 696 } 697 698 static void __init gateway_init(void) 699 { 700 unsigned long linux_gateway_page_addr; 701 /* FIXME: This is 'const' in order to trick the compiler 702 into not treating it as DP-relative data. */ 703 extern void * const linux_gateway_page; 704 705 linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK; 706 707 /* 708 * Setup Linux Gateway page. 709 * 710 * The Linux gateway page will reside in kernel space (on virtual 711 * page 0), so it doesn't need to be aliased into user space. 712 */ 713 714 map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page), 715 PAGE_SIZE, PAGE_GATEWAY, 1); 716 } 717 718 void __init paging_init(void) 719 { 720 int i; 721 722 setup_bootmem(); 723 pagetable_init(); 724 gateway_init(); 725 flush_cache_all_local(); /* start with known state */ 726 flush_tlb_all_local(NULL); 727 728 for (i = 0; i < npmem_ranges; i++) { 729 unsigned long zones_size[MAX_NR_ZONES] = { 0, }; 730 731 zones_size[ZONE_NORMAL] = pmem_ranges[i].pages; 732 733 #ifdef CONFIG_DISCONTIGMEM 734 /* Need to initialize the pfnnid_map before we can initialize 735 the zone */ 736 { 737 int j; 738 for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT); 739 j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT); 740 j++) { 741 pfnnid_map[j] = i; 742 } 743 } 744 #endif 745 746 free_area_init_node(i, zones_size, 747 pmem_ranges[i].start_pfn, NULL); 748 } 749 } 750 751 #ifdef CONFIG_PA20 752 753 /* 754 * Currently, all PA20 chips have 18 bit protection IDs, which is the 755 * limiting factor (space ids are 32 bits). 756 */ 757 758 #define NR_SPACE_IDS 262144 759 760 #else 761 762 /* 763 * Currently we have a one-to-one relationship between space IDs and 764 * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only 765 * support 15 bit protection IDs, so that is the limiting factor. 766 * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's 767 * probably not worth the effort for a special case here. 768 */ 769 770 #define NR_SPACE_IDS 32768 771 772 #endif /* !CONFIG_PA20 */ 773 774 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2) 775 #define SID_ARRAY_SIZE (NR_SPACE_IDS / (8 * sizeof(long))) 776 777 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */ 778 static unsigned long dirty_space_id[SID_ARRAY_SIZE]; 779 static unsigned long space_id_index; 780 static unsigned long free_space_ids = NR_SPACE_IDS - 1; 781 static unsigned long dirty_space_ids = 0; 782 783 static DEFINE_SPINLOCK(sid_lock); 784 785 unsigned long alloc_sid(void) 786 { 787 unsigned long index; 788 789 spin_lock(&sid_lock); 790 791 if (free_space_ids == 0) { 792 if (dirty_space_ids != 0) { 793 spin_unlock(&sid_lock); 794 flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */ 795 spin_lock(&sid_lock); 796 } 797 BUG_ON(free_space_ids == 0); 798 } 799 800 free_space_ids--; 801 802 index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index); 803 space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1))); 804 space_id_index = index; 805 806 spin_unlock(&sid_lock); 807 808 return index << SPACEID_SHIFT; 809 } 810 811 void free_sid(unsigned long spaceid) 812 { 813 unsigned long index = spaceid >> SPACEID_SHIFT; 814 unsigned long *dirty_space_offset; 815 816 dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG); 817 index &= (BITS_PER_LONG - 1); 818 819 spin_lock(&sid_lock); 820 821 BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */ 822 823 *dirty_space_offset |= (1L << index); 824 dirty_space_ids++; 825 826 spin_unlock(&sid_lock); 827 } 828 829 830 #ifdef CONFIG_SMP 831 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array) 832 { 833 int i; 834 835 /* NOTE: sid_lock must be held upon entry */ 836 837 *ndirtyptr = dirty_space_ids; 838 if (dirty_space_ids != 0) { 839 for (i = 0; i < SID_ARRAY_SIZE; i++) { 840 dirty_array[i] = dirty_space_id[i]; 841 dirty_space_id[i] = 0; 842 } 843 dirty_space_ids = 0; 844 } 845 846 return; 847 } 848 849 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array) 850 { 851 int i; 852 853 /* NOTE: sid_lock must be held upon entry */ 854 855 if (ndirty != 0) { 856 for (i = 0; i < SID_ARRAY_SIZE; i++) { 857 space_id[i] ^= dirty_array[i]; 858 } 859 860 free_space_ids += ndirty; 861 space_id_index = 0; 862 } 863 } 864 865 #else /* CONFIG_SMP */ 866 867 static void recycle_sids(void) 868 { 869 int i; 870 871 /* NOTE: sid_lock must be held upon entry */ 872 873 if (dirty_space_ids != 0) { 874 for (i = 0; i < SID_ARRAY_SIZE; i++) { 875 space_id[i] ^= dirty_space_id[i]; 876 dirty_space_id[i] = 0; 877 } 878 879 free_space_ids += dirty_space_ids; 880 dirty_space_ids = 0; 881 space_id_index = 0; 882 } 883 } 884 #endif 885 886 /* 887 * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is 888 * purged, we can safely reuse the space ids that were released but 889 * not flushed from the tlb. 890 */ 891 892 #ifdef CONFIG_SMP 893 894 static unsigned long recycle_ndirty; 895 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE]; 896 static unsigned int recycle_inuse; 897 898 void flush_tlb_all(void) 899 { 900 int do_recycle; 901 902 __inc_irq_stat(irq_tlb_count); 903 do_recycle = 0; 904 spin_lock(&sid_lock); 905 if (dirty_space_ids > RECYCLE_THRESHOLD) { 906 BUG_ON(recycle_inuse); /* FIXME: Use a semaphore/wait queue here */ 907 get_dirty_sids(&recycle_ndirty,recycle_dirty_array); 908 recycle_inuse++; 909 do_recycle++; 910 } 911 spin_unlock(&sid_lock); 912 on_each_cpu(flush_tlb_all_local, NULL, 1); 913 if (do_recycle) { 914 spin_lock(&sid_lock); 915 recycle_sids(recycle_ndirty,recycle_dirty_array); 916 recycle_inuse = 0; 917 spin_unlock(&sid_lock); 918 } 919 } 920 #else 921 void flush_tlb_all(void) 922 { 923 __inc_irq_stat(irq_tlb_count); 924 spin_lock(&sid_lock); 925 flush_tlb_all_local(NULL); 926 recycle_sids(); 927 spin_unlock(&sid_lock); 928 } 929 #endif 930 931 #ifdef CONFIG_BLK_DEV_INITRD 932 void free_initrd_mem(unsigned long start, unsigned long end) 933 { 934 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 935 } 936 #endif 937