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