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 #include <asm/sparsemem.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 static struct resource data_resource = { 53 .name = "Kernel data", 54 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 55 }; 56 57 static struct resource code_resource = { 58 .name = "Kernel code", 59 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 60 }; 61 62 static struct resource pdcdata_resource = { 63 .name = "PDC data (Page Zero)", 64 .start = 0, 65 .end = 0x9ff, 66 .flags = IORESOURCE_BUSY | IORESOURCE_MEM, 67 }; 68 69 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init; 70 71 /* The following array is initialized from the firmware specific 72 * information retrieved in kernel/inventory.c. 73 */ 74 75 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata; 76 int npmem_ranges __initdata; 77 78 #ifdef CONFIG_64BIT 79 #define MAX_MEM (1UL << MAX_PHYSMEM_BITS) 80 #else /* !CONFIG_64BIT */ 81 #define MAX_MEM (3584U*1024U*1024U) 82 #endif /* !CONFIG_64BIT */ 83 84 static unsigned long mem_limit __read_mostly = MAX_MEM; 85 86 static void __init mem_limit_func(void) 87 { 88 char *cp, *end; 89 unsigned long limit; 90 91 /* We need this before __setup() functions are called */ 92 93 limit = MAX_MEM; 94 for (cp = boot_command_line; *cp; ) { 95 if (memcmp(cp, "mem=", 4) == 0) { 96 cp += 4; 97 limit = memparse(cp, &end); 98 if (end != cp) 99 break; 100 cp = end; 101 } else { 102 while (*cp != ' ' && *cp) 103 ++cp; 104 while (*cp == ' ') 105 ++cp; 106 } 107 } 108 109 if (limit < mem_limit) 110 mem_limit = limit; 111 } 112 113 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT) 114 115 static void __init setup_bootmem(void) 116 { 117 unsigned long mem_max; 118 #ifndef CONFIG_SPARSEMEM 119 physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1]; 120 int npmem_holes; 121 #endif 122 int i, sysram_resource_count; 123 124 disable_sr_hashing(); /* Turn off space register hashing */ 125 126 /* 127 * Sort the ranges. Since the number of ranges is typically 128 * small, and performance is not an issue here, just do 129 * a simple insertion sort. 130 */ 131 132 for (i = 1; i < npmem_ranges; i++) { 133 int j; 134 135 for (j = i; j > 0; j--) { 136 physmem_range_t tmp; 137 138 if (pmem_ranges[j-1].start_pfn < 139 pmem_ranges[j].start_pfn) { 140 141 break; 142 } 143 tmp = pmem_ranges[j-1]; 144 pmem_ranges[j-1] = pmem_ranges[j]; 145 pmem_ranges[j] = tmp; 146 } 147 } 148 149 #ifndef CONFIG_SPARSEMEM 150 /* 151 * Throw out ranges that are too far apart (controlled by 152 * MAX_GAP). 153 */ 154 155 for (i = 1; i < npmem_ranges; i++) { 156 if (pmem_ranges[i].start_pfn - 157 (pmem_ranges[i-1].start_pfn + 158 pmem_ranges[i-1].pages) > MAX_GAP) { 159 npmem_ranges = i; 160 printk("Large gap in memory detected (%ld pages). " 161 "Consider turning on CONFIG_SPARSEMEM\n", 162 pmem_ranges[i].start_pfn - 163 (pmem_ranges[i-1].start_pfn + 164 pmem_ranges[i-1].pages)); 165 break; 166 } 167 } 168 #endif 169 170 /* Print the memory ranges */ 171 pr_info("Memory Ranges:\n"); 172 173 for (i = 0; i < npmem_ranges; i++) { 174 struct resource *res = &sysram_resources[i]; 175 unsigned long start; 176 unsigned long size; 177 178 size = (pmem_ranges[i].pages << PAGE_SHIFT); 179 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT); 180 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n", 181 i, start, start + (size - 1), size >> 20); 182 183 /* request memory resource */ 184 res->name = "System RAM"; 185 res->start = start; 186 res->end = start + size - 1; 187 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 188 request_resource(&iomem_resource, res); 189 } 190 191 sysram_resource_count = npmem_ranges; 192 193 /* 194 * For 32 bit kernels we limit the amount of memory we can 195 * support, in order to preserve enough kernel address space 196 * for other purposes. For 64 bit kernels we don't normally 197 * limit the memory, but this mechanism can be used to 198 * artificially limit the amount of memory (and it is written 199 * to work with multiple memory ranges). 200 */ 201 202 mem_limit_func(); /* check for "mem=" argument */ 203 204 mem_max = 0; 205 for (i = 0; i < npmem_ranges; i++) { 206 unsigned long rsize; 207 208 rsize = pmem_ranges[i].pages << PAGE_SHIFT; 209 if ((mem_max + rsize) > mem_limit) { 210 printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20); 211 if (mem_max == mem_limit) 212 npmem_ranges = i; 213 else { 214 pmem_ranges[i].pages = (mem_limit >> PAGE_SHIFT) 215 - (mem_max >> PAGE_SHIFT); 216 npmem_ranges = i + 1; 217 mem_max = mem_limit; 218 } 219 break; 220 } 221 mem_max += rsize; 222 } 223 224 printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20); 225 226 #ifndef CONFIG_SPARSEMEM 227 /* Merge the ranges, keeping track of the holes */ 228 { 229 unsigned long end_pfn; 230 unsigned long hole_pages; 231 232 npmem_holes = 0; 233 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages; 234 for (i = 1; i < npmem_ranges; i++) { 235 236 hole_pages = pmem_ranges[i].start_pfn - end_pfn; 237 if (hole_pages) { 238 pmem_holes[npmem_holes].start_pfn = end_pfn; 239 pmem_holes[npmem_holes++].pages = hole_pages; 240 end_pfn += hole_pages; 241 } 242 end_pfn += pmem_ranges[i].pages; 243 } 244 245 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn; 246 npmem_ranges = 1; 247 } 248 #endif 249 250 /* 251 * Initialize and free the full range of memory in each range. 252 */ 253 254 max_pfn = 0; 255 for (i = 0; i < npmem_ranges; i++) { 256 unsigned long start_pfn; 257 unsigned long npages; 258 unsigned long start; 259 unsigned long size; 260 261 start_pfn = pmem_ranges[i].start_pfn; 262 npages = pmem_ranges[i].pages; 263 264 start = start_pfn << PAGE_SHIFT; 265 size = npages << PAGE_SHIFT; 266 267 /* add system RAM memblock */ 268 memblock_add(start, size); 269 270 if ((start_pfn + npages) > max_pfn) 271 max_pfn = start_pfn + npages; 272 } 273 274 /* 275 * We can't use memblock top-down allocations because we only 276 * created the initial mapping up to KERNEL_INITIAL_SIZE in 277 * the assembly bootup code. 278 */ 279 memblock_set_bottom_up(true); 280 281 /* IOMMU is always used to access "high mem" on those boxes 282 * that can support enough mem that a PCI device couldn't 283 * directly DMA to any physical addresses. 284 * ISA DMA support will need to revisit this. 285 */ 286 max_low_pfn = max_pfn; 287 288 /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */ 289 290 #define PDC_CONSOLE_IO_IODC_SIZE 32768 291 292 memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free + 293 PDC_CONSOLE_IO_IODC_SIZE)); 294 memblock_reserve(__pa(KERNEL_BINARY_TEXT_START), 295 (unsigned long)(_end - KERNEL_BINARY_TEXT_START)); 296 297 #ifndef CONFIG_SPARSEMEM 298 299 /* reserve the holes */ 300 301 for (i = 0; i < npmem_holes; i++) { 302 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT), 303 (pmem_holes[i].pages << PAGE_SHIFT)); 304 } 305 #endif 306 307 #ifdef CONFIG_BLK_DEV_INITRD 308 if (initrd_start) { 309 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end); 310 if (__pa(initrd_start) < mem_max) { 311 unsigned long initrd_reserve; 312 313 if (__pa(initrd_end) > mem_max) { 314 initrd_reserve = mem_max - __pa(initrd_start); 315 } else { 316 initrd_reserve = initrd_end - initrd_start; 317 } 318 initrd_below_start_ok = 1; 319 printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max); 320 321 memblock_reserve(__pa(initrd_start), initrd_reserve); 322 } 323 } 324 #endif 325 326 data_resource.start = virt_to_phys(&data_start); 327 data_resource.end = virt_to_phys(_end) - 1; 328 code_resource.start = virt_to_phys(_text); 329 code_resource.end = virt_to_phys(&data_start)-1; 330 331 /* We don't know which region the kernel will be in, so try 332 * all of them. 333 */ 334 for (i = 0; i < sysram_resource_count; i++) { 335 struct resource *res = &sysram_resources[i]; 336 request_resource(res, &code_resource); 337 request_resource(res, &data_resource); 338 } 339 request_resource(&sysram_resources[0], &pdcdata_resource); 340 341 /* Initialize Page Deallocation Table (PDT) and check for bad memory. */ 342 pdc_pdt_init(); 343 344 memblock_allow_resize(); 345 memblock_dump_all(); 346 } 347 348 static bool kernel_set_to_readonly; 349 350 static void __init map_pages(unsigned long start_vaddr, 351 unsigned long start_paddr, unsigned long size, 352 pgprot_t pgprot, int force) 353 { 354 pmd_t *pmd; 355 pte_t *pg_table; 356 unsigned long end_paddr; 357 unsigned long start_pmd; 358 unsigned long start_pte; 359 unsigned long tmp1; 360 unsigned long tmp2; 361 unsigned long address; 362 unsigned long vaddr; 363 unsigned long ro_start; 364 unsigned long ro_end; 365 unsigned long kernel_start, kernel_end; 366 367 ro_start = __pa((unsigned long)_text); 368 ro_end = __pa((unsigned long)&data_start); 369 kernel_start = __pa((unsigned long)&__init_begin); 370 kernel_end = __pa((unsigned long)&_end); 371 372 end_paddr = start_paddr + size; 373 374 /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */ 375 start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1)); 376 start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)); 377 378 address = start_paddr; 379 vaddr = start_vaddr; 380 while (address < end_paddr) { 381 pgd_t *pgd = pgd_offset_k(vaddr); 382 p4d_t *p4d = p4d_offset(pgd, vaddr); 383 pud_t *pud = pud_offset(p4d, vaddr); 384 385 #if CONFIG_PGTABLE_LEVELS == 3 386 if (pud_none(*pud)) { 387 pmd = memblock_alloc(PAGE_SIZE << PMD_ORDER, 388 PAGE_SIZE << PMD_ORDER); 389 if (!pmd) 390 panic("pmd allocation failed.\n"); 391 pud_populate(NULL, pud, pmd); 392 } 393 #endif 394 395 pmd = pmd_offset(pud, vaddr); 396 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) { 397 if (pmd_none(*pmd)) { 398 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE); 399 if (!pg_table) 400 panic("page table allocation failed\n"); 401 pmd_populate_kernel(NULL, pmd, pg_table); 402 } 403 404 pg_table = pte_offset_kernel(pmd, vaddr); 405 for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) { 406 pte_t pte; 407 pgprot_t prot; 408 bool huge = false; 409 410 if (force) { 411 prot = pgprot; 412 } else if (address < kernel_start || address >= kernel_end) { 413 /* outside kernel memory */ 414 prot = PAGE_KERNEL; 415 } else if (!kernel_set_to_readonly) { 416 /* still initializing, allow writing to RO memory */ 417 prot = PAGE_KERNEL_RWX; 418 huge = true; 419 } else if (address >= ro_start) { 420 /* Code (ro) and Data areas */ 421 prot = (address < ro_end) ? 422 PAGE_KERNEL_EXEC : PAGE_KERNEL; 423 huge = true; 424 } else { 425 prot = PAGE_KERNEL; 426 } 427 428 pte = __mk_pte(address, prot); 429 if (huge) 430 pte = pte_mkhuge(pte); 431 432 if (address >= end_paddr) 433 break; 434 435 set_pte(pg_table, pte); 436 437 address += PAGE_SIZE; 438 vaddr += PAGE_SIZE; 439 } 440 start_pte = 0; 441 442 if (address >= end_paddr) 443 break; 444 } 445 start_pmd = 0; 446 } 447 } 448 449 void __init set_kernel_text_rw(int enable_read_write) 450 { 451 unsigned long start = (unsigned long) __init_begin; 452 unsigned long end = (unsigned long) &data_start; 453 454 map_pages(start, __pa(start), end-start, 455 PAGE_KERNEL_RWX, enable_read_write ? 1:0); 456 457 /* force the kernel to see the new page table entries */ 458 flush_cache_all(); 459 flush_tlb_all(); 460 } 461 462 void __ref free_initmem(void) 463 { 464 unsigned long init_begin = (unsigned long)__init_begin; 465 unsigned long init_end = (unsigned long)__init_end; 466 unsigned long kernel_end = (unsigned long)&_end; 467 468 /* Remap kernel text and data, but do not touch init section yet. */ 469 kernel_set_to_readonly = true; 470 map_pages(init_end, __pa(init_end), kernel_end - init_end, 471 PAGE_KERNEL, 0); 472 473 /* The init text pages are marked R-X. We have to 474 * flush the icache and mark them RW- 475 * 476 * This is tricky, because map_pages is in the init section. 477 * Do a dummy remap of the data section first (the data 478 * section is already PAGE_KERNEL) to pull in the TLB entries 479 * for map_kernel */ 480 map_pages(init_begin, __pa(init_begin), init_end - init_begin, 481 PAGE_KERNEL_RWX, 1); 482 /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute 483 * map_pages */ 484 map_pages(init_begin, __pa(init_begin), init_end - init_begin, 485 PAGE_KERNEL, 1); 486 487 /* force the kernel to see the new TLB entries */ 488 __flush_tlb_range(0, init_begin, kernel_end); 489 490 /* finally dump all the instructions which were cached, since the 491 * pages are no-longer executable */ 492 flush_icache_range(init_begin, init_end); 493 494 free_initmem_default(POISON_FREE_INITMEM); 495 496 /* set up a new led state on systems shipped LED State panel */ 497 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE); 498 } 499 500 501 #ifdef CONFIG_STRICT_KERNEL_RWX 502 void mark_rodata_ro(void) 503 { 504 /* rodata memory was already mapped with KERNEL_RO access rights by 505 pagetable_init() and map_pages(). No need to do additional stuff here */ 506 unsigned long roai_size = __end_ro_after_init - __start_ro_after_init; 507 508 pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10); 509 } 510 #endif 511 512 513 /* 514 * Just an arbitrary offset to serve as a "hole" between mapping areas 515 * (between top of physical memory and a potential pcxl dma mapping 516 * area, and below the vmalloc mapping area). 517 * 518 * The current 32K value just means that there will be a 32K "hole" 519 * between mapping areas. That means that any out-of-bounds memory 520 * accesses will hopefully be caught. The vmalloc() routines leaves 521 * a hole of 4kB between each vmalloced area for the same reason. 522 */ 523 524 /* Leave room for gateway page expansion */ 525 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE 526 #error KERNEL_MAP_START is in gateway reserved region 527 #endif 528 #define MAP_START (KERNEL_MAP_START) 529 530 #define VM_MAP_OFFSET (32*1024) 531 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \ 532 & ~(VM_MAP_OFFSET-1))) 533 534 void *parisc_vmalloc_start __ro_after_init; 535 EXPORT_SYMBOL(parisc_vmalloc_start); 536 537 #ifdef CONFIG_PA11 538 unsigned long pcxl_dma_start __ro_after_init; 539 #endif 540 541 void __init mem_init(void) 542 { 543 /* Do sanity checks on IPC (compat) structures */ 544 BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48); 545 #ifndef CONFIG_64BIT 546 BUILD_BUG_ON(sizeof(struct semid64_ds) != 80); 547 BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104); 548 BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104); 549 #endif 550 #ifdef CONFIG_COMPAT 551 BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm)); 552 BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80); 553 BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104); 554 BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104); 555 #endif 556 557 /* Do sanity checks on page table constants */ 558 BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t)); 559 BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t)); 560 BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t)); 561 BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD 562 > BITS_PER_LONG); 563 564 high_memory = __va((max_pfn << PAGE_SHIFT)); 565 set_max_mapnr(max_low_pfn); 566 memblock_free_all(); 567 568 #ifdef CONFIG_PA11 569 if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) { 570 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START); 571 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start 572 + PCXL_DMA_MAP_SIZE); 573 } else 574 #endif 575 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START); 576 577 mem_init_print_info(NULL); 578 579 #if 0 580 /* 581 * Do not expose the virtual kernel memory layout to userspace. 582 * But keep code for debugging purposes. 583 */ 584 printk("virtual kernel memory layout:\n" 585 " vmalloc : 0x%px - 0x%px (%4ld MB)\n" 586 " fixmap : 0x%px - 0x%px (%4ld kB)\n" 587 " memory : 0x%px - 0x%px (%4ld MB)\n" 588 " .init : 0x%px - 0x%px (%4ld kB)\n" 589 " .data : 0x%px - 0x%px (%4ld kB)\n" 590 " .text : 0x%px - 0x%px (%4ld kB)\n", 591 592 (void*)VMALLOC_START, (void*)VMALLOC_END, 593 (VMALLOC_END - VMALLOC_START) >> 20, 594 595 (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE), 596 (unsigned long)(FIXMAP_SIZE / 1024), 597 598 __va(0), high_memory, 599 ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20, 600 601 __init_begin, __init_end, 602 ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10, 603 604 _etext, _edata, 605 ((unsigned long)_edata - (unsigned long)_etext) >> 10, 606 607 _text, _etext, 608 ((unsigned long)_etext - (unsigned long)_text) >> 10); 609 #endif 610 } 611 612 unsigned long *empty_zero_page __ro_after_init; 613 EXPORT_SYMBOL(empty_zero_page); 614 615 /* 616 * pagetable_init() sets up the page tables 617 * 618 * Note that gateway_init() places the Linux gateway page at page 0. 619 * Since gateway pages cannot be dereferenced this has the desirable 620 * side effect of trapping those pesky NULL-reference errors in the 621 * kernel. 622 */ 623 static void __init pagetable_init(void) 624 { 625 int range; 626 627 /* Map each physical memory range to its kernel vaddr */ 628 629 for (range = 0; range < npmem_ranges; range++) { 630 unsigned long start_paddr; 631 unsigned long end_paddr; 632 unsigned long size; 633 634 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT; 635 size = pmem_ranges[range].pages << PAGE_SHIFT; 636 end_paddr = start_paddr + size; 637 638 map_pages((unsigned long)__va(start_paddr), start_paddr, 639 size, PAGE_KERNEL, 0); 640 } 641 642 #ifdef CONFIG_BLK_DEV_INITRD 643 if (initrd_end && initrd_end > mem_limit) { 644 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end); 645 map_pages(initrd_start, __pa(initrd_start), 646 initrd_end - initrd_start, PAGE_KERNEL, 0); 647 } 648 #endif 649 650 empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE); 651 if (!empty_zero_page) 652 panic("zero page allocation failed.\n"); 653 654 } 655 656 static void __init gateway_init(void) 657 { 658 unsigned long linux_gateway_page_addr; 659 /* FIXME: This is 'const' in order to trick the compiler 660 into not treating it as DP-relative data. */ 661 extern void * const linux_gateway_page; 662 663 linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK; 664 665 /* 666 * Setup Linux Gateway page. 667 * 668 * The Linux gateway page will reside in kernel space (on virtual 669 * page 0), so it doesn't need to be aliased into user space. 670 */ 671 672 map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page), 673 PAGE_SIZE, PAGE_GATEWAY, 1); 674 } 675 676 static void __init parisc_bootmem_free(void) 677 { 678 unsigned long zones_size[MAX_NR_ZONES] = { 0, }; 679 unsigned long holes_size[MAX_NR_ZONES] = { 0, }; 680 unsigned long mem_start_pfn = ~0UL, mem_end_pfn = 0, mem_size_pfn = 0; 681 int i; 682 683 for (i = 0; i < npmem_ranges; i++) { 684 unsigned long start = pmem_ranges[i].start_pfn; 685 unsigned long size = pmem_ranges[i].pages; 686 unsigned long end = start + size; 687 688 if (mem_start_pfn > start) 689 mem_start_pfn = start; 690 if (mem_end_pfn < end) 691 mem_end_pfn = end; 692 mem_size_pfn += size; 693 } 694 695 zones_size[0] = mem_end_pfn - mem_start_pfn; 696 holes_size[0] = zones_size[0] - mem_size_pfn; 697 698 free_area_init_node(0, zones_size, mem_start_pfn, holes_size); 699 } 700 701 void __init paging_init(void) 702 { 703 setup_bootmem(); 704 pagetable_init(); 705 gateway_init(); 706 flush_cache_all_local(); /* start with known state */ 707 flush_tlb_all_local(NULL); 708 709 /* 710 * Mark all memblocks as present for sparsemem using 711 * memory_present() and then initialize sparsemem. 712 */ 713 memblocks_present(); 714 sparse_init(); 715 parisc_bootmem_free(); 716 } 717 718 #ifdef CONFIG_PA20 719 720 /* 721 * Currently, all PA20 chips have 18 bit protection IDs, which is the 722 * limiting factor (space ids are 32 bits). 723 */ 724 725 #define NR_SPACE_IDS 262144 726 727 #else 728 729 /* 730 * Currently we have a one-to-one relationship between space IDs and 731 * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only 732 * support 15 bit protection IDs, so that is the limiting factor. 733 * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's 734 * probably not worth the effort for a special case here. 735 */ 736 737 #define NR_SPACE_IDS 32768 738 739 #endif /* !CONFIG_PA20 */ 740 741 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2) 742 #define SID_ARRAY_SIZE (NR_SPACE_IDS / (8 * sizeof(long))) 743 744 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */ 745 static unsigned long dirty_space_id[SID_ARRAY_SIZE]; 746 static unsigned long space_id_index; 747 static unsigned long free_space_ids = NR_SPACE_IDS - 1; 748 static unsigned long dirty_space_ids = 0; 749 750 static DEFINE_SPINLOCK(sid_lock); 751 752 unsigned long alloc_sid(void) 753 { 754 unsigned long index; 755 756 spin_lock(&sid_lock); 757 758 if (free_space_ids == 0) { 759 if (dirty_space_ids != 0) { 760 spin_unlock(&sid_lock); 761 flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */ 762 spin_lock(&sid_lock); 763 } 764 BUG_ON(free_space_ids == 0); 765 } 766 767 free_space_ids--; 768 769 index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index); 770 space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1))); 771 space_id_index = index; 772 773 spin_unlock(&sid_lock); 774 775 return index << SPACEID_SHIFT; 776 } 777 778 void free_sid(unsigned long spaceid) 779 { 780 unsigned long index = spaceid >> SPACEID_SHIFT; 781 unsigned long *dirty_space_offset; 782 783 dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG); 784 index &= (BITS_PER_LONG - 1); 785 786 spin_lock(&sid_lock); 787 788 BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */ 789 790 *dirty_space_offset |= (1L << index); 791 dirty_space_ids++; 792 793 spin_unlock(&sid_lock); 794 } 795 796 797 #ifdef CONFIG_SMP 798 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array) 799 { 800 int i; 801 802 /* NOTE: sid_lock must be held upon entry */ 803 804 *ndirtyptr = dirty_space_ids; 805 if (dirty_space_ids != 0) { 806 for (i = 0; i < SID_ARRAY_SIZE; i++) { 807 dirty_array[i] = dirty_space_id[i]; 808 dirty_space_id[i] = 0; 809 } 810 dirty_space_ids = 0; 811 } 812 813 return; 814 } 815 816 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array) 817 { 818 int i; 819 820 /* NOTE: sid_lock must be held upon entry */ 821 822 if (ndirty != 0) { 823 for (i = 0; i < SID_ARRAY_SIZE; i++) { 824 space_id[i] ^= dirty_array[i]; 825 } 826 827 free_space_ids += ndirty; 828 space_id_index = 0; 829 } 830 } 831 832 #else /* CONFIG_SMP */ 833 834 static void recycle_sids(void) 835 { 836 int i; 837 838 /* NOTE: sid_lock must be held upon entry */ 839 840 if (dirty_space_ids != 0) { 841 for (i = 0; i < SID_ARRAY_SIZE; i++) { 842 space_id[i] ^= dirty_space_id[i]; 843 dirty_space_id[i] = 0; 844 } 845 846 free_space_ids += dirty_space_ids; 847 dirty_space_ids = 0; 848 space_id_index = 0; 849 } 850 } 851 #endif 852 853 /* 854 * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is 855 * purged, we can safely reuse the space ids that were released but 856 * not flushed from the tlb. 857 */ 858 859 #ifdef CONFIG_SMP 860 861 static unsigned long recycle_ndirty; 862 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE]; 863 static unsigned int recycle_inuse; 864 865 void flush_tlb_all(void) 866 { 867 int do_recycle; 868 869 __inc_irq_stat(irq_tlb_count); 870 do_recycle = 0; 871 spin_lock(&sid_lock); 872 if (dirty_space_ids > RECYCLE_THRESHOLD) { 873 BUG_ON(recycle_inuse); /* FIXME: Use a semaphore/wait queue here */ 874 get_dirty_sids(&recycle_ndirty,recycle_dirty_array); 875 recycle_inuse++; 876 do_recycle++; 877 } 878 spin_unlock(&sid_lock); 879 on_each_cpu(flush_tlb_all_local, NULL, 1); 880 if (do_recycle) { 881 spin_lock(&sid_lock); 882 recycle_sids(recycle_ndirty,recycle_dirty_array); 883 recycle_inuse = 0; 884 spin_unlock(&sid_lock); 885 } 886 } 887 #else 888 void flush_tlb_all(void) 889 { 890 __inc_irq_stat(irq_tlb_count); 891 spin_lock(&sid_lock); 892 flush_tlb_all_local(NULL); 893 recycle_sids(); 894 spin_unlock(&sid_lock); 895 } 896 #endif 897