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/tlb.h> 30 #include <asm/pdc_chassis.h> 31 #include <asm/mmzone.h> 32 #include <asm/sections.h> 33 #include <asm/msgbuf.h> 34 #include <asm/sparsemem.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 static struct resource data_resource = { 52 .name = "Kernel data", 53 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 54 }; 55 56 static struct resource code_resource = { 57 .name = "Kernel code", 58 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, 59 }; 60 61 static struct resource pdcdata_resource = { 62 .name = "PDC data (Page Zero)", 63 .start = 0, 64 .end = 0x9ff, 65 .flags = IORESOURCE_BUSY | IORESOURCE_MEM, 66 }; 67 68 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init; 69 70 /* The following array is initialized from the firmware specific 71 * information retrieved in kernel/inventory.c. 72 */ 73 74 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata; 75 int npmem_ranges __initdata; 76 77 #ifdef CONFIG_64BIT 78 #define MAX_MEM (1UL << MAX_PHYSMEM_BITS) 79 #else /* !CONFIG_64BIT */ 80 #define MAX_MEM (3584U*1024U*1024U) 81 #endif /* !CONFIG_64BIT */ 82 83 static unsigned long mem_limit __read_mostly = MAX_MEM; 84 85 static void __init mem_limit_func(void) 86 { 87 char *cp, *end; 88 unsigned long limit; 89 90 /* We need this before __setup() functions are called */ 91 92 limit = MAX_MEM; 93 for (cp = boot_command_line; *cp; ) { 94 if (memcmp(cp, "mem=", 4) == 0) { 95 cp += 4; 96 limit = memparse(cp, &end); 97 if (end != cp) 98 break; 99 cp = end; 100 } else { 101 while (*cp != ' ' && *cp) 102 ++cp; 103 while (*cp == ' ') 104 ++cp; 105 } 106 } 107 108 if (limit < mem_limit) 109 mem_limit = limit; 110 } 111 112 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT) 113 114 static void __init setup_bootmem(void) 115 { 116 unsigned long mem_max; 117 #ifndef CONFIG_SPARSEMEM 118 physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1]; 119 int npmem_holes; 120 #endif 121 int i, sysram_resource_count; 122 123 disable_sr_hashing(); /* Turn off space register hashing */ 124 125 /* 126 * Sort the ranges. Since the number of ranges is typically 127 * small, and performance is not an issue here, just do 128 * a simple insertion sort. 129 */ 130 131 for (i = 1; i < npmem_ranges; i++) { 132 int j; 133 134 for (j = i; j > 0; j--) { 135 physmem_range_t tmp; 136 137 if (pmem_ranges[j-1].start_pfn < 138 pmem_ranges[j].start_pfn) { 139 140 break; 141 } 142 tmp = pmem_ranges[j-1]; 143 pmem_ranges[j-1] = pmem_ranges[j]; 144 pmem_ranges[j] = tmp; 145 } 146 } 147 148 #ifndef CONFIG_SPARSEMEM 149 /* 150 * Throw out ranges that are too far apart (controlled by 151 * MAX_GAP). 152 */ 153 154 for (i = 1; i < npmem_ranges; i++) { 155 if (pmem_ranges[i].start_pfn - 156 (pmem_ranges[i-1].start_pfn + 157 pmem_ranges[i-1].pages) > MAX_GAP) { 158 npmem_ranges = i; 159 printk("Large gap in memory detected (%ld pages). " 160 "Consider turning on CONFIG_SPARSEMEM\n", 161 pmem_ranges[i].start_pfn - 162 (pmem_ranges[i-1].start_pfn + 163 pmem_ranges[i-1].pages)); 164 break; 165 } 166 } 167 #endif 168 169 /* Print the memory ranges */ 170 pr_info("Memory Ranges:\n"); 171 172 for (i = 0; i < npmem_ranges; i++) { 173 struct resource *res = &sysram_resources[i]; 174 unsigned long start; 175 unsigned long size; 176 177 size = (pmem_ranges[i].pages << PAGE_SHIFT); 178 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT); 179 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n", 180 i, start, start + (size - 1), size >> 20); 181 182 /* request memory resource */ 183 res->name = "System RAM"; 184 res->start = start; 185 res->end = start + size - 1; 186 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; 187 request_resource(&iomem_resource, res); 188 } 189 190 sysram_resource_count = npmem_ranges; 191 192 /* 193 * For 32 bit kernels we limit the amount of memory we can 194 * support, in order to preserve enough kernel address space 195 * for other purposes. For 64 bit kernels we don't normally 196 * limit the memory, but this mechanism can be used to 197 * artificially limit the amount of memory (and it is written 198 * to work with multiple memory ranges). 199 */ 200 201 mem_limit_func(); /* check for "mem=" argument */ 202 203 mem_max = 0; 204 for (i = 0; i < npmem_ranges; i++) { 205 unsigned long rsize; 206 207 rsize = pmem_ranges[i].pages << PAGE_SHIFT; 208 if ((mem_max + rsize) > mem_limit) { 209 printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20); 210 if (mem_max == mem_limit) 211 npmem_ranges = i; 212 else { 213 pmem_ranges[i].pages = (mem_limit >> PAGE_SHIFT) 214 - (mem_max >> PAGE_SHIFT); 215 npmem_ranges = i + 1; 216 mem_max = mem_limit; 217 } 218 break; 219 } 220 mem_max += rsize; 221 } 222 223 printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20); 224 225 #ifndef CONFIG_SPARSEMEM 226 /* Merge the ranges, keeping track of the holes */ 227 { 228 unsigned long end_pfn; 229 unsigned long hole_pages; 230 231 npmem_holes = 0; 232 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages; 233 for (i = 1; i < npmem_ranges; i++) { 234 235 hole_pages = pmem_ranges[i].start_pfn - end_pfn; 236 if (hole_pages) { 237 pmem_holes[npmem_holes].start_pfn = end_pfn; 238 pmem_holes[npmem_holes++].pages = hole_pages; 239 end_pfn += hole_pages; 240 } 241 end_pfn += pmem_ranges[i].pages; 242 } 243 244 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn; 245 npmem_ranges = 1; 246 } 247 #endif 248 249 /* 250 * Initialize and free the full range of memory in each range. 251 */ 252 253 max_pfn = 0; 254 for (i = 0; i < npmem_ranges; i++) { 255 unsigned long start_pfn; 256 unsigned long npages; 257 unsigned long start; 258 unsigned long size; 259 260 start_pfn = pmem_ranges[i].start_pfn; 261 npages = pmem_ranges[i].pages; 262 263 start = start_pfn << PAGE_SHIFT; 264 size = npages << PAGE_SHIFT; 265 266 /* add system RAM memblock */ 267 memblock_add(start, size); 268 269 if ((start_pfn + npages) > max_pfn) 270 max_pfn = start_pfn + npages; 271 } 272 273 /* 274 * We can't use memblock top-down allocations because we only 275 * created the initial mapping up to KERNEL_INITIAL_SIZE in 276 * the assembly bootup code. 277 */ 278 memblock_set_bottom_up(true); 279 280 /* IOMMU is always used to access "high mem" on those boxes 281 * that can support enough mem that a PCI device couldn't 282 * directly DMA to any physical addresses. 283 * ISA DMA support will need to revisit this. 284 */ 285 max_low_pfn = max_pfn; 286 287 /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */ 288 289 #define PDC_CONSOLE_IO_IODC_SIZE 32768 290 291 memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free + 292 PDC_CONSOLE_IO_IODC_SIZE)); 293 memblock_reserve(__pa(KERNEL_BINARY_TEXT_START), 294 (unsigned long)(_end - KERNEL_BINARY_TEXT_START)); 295 296 #ifndef CONFIG_SPARSEMEM 297 298 /* reserve the holes */ 299 300 for (i = 0; i < npmem_holes; i++) { 301 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT), 302 (pmem_holes[i].pages << PAGE_SHIFT)); 303 } 304 #endif 305 306 #ifdef CONFIG_BLK_DEV_INITRD 307 if (initrd_start) { 308 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end); 309 if (__pa(initrd_start) < mem_max) { 310 unsigned long initrd_reserve; 311 312 if (__pa(initrd_end) > mem_max) { 313 initrd_reserve = mem_max - __pa(initrd_start); 314 } else { 315 initrd_reserve = initrd_end - initrd_start; 316 } 317 initrd_below_start_ok = 1; 318 printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max); 319 320 memblock_reserve(__pa(initrd_start), initrd_reserve); 321 } 322 } 323 #endif 324 325 data_resource.start = virt_to_phys(&data_start); 326 data_resource.end = virt_to_phys(_end) - 1; 327 code_resource.start = virt_to_phys(_text); 328 code_resource.end = virt_to_phys(&data_start)-1; 329 330 /* We don't know which region the kernel will be in, so try 331 * all of them. 332 */ 333 for (i = 0; i < sysram_resource_count; i++) { 334 struct resource *res = &sysram_resources[i]; 335 request_resource(res, &code_resource); 336 request_resource(res, &data_resource); 337 } 338 request_resource(&sysram_resources[0], &pdcdata_resource); 339 340 /* Initialize Page Deallocation Table (PDT) and check for bad memory. */ 341 pdc_pdt_init(); 342 343 memblock_allow_resize(); 344 memblock_dump_all(); 345 } 346 347 static bool kernel_set_to_readonly; 348 349 static void __init map_pages(unsigned long start_vaddr, 350 unsigned long start_paddr, unsigned long size, 351 pgprot_t pgprot, int force) 352 { 353 pmd_t *pmd; 354 pte_t *pg_table; 355 unsigned long end_paddr; 356 unsigned long start_pmd; 357 unsigned long start_pte; 358 unsigned long tmp1; 359 unsigned long tmp2; 360 unsigned long address; 361 unsigned long vaddr; 362 unsigned long ro_start; 363 unsigned long ro_end; 364 unsigned long kernel_start, kernel_end; 365 366 ro_start = __pa((unsigned long)_text); 367 ro_end = __pa((unsigned long)&data_start); 368 kernel_start = __pa((unsigned long)&__init_begin); 369 kernel_end = __pa((unsigned long)&_end); 370 371 end_paddr = start_paddr + size; 372 373 /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */ 374 start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1)); 375 start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)); 376 377 address = start_paddr; 378 vaddr = start_vaddr; 379 while (address < end_paddr) { 380 pgd_t *pgd = pgd_offset_k(vaddr); 381 p4d_t *p4d = p4d_offset(pgd, vaddr); 382 pud_t *pud = pud_offset(p4d, vaddr); 383 384 #if CONFIG_PGTABLE_LEVELS == 3 385 if (pud_none(*pud)) { 386 pmd = memblock_alloc(PAGE_SIZE << PMD_ORDER, 387 PAGE_SIZE << PMD_ORDER); 388 if (!pmd) 389 panic("pmd allocation failed.\n"); 390 pud_populate(NULL, pud, pmd); 391 } 392 #endif 393 394 pmd = pmd_offset(pud, vaddr); 395 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) { 396 if (pmd_none(*pmd)) { 397 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE); 398 if (!pg_table) 399 panic("page table allocation failed\n"); 400 pmd_populate_kernel(NULL, pmd, pg_table); 401 } 402 403 pg_table = pte_offset_kernel(pmd, vaddr); 404 for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) { 405 pte_t pte; 406 pgprot_t prot; 407 bool huge = false; 408 409 if (force) { 410 prot = pgprot; 411 } else if (address < kernel_start || address >= kernel_end) { 412 /* outside kernel memory */ 413 prot = PAGE_KERNEL; 414 } else if (!kernel_set_to_readonly) { 415 /* still initializing, allow writing to RO memory */ 416 prot = PAGE_KERNEL_RWX; 417 huge = true; 418 } else if (address >= ro_start) { 419 /* Code (ro) and Data areas */ 420 prot = (address < ro_end) ? 421 PAGE_KERNEL_EXEC : PAGE_KERNEL; 422 huge = true; 423 } else { 424 prot = PAGE_KERNEL; 425 } 426 427 pte = __mk_pte(address, prot); 428 if (huge) 429 pte = pte_mkhuge(pte); 430 431 if (address >= end_paddr) 432 break; 433 434 set_pte(pg_table, pte); 435 436 address += PAGE_SIZE; 437 vaddr += PAGE_SIZE; 438 } 439 start_pte = 0; 440 441 if (address >= end_paddr) 442 break; 443 } 444 start_pmd = 0; 445 } 446 } 447 448 void __init set_kernel_text_rw(int enable_read_write) 449 { 450 unsigned long start = (unsigned long) __init_begin; 451 unsigned long end = (unsigned long) &data_start; 452 453 map_pages(start, __pa(start), end-start, 454 PAGE_KERNEL_RWX, enable_read_write ? 1:0); 455 456 /* force the kernel to see the new page table entries */ 457 flush_cache_all(); 458 flush_tlb_all(); 459 } 460 461 void __ref free_initmem(void) 462 { 463 unsigned long init_begin = (unsigned long)__init_begin; 464 unsigned long init_end = (unsigned long)__init_end; 465 unsigned long kernel_end = (unsigned long)&_end; 466 467 /* Remap kernel text and data, but do not touch init section yet. */ 468 kernel_set_to_readonly = true; 469 map_pages(init_end, __pa(init_end), kernel_end - init_end, 470 PAGE_KERNEL, 0); 471 472 /* The init text pages are marked R-X. We have to 473 * flush the icache and mark them RW- 474 * 475 * This is tricky, because map_pages is in the init section. 476 * Do a dummy remap of the data section first (the data 477 * section is already PAGE_KERNEL) to pull in the TLB entries 478 * for map_kernel */ 479 map_pages(init_begin, __pa(init_begin), init_end - init_begin, 480 PAGE_KERNEL_RWX, 1); 481 /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute 482 * map_pages */ 483 map_pages(init_begin, __pa(init_begin), init_end - init_begin, 484 PAGE_KERNEL, 1); 485 486 /* force the kernel to see the new TLB entries */ 487 __flush_tlb_range(0, init_begin, kernel_end); 488 489 /* finally dump all the instructions which were cached, since the 490 * pages are no-longer executable */ 491 flush_icache_range(init_begin, init_end); 492 493 free_initmem_default(POISON_FREE_INITMEM); 494 495 /* set up a new led state on systems shipped LED State panel */ 496 pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE); 497 } 498 499 500 #ifdef CONFIG_STRICT_KERNEL_RWX 501 void mark_rodata_ro(void) 502 { 503 /* rodata memory was already mapped with KERNEL_RO access rights by 504 pagetable_init() and map_pages(). No need to do additional stuff here */ 505 unsigned long roai_size = __end_ro_after_init - __start_ro_after_init; 506 507 pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10); 508 } 509 #endif 510 511 512 /* 513 * Just an arbitrary offset to serve as a "hole" between mapping areas 514 * (between top of physical memory and a potential pcxl dma mapping 515 * area, and below the vmalloc mapping area). 516 * 517 * The current 32K value just means that there will be a 32K "hole" 518 * between mapping areas. That means that any out-of-bounds memory 519 * accesses will hopefully be caught. The vmalloc() routines leaves 520 * a hole of 4kB between each vmalloced area for the same reason. 521 */ 522 523 /* Leave room for gateway page expansion */ 524 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE 525 #error KERNEL_MAP_START is in gateway reserved region 526 #endif 527 #define MAP_START (KERNEL_MAP_START) 528 529 #define VM_MAP_OFFSET (32*1024) 530 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \ 531 & ~(VM_MAP_OFFSET-1))) 532 533 void *parisc_vmalloc_start __ro_after_init; 534 EXPORT_SYMBOL(parisc_vmalloc_start); 535 536 #ifdef CONFIG_PA11 537 unsigned long pcxl_dma_start __ro_after_init; 538 #endif 539 540 void __init mem_init(void) 541 { 542 /* Do sanity checks on IPC (compat) structures */ 543 BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48); 544 #ifndef CONFIG_64BIT 545 BUILD_BUG_ON(sizeof(struct semid64_ds) != 80); 546 BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104); 547 BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104); 548 #endif 549 #ifdef CONFIG_COMPAT 550 BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm)); 551 BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80); 552 BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104); 553 BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104); 554 #endif 555 556 /* Do sanity checks on page table constants */ 557 BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t)); 558 BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t)); 559 BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t)); 560 BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD 561 > BITS_PER_LONG); 562 563 high_memory = __va((max_pfn << PAGE_SHIFT)); 564 set_max_mapnr(max_low_pfn); 565 memblock_free_all(); 566 567 #ifdef CONFIG_PA11 568 if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) { 569 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START); 570 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start 571 + PCXL_DMA_MAP_SIZE); 572 } else 573 #endif 574 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START); 575 576 mem_init_print_info(NULL); 577 578 #if 0 579 /* 580 * Do not expose the virtual kernel memory layout to userspace. 581 * But keep code for debugging purposes. 582 */ 583 printk("virtual kernel memory layout:\n" 584 " vmalloc : 0x%px - 0x%px (%4ld MB)\n" 585 " fixmap : 0x%px - 0x%px (%4ld kB)\n" 586 " memory : 0x%px - 0x%px (%4ld MB)\n" 587 " .init : 0x%px - 0x%px (%4ld kB)\n" 588 " .data : 0x%px - 0x%px (%4ld kB)\n" 589 " .text : 0x%px - 0x%px (%4ld kB)\n", 590 591 (void*)VMALLOC_START, (void*)VMALLOC_END, 592 (VMALLOC_END - VMALLOC_START) >> 20, 593 594 (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE), 595 (unsigned long)(FIXMAP_SIZE / 1024), 596 597 __va(0), high_memory, 598 ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20, 599 600 __init_begin, __init_end, 601 ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10, 602 603 _etext, _edata, 604 ((unsigned long)_edata - (unsigned long)_etext) >> 10, 605 606 _text, _etext, 607 ((unsigned long)_etext - (unsigned long)_text) >> 10); 608 #endif 609 } 610 611 unsigned long *empty_zero_page __ro_after_init; 612 EXPORT_SYMBOL(empty_zero_page); 613 614 /* 615 * pagetable_init() sets up the page tables 616 * 617 * Note that gateway_init() places the Linux gateway page at page 0. 618 * Since gateway pages cannot be dereferenced this has the desirable 619 * side effect of trapping those pesky NULL-reference errors in the 620 * kernel. 621 */ 622 static void __init pagetable_init(void) 623 { 624 int range; 625 626 /* Map each physical memory range to its kernel vaddr */ 627 628 for (range = 0; range < npmem_ranges; range++) { 629 unsigned long start_paddr; 630 unsigned long end_paddr; 631 unsigned long size; 632 633 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT; 634 size = pmem_ranges[range].pages << PAGE_SHIFT; 635 end_paddr = start_paddr + size; 636 637 map_pages((unsigned long)__va(start_paddr), start_paddr, 638 size, PAGE_KERNEL, 0); 639 } 640 641 #ifdef CONFIG_BLK_DEV_INITRD 642 if (initrd_end && initrd_end > mem_limit) { 643 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end); 644 map_pages(initrd_start, __pa(initrd_start), 645 initrd_end - initrd_start, PAGE_KERNEL, 0); 646 } 647 #endif 648 649 empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE); 650 if (!empty_zero_page) 651 panic("zero page allocation failed.\n"); 652 653 } 654 655 static void __init gateway_init(void) 656 { 657 unsigned long linux_gateway_page_addr; 658 /* FIXME: This is 'const' in order to trick the compiler 659 into not treating it as DP-relative data. */ 660 extern void * const linux_gateway_page; 661 662 linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK; 663 664 /* 665 * Setup Linux Gateway page. 666 * 667 * The Linux gateway page will reside in kernel space (on virtual 668 * page 0), so it doesn't need to be aliased into user space. 669 */ 670 671 map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page), 672 PAGE_SIZE, PAGE_GATEWAY, 1); 673 } 674 675 static void __init parisc_bootmem_free(void) 676 { 677 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, }; 678 679 max_zone_pfn[0] = memblock_end_of_DRAM(); 680 681 free_area_init(max_zone_pfn); 682 } 683 684 void __init paging_init(void) 685 { 686 setup_bootmem(); 687 pagetable_init(); 688 gateway_init(); 689 flush_cache_all_local(); /* start with known state */ 690 flush_tlb_all_local(NULL); 691 692 sparse_init(); 693 parisc_bootmem_free(); 694 } 695 696 #ifdef CONFIG_PA20 697 698 /* 699 * Currently, all PA20 chips have 18 bit protection IDs, which is the 700 * limiting factor (space ids are 32 bits). 701 */ 702 703 #define NR_SPACE_IDS 262144 704 705 #else 706 707 /* 708 * Currently we have a one-to-one relationship between space IDs and 709 * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only 710 * support 15 bit protection IDs, so that is the limiting factor. 711 * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's 712 * probably not worth the effort for a special case here. 713 */ 714 715 #define NR_SPACE_IDS 32768 716 717 #endif /* !CONFIG_PA20 */ 718 719 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2) 720 #define SID_ARRAY_SIZE (NR_SPACE_IDS / (8 * sizeof(long))) 721 722 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */ 723 static unsigned long dirty_space_id[SID_ARRAY_SIZE]; 724 static unsigned long space_id_index; 725 static unsigned long free_space_ids = NR_SPACE_IDS - 1; 726 static unsigned long dirty_space_ids = 0; 727 728 static DEFINE_SPINLOCK(sid_lock); 729 730 unsigned long alloc_sid(void) 731 { 732 unsigned long index; 733 734 spin_lock(&sid_lock); 735 736 if (free_space_ids == 0) { 737 if (dirty_space_ids != 0) { 738 spin_unlock(&sid_lock); 739 flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */ 740 spin_lock(&sid_lock); 741 } 742 BUG_ON(free_space_ids == 0); 743 } 744 745 free_space_ids--; 746 747 index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index); 748 space_id[BIT_WORD(index)] |= BIT_MASK(index); 749 space_id_index = index; 750 751 spin_unlock(&sid_lock); 752 753 return index << SPACEID_SHIFT; 754 } 755 756 void free_sid(unsigned long spaceid) 757 { 758 unsigned long index = spaceid >> SPACEID_SHIFT; 759 unsigned long *dirty_space_offset, mask; 760 761 dirty_space_offset = &dirty_space_id[BIT_WORD(index)]; 762 mask = BIT_MASK(index); 763 764 spin_lock(&sid_lock); 765 766 BUG_ON(*dirty_space_offset & mask); /* attempt to free space id twice */ 767 768 *dirty_space_offset |= mask; 769 dirty_space_ids++; 770 771 spin_unlock(&sid_lock); 772 } 773 774 775 #ifdef CONFIG_SMP 776 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array) 777 { 778 int i; 779 780 /* NOTE: sid_lock must be held upon entry */ 781 782 *ndirtyptr = dirty_space_ids; 783 if (dirty_space_ids != 0) { 784 for (i = 0; i < SID_ARRAY_SIZE; i++) { 785 dirty_array[i] = dirty_space_id[i]; 786 dirty_space_id[i] = 0; 787 } 788 dirty_space_ids = 0; 789 } 790 791 return; 792 } 793 794 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array) 795 { 796 int i; 797 798 /* NOTE: sid_lock must be held upon entry */ 799 800 if (ndirty != 0) { 801 for (i = 0; i < SID_ARRAY_SIZE; i++) { 802 space_id[i] ^= dirty_array[i]; 803 } 804 805 free_space_ids += ndirty; 806 space_id_index = 0; 807 } 808 } 809 810 #else /* CONFIG_SMP */ 811 812 static void recycle_sids(void) 813 { 814 int i; 815 816 /* NOTE: sid_lock must be held upon entry */ 817 818 if (dirty_space_ids != 0) { 819 for (i = 0; i < SID_ARRAY_SIZE; i++) { 820 space_id[i] ^= dirty_space_id[i]; 821 dirty_space_id[i] = 0; 822 } 823 824 free_space_ids += dirty_space_ids; 825 dirty_space_ids = 0; 826 space_id_index = 0; 827 } 828 } 829 #endif 830 831 /* 832 * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is 833 * purged, we can safely reuse the space ids that were released but 834 * not flushed from the tlb. 835 */ 836 837 #ifdef CONFIG_SMP 838 839 static unsigned long recycle_ndirty; 840 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE]; 841 static unsigned int recycle_inuse; 842 843 void flush_tlb_all(void) 844 { 845 int do_recycle; 846 847 __inc_irq_stat(irq_tlb_count); 848 do_recycle = 0; 849 spin_lock(&sid_lock); 850 if (dirty_space_ids > RECYCLE_THRESHOLD) { 851 BUG_ON(recycle_inuse); /* FIXME: Use a semaphore/wait queue here */ 852 get_dirty_sids(&recycle_ndirty,recycle_dirty_array); 853 recycle_inuse++; 854 do_recycle++; 855 } 856 spin_unlock(&sid_lock); 857 on_each_cpu(flush_tlb_all_local, NULL, 1); 858 if (do_recycle) { 859 spin_lock(&sid_lock); 860 recycle_sids(recycle_ndirty,recycle_dirty_array); 861 recycle_inuse = 0; 862 spin_unlock(&sid_lock); 863 } 864 } 865 #else 866 void flush_tlb_all(void) 867 { 868 __inc_irq_stat(irq_tlb_count); 869 spin_lock(&sid_lock); 870 flush_tlb_all_local(NULL); 871 recycle_sids(); 872 spin_unlock(&sid_lock); 873 } 874 #endif 875