arch/parisc/mm/init.c

   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