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 pmd_t pmd0[PTRS_PER_PMD] __section(".data..vm0.pmd") __attribute__ ((aligned(PAGE_SIZE)));
  41 #endif
  42
  43 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".data..vm0.pgd") __attribute__ ((aligned(PAGE_SIZE)));
  44 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __section(".data..vm0.pte") __attribute__ ((aligned(PAGE_SIZE)));
  45
  46 static struct resource data_resource = {
  47         .name   = "Kernel data",
  48         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
  49 };
  50
  51 static struct resource code_resource = {
  52         .name   = "Kernel code",
  53         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
  54 };
  55
  56 static struct resource pdcdata_resource = {
  57         .name   = "PDC data (Page Zero)",
  58         .start  = 0,
  59         .end    = 0x9ff,
  60         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
  61 };
  62
  63 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init;
  64
  65 /* The following array is initialized from the firmware specific
  66  * information retrieved in kernel/inventory.c.
  67  */
  68
  69 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata;
  70 int npmem_ranges __initdata;
  71
  72 #ifdef CONFIG_64BIT
  73 #define MAX_MEM         (1UL << MAX_PHYSMEM_BITS)
  74 #else /* !CONFIG_64BIT */
  75 #define MAX_MEM         (3584U*1024U*1024U)
  76 #endif /* !CONFIG_64BIT */
  77
  78 static unsigned long mem_limit __read_mostly = MAX_MEM;
  79
  80 static void __init mem_limit_func(void)
  81 {
  82         char *cp, *end;
  83         unsigned long limit;
  84
  85         /* We need this before __setup() functions are called */
  86
  87         limit = MAX_MEM;
  88         for (cp = boot_command_line; *cp; ) {
  89                 if (memcmp(cp, "mem=", 4) == 0) {
  90                         cp += 4;
  91                         limit = memparse(cp, &end);
  92                         if (end != cp)
  93                                 break;
  94                         cp = end;
  95                 } else {
  96                         while (*cp != ' ' && *cp)
  97                                 ++cp;
  98                         while (*cp == ' ')
  99                                 ++cp;
 100                 }
 101         }
 102
 103         if (limit < mem_limit)
 104                 mem_limit = limit;
 105 }
 106
 107 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
 108
 109 static void __init setup_bootmem(void)
 110 {
 111         unsigned long mem_max;
 112 #ifndef CONFIG_SPARSEMEM
 113         physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
 114         int npmem_holes;
 115 #endif
 116         int i, sysram_resource_count;
 117
 118         disable_sr_hashing(); /* Turn off space register hashing */
 119
 120         /*
 121          * Sort the ranges. Since the number of ranges is typically
 122          * small, and performance is not an issue here, just do
 123          * a simple insertion sort.
 124          */
 125
 126         for (i = 1; i < npmem_ranges; i++) {
 127                 int j;
 128
 129                 for (j = i; j > 0; j--) {
 130                         physmem_range_t tmp;
 131
 132                         if (pmem_ranges[j-1].start_pfn <
 133                             pmem_ranges[j].start_pfn) {
 134
 135                                 break;
 136                         }
 137                         tmp = pmem_ranges[j-1];
 138                         pmem_ranges[j-1] = pmem_ranges[j];
 139                         pmem_ranges[j] = tmp;
 140                 }
 141         }
 142
 143 #ifndef CONFIG_SPARSEMEM
 144         /*
 145          * Throw out ranges that are too far apart (controlled by
 146          * MAX_GAP).
 147          */
 148
 149         for (i = 1; i < npmem_ranges; i++) {
 150                 if (pmem_ranges[i].start_pfn -
 151                         (pmem_ranges[i-1].start_pfn +
 152                          pmem_ranges[i-1].pages) > MAX_GAP) {
 153                         npmem_ranges = i;
 154                         printk("Large gap in memory detected (%ld pages). "
 155                                "Consider turning on CONFIG_SPARSEMEM\n",
 156                                pmem_ranges[i].start_pfn -
 157                                (pmem_ranges[i-1].start_pfn +
 158                                 pmem_ranges[i-1].pages));
 159                         break;
 160                 }
 161         }
 162 #endif
 163
 164         /* Print the memory ranges */
 165         pr_info("Memory Ranges:\n");
 166
 167         for (i = 0; i < npmem_ranges; i++) {
 168                 struct resource *res = &sysram_resources[i];
 169                 unsigned long start;
 170                 unsigned long size;
 171
 172                 size = (pmem_ranges[i].pages << PAGE_SHIFT);
 173                 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
 174                 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
 175                         i, start, start + (size - 1), size >> 20);
 176
 177                 /* request memory resource */
 178                 res->name = "System RAM";
 179                 res->start = start;
 180                 res->end = start + size - 1;
 181                 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 182                 request_resource(&iomem_resource, res);
 183         }
 184
 185         sysram_resource_count = npmem_ranges;
 186
 187         /*
 188          * For 32 bit kernels we limit the amount of memory we can
 189          * support, in order to preserve enough kernel address space
 190          * for other purposes. For 64 bit kernels we don't normally
 191          * limit the memory, but this mechanism can be used to
 192          * artificially limit the amount of memory (and it is written
 193          * to work with multiple memory ranges).
 194          */
 195
 196         mem_limit_func();       /* check for "mem=" argument */
 197
 198         mem_max = 0;
 199         for (i = 0; i < npmem_ranges; i++) {
 200                 unsigned long rsize;
 201
 202                 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
 203                 if ((mem_max + rsize) > mem_limit) {
 204                         printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
 205                         if (mem_max == mem_limit)
 206                                 npmem_ranges = i;
 207                         else {
 208                                 pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
 209                                                        - (mem_max >> PAGE_SHIFT);
 210                                 npmem_ranges = i + 1;
 211                                 mem_max = mem_limit;
 212                         }
 213                         break;
 214                 }
 215                 mem_max += rsize;
 216         }
 217
 218         printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
 219
 220 #ifndef CONFIG_SPARSEMEM
 221         /* Merge the ranges, keeping track of the holes */
 222         {
 223                 unsigned long end_pfn;
 224                 unsigned long hole_pages;
 225
 226                 npmem_holes = 0;
 227                 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
 228                 for (i = 1; i < npmem_ranges; i++) {
 229
 230                         hole_pages = pmem_ranges[i].start_pfn - end_pfn;
 231                         if (hole_pages) {
 232                                 pmem_holes[npmem_holes].start_pfn = end_pfn;
 233                                 pmem_holes[npmem_holes++].pages = hole_pages;
 234                                 end_pfn += hole_pages;
 235                         }
 236                         end_pfn += pmem_ranges[i].pages;
 237                 }
 238
 239                 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
 240                 npmem_ranges = 1;
 241         }
 242 #endif
 243
 244         /*
 245          * Initialize and free the full range of memory in each range.
 246          */
 247
 248         max_pfn = 0;
 249         for (i = 0; i < npmem_ranges; i++) {
 250                 unsigned long start_pfn;
 251                 unsigned long npages;
 252                 unsigned long start;
 253                 unsigned long size;
 254
 255                 start_pfn = pmem_ranges[i].start_pfn;
 256                 npages = pmem_ranges[i].pages;
 257
 258                 start = start_pfn << PAGE_SHIFT;
 259                 size = npages << PAGE_SHIFT;
 260
 261                 /* add system RAM memblock */
 262                 memblock_add(start, size);
 263
 264                 if ((start_pfn + npages) > max_pfn)
 265                         max_pfn = start_pfn + npages;
 266         }
 267
 268         /*
 269          * We can't use memblock top-down allocations because we only
 270          * created the initial mapping up to KERNEL_INITIAL_SIZE in
 271          * the assembly bootup code.
 272          */
 273         memblock_set_bottom_up(true);
 274
 275         /* IOMMU is always used to access "high mem" on those boxes
 276          * that can support enough mem that a PCI device couldn't
 277          * directly DMA to any physical addresses.
 278          * ISA DMA support will need to revisit this.
 279          */
 280         max_low_pfn = max_pfn;
 281
 282         /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
 283
 284 #define PDC_CONSOLE_IO_IODC_SIZE 32768
 285
 286         memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
 287                                 PDC_CONSOLE_IO_IODC_SIZE));
 288         memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
 289                         (unsigned long)(_end - KERNEL_BINARY_TEXT_START));
 290
 291 #ifndef CONFIG_SPARSEMEM
 292
 293         /* reserve the holes */
 294
 295         for (i = 0; i < npmem_holes; i++) {
 296                 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
 297                                 (pmem_holes[i].pages << PAGE_SHIFT));
 298         }
 299 #endif
 300
 301 #ifdef CONFIG_BLK_DEV_INITRD
 302         if (initrd_start) {
 303                 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
 304                 if (__pa(initrd_start) < mem_max) {
 305                         unsigned long initrd_reserve;
 306
 307                         if (__pa(initrd_end) > mem_max) {
 308                                 initrd_reserve = mem_max - __pa(initrd_start);
 309                         } else {
 310                                 initrd_reserve = initrd_end - initrd_start;
 311                         }
 312                         initrd_below_start_ok = 1;
 313                         printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
 314
 315                         memblock_reserve(__pa(initrd_start), initrd_reserve);
 316                 }
 317         }
 318 #endif
 319
 320         data_resource.start =  virt_to_phys(&data_start);
 321         data_resource.end = virt_to_phys(_end) - 1;
 322         code_resource.start = virt_to_phys(_text);
 323         code_resource.end = virt_to_phys(&data_start)-1;
 324
 325         /* We don't know which region the kernel will be in, so try
 326          * all of them.
 327          */
 328         for (i = 0; i < sysram_resource_count; i++) {
 329                 struct resource *res = &sysram_resources[i];
 330                 request_resource(res, &code_resource);
 331                 request_resource(res, &data_resource);
 332         }
 333         request_resource(&sysram_resources[0], &pdcdata_resource);
 334
 335         /* Initialize Page Deallocation Table (PDT) and check for bad memory. */
 336         pdc_pdt_init();
 337
 338         memblock_allow_resize();
 339         memblock_dump_all();
 340 }
 341
 342 static bool kernel_set_to_readonly;
 343
 344 static void __ref map_pages(unsigned long start_vaddr,
 345                             unsigned long start_paddr, unsigned long size,
 346                             pgprot_t pgprot, int force)
 347 {
 348         pmd_t *pmd;
 349         pte_t *pg_table;
 350         unsigned long end_paddr;
 351         unsigned long start_pmd;
 352         unsigned long start_pte;
 353         unsigned long tmp1;
 354         unsigned long tmp2;
 355         unsigned long address;
 356         unsigned long vaddr;
 357         unsigned long ro_start;
 358         unsigned long ro_end;
 359         unsigned long kernel_start, kernel_end;
 360
 361         ro_start = __pa((unsigned long)_text);
 362         ro_end   = __pa((unsigned long)&data_start);
 363         kernel_start = __pa((unsigned long)&__init_begin);
 364         kernel_end  = __pa((unsigned long)&_end);
 365
 366         end_paddr = start_paddr + size;
 367
 368         /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */
 369         start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
 370         start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
 371
 372         address = start_paddr;
 373         vaddr = start_vaddr;
 374         while (address < end_paddr) {
 375                 pgd_t *pgd = pgd_offset_k(vaddr);
 376                 p4d_t *p4d = p4d_offset(pgd, vaddr);
 377                 pud_t *pud = pud_offset(p4d, vaddr);
 378
 379 #if CONFIG_PGTABLE_LEVELS == 3
 380                 if (pud_none(*pud)) {
 381                         pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER,
 382                                              PAGE_SIZE << PMD_TABLE_ORDER);
 383                         if (!pmd)
 384                                 panic("pmd allocation failed.\n");
 385                         pud_populate(NULL, pud, pmd);
 386                 }
 387 #endif
 388
 389                 pmd = pmd_offset(pud, vaddr);
 390                 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
 391                         if (pmd_none(*pmd)) {
 392                                 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 393                                 if (!pg_table)
 394                                         panic("page table allocation failed\n");
 395                                 pmd_populate_kernel(NULL, pmd, pg_table);
 396                         }
 397
 398                         pg_table = pte_offset_kernel(pmd, vaddr);
 399                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
 400                                 pte_t pte;
 401                                 pgprot_t prot;
 402                                 bool huge = false;
 403
 404                                 if (force) {
 405                                         prot = pgprot;
 406                                 } else if (address < kernel_start || address >= kernel_end) {
 407                                         /* outside kernel memory */
 408                                         prot = PAGE_KERNEL;
 409                                 } else if (!kernel_set_to_readonly) {
 410                                         /* still initializing, allow writing to RO memory */
 411                                         prot = PAGE_KERNEL_RWX;
 412                                         huge = true;
 413                                 } else if (address >= ro_start) {
 414                                         /* Code (ro) and Data areas */
 415                                         prot = (address < ro_end) ?
 416                                                 PAGE_KERNEL_EXEC : PAGE_KERNEL;
 417                                         huge = true;
 418                                 } else {
 419                                         prot = PAGE_KERNEL;
 420                                 }
 421
 422                                 pte = __mk_pte(address, prot);
 423                                 if (huge)
 424                                         pte = pte_mkhuge(pte);
 425
 426                                 if (address >= end_paddr)
 427                                         break;
 428
 429                                 set_pte(pg_table, pte);
 430
 431                                 address += PAGE_SIZE;
 432                                 vaddr += PAGE_SIZE;
 433                         }
 434                         start_pte = 0;
 435
 436                         if (address >= end_paddr)
 437                             break;
 438                 }
 439                 start_pmd = 0;
 440         }
 441 }
 442
 443 void __init set_kernel_text_rw(int enable_read_write)
 444 {
 445         unsigned long start = (unsigned long) __init_begin;
 446         unsigned long end   = (unsigned long) &data_start;
 447
 448         map_pages(start, __pa(start), end-start,
 449                 PAGE_KERNEL_RWX, enable_read_write ? 1:0);
 450
 451         /* force the kernel to see the new page table entries */
 452         flush_cache_all();
 453         flush_tlb_all();
 454 }
 455
 456 void free_initmem(void)
 457 {
 458         unsigned long init_begin = (unsigned long)__init_begin;
 459         unsigned long init_end = (unsigned long)__init_end;
 460         unsigned long kernel_end  = (unsigned long)&_end;
 461
 462         /* Remap kernel text and data, but do not touch init section yet. */
 463         kernel_set_to_readonly = true;
 464         map_pages(init_end, __pa(init_end), kernel_end - init_end,
 465                   PAGE_KERNEL, 0);
 466
 467         /* The init text pages are marked R-X.  We have to
 468          * flush the icache and mark them RW-
 469          *
 470          * Do a dummy remap of the data section first (the data
 471          * section is already PAGE_KERNEL) to pull in the TLB entries
 472          * for map_kernel */
 473         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
 474                   PAGE_KERNEL_RWX, 1);
 475         /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
 476          * map_pages */
 477         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
 478                   PAGE_KERNEL, 1);
 479
 480         /* force the kernel to see the new TLB entries */
 481         __flush_tlb_range(0, init_begin, kernel_end);
 482
 483         /* finally dump all the instructions which were cached, since the
 484          * pages are no-longer executable */
 485         flush_icache_range(init_begin, init_end);
 486
 487         free_initmem_default(POISON_FREE_INITMEM);
 488
 489         /* set up a new led state on systems shipped LED State panel */
 490         pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
 491 }
 492
 493
 494 #ifdef CONFIG_STRICT_KERNEL_RWX
 495 void mark_rodata_ro(void)
 496 {
 497         /* rodata memory was already mapped with KERNEL_RO access rights by
 498            pagetable_init() and map_pages(). No need to do additional stuff here */
 499         unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
 500
 501         pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
 502 }
 503 #endif
 504
 505
 506 /*
 507  * Just an arbitrary offset to serve as a "hole" between mapping areas
 508  * (between top of physical memory and a potential pcxl dma mapping
 509  * area, and below the vmalloc mapping area).
 510  *
 511  * The current 32K value just means that there will be a 32K "hole"
 512  * between mapping areas. That means that  any out-of-bounds memory
 513  * accesses will hopefully be caught. The vmalloc() routines leaves
 514  * a hole of 4kB between each vmalloced area for the same reason.
 515  */
 516
 517  /* Leave room for gateway page expansion */
 518 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
 519 #error KERNEL_MAP_START is in gateway reserved region
 520 #endif
 521 #define MAP_START (KERNEL_MAP_START)
 522
 523 #define VM_MAP_OFFSET  (32*1024)
 524 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
 525                                      & ~(VM_MAP_OFFSET-1)))
 526
 527 void *parisc_vmalloc_start __ro_after_init;
 528 EXPORT_SYMBOL(parisc_vmalloc_start);
 529
 530 #ifdef CONFIG_PA11
 531 unsigned long pcxl_dma_start __ro_after_init;
 532 #endif
 533
 534 void __init mem_init(void)
 535 {
 536         /* Do sanity checks on IPC (compat) structures */
 537         BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
 538 #ifndef CONFIG_64BIT
 539         BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
 540         BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
 541         BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
 542 #endif
 543 #ifdef CONFIG_COMPAT
 544         BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
 545         BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
 546         BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
 547         BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
 548 #endif
 549
 550         /* Do sanity checks on page table constants */
 551         BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
 552         BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
 553         BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
 554         BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
 555                         > BITS_PER_LONG);
 556 #if CONFIG_PGTABLE_LEVELS == 3
 557         BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PMD);
 558 #else
 559         BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PGD);
 560 #endif
 561
 562         high_memory = __va((max_pfn << PAGE_SHIFT));
 563         set_max_mapnr(max_low_pfn);
 564         memblock_free_all();
 565
 566 #ifdef CONFIG_PA11
 567         if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
 568                 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
 569                 parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
 570                                                 + PCXL_DMA_MAP_SIZE);
 571         } else
 572 #endif
 573                 parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
 574
 575 #if 0
 576         /*
 577          * Do not expose the virtual kernel memory layout to userspace.
 578          * But keep code for debugging purposes.
 579          */
 580         printk("virtual kernel memory layout:\n"
 581                "     vmalloc : 0x%px - 0x%px   (%4ld MB)\n"
 582                "     fixmap  : 0x%px - 0x%px   (%4ld kB)\n"
 583                "     memory  : 0x%px - 0x%px   (%4ld MB)\n"
 584                "       .init : 0x%px - 0x%px   (%4ld kB)\n"
 585                "       .data : 0x%px - 0x%px   (%4ld kB)\n"
 586                "       .text : 0x%px - 0x%px   (%4ld kB)\n",
 587
 588                (void*)VMALLOC_START, (void*)VMALLOC_END,
 589                (VMALLOC_END - VMALLOC_START) >> 20,
 590
 591                (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),
 592                (unsigned long)(FIXMAP_SIZE / 1024),
 593
 594                __va(0), high_memory,
 595                ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
 596
 597                __init_begin, __init_end,
 598                ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
 599
 600                _etext, _edata,
 601                ((unsigned long)_edata - (unsigned long)_etext) >> 10,
 602
 603                _text, _etext,
 604                ((unsigned long)_etext - (unsigned long)_text) >> 10);
 605 #endif
 606 }
 607
 608 unsigned long *empty_zero_page __ro_after_init;
 609 EXPORT_SYMBOL(empty_zero_page);
 610
 611 /*
 612  * pagetable_init() sets up the page tables
 613  *
 614  * Note that gateway_init() places the Linux gateway page at page 0.
 615  * Since gateway pages cannot be dereferenced this has the desirable
 616  * side effect of trapping those pesky NULL-reference errors in the
 617  * kernel.
 618  */
 619 static void __init pagetable_init(void)
 620 {
 621         int range;
 622
 623         /* Map each physical memory range to its kernel vaddr */
 624
 625         for (range = 0; range < npmem_ranges; range++) {
 626                 unsigned long start_paddr;
 627                 unsigned long end_paddr;
 628                 unsigned long size;
 629
 630                 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
 631                 size = pmem_ranges[range].pages << PAGE_SHIFT;
 632                 end_paddr = start_paddr + size;
 633
 634                 map_pages((unsigned long)__va(start_paddr), start_paddr,
 635                           size, PAGE_KERNEL, 0);
 636         }
 637
 638 #ifdef CONFIG_BLK_DEV_INITRD
 639         if (initrd_end && initrd_end > mem_limit) {
 640                 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
 641                 map_pages(initrd_start, __pa(initrd_start),
 642                           initrd_end - initrd_start, PAGE_KERNEL, 0);
 643         }
 644 #endif
 645
 646         empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 647         if (!empty_zero_page)
 648                 panic("zero page allocation failed.\n");
 649
 650 }
 651
 652 static void __init gateway_init(void)
 653 {
 654         unsigned long linux_gateway_page_addr;
 655         /* FIXME: This is 'const' in order to trick the compiler
 656            into not treating it as DP-relative data. */
 657         extern void * const linux_gateway_page;
 658
 659         linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
 660
 661         /*
 662          * Setup Linux Gateway page.
 663          *
 664          * The Linux gateway page will reside in kernel space (on virtual
 665          * page 0), so it doesn't need to be aliased into user space.
 666          */
 667
 668         map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
 669                   PAGE_SIZE, PAGE_GATEWAY, 1);
 670 }
 671
 672 static void __init parisc_bootmem_free(void)
 673 {
 674         unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
 675
 676         max_zone_pfn[0] = memblock_end_of_DRAM();
 677
 678         free_area_init(max_zone_pfn);
 679 }
 680
 681 void __init paging_init(void)
 682 {
 683         setup_bootmem();
 684         pagetable_init();
 685         gateway_init();
 686         flush_cache_all_local(); /* start with known state */
 687         flush_tlb_all_local(NULL);
 688
 689         sparse_init();
 690         parisc_bootmem_free();
 691 }
 692
 693 #ifdef CONFIG_PA20
 694
 695 /*
 696  * Currently, all PA20 chips have 18 bit protection IDs, which is the
 697  * limiting factor (space ids are 32 bits).
 698  */
 699
 700 #define NR_SPACE_IDS 262144
 701
 702 #else
 703
 704 /*
 705  * Currently we have a one-to-one relationship between space IDs and
 706  * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
 707  * support 15 bit protection IDs, so that is the limiting factor.
 708  * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
 709  * probably not worth the effort for a special case here.
 710  */
 711
 712 #define NR_SPACE_IDS 32768
 713
 714 #endif  /* !CONFIG_PA20 */
 715
 716 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
 717 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
 718
 719 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
 720 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
 721 static unsigned long space_id_index;
 722 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
 723 static unsigned long dirty_space_ids = 0;
 724
 725 static DEFINE_SPINLOCK(sid_lock);
 726
 727 unsigned long alloc_sid(void)
 728 {
 729         unsigned long index;
 730
 731         spin_lock(&sid_lock);
 732
 733         if (free_space_ids == 0) {
 734                 if (dirty_space_ids != 0) {
 735                         spin_unlock(&sid_lock);
 736                         flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
 737                         spin_lock(&sid_lock);
 738                 }
 739                 BUG_ON(free_space_ids == 0);
 740         }
 741
 742         free_space_ids--;
 743
 744         index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
 745         space_id[BIT_WORD(index)] |= BIT_MASK(index);
 746         space_id_index = index;
 747
 748         spin_unlock(&sid_lock);
 749
 750         return index << SPACEID_SHIFT;
 751 }
 752
 753 void free_sid(unsigned long spaceid)
 754 {
 755         unsigned long index = spaceid >> SPACEID_SHIFT;
 756         unsigned long *dirty_space_offset, mask;
 757
 758         dirty_space_offset = &dirty_space_id[BIT_WORD(index)];
 759         mask = BIT_MASK(index);
 760
 761         spin_lock(&sid_lock);
 762
 763         BUG_ON(*dirty_space_offset & mask); /* attempt to free space id twice */
 764
 765         *dirty_space_offset |= mask;
 766         dirty_space_ids++;
 767
 768         spin_unlock(&sid_lock);
 769 }
 770
 771
 772 #ifdef CONFIG_SMP
 773 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
 774 {
 775         int i;
 776
 777         /* NOTE: sid_lock must be held upon entry */
 778
 779         *ndirtyptr = dirty_space_ids;
 780         if (dirty_space_ids != 0) {
 781             for (i = 0; i < SID_ARRAY_SIZE; i++) {
 782                 dirty_array[i] = dirty_space_id[i];
 783                 dirty_space_id[i] = 0;
 784             }
 785             dirty_space_ids = 0;
 786         }
 787
 788         return;
 789 }
 790
 791 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
 792 {
 793         int i;
 794
 795         /* NOTE: sid_lock must be held upon entry */
 796
 797         if (ndirty != 0) {
 798                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
 799                         space_id[i] ^= dirty_array[i];
 800                 }
 801
 802                 free_space_ids += ndirty;
 803                 space_id_index = 0;
 804         }
 805 }
 806
 807 #else /* CONFIG_SMP */
 808
 809 static void recycle_sids(void)
 810 {
 811         int i;
 812
 813         /* NOTE: sid_lock must be held upon entry */
 814
 815         if (dirty_space_ids != 0) {
 816                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
 817                         space_id[i] ^= dirty_space_id[i];
 818                         dirty_space_id[i] = 0;
 819                 }
 820
 821                 free_space_ids += dirty_space_ids;
 822                 dirty_space_ids = 0;
 823                 space_id_index = 0;
 824         }
 825 }
 826 #endif
 827
 828 /*
 829  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
 830  * purged, we can safely reuse the space ids that were released but
 831  * not flushed from the tlb.
 832  */
 833
 834 #ifdef CONFIG_SMP
 835
 836 static unsigned long recycle_ndirty;
 837 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
 838 static unsigned int recycle_inuse;
 839
 840 void flush_tlb_all(void)
 841 {
 842         int do_recycle;
 843
 844         do_recycle = 0;
 845         spin_lock(&sid_lock);
 846         __inc_irq_stat(irq_tlb_count);
 847         if (dirty_space_ids > RECYCLE_THRESHOLD) {
 848             BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
 849             get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
 850             recycle_inuse++;
 851             do_recycle++;
 852         }
 853         spin_unlock(&sid_lock);
 854         on_each_cpu(flush_tlb_all_local, NULL, 1);
 855         if (do_recycle) {
 856             spin_lock(&sid_lock);
 857             recycle_sids(recycle_ndirty,recycle_dirty_array);
 858             recycle_inuse = 0;
 859             spin_unlock(&sid_lock);
 860         }
 861 }
 862 #else
 863 void flush_tlb_all(void)
 864 {
 865         spin_lock(&sid_lock);
 866         __inc_irq_stat(irq_tlb_count);
 867         flush_tlb_all_local(NULL);
 868         recycle_sids();
 869         spin_unlock(&sid_lock);
 870 }
 871 #endif