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 ([email protected])
   9  *  Copyright 2004 Randolph Chung ([email protected])
  10  *  Copyright 2006-2007 Helge Deller ([email protected])
  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 #include <linux/execmem.h>
  28
  29 #include <asm/pgalloc.h>
  30 #include <asm/tlb.h>
  31 #include <asm/pdc_chassis.h>
  32 #include <asm/mmzone.h>
  33 #include <asm/sections.h>
  34 #include <asm/msgbuf.h>
  35 #include <asm/sparsemem.h>
  36 #include <asm/asm-offsets.h>
  37 #include <asm/shmbuf.h>
  38
  39 extern int  data_start;
  40 extern void parisc_kernel_start(void);  /* Kernel entry point in head.S */
  41
  42 #if CONFIG_PGTABLE_LEVELS == 3
  43 pmd_t pmd0[PTRS_PER_PMD] __section(".data..vm0.pmd") __attribute__ ((aligned(PAGE_SIZE)));
  44 #endif
  45
  46 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".data..vm0.pgd") __attribute__ ((aligned(PAGE_SIZE)));
  47 pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __section(".data..vm0.pte") __attribute__ ((aligned(PAGE_SIZE)));
  48
  49 static struct resource data_resource = {
  50         .name   = "Kernel data",
  51         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
  52 };
  53
  54 static struct resource code_resource = {
  55         .name   = "Kernel code",
  56         .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
  57 };
  58
  59 static struct resource pdcdata_resource = {
  60         .name   = "PDC data (Page Zero)",
  61         .start  = 0,
  62         .end    = 0x9ff,
  63         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
  64 };
  65
  66 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init;
  67
  68 /* The following array is initialized from the firmware specific
  69  * information retrieved in kernel/inventory.c.
  70  */
  71
  72 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata;
  73 int npmem_ranges __initdata;
  74
  75 #ifdef CONFIG_64BIT
  76 #define MAX_MEM         (1UL << MAX_PHYSMEM_BITS)
  77 #else /* !CONFIG_64BIT */
  78 #define MAX_MEM         (3584U*1024U*1024U)
  79 #endif /* !CONFIG_64BIT */
  80
  81 static unsigned long mem_limit __read_mostly = MAX_MEM;
  82
  83 static void __init mem_limit_func(void)
  84 {
  85         char *cp, *end;
  86         unsigned long limit;
  87
  88         /* We need this before __setup() functions are called */
  89
  90         limit = MAX_MEM;
  91         for (cp = boot_command_line; *cp; ) {
  92                 if (memcmp(cp, "mem=", 4) == 0) {
  93                         cp += 4;
  94                         limit = memparse(cp, &end);
  95                         if (end != cp)
  96                                 break;
  97                         cp = end;
  98                 } else {
  99                         while (*cp != ' ' && *cp)
 100                                 ++cp;
 101                         while (*cp == ' ')
 102                                 ++cp;
 103                 }
 104         }
 105
 106         if (limit < mem_limit)
 107                 mem_limit = limit;
 108 }
 109
 110 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
 111
 112 static void __init setup_bootmem(void)
 113 {
 114         unsigned long mem_max;
 115 #ifndef CONFIG_SPARSEMEM
 116         physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
 117         int npmem_holes;
 118 #endif
 119         int i, sysram_resource_count;
 120
 121         disable_sr_hashing(); /* Turn off space register hashing */
 122
 123         /*
 124          * Sort the ranges. Since the number of ranges is typically
 125          * small, and performance is not an issue here, just do
 126          * a simple insertion sort.
 127          */
 128
 129         for (i = 1; i < npmem_ranges; i++) {
 130                 int j;
 131
 132                 for (j = i; j > 0; j--) {
 133                         if (pmem_ranges[j-1].start_pfn <
 134                             pmem_ranges[j].start_pfn) {
 135
 136                                 break;
 137                         }
 138                         swap(pmem_ranges[j-1], pmem_ranges[j]);
 139                 }
 140         }
 141
 142 #ifndef CONFIG_SPARSEMEM
 143         /*
 144          * Throw out ranges that are too far apart (controlled by
 145          * MAX_GAP).
 146          */
 147
 148         for (i = 1; i < npmem_ranges; i++) {
 149                 if (pmem_ranges[i].start_pfn -
 150                         (pmem_ranges[i-1].start_pfn +
 151                          pmem_ranges[i-1].pages) > MAX_GAP) {
 152                         npmem_ranges = i;
 153                         printk("Large gap in memory detected (%ld pages). "
 154                                "Consider turning on CONFIG_SPARSEMEM\n",
 155                                pmem_ranges[i].start_pfn -
 156                                (pmem_ranges[i-1].start_pfn +
 157                                 pmem_ranges[i-1].pages));
 158                         break;
 159                 }
 160         }
 161 #endif
 162
 163         /* Print the memory ranges */
 164         pr_info("Memory Ranges:\n");
 165
 166         for (i = 0; i < npmem_ranges; i++) {
 167                 struct resource *res = &sysram_resources[i];
 168                 unsigned long start;
 169                 unsigned long size;
 170
 171                 size = (pmem_ranges[i].pages << PAGE_SHIFT);
 172                 start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
 173                 pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
 174                         i, start, start + (size - 1), size >> 20);
 175
 176                 /* request memory resource */
 177                 res->name = "System RAM";
 178                 res->start = start;
 179                 res->end = start + size - 1;
 180                 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 181                 request_resource(&iomem_resource, res);
 182         }
 183
 184         sysram_resource_count = npmem_ranges;
 185
 186         /*
 187          * For 32 bit kernels we limit the amount of memory we can
 188          * support, in order to preserve enough kernel address space
 189          * for other purposes. For 64 bit kernels we don't normally
 190          * limit the memory, but this mechanism can be used to
 191          * artificially limit the amount of memory (and it is written
 192          * to work with multiple memory ranges).
 193          */
 194
 195         mem_limit_func();       /* check for "mem=" argument */
 196
 197         mem_max = 0;
 198         for (i = 0; i < npmem_ranges; i++) {
 199                 unsigned long rsize;
 200
 201                 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
 202                 if ((mem_max + rsize) > mem_limit) {
 203                         printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
 204                         if (mem_max == mem_limit)
 205                                 npmem_ranges = i;
 206                         else {
 207                                 pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
 208                                                        - (mem_max >> PAGE_SHIFT);
 209                                 npmem_ranges = i + 1;
 210                                 mem_max = mem_limit;
 211                         }
 212                         break;
 213                 }
 214                 mem_max += rsize;
 215         }
 216
 217         printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
 218
 219 #ifndef CONFIG_SPARSEMEM
 220         /* Merge the ranges, keeping track of the holes */
 221         {
 222                 unsigned long end_pfn;
 223                 unsigned long hole_pages;
 224
 225                 npmem_holes = 0;
 226                 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
 227                 for (i = 1; i < npmem_ranges; i++) {
 228
 229                         hole_pages = pmem_ranges[i].start_pfn - end_pfn;
 230                         if (hole_pages) {
 231                                 pmem_holes[npmem_holes].start_pfn = end_pfn;
 232                                 pmem_holes[npmem_holes++].pages = hole_pages;
 233                                 end_pfn += hole_pages;
 234                         }
 235                         end_pfn += pmem_ranges[i].pages;
 236                 }
 237
 238                 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
 239                 npmem_ranges = 1;
 240         }
 241 #endif
 242
 243         /*
 244          * Initialize and free the full range of memory in each range.
 245          */
 246
 247         max_pfn = 0;
 248         for (i = 0; i < npmem_ranges; i++) {
 249                 unsigned long start_pfn;
 250                 unsigned long npages;
 251                 unsigned long start;
 252                 unsigned long size;
 253
 254                 start_pfn = pmem_ranges[i].start_pfn;
 255                 npages = pmem_ranges[i].pages;
 256
 257                 start = start_pfn << PAGE_SHIFT;
 258                 size = npages << PAGE_SHIFT;
 259
 260                 /* add system RAM memblock */
 261                 memblock_add(start, size);
 262
 263                 if ((start_pfn + npages) > max_pfn)
 264                         max_pfn = start_pfn + npages;
 265         }
 266
 267         /*
 268          * We can't use memblock top-down allocations because we only
 269          * created the initial mapping up to KERNEL_INITIAL_SIZE in
 270          * the assembly bootup code.
 271          */
 272         memblock_set_bottom_up(true);
 273
 274         /* IOMMU is always used to access "high mem" on those boxes
 275          * that can support enough mem that a PCI device couldn't
 276          * directly DMA to any physical addresses.
 277          * ISA DMA support will need to revisit this.
 278          */
 279         max_low_pfn = max_pfn;
 280
 281         /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
 282
 283 #define PDC_CONSOLE_IO_IODC_SIZE 32768
 284
 285         memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free +
 286                                 PDC_CONSOLE_IO_IODC_SIZE));
 287         memblock_reserve(__pa(KERNEL_BINARY_TEXT_START),
 288                         (unsigned long)(_end - KERNEL_BINARY_TEXT_START));
 289
 290 #ifndef CONFIG_SPARSEMEM
 291
 292         /* reserve the holes */
 293
 294         for (i = 0; i < npmem_holes; i++) {
 295                 memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT),
 296                                 (pmem_holes[i].pages << PAGE_SHIFT));
 297         }
 298 #endif
 299
 300 #ifdef CONFIG_BLK_DEV_INITRD
 301         if (initrd_start) {
 302                 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
 303                 if (__pa(initrd_start) < mem_max) {
 304                         unsigned long initrd_reserve;
 305
 306                         if (__pa(initrd_end) > mem_max) {
 307                                 initrd_reserve = mem_max - __pa(initrd_start);
 308                         } else {
 309                                 initrd_reserve = initrd_end - initrd_start;
 310                         }
 311                         initrd_below_start_ok = 1;
 312                         printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
 313
 314                         memblock_reserve(__pa(initrd_start), initrd_reserve);
 315                 }
 316         }
 317 #endif
 318
 319         data_resource.start =  virt_to_phys(&data_start);
 320         data_resource.end = virt_to_phys(_end) - 1;
 321         code_resource.start = virt_to_phys(_text);
 322         code_resource.end = virt_to_phys(&data_start)-1;
 323
 324         /* We don't know which region the kernel will be in, so try
 325          * all of them.
 326          */
 327         for (i = 0; i < sysram_resource_count; i++) {
 328                 struct resource *res = &sysram_resources[i];
 329                 request_resource(res, &code_resource);
 330                 request_resource(res, &data_resource);
 331         }
 332         request_resource(&sysram_resources[0], &pdcdata_resource);
 333
 334         /* Initialize Page Deallocation Table (PDT) and check for bad memory. */
 335         pdc_pdt_init();
 336
 337         memblock_allow_resize();
 338         memblock_dump_all();
 339 }
 340
 341 static bool kernel_set_to_readonly;
 342
 343 static void __ref map_pages(unsigned long start_vaddr,
 344                             unsigned long start_paddr, unsigned long size,
 345                             pgprot_t pgprot, int force)
 346 {
 347         pmd_t *pmd;
 348         pte_t *pg_table;
 349         unsigned long end_paddr;
 350         unsigned long start_pmd;
 351         unsigned long start_pte;
 352         unsigned long tmp1;
 353         unsigned long tmp2;
 354         unsigned long address;
 355         unsigned long vaddr;
 356         unsigned long ro_start;
 357         unsigned long ro_end;
 358         unsigned long kernel_start, kernel_end;
 359
 360         ro_start = __pa((unsigned long)_text);
 361         ro_end   = __pa((unsigned long)&data_start);
 362         kernel_start = __pa((unsigned long)&__init_begin);
 363         kernel_end  = __pa((unsigned long)&_end);
 364
 365         end_paddr = start_paddr + size;
 366
 367         /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */
 368         start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
 369         start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
 370
 371         address = start_paddr;
 372         vaddr = start_vaddr;
 373         while (address < end_paddr) {
 374                 pgd_t *pgd = pgd_offset_k(vaddr);
 375                 p4d_t *p4d = p4d_offset(pgd, vaddr);
 376                 pud_t *pud = pud_offset(p4d, vaddr);
 377
 378 #if CONFIG_PGTABLE_LEVELS == 3
 379                 if (pud_none(*pud)) {
 380                         pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER,
 381                                              PAGE_SIZE << PMD_TABLE_ORDER);
 382                         if (!pmd)
 383                                 panic("pmd allocation failed.\n");
 384                         pud_populate(NULL, pud, pmd);
 385                 }
 386 #endif
 387
 388                 pmd = pmd_offset(pud, vaddr);
 389                 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) {
 390                         if (pmd_none(*pmd)) {
 391                                 pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 392                                 if (!pg_table)
 393                                         panic("page table allocation failed\n");
 394                                 pmd_populate_kernel(NULL, pmd, pg_table);
 395                         }
 396
 397                         pg_table = pte_offset_kernel(pmd, vaddr);
 398                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) {
 399                                 pte_t pte;
 400                                 pgprot_t prot;
 401                                 bool huge = false;
 402
 403                                 if (force) {
 404                                         prot = pgprot;
 405                                 } else if (address < kernel_start || address >= kernel_end) {
 406                                         /* outside kernel memory */
 407                                         prot = PAGE_KERNEL;
 408                                 } else if (!kernel_set_to_readonly) {
 409                                         /* still initializing, allow writing to RO memory */
 410                                         prot = PAGE_KERNEL_RWX;
 411                                         huge = true;
 412                                 } else if (address >= ro_start) {
 413                                         /* Code (ro) and Data areas */
 414                                         prot = (address < ro_end) ?
 415                                                 PAGE_KERNEL_EXEC : PAGE_KERNEL;
 416                                         huge = true;
 417                                 } else {
 418                                         prot = PAGE_KERNEL;
 419                                 }
 420
 421                                 pte = __mk_pte(address, prot);
 422                                 if (huge)
 423                                         pte = pte_mkhuge(pte);
 424
 425                                 if (address >= end_paddr)
 426                                         break;
 427
 428                                 set_pte(pg_table, pte);
 429
 430                                 address += PAGE_SIZE;
 431                                 vaddr += PAGE_SIZE;
 432                         }
 433                         start_pte = 0;
 434
 435                         if (address >= end_paddr)
 436                             break;
 437                 }
 438                 start_pmd = 0;
 439         }
 440 }
 441
 442 void __init set_kernel_text_rw(int enable_read_write)
 443 {
 444         unsigned long start = (unsigned long) __init_begin;
 445         unsigned long end   = (unsigned long) &data_start;
 446
 447         map_pages(start, __pa(start), end-start,
 448                 PAGE_KERNEL_RWX, enable_read_write ? 1:0);
 449
 450         /* force the kernel to see the new page table entries */
 451         flush_cache_all();
 452         flush_tlb_all();
 453 }
 454
 455 void free_initmem(void)
 456 {
 457         unsigned long init_begin = (unsigned long)__init_begin;
 458         unsigned long init_end = (unsigned long)__init_end;
 459         unsigned long kernel_end  = (unsigned long)&_end;
 460
 461         /* Remap kernel text and data, but do not touch init section yet. */
 462         kernel_set_to_readonly = true;
 463         map_pages(init_end, __pa(init_end), kernel_end - init_end,
 464                   PAGE_KERNEL, 0);
 465
 466         /* The init text pages are marked R-X.  We have to
 467          * flush the icache and mark them RW-
 468          *
 469          * Do a dummy remap of the data section first (the data
 470          * section is already PAGE_KERNEL) to pull in the TLB entries
 471          * for map_kernel */
 472         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
 473                   PAGE_KERNEL_RWX, 1);
 474         /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute
 475          * map_pages */
 476         map_pages(init_begin, __pa(init_begin), init_end - init_begin,
 477                   PAGE_KERNEL, 1);
 478
 479         /* force the kernel to see the new TLB entries */
 480         __flush_tlb_range(0, init_begin, kernel_end);
 481
 482         /* finally dump all the instructions which were cached, since the
 483          * pages are no-longer executable */
 484         flush_icache_range(init_begin, init_end);
 485
 486         free_initmem_default(POISON_FREE_INITMEM);
 487
 488         /* set up a new led state on systems shipped LED State panel */
 489         pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
 490 }
 491
 492
 493 #ifdef CONFIG_STRICT_KERNEL_RWX
 494 void mark_rodata_ro(void)
 495 {
 496         /* rodata memory was already mapped with KERNEL_RO access rights by
 497            pagetable_init() and map_pages(). No need to do additional stuff here */
 498         unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
 499
 500         pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
 501 }
 502 #endif
 503
 504
 505 /*
 506  * Just an arbitrary offset to serve as a "hole" between mapping areas
 507  * (between top of physical memory and a potential pcxl dma mapping
 508  * area, and below the vmalloc mapping area).
 509  *
 510  * The current 32K value just means that there will be a 32K "hole"
 511  * between mapping areas. That means that  any out-of-bounds memory
 512  * accesses will hopefully be caught. The vmalloc() routines leaves
 513  * a hole of 4kB between each vmalloced area for the same reason.
 514  */
 515
 516  /* Leave room for gateway page expansion */
 517 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
 518 #error KERNEL_MAP_START is in gateway reserved region
 519 #endif
 520 #define MAP_START (KERNEL_MAP_START)
 521
 522 #define VM_MAP_OFFSET  (32*1024)
 523 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
 524                                      & ~(VM_MAP_OFFSET-1)))
 525
 526 void *parisc_vmalloc_start __ro_after_init;
 527 EXPORT_SYMBOL(parisc_vmalloc_start);
 528
 529 void __init mem_init(void)
 530 {
 531         /* Do sanity checks on IPC (compat) structures */
 532         BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48);
 533 #ifndef CONFIG_64BIT
 534         BUILD_BUG_ON(sizeof(struct semid64_ds) != 80);
 535         BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104);
 536         BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104);
 537 #endif
 538 #ifdef CONFIG_COMPAT
 539         BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm));
 540         BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80);
 541         BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104);
 542         BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104);
 543 #endif
 544
 545         /* Do sanity checks on page table constants */
 546         BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t));
 547         BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t));
 548         BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t));
 549         BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD
 550                         > BITS_PER_LONG);
 551 #if CONFIG_PGTABLE_LEVELS == 3
 552         BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PMD);
 553 #else
 554         BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PGD);
 555 #endif
 556
 557 #ifdef CONFIG_64BIT
 558         /* avoid ldil_%L() asm statements to sign-extend into upper 32-bits */
 559         BUILD_BUG_ON(__PAGE_OFFSET >= 0x80000000);
 560         BUILD_BUG_ON(TMPALIAS_MAP_START >= 0x80000000);
 561 #endif
 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 #if 0
 577         /*
 578          * Do not expose the virtual kernel memory layout to userspace.
 579          * But keep code for debugging purposes.
 580          */
 581         printk("virtual kernel memory layout:\n"
 582                "     vmalloc : 0x%px - 0x%px   (%4ld MB)\n"
 583                "     fixmap  : 0x%px - 0x%px   (%4ld kB)\n"
 584                "     memory  : 0x%px - 0x%px   (%4ld MB)\n"
 585                "       .init : 0x%px - 0x%px   (%4ld kB)\n"
 586                "       .data : 0x%px - 0x%px   (%4ld kB)\n"
 587                "       .text : 0x%px - 0x%px   (%4ld kB)\n",
 588
 589                (void*)VMALLOC_START, (void*)VMALLOC_END,
 590                (VMALLOC_END - VMALLOC_START) >> 20,
 591
 592                (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE),
 593                (unsigned long)(FIXMAP_SIZE / 1024),
 594
 595                __va(0), high_memory,
 596                ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
 597
 598                __init_begin, __init_end,
 599                ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10,
 600
 601                _etext, _edata,
 602                ((unsigned long)_edata - (unsigned long)_etext) >> 10,
 603
 604                _text, _etext,
 605                ((unsigned long)_etext - (unsigned long)_text) >> 10);
 606 #endif
 607 }
 608
 609 unsigned long *empty_zero_page __ro_after_init;
 610 EXPORT_SYMBOL(empty_zero_page);
 611
 612 /*
 613  * pagetable_init() sets up the page tables
 614  *
 615  * Note that gateway_init() places the Linux gateway page at page 0.
 616  * Since gateway pages cannot be dereferenced this has the desirable
 617  * side effect of trapping those pesky NULL-reference errors in the
 618  * kernel.
 619  */
 620 static void __init pagetable_init(void)
 621 {
 622         int range;
 623
 624         /* Map each physical memory range to its kernel vaddr */
 625
 626         for (range = 0; range < npmem_ranges; range++) {
 627                 unsigned long start_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
 633                 map_pages((unsigned long)__va(start_paddr), start_paddr,
 634                           size, PAGE_KERNEL, 0);
 635         }
 636
 637 #ifdef CONFIG_BLK_DEV_INITRD
 638         if (initrd_end && initrd_end > mem_limit) {
 639                 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
 640                 map_pages(initrd_start, __pa(initrd_start),
 641                           initrd_end - initrd_start, PAGE_KERNEL, 0);
 642         }
 643 #endif
 644
 645         empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 646         if (!empty_zero_page)
 647                 panic("zero page allocation failed.\n");
 648
 649 }
 650
 651 static void __init gateway_init(void)
 652 {
 653         unsigned long linux_gateway_page_addr;
 654         /* FIXME: This is 'const' in order to trick the compiler
 655            into not treating it as DP-relative data. */
 656         extern void * const linux_gateway_page;
 657
 658         linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
 659
 660         /*
 661          * Setup Linux Gateway page.
 662          *
 663          * The Linux gateway page will reside in kernel space (on virtual
 664          * page 0), so it doesn't need to be aliased into user space.
 665          */
 666
 667         map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
 668                   PAGE_SIZE, PAGE_GATEWAY, 1);
 669 }
 670
 671 static void __init fixmap_init(void)
 672 {
 673         unsigned long addr = FIXMAP_START;
 674         unsigned long end = FIXMAP_START + FIXMAP_SIZE;
 675         pgd_t *pgd = pgd_offset_k(addr);
 676         p4d_t *p4d = p4d_offset(pgd, addr);
 677         pud_t *pud = pud_offset(p4d, addr);
 678         pmd_t *pmd;
 679
 680         BUILD_BUG_ON(FIXMAP_SIZE > PMD_SIZE);
 681
 682 #if CONFIG_PGTABLE_LEVELS == 3
 683         if (pud_none(*pud)) {
 684                 pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER,
 685                                      PAGE_SIZE << PMD_TABLE_ORDER);
 686                 if (!pmd)
 687                         panic("fixmap: pmd allocation failed.\n");
 688                 pud_populate(NULL, pud, pmd);
 689         }
 690 #endif
 691
 692         pmd = pmd_offset(pud, addr);
 693         do {
 694                 pte_t *pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 695                 if (!pte)
 696                         panic("fixmap: pte allocation failed.\n");
 697
 698                 pmd_populate_kernel(&init_mm, pmd, pte);
 699
 700                 addr += PAGE_SIZE;
 701         } while (addr < end);
 702 }
 703
 704 static void __init parisc_bootmem_free(void)
 705 {
 706         unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
 707
 708         max_zone_pfn[0] = memblock_end_of_DRAM();
 709
 710         free_area_init(max_zone_pfn);
 711 }
 712
 713 void __init paging_init(void)
 714 {
 715         setup_bootmem();
 716         pagetable_init();
 717         gateway_init();
 718         fixmap_init();
 719         flush_cache_all_local(); /* start with known state */
 720         flush_tlb_all_local(NULL);
 721
 722         sparse_init();
 723         parisc_bootmem_free();
 724 }
 725
 726 static void alloc_btlb(unsigned long start, unsigned long end, int *slot,
 727                         unsigned long entry_info)
 728 {
 729         const int slot_max = btlb_info.fixed_range_info.num_comb;
 730         int min_num_pages = btlb_info.min_size;
 731         unsigned long size;
 732
 733         /* map at minimum 4 pages */
 734         if (min_num_pages < 4)
 735                 min_num_pages = 4;
 736
 737         size = HUGEPAGE_SIZE;
 738         while (start < end && *slot < slot_max && size >= PAGE_SIZE) {
 739                 /* starting address must have same alignment as size! */
 740                 /* if correctly aligned and fits in double size, increase */
 741                 if (((start & (2 * size - 1)) == 0) &&
 742                     (end - start) >= (2 * size)) {
 743                         size <<= 1;
 744                         continue;
 745                 }
 746                 /* if current size alignment is too big, try smaller size */
 747                 if ((start & (size - 1)) != 0) {
 748                         size >>= 1;
 749                         continue;
 750                 }
 751                 if ((end - start) >= size) {
 752                         if ((size >> PAGE_SHIFT) >= min_num_pages)
 753                                 pdc_btlb_insert(start >> PAGE_SHIFT, __pa(start) >> PAGE_SHIFT,
 754                                         size >> PAGE_SHIFT, entry_info, *slot);
 755                         (*slot)++;
 756                         start += size;
 757                         continue;
 758                 }
 759                 size /= 2;
 760                 continue;
 761         }
 762 }
 763
 764 void btlb_init_per_cpu(void)
 765 {
 766         unsigned long s, t, e;
 767         int slot;
 768
 769         /* BTLBs are not available on 64-bit CPUs */
 770         if (IS_ENABLED(CONFIG_PA20))
 771                 return;
 772         else if (pdc_btlb_info(&btlb_info) < 0) {
 773                 memset(&btlb_info, 0, sizeof btlb_info);
 774         }
 775
 776         /* insert BLTLBs for code and data segments */
 777         s = (uintptr_t) dereference_function_descriptor(&_stext);
 778         e = (uintptr_t) dereference_function_descriptor(&_etext);
 779         t = (uintptr_t) dereference_function_descriptor(&_sdata);
 780         BUG_ON(t != e);
 781
 782         /* code segments */
 783         slot = 0;
 784         alloc_btlb(s, e, &slot, 0x13800000);
 785
 786         /* sanity check */
 787         t = (uintptr_t) dereference_function_descriptor(&_edata);
 788         e = (uintptr_t) dereference_function_descriptor(&__bss_start);
 789         BUG_ON(t != e);
 790
 791         /* data segments */
 792         s = (uintptr_t) dereference_function_descriptor(&_sdata);
 793         e = (uintptr_t) dereference_function_descriptor(&__bss_stop);
 794         alloc_btlb(s, e, &slot, 0x11800000);
 795 }
 796
 797 #ifdef CONFIG_PA20
 798
 799 /*
 800  * Currently, all PA20 chips have 18 bit protection IDs, which is the
 801  * limiting factor (space ids are 32 bits).
 802  */
 803
 804 #define NR_SPACE_IDS 262144
 805
 806 #else
 807
 808 /*
 809  * Currently we have a one-to-one relationship between space IDs and
 810  * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
 811  * support 15 bit protection IDs, so that is the limiting factor.
 812  * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's
 813  * probably not worth the effort for a special case here.
 814  */
 815
 816 #define NR_SPACE_IDS 32768
 817
 818 #endif  /* !CONFIG_PA20 */
 819
 820 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
 821 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
 822
 823 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
 824 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
 825 static unsigned long space_id_index;
 826 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
 827 static unsigned long dirty_space_ids;
 828
 829 static DEFINE_SPINLOCK(sid_lock);
 830
 831 unsigned long alloc_sid(void)
 832 {
 833         unsigned long index;
 834
 835         spin_lock(&sid_lock);
 836
 837         if (free_space_ids == 0) {
 838                 if (dirty_space_ids != 0) {
 839                         spin_unlock(&sid_lock);
 840                         flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
 841                         spin_lock(&sid_lock);
 842                 }
 843                 BUG_ON(free_space_ids == 0);
 844         }
 845
 846         free_space_ids--;
 847
 848         index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
 849         space_id[BIT_WORD(index)] |= BIT_MASK(index);
 850         space_id_index = index;
 851
 852         spin_unlock(&sid_lock);
 853
 854         return index << SPACEID_SHIFT;
 855 }
 856
 857 void free_sid(unsigned long spaceid)
 858 {
 859         unsigned long index = spaceid >> SPACEID_SHIFT;
 860         unsigned long *dirty_space_offset, mask;
 861
 862         dirty_space_offset = &dirty_space_id[BIT_WORD(index)];
 863         mask = BIT_MASK(index);
 864
 865         spin_lock(&sid_lock);
 866
 867         BUG_ON(*dirty_space_offset & mask); /* attempt to free space id twice */
 868
 869         *dirty_space_offset |= mask;
 870         dirty_space_ids++;
 871
 872         spin_unlock(&sid_lock);
 873 }
 874
 875
 876 #ifdef CONFIG_SMP
 877 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
 878 {
 879         int i;
 880
 881         /* NOTE: sid_lock must be held upon entry */
 882
 883         *ndirtyptr = dirty_space_ids;
 884         if (dirty_space_ids != 0) {
 885             for (i = 0; i < SID_ARRAY_SIZE; i++) {
 886                 dirty_array[i] = dirty_space_id[i];
 887                 dirty_space_id[i] = 0;
 888             }
 889             dirty_space_ids = 0;
 890         }
 891
 892         return;
 893 }
 894
 895 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
 896 {
 897         int i;
 898
 899         /* NOTE: sid_lock must be held upon entry */
 900
 901         if (ndirty != 0) {
 902                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
 903                         space_id[i] ^= dirty_array[i];
 904                 }
 905
 906                 free_space_ids += ndirty;
 907                 space_id_index = 0;
 908         }
 909 }
 910
 911 #else /* CONFIG_SMP */
 912
 913 static void recycle_sids(void)
 914 {
 915         int i;
 916
 917         /* NOTE: sid_lock must be held upon entry */
 918
 919         if (dirty_space_ids != 0) {
 920                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
 921                         space_id[i] ^= dirty_space_id[i];
 922                         dirty_space_id[i] = 0;
 923                 }
 924
 925                 free_space_ids += dirty_space_ids;
 926                 dirty_space_ids = 0;
 927                 space_id_index = 0;
 928         }
 929 }
 930 #endif
 931
 932 /*
 933  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
 934  * purged, we can safely reuse the space ids that were released but
 935  * not flushed from the tlb.
 936  */
 937
 938 #ifdef CONFIG_SMP
 939
 940 static unsigned long recycle_ndirty;
 941 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
 942 static unsigned int recycle_inuse;
 943
 944 void flush_tlb_all(void)
 945 {
 946         int do_recycle;
 947
 948         do_recycle = 0;
 949         spin_lock(&sid_lock);
 950         __inc_irq_stat(irq_tlb_count);
 951         if (dirty_space_ids > RECYCLE_THRESHOLD) {
 952             BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
 953             get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
 954             recycle_inuse++;
 955             do_recycle++;
 956         }
 957         spin_unlock(&sid_lock);
 958         on_each_cpu(flush_tlb_all_local, NULL, 1);
 959         if (do_recycle) {
 960             spin_lock(&sid_lock);
 961             recycle_sids(recycle_ndirty,recycle_dirty_array);
 962             recycle_inuse = 0;
 963             spin_unlock(&sid_lock);
 964         }
 965 }
 966 #else
 967 void flush_tlb_all(void)
 968 {
 969         spin_lock(&sid_lock);
 970         __inc_irq_stat(irq_tlb_count);
 971         flush_tlb_all_local(NULL);
 972         recycle_sids();
 973         spin_unlock(&sid_lock);
 974 }
 975 #endif
 976
 977 static const pgprot_t protection_map[16] = {
 978         [VM_NONE]                                       = PAGE_NONE,
 979         [VM_READ]                                       = PAGE_READONLY,
 980         [VM_WRITE]                                      = PAGE_NONE,
 981         [VM_WRITE | VM_READ]                            = PAGE_READONLY,
 982         [VM_EXEC]                                       = PAGE_EXECREAD,
 983         [VM_EXEC | VM_READ]                             = PAGE_EXECREAD,
 984         [VM_EXEC | VM_WRITE]                            = PAGE_EXECREAD,
 985         [VM_EXEC | VM_WRITE | VM_READ]                  = PAGE_EXECREAD,
 986         [VM_SHARED]                                     = PAGE_NONE,
 987         [VM_SHARED | VM_READ]                           = PAGE_READONLY,
 988         [VM_SHARED | VM_WRITE]                          = PAGE_WRITEONLY,
 989         [VM_SHARED | VM_WRITE | VM_READ]                = PAGE_SHARED,
 990         [VM_SHARED | VM_EXEC]                           = PAGE_EXECREAD,
 991         [VM_SHARED | VM_EXEC | VM_READ]                 = PAGE_EXECREAD,
 992         [VM_SHARED | VM_EXEC | VM_WRITE]                = PAGE_RWX,
 993         [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]      = PAGE_RWX
 994 };
 995 DECLARE_VM_GET_PAGE_PROT
 996
 997 #ifdef CONFIG_EXECMEM
 998 static struct execmem_info execmem_info __ro_after_init;
 999
1000 struct execmem_info __init *execmem_arch_setup(void)
1001 {
1002         execmem_info = (struct execmem_info){
1003                 .ranges = {
1004                         [EXECMEM_DEFAULT] = {
1005                                 .start  = VMALLOC_START,
1006                                 .end    = VMALLOC_END,
1007                                 .pgprot = PAGE_KERNEL_RWX,
1008                                 .alignment = 1,
1009                         },
1010                 },
1011         };
1012
1013         return &execmem_info;
1014 }
1015 #endif /* CONFIG_EXECMEM */