arch/riscv/mm/init.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2012 Regents of the University of California
   4  * Copyright (C) 2019 Western Digital Corporation or its affiliates.
   5  */
   6
   7 #include <linux/init.h>
   8 #include <linux/mm.h>
   9 #include <linux/memblock.h>
  10 #include <linux/initrd.h>
  11 #include <linux/swap.h>
  12 #include <linux/sizes.h>
  13 #include <linux/of_fdt.h>
  14 #include <linux/libfdt.h>
  15 #include <linux/set_memory.h>
  16
  17 #include <asm/fixmap.h>
  18 #include <asm/tlbflush.h>
  19 #include <asm/sections.h>
  20 #include <asm/soc.h>
  21 #include <asm/io.h>
  22 #include <asm/ptdump.h>
  23
  24 #include "../kernel/head.h"
  25
  26 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
  27                                                         __page_aligned_bss;
  28 EXPORT_SYMBOL(empty_zero_page);
  29
  30 extern char _start[];
  31 #define DTB_EARLY_BASE_VA      PGDIR_SIZE
  32 void *dtb_early_va __initdata;
  33 uintptr_t dtb_early_pa __initdata;
  34
  35 struct pt_alloc_ops {
  36         pte_t *(*get_pte_virt)(phys_addr_t pa);
  37         phys_addr_t (*alloc_pte)(uintptr_t va);
  38 #ifndef __PAGETABLE_PMD_FOLDED
  39         pmd_t *(*get_pmd_virt)(phys_addr_t pa);
  40         phys_addr_t (*alloc_pmd)(uintptr_t va);
  41 #endif
  42 };
  43
  44 static void __init zone_sizes_init(void)
  45 {
  46         unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
  47
  48 #ifdef CONFIG_ZONE_DMA32
  49         max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G,
  50                         (unsigned long) PFN_PHYS(max_low_pfn)));
  51 #endif
  52         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
  53
  54         free_area_init(max_zone_pfns);
  55 }
  56
  57 static void setup_zero_page(void)
  58 {
  59         memset((void *)empty_zero_page, 0, PAGE_SIZE);
  60 }
  61
  62 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
  63 static inline void print_mlk(char *name, unsigned long b, unsigned long t)
  64 {
  65         pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld kB)\n", name, b, t,
  66                   (((t) - (b)) >> 10));
  67 }
  68
  69 static inline void print_mlm(char *name, unsigned long b, unsigned long t)
  70 {
  71         pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld MB)\n", name, b, t,
  72                   (((t) - (b)) >> 20));
  73 }
  74
  75 static void print_vm_layout(void)
  76 {
  77         pr_notice("Virtual kernel memory layout:\n");
  78         print_mlk("fixmap", (unsigned long)FIXADDR_START,
  79                   (unsigned long)FIXADDR_TOP);
  80         print_mlm("pci io", (unsigned long)PCI_IO_START,
  81                   (unsigned long)PCI_IO_END);
  82         print_mlm("vmemmap", (unsigned long)VMEMMAP_START,
  83                   (unsigned long)VMEMMAP_END);
  84         print_mlm("vmalloc", (unsigned long)VMALLOC_START,
  85                   (unsigned long)VMALLOC_END);
  86         print_mlm("lowmem", (unsigned long)PAGE_OFFSET,
  87                   (unsigned long)high_memory);
  88 }
  89 #else
  90 static void print_vm_layout(void) { }
  91 #endif /* CONFIG_DEBUG_VM */
  92
  93 void __init mem_init(void)
  94 {
  95 #ifdef CONFIG_FLATMEM
  96         BUG_ON(!mem_map);
  97 #endif /* CONFIG_FLATMEM */
  98
  99         high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
 100         memblock_free_all();
 101
 102         mem_init_print_info(NULL);
 103         print_vm_layout();
 104 }
 105
 106 #ifdef CONFIG_BLK_DEV_INITRD
 107 static void __init setup_initrd(void)
 108 {
 109         phys_addr_t start;
 110         unsigned long size;
 111
 112         /* Ignore the virtul address computed during device tree parsing */
 113         initrd_start = initrd_end = 0;
 114
 115         if (!phys_initrd_size)
 116                 return;
 117         /*
 118          * Round the memory region to page boundaries as per free_initrd_mem()
 119          * This allows us to detect whether the pages overlapping the initrd
 120          * are in use, but more importantly, reserves the entire set of pages
 121          * as we don't want these pages allocated for other purposes.
 122          */
 123         start = round_down(phys_initrd_start, PAGE_SIZE);
 124         size = phys_initrd_size + (phys_initrd_start - start);
 125         size = round_up(size, PAGE_SIZE);
 126
 127         if (!memblock_is_region_memory(start, size)) {
 128                 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
 129                        (u64)start, size);
 130                 goto disable;
 131         }
 132
 133         if (memblock_is_region_reserved(start, size)) {
 134                 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
 135                        (u64)start, size);
 136                 goto disable;
 137         }
 138
 139         memblock_reserve(start, size);
 140         /* Now convert initrd to virtual addresses */
 141         initrd_start = (unsigned long)__va(phys_initrd_start);
 142         initrd_end = initrd_start + phys_initrd_size;
 143         initrd_below_start_ok = 1;
 144
 145         pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
 146                 (void *)(initrd_start), size);
 147         return;
 148 disable:
 149         pr_cont(" - disabling initrd\n");
 150         initrd_start = 0;
 151         initrd_end = 0;
 152 }
 153 #endif /* CONFIG_BLK_DEV_INITRD */
 154
 155 void __init setup_bootmem(void)
 156 {
 157         phys_addr_t mem_size = 0;
 158         phys_addr_t total_mem = 0;
 159         phys_addr_t mem_start, start, end = 0;
 160         phys_addr_t vmlinux_end = __pa_symbol(&_end);
 161         phys_addr_t vmlinux_start = __pa_symbol(&_start);
 162         u64 i;
 163
 164         /* Find the memory region containing the kernel */
 165         for_each_mem_range(i, &start, &end) {
 166                 phys_addr_t size = end - start;
 167                 if (!total_mem)
 168                         mem_start = start;
 169                 if (start <= vmlinux_start && vmlinux_end <= end)
 170                         BUG_ON(size == 0);
 171                 total_mem = total_mem + size;
 172         }
 173
 174         /*
 175          * Remove memblock from the end of usable area to the
 176          * end of region
 177          */
 178         mem_size = min(total_mem, (phys_addr_t)-PAGE_OFFSET);
 179         if (mem_start + mem_size < end)
 180                 memblock_remove(mem_start + mem_size,
 181                                 end - mem_start - mem_size);
 182
 183         /* Reserve from the start of the kernel to the end of the kernel */
 184         memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
 185
 186         max_pfn = PFN_DOWN(memblock_end_of_DRAM());
 187         max_low_pfn = max_pfn;
 188         set_max_mapnr(max_low_pfn);
 189
 190 #ifdef CONFIG_BLK_DEV_INITRD
 191         setup_initrd();
 192 #endif /* CONFIG_BLK_DEV_INITRD */
 193
 194         /*
 195          * Avoid using early_init_fdt_reserve_self() since __pa() does
 196          * not work for DTB pointers that are fixmap addresses
 197          */
 198         memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
 199
 200         early_init_fdt_scan_reserved_mem();
 201         memblock_allow_resize();
 202         memblock_dump_all();
 203 }
 204
 205 #ifdef CONFIG_MMU
 206 static struct pt_alloc_ops pt_ops;
 207
 208 unsigned long va_pa_offset;
 209 EXPORT_SYMBOL(va_pa_offset);
 210 unsigned long pfn_base;
 211 EXPORT_SYMBOL(pfn_base);
 212
 213 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 214 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 215 pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
 216
 217 #define MAX_EARLY_MAPPING_SIZE  SZ_128M
 218
 219 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
 220
 221 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
 222 {
 223         unsigned long addr = __fix_to_virt(idx);
 224         pte_t *ptep;
 225
 226         BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
 227
 228         ptep = &fixmap_pte[pte_index(addr)];
 229
 230         if (pgprot_val(prot))
 231                 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
 232         else
 233                 pte_clear(&init_mm, addr, ptep);
 234         local_flush_tlb_page(addr);
 235 }
 236
 237 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
 238 {
 239         return (pte_t *)((uintptr_t)pa);
 240 }
 241
 242 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
 243 {
 244         clear_fixmap(FIX_PTE);
 245         return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
 246 }
 247
 248 static inline pte_t *get_pte_virt_late(phys_addr_t pa)
 249 {
 250         return (pte_t *) __va(pa);
 251 }
 252
 253 static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
 254 {
 255         /*
 256          * We only create PMD or PGD early mappings so we
 257          * should never reach here with MMU disabled.
 258          */
 259         BUG();
 260 }
 261
 262 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
 263 {
 264         return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 265 }
 266
 267 static phys_addr_t alloc_pte_late(uintptr_t va)
 268 {
 269         unsigned long vaddr;
 270
 271         vaddr = __get_free_page(GFP_KERNEL);
 272         if (!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)))
 273                 BUG();
 274         return __pa(vaddr);
 275 }
 276
 277 static void __init create_pte_mapping(pte_t *ptep,
 278                                       uintptr_t va, phys_addr_t pa,
 279                                       phys_addr_t sz, pgprot_t prot)
 280 {
 281         uintptr_t pte_idx = pte_index(va);
 282
 283         BUG_ON(sz != PAGE_SIZE);
 284
 285         if (pte_none(ptep[pte_idx]))
 286                 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
 287 }
 288
 289 #ifndef __PAGETABLE_PMD_FOLDED
 290
 291 pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
 292 pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
 293
 294 #if MAX_EARLY_MAPPING_SIZE < PGDIR_SIZE
 295 #define NUM_EARLY_PMDS          1UL
 296 #else
 297 #define NUM_EARLY_PMDS          (1UL + MAX_EARLY_MAPPING_SIZE / PGDIR_SIZE)
 298 #endif
 299 pmd_t early_pmd[PTRS_PER_PMD * NUM_EARLY_PMDS] __initdata __aligned(PAGE_SIZE);
 300
 301 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
 302 {
 303         /* Before MMU is enabled */
 304         return (pmd_t *)((uintptr_t)pa);
 305 }
 306
 307 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
 308 {
 309         clear_fixmap(FIX_PMD);
 310         return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
 311 }
 312
 313 static pmd_t *get_pmd_virt_late(phys_addr_t pa)
 314 {
 315         return (pmd_t *) __va(pa);
 316 }
 317
 318 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
 319 {
 320         uintptr_t pmd_num;
 321
 322         pmd_num = (va - PAGE_OFFSET) >> PGDIR_SHIFT;
 323         BUG_ON(pmd_num >= NUM_EARLY_PMDS);
 324         return (uintptr_t)&early_pmd[pmd_num * PTRS_PER_PMD];
 325 }
 326
 327 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
 328 {
 329         return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 330 }
 331
 332 static phys_addr_t alloc_pmd_late(uintptr_t va)
 333 {
 334         unsigned long vaddr;
 335
 336         vaddr = __get_free_page(GFP_KERNEL);
 337         BUG_ON(!vaddr);
 338         return __pa(vaddr);
 339 }
 340
 341 static void __init create_pmd_mapping(pmd_t *pmdp,
 342                                       uintptr_t va, phys_addr_t pa,
 343                                       phys_addr_t sz, pgprot_t prot)
 344 {
 345         pte_t *ptep;
 346         phys_addr_t pte_phys;
 347         uintptr_t pmd_idx = pmd_index(va);
 348
 349         if (sz == PMD_SIZE) {
 350                 if (pmd_none(pmdp[pmd_idx]))
 351                         pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
 352                 return;
 353         }
 354
 355         if (pmd_none(pmdp[pmd_idx])) {
 356                 pte_phys = pt_ops.alloc_pte(va);
 357                 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
 358                 ptep = pt_ops.get_pte_virt(pte_phys);
 359                 memset(ptep, 0, PAGE_SIZE);
 360         } else {
 361                 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
 362                 ptep = pt_ops.get_pte_virt(pte_phys);
 363         }
 364
 365         create_pte_mapping(ptep, va, pa, sz, prot);
 366 }
 367
 368 #define pgd_next_t              pmd_t
 369 #define alloc_pgd_next(__va)    pt_ops.alloc_pmd(__va)
 370 #define get_pgd_next_virt(__pa) pt_ops.get_pmd_virt(__pa)
 371 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)      \
 372         create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
 373 #define fixmap_pgd_next         fixmap_pmd
 374 #else
 375 #define pgd_next_t              pte_t
 376 #define alloc_pgd_next(__va)    pt_ops.alloc_pte(__va)
 377 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
 378 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)      \
 379         create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
 380 #define fixmap_pgd_next         fixmap_pte
 381 #endif
 382
 383 void __init create_pgd_mapping(pgd_t *pgdp,
 384                                       uintptr_t va, phys_addr_t pa,
 385                                       phys_addr_t sz, pgprot_t prot)
 386 {
 387         pgd_next_t *nextp;
 388         phys_addr_t next_phys;
 389         uintptr_t pgd_idx = pgd_index(va);
 390
 391         if (sz == PGDIR_SIZE) {
 392                 if (pgd_val(pgdp[pgd_idx]) == 0)
 393                         pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
 394                 return;
 395         }
 396
 397         if (pgd_val(pgdp[pgd_idx]) == 0) {
 398                 next_phys = alloc_pgd_next(va);
 399                 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
 400                 nextp = get_pgd_next_virt(next_phys);
 401                 memset(nextp, 0, PAGE_SIZE);
 402         } else {
 403                 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
 404                 nextp = get_pgd_next_virt(next_phys);
 405         }
 406
 407         create_pgd_next_mapping(nextp, va, pa, sz, prot);
 408 }
 409
 410 static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
 411 {
 412         /* Upgrade to PMD_SIZE mappings whenever possible */
 413         if ((base & (PMD_SIZE - 1)) || (size & (PMD_SIZE - 1)))
 414                 return PAGE_SIZE;
 415
 416         return PMD_SIZE;
 417 }
 418
 419 /*
 420  * setup_vm() is called from head.S with MMU-off.
 421  *
 422  * Following requirements should be honoured for setup_vm() to work
 423  * correctly:
 424  * 1) It should use PC-relative addressing for accessing kernel symbols.
 425  *    To achieve this we always use GCC cmodel=medany.
 426  * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
 427  *    so disable compiler instrumentation when FTRACE is enabled.
 428  *
 429  * Currently, the above requirements are honoured by using custom CFLAGS
 430  * for init.o in mm/Makefile.
 431  */
 432
 433 #ifndef __riscv_cmodel_medany
 434 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
 435 #endif
 436
 437 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 438 {
 439         uintptr_t va, pa, end_va;
 440         uintptr_t load_pa = (uintptr_t)(&_start);
 441         uintptr_t load_sz = (uintptr_t)(&_end) - load_pa;
 442         uintptr_t map_size = best_map_size(load_pa, MAX_EARLY_MAPPING_SIZE);
 443 #ifndef __PAGETABLE_PMD_FOLDED
 444         pmd_t fix_bmap_spmd, fix_bmap_epmd;
 445 #endif
 446
 447         va_pa_offset = PAGE_OFFSET - load_pa;
 448         pfn_base = PFN_DOWN(load_pa);
 449
 450         /*
 451          * Enforce boot alignment requirements of RV32 and
 452          * RV64 by only allowing PMD or PGD mappings.
 453          */
 454         BUG_ON(map_size == PAGE_SIZE);
 455
 456         /* Sanity check alignment and size */
 457         BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
 458         BUG_ON((load_pa % map_size) != 0);
 459         BUG_ON(load_sz > MAX_EARLY_MAPPING_SIZE);
 460
 461         pt_ops.alloc_pte = alloc_pte_early;
 462         pt_ops.get_pte_virt = get_pte_virt_early;
 463 #ifndef __PAGETABLE_PMD_FOLDED
 464         pt_ops.alloc_pmd = alloc_pmd_early;
 465         pt_ops.get_pmd_virt = get_pmd_virt_early;
 466 #endif
 467         /* Setup early PGD for fixmap */
 468         create_pgd_mapping(early_pg_dir, FIXADDR_START,
 469                            (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
 470
 471 #ifndef __PAGETABLE_PMD_FOLDED
 472         /* Setup fixmap PMD */
 473         create_pmd_mapping(fixmap_pmd, FIXADDR_START,
 474                            (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
 475         /* Setup trampoline PGD and PMD */
 476         create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
 477                            (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
 478         create_pmd_mapping(trampoline_pmd, PAGE_OFFSET,
 479                            load_pa, PMD_SIZE, PAGE_KERNEL_EXEC);
 480 #else
 481         /* Setup trampoline PGD */
 482         create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
 483                            load_pa, PGDIR_SIZE, PAGE_KERNEL_EXEC);
 484 #endif
 485
 486         /*
 487          * Setup early PGD covering entire kernel which will allows
 488          * us to reach paging_init(). We map all memory banks later
 489          * in setup_vm_final() below.
 490          */
 491         end_va = PAGE_OFFSET + load_sz;
 492         for (va = PAGE_OFFSET; va < end_va; va += map_size)
 493                 create_pgd_mapping(early_pg_dir, va,
 494                                    load_pa + (va - PAGE_OFFSET),
 495                                    map_size, PAGE_KERNEL_EXEC);
 496
 497         /* Create two consecutive PGD mappings for FDT early scan */
 498         pa = dtb_pa & ~(PGDIR_SIZE - 1);
 499         create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
 500                            pa, PGDIR_SIZE, PAGE_KERNEL);
 501         create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA + PGDIR_SIZE,
 502                            pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL);
 503         dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE - 1));
 504         dtb_early_pa = dtb_pa;
 505
 506         /*
 507          * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
 508          * range can not span multiple pmds.
 509          */
 510         BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
 511                      != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
 512
 513 #ifndef __PAGETABLE_PMD_FOLDED
 514         /*
 515          * Early ioremap fixmap is already created as it lies within first 2MB
 516          * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
 517          * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
 518          * the user if not.
 519          */
 520         fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
 521         fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
 522         if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
 523                 WARN_ON(1);
 524                 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
 525                         pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
 526                 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
 527                         fix_to_virt(FIX_BTMAP_BEGIN));
 528                 pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
 529                         fix_to_virt(FIX_BTMAP_END));
 530
 531                 pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
 532                 pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
 533         }
 534 #endif
 535 }
 536
 537 static void __init setup_vm_final(void)
 538 {
 539         uintptr_t va, map_size;
 540         phys_addr_t pa, start, end;
 541         u64 i;
 542
 543         /**
 544          * MMU is enabled at this point. But page table setup is not complete yet.
 545          * fixmap page table alloc functions should be used at this point
 546          */
 547         pt_ops.alloc_pte = alloc_pte_fixmap;
 548         pt_ops.get_pte_virt = get_pte_virt_fixmap;
 549 #ifndef __PAGETABLE_PMD_FOLDED
 550         pt_ops.alloc_pmd = alloc_pmd_fixmap;
 551         pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
 552 #endif
 553         /* Setup swapper PGD for fixmap */
 554         create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
 555                            __pa_symbol(fixmap_pgd_next),
 556                            PGDIR_SIZE, PAGE_TABLE);
 557
 558         /* Map all memory banks */
 559         for_each_mem_range(i, &start, &end) {
 560                 if (start >= end)
 561                         break;
 562                 if (start <= __pa(PAGE_OFFSET) &&
 563                     __pa(PAGE_OFFSET) < end)
 564                         start = __pa(PAGE_OFFSET);
 565
 566                 map_size = best_map_size(start, end - start);
 567                 for (pa = start; pa < end; pa += map_size) {
 568                         va = (uintptr_t)__va(pa);
 569                         create_pgd_mapping(swapper_pg_dir, va, pa,
 570                                            map_size, PAGE_KERNEL_EXEC);
 571                 }
 572         }
 573
 574         /* Clear fixmap PTE and PMD mappings */
 575         clear_fixmap(FIX_PTE);
 576         clear_fixmap(FIX_PMD);
 577
 578         /* Move to swapper page table */
 579         csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
 580         local_flush_tlb_all();
 581
 582         /* generic page allocation functions must be used to setup page table */
 583         pt_ops.alloc_pte = alloc_pte_late;
 584         pt_ops.get_pte_virt = get_pte_virt_late;
 585 #ifndef __PAGETABLE_PMD_FOLDED
 586         pt_ops.alloc_pmd = alloc_pmd_late;
 587         pt_ops.get_pmd_virt = get_pmd_virt_late;
 588 #endif
 589 }
 590 #else
 591 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 592 {
 593 #ifdef CONFIG_BUILTIN_DTB
 594         dtb_early_va = soc_lookup_builtin_dtb();
 595         if (!dtb_early_va) {
 596                 /* Fallback to first available DTS */
 597                 dtb_early_va = (void *) __dtb_start;
 598         }
 599 #else
 600         dtb_early_va = (void *)dtb_pa;
 601 #endif
 602         dtb_early_pa = dtb_pa;
 603 }
 604
 605 static inline void setup_vm_final(void)
 606 {
 607 }
 608 #endif /* CONFIG_MMU */
 609
 610 #ifdef CONFIG_STRICT_KERNEL_RWX
 611 void mark_rodata_ro(void)
 612 {
 613         unsigned long text_start = (unsigned long)_text;
 614         unsigned long text_end = (unsigned long)_etext;
 615         unsigned long rodata_start = (unsigned long)__start_rodata;
 616         unsigned long data_start = (unsigned long)_data;
 617         unsigned long max_low = (unsigned long)(__va(PFN_PHYS(max_low_pfn)));
 618
 619         set_memory_ro(text_start, (text_end - text_start) >> PAGE_SHIFT);
 620         set_memory_ro(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
 621         set_memory_nx(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
 622         set_memory_nx(data_start, (max_low - data_start) >> PAGE_SHIFT);
 623
 624         debug_checkwx();
 625 }
 626 #endif
 627
 628 static void __init resource_init(void)
 629 {
 630         struct memblock_region *region;
 631
 632         for_each_mem_region(region) {
 633                 struct resource *res;
 634
 635                 res = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
 636                 if (!res)
 637                         panic("%s: Failed to allocate %zu bytes\n", __func__,
 638                               sizeof(struct resource));
 639
 640                 if (memblock_is_nomap(region)) {
 641                         res->name = "reserved";
 642                         res->flags = IORESOURCE_MEM;
 643                 } else {
 644                         res->name = "System RAM";
 645                         res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 646                 }
 647                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 648                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 649
 650                 request_resource(&iomem_resource, res);
 651         }
 652 }
 653
 654 void __init paging_init(void)
 655 {
 656         setup_vm_final();
 657         sparse_init();
 658         setup_zero_page();
 659         zone_sizes_init();
 660         resource_init();
 661 }
 662
 663 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 664 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 665                                struct vmem_altmap *altmap)
 666 {
 667         return vmemmap_populate_basepages(start, end, node, NULL);
 668 }
 669 #endif