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_start = 0;
 158         phys_addr_t start, end = 0;
 159         phys_addr_t vmlinux_end = __pa_symbol(&_end);
 160         phys_addr_t vmlinux_start = __pa_symbol(&_start);
 161         u64 i;
 162
 163         /* Find the memory region containing the kernel */
 164         for_each_mem_range(i, &start, &end) {
 165                 phys_addr_t size = end - start;
 166                 if (!mem_start)
 167                         mem_start = start;
 168                 if (start <= vmlinux_start && vmlinux_end <= end)
 169                         BUG_ON(size == 0);
 170         }
 171
 172         /*
 173          * The maximal physical memory size is -PAGE_OFFSET.
 174          * Make sure that any memory beyond mem_start + (-PAGE_OFFSET) is removed
 175          * as it is unusable by kernel.
 176          */
 177         memblock_enforce_memory_limit(mem_start - PAGE_OFFSET);
 178
 179         /* Reserve from the start of the kernel to the end of the kernel */
 180         memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
 181
 182         max_pfn = PFN_DOWN(memblock_end_of_DRAM());
 183         max_low_pfn = max_pfn;
 184         set_max_mapnr(max_low_pfn);
 185
 186 #ifdef CONFIG_BLK_DEV_INITRD
 187         setup_initrd();
 188 #endif /* CONFIG_BLK_DEV_INITRD */
 189
 190         /*
 191          * Avoid using early_init_fdt_reserve_self() since __pa() does
 192          * not work for DTB pointers that are fixmap addresses
 193          */
 194         memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
 195
 196         early_init_fdt_scan_reserved_mem();
 197         memblock_allow_resize();
 198         memblock_dump_all();
 199 }
 200
 201 #ifdef CONFIG_MMU
 202 static struct pt_alloc_ops pt_ops;
 203
 204 unsigned long va_pa_offset;
 205 EXPORT_SYMBOL(va_pa_offset);
 206 unsigned long pfn_base;
 207 EXPORT_SYMBOL(pfn_base);
 208
 209 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 210 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 211 pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
 212
 213 #define MAX_EARLY_MAPPING_SIZE  SZ_128M
 214
 215 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
 216
 217 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
 218 {
 219         unsigned long addr = __fix_to_virt(idx);
 220         pte_t *ptep;
 221
 222         BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
 223
 224         ptep = &fixmap_pte[pte_index(addr)];
 225
 226         if (pgprot_val(prot))
 227                 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
 228         else
 229                 pte_clear(&init_mm, addr, ptep);
 230         local_flush_tlb_page(addr);
 231 }
 232
 233 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
 234 {
 235         return (pte_t *)((uintptr_t)pa);
 236 }
 237
 238 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
 239 {
 240         clear_fixmap(FIX_PTE);
 241         return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
 242 }
 243
 244 static inline pte_t *get_pte_virt_late(phys_addr_t pa)
 245 {
 246         return (pte_t *) __va(pa);
 247 }
 248
 249 static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
 250 {
 251         /*
 252          * We only create PMD or PGD early mappings so we
 253          * should never reach here with MMU disabled.
 254          */
 255         BUG();
 256 }
 257
 258 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
 259 {
 260         return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 261 }
 262
 263 static phys_addr_t alloc_pte_late(uintptr_t va)
 264 {
 265         unsigned long vaddr;
 266
 267         vaddr = __get_free_page(GFP_KERNEL);
 268         if (!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)))
 269                 BUG();
 270         return __pa(vaddr);
 271 }
 272
 273 static void __init create_pte_mapping(pte_t *ptep,
 274                                       uintptr_t va, phys_addr_t pa,
 275                                       phys_addr_t sz, pgprot_t prot)
 276 {
 277         uintptr_t pte_idx = pte_index(va);
 278
 279         BUG_ON(sz != PAGE_SIZE);
 280
 281         if (pte_none(ptep[pte_idx]))
 282                 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
 283 }
 284
 285 #ifndef __PAGETABLE_PMD_FOLDED
 286
 287 pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
 288 pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
 289
 290 #if MAX_EARLY_MAPPING_SIZE < PGDIR_SIZE
 291 #define NUM_EARLY_PMDS          1UL
 292 #else
 293 #define NUM_EARLY_PMDS          (1UL + MAX_EARLY_MAPPING_SIZE / PGDIR_SIZE)
 294 #endif
 295 pmd_t early_pmd[PTRS_PER_PMD * NUM_EARLY_PMDS] __initdata __aligned(PAGE_SIZE);
 296
 297 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
 298 {
 299         /* Before MMU is enabled */
 300         return (pmd_t *)((uintptr_t)pa);
 301 }
 302
 303 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
 304 {
 305         clear_fixmap(FIX_PMD);
 306         return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
 307 }
 308
 309 static pmd_t *get_pmd_virt_late(phys_addr_t pa)
 310 {
 311         return (pmd_t *) __va(pa);
 312 }
 313
 314 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
 315 {
 316         uintptr_t pmd_num;
 317
 318         pmd_num = (va - PAGE_OFFSET) >> PGDIR_SHIFT;
 319         BUG_ON(pmd_num >= NUM_EARLY_PMDS);
 320         return (uintptr_t)&early_pmd[pmd_num * PTRS_PER_PMD];
 321 }
 322
 323 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
 324 {
 325         return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 326 }
 327
 328 static phys_addr_t alloc_pmd_late(uintptr_t va)
 329 {
 330         unsigned long vaddr;
 331
 332         vaddr = __get_free_page(GFP_KERNEL);
 333         BUG_ON(!vaddr);
 334         return __pa(vaddr);
 335 }
 336
 337 static void __init create_pmd_mapping(pmd_t *pmdp,
 338                                       uintptr_t va, phys_addr_t pa,
 339                                       phys_addr_t sz, pgprot_t prot)
 340 {
 341         pte_t *ptep;
 342         phys_addr_t pte_phys;
 343         uintptr_t pmd_idx = pmd_index(va);
 344
 345         if (sz == PMD_SIZE) {
 346                 if (pmd_none(pmdp[pmd_idx]))
 347                         pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
 348                 return;
 349         }
 350
 351         if (pmd_none(pmdp[pmd_idx])) {
 352                 pte_phys = pt_ops.alloc_pte(va);
 353                 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
 354                 ptep = pt_ops.get_pte_virt(pte_phys);
 355                 memset(ptep, 0, PAGE_SIZE);
 356         } else {
 357                 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
 358                 ptep = pt_ops.get_pte_virt(pte_phys);
 359         }
 360
 361         create_pte_mapping(ptep, va, pa, sz, prot);
 362 }
 363
 364 #define pgd_next_t              pmd_t
 365 #define alloc_pgd_next(__va)    pt_ops.alloc_pmd(__va)
 366 #define get_pgd_next_virt(__pa) pt_ops.get_pmd_virt(__pa)
 367 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)      \
 368         create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
 369 #define fixmap_pgd_next         fixmap_pmd
 370 #else
 371 #define pgd_next_t              pte_t
 372 #define alloc_pgd_next(__va)    pt_ops.alloc_pte(__va)
 373 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
 374 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)      \
 375         create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
 376 #define fixmap_pgd_next         fixmap_pte
 377 #endif
 378
 379 void __init create_pgd_mapping(pgd_t *pgdp,
 380                                       uintptr_t va, phys_addr_t pa,
 381                                       phys_addr_t sz, pgprot_t prot)
 382 {
 383         pgd_next_t *nextp;
 384         phys_addr_t next_phys;
 385         uintptr_t pgd_idx = pgd_index(va);
 386
 387         if (sz == PGDIR_SIZE) {
 388                 if (pgd_val(pgdp[pgd_idx]) == 0)
 389                         pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
 390                 return;
 391         }
 392
 393         if (pgd_val(pgdp[pgd_idx]) == 0) {
 394                 next_phys = alloc_pgd_next(va);
 395                 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
 396                 nextp = get_pgd_next_virt(next_phys);
 397                 memset(nextp, 0, PAGE_SIZE);
 398         } else {
 399                 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
 400                 nextp = get_pgd_next_virt(next_phys);
 401         }
 402
 403         create_pgd_next_mapping(nextp, va, pa, sz, prot);
 404 }
 405
 406 static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
 407 {
 408         /* Upgrade to PMD_SIZE mappings whenever possible */
 409         if ((base & (PMD_SIZE - 1)) || (size & (PMD_SIZE - 1)))
 410                 return PAGE_SIZE;
 411
 412         return PMD_SIZE;
 413 }
 414
 415 /*
 416  * setup_vm() is called from head.S with MMU-off.
 417  *
 418  * Following requirements should be honoured for setup_vm() to work
 419  * correctly:
 420  * 1) It should use PC-relative addressing for accessing kernel symbols.
 421  *    To achieve this we always use GCC cmodel=medany.
 422  * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
 423  *    so disable compiler instrumentation when FTRACE is enabled.
 424  *
 425  * Currently, the above requirements are honoured by using custom CFLAGS
 426  * for init.o in mm/Makefile.
 427  */
 428
 429 #ifndef __riscv_cmodel_medany
 430 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
 431 #endif
 432
 433 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 434 {
 435         uintptr_t va, pa, end_va;
 436         uintptr_t load_pa = (uintptr_t)(&_start);
 437         uintptr_t load_sz = (uintptr_t)(&_end) - load_pa;
 438         uintptr_t map_size = best_map_size(load_pa, MAX_EARLY_MAPPING_SIZE);
 439 #ifndef __PAGETABLE_PMD_FOLDED
 440         pmd_t fix_bmap_spmd, fix_bmap_epmd;
 441 #endif
 442
 443         va_pa_offset = PAGE_OFFSET - load_pa;
 444         pfn_base = PFN_DOWN(load_pa);
 445
 446         /*
 447          * Enforce boot alignment requirements of RV32 and
 448          * RV64 by only allowing PMD or PGD mappings.
 449          */
 450         BUG_ON(map_size == PAGE_SIZE);
 451
 452         /* Sanity check alignment and size */
 453         BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
 454         BUG_ON((load_pa % map_size) != 0);
 455         BUG_ON(load_sz > MAX_EARLY_MAPPING_SIZE);
 456
 457         pt_ops.alloc_pte = alloc_pte_early;
 458         pt_ops.get_pte_virt = get_pte_virt_early;
 459 #ifndef __PAGETABLE_PMD_FOLDED
 460         pt_ops.alloc_pmd = alloc_pmd_early;
 461         pt_ops.get_pmd_virt = get_pmd_virt_early;
 462 #endif
 463         /* Setup early PGD for fixmap */
 464         create_pgd_mapping(early_pg_dir, FIXADDR_START,
 465                            (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
 466
 467 #ifndef __PAGETABLE_PMD_FOLDED
 468         /* Setup fixmap PMD */
 469         create_pmd_mapping(fixmap_pmd, FIXADDR_START,
 470                            (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
 471         /* Setup trampoline PGD and PMD */
 472         create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
 473                            (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
 474         create_pmd_mapping(trampoline_pmd, PAGE_OFFSET,
 475                            load_pa, PMD_SIZE, PAGE_KERNEL_EXEC);
 476 #else
 477         /* Setup trampoline PGD */
 478         create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
 479                            load_pa, PGDIR_SIZE, PAGE_KERNEL_EXEC);
 480 #endif
 481
 482         /*
 483          * Setup early PGD covering entire kernel which will allows
 484          * us to reach paging_init(). We map all memory banks later
 485          * in setup_vm_final() below.
 486          */
 487         end_va = PAGE_OFFSET + load_sz;
 488         for (va = PAGE_OFFSET; va < end_va; va += map_size)
 489                 create_pgd_mapping(early_pg_dir, va,
 490                                    load_pa + (va - PAGE_OFFSET),
 491                                    map_size, PAGE_KERNEL_EXEC);
 492
 493         /* Create two consecutive PGD mappings for FDT early scan */
 494         pa = dtb_pa & ~(PGDIR_SIZE - 1);
 495         create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
 496                            pa, PGDIR_SIZE, PAGE_KERNEL);
 497         create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA + PGDIR_SIZE,
 498                            pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL);
 499         dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE - 1));
 500         dtb_early_pa = dtb_pa;
 501
 502         /*
 503          * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
 504          * range can not span multiple pmds.
 505          */
 506         BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
 507                      != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
 508
 509 #ifndef __PAGETABLE_PMD_FOLDED
 510         /*
 511          * Early ioremap fixmap is already created as it lies within first 2MB
 512          * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
 513          * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
 514          * the user if not.
 515          */
 516         fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
 517         fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
 518         if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
 519                 WARN_ON(1);
 520                 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
 521                         pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
 522                 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
 523                         fix_to_virt(FIX_BTMAP_BEGIN));
 524                 pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
 525                         fix_to_virt(FIX_BTMAP_END));
 526
 527                 pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
 528                 pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
 529         }
 530 #endif
 531 }
 532
 533 static void __init setup_vm_final(void)
 534 {
 535         uintptr_t va, map_size;
 536         phys_addr_t pa, start, end;
 537         u64 i;
 538
 539         /**
 540          * MMU is enabled at this point. But page table setup is not complete yet.
 541          * fixmap page table alloc functions should be used at this point
 542          */
 543         pt_ops.alloc_pte = alloc_pte_fixmap;
 544         pt_ops.get_pte_virt = get_pte_virt_fixmap;
 545 #ifndef __PAGETABLE_PMD_FOLDED
 546         pt_ops.alloc_pmd = alloc_pmd_fixmap;
 547         pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
 548 #endif
 549         /* Setup swapper PGD for fixmap */
 550         create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
 551                            __pa_symbol(fixmap_pgd_next),
 552                            PGDIR_SIZE, PAGE_TABLE);
 553
 554         /* Map all memory banks */
 555         for_each_mem_range(i, &start, &end) {
 556                 if (start >= end)
 557                         break;
 558                 if (start <= __pa(PAGE_OFFSET) &&
 559                     __pa(PAGE_OFFSET) < end)
 560                         start = __pa(PAGE_OFFSET);
 561
 562                 map_size = best_map_size(start, end - start);
 563                 for (pa = start; pa < end; pa += map_size) {
 564                         va = (uintptr_t)__va(pa);
 565                         create_pgd_mapping(swapper_pg_dir, va, pa,
 566                                            map_size, PAGE_KERNEL_EXEC);
 567                 }
 568         }
 569
 570         /* Clear fixmap PTE and PMD mappings */
 571         clear_fixmap(FIX_PTE);
 572         clear_fixmap(FIX_PMD);
 573
 574         /* Move to swapper page table */
 575         csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
 576         local_flush_tlb_all();
 577
 578         /* generic page allocation functions must be used to setup page table */
 579         pt_ops.alloc_pte = alloc_pte_late;
 580         pt_ops.get_pte_virt = get_pte_virt_late;
 581 #ifndef __PAGETABLE_PMD_FOLDED
 582         pt_ops.alloc_pmd = alloc_pmd_late;
 583         pt_ops.get_pmd_virt = get_pmd_virt_late;
 584 #endif
 585 }
 586 #else
 587 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 588 {
 589 #ifdef CONFIG_BUILTIN_DTB
 590         dtb_early_va = soc_lookup_builtin_dtb();
 591         if (!dtb_early_va) {
 592                 /* Fallback to first available DTS */
 593                 dtb_early_va = (void *) __dtb_start;
 594         }
 595 #else
 596         dtb_early_va = (void *)dtb_pa;
 597 #endif
 598         dtb_early_pa = dtb_pa;
 599 }
 600
 601 static inline void setup_vm_final(void)
 602 {
 603 }
 604 #endif /* CONFIG_MMU */
 605
 606 #ifdef CONFIG_STRICT_KERNEL_RWX
 607 void mark_rodata_ro(void)
 608 {
 609         unsigned long text_start = (unsigned long)_text;
 610         unsigned long text_end = (unsigned long)_etext;
 611         unsigned long rodata_start = (unsigned long)__start_rodata;
 612         unsigned long data_start = (unsigned long)_data;
 613         unsigned long max_low = (unsigned long)(__va(PFN_PHYS(max_low_pfn)));
 614
 615         set_memory_ro(text_start, (text_end - text_start) >> PAGE_SHIFT);
 616         set_memory_ro(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
 617         set_memory_nx(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
 618         set_memory_nx(data_start, (max_low - data_start) >> PAGE_SHIFT);
 619
 620         debug_checkwx();
 621 }
 622 #endif
 623
 624 static void __init resource_init(void)
 625 {
 626         struct memblock_region *region;
 627
 628         for_each_mem_region(region) {
 629                 struct resource *res;
 630
 631                 res = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
 632                 if (!res)
 633                         panic("%s: Failed to allocate %zu bytes\n", __func__,
 634                               sizeof(struct resource));
 635
 636                 if (memblock_is_nomap(region)) {
 637                         res->name = "reserved";
 638                         res->flags = IORESOURCE_MEM;
 639                 } else {
 640                         res->name = "System RAM";
 641                         res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 642                 }
 643                 res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 644                 res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 645
 646                 request_resource(&iomem_resource, res);
 647         }
 648 }
 649
 650 void __init paging_init(void)
 651 {
 652         setup_vm_final();
 653         sparse_init();
 654         setup_zero_page();
 655         zone_sizes_init();
 656         resource_init();
 657 }
 658
 659 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 660 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
 661                                struct vmem_altmap *altmap)
 662 {
 663         return vmemmap_populate_basepages(start, end, node, NULL);
 664 }
 665 #endif