1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2012 Regents of the University of California
4 * Copyright (C) 2019 Western Digital Corporation or its affiliates.
7 #include <linux/init.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 #include <linux/dma-map-ops.h>
18 #include <asm/fixmap.h>
19 #include <asm/tlbflush.h>
20 #include <asm/sections.h>
23 #include <asm/ptdump.h>
26 #include "../kernel/head.h"
28 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
30 EXPORT_SYMBOL(empty_zero_page);
33 #define DTB_EARLY_BASE_VA PGDIR_SIZE
34 void *dtb_early_va __initdata;
35 uintptr_t dtb_early_pa __initdata;
38 pte_t *(*get_pte_virt)(phys_addr_t pa);
39 phys_addr_t (*alloc_pte)(uintptr_t va);
40 #ifndef __PAGETABLE_PMD_FOLDED
41 pmd_t *(*get_pmd_virt)(phys_addr_t pa);
42 phys_addr_t (*alloc_pmd)(uintptr_t va);
46 static phys_addr_t dma32_phys_limit __ro_after_init;
48 static void __init zone_sizes_init(void)
50 unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
52 #ifdef CONFIG_ZONE_DMA32
53 max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
55 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
57 free_area_init(max_zone_pfns);
60 static void setup_zero_page(void)
62 memset((void *)empty_zero_page, 0, PAGE_SIZE);
65 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
66 static inline void print_mlk(char *name, unsigned long b, unsigned long t)
68 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t,
72 static inline void print_mlm(char *name, unsigned long b, unsigned long t)
74 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t,
78 static void print_vm_layout(void)
80 pr_notice("Virtual kernel memory layout:\n");
81 print_mlk("fixmap", (unsigned long)FIXADDR_START,
82 (unsigned long)FIXADDR_TOP);
83 print_mlm("pci io", (unsigned long)PCI_IO_START,
84 (unsigned long)PCI_IO_END);
85 print_mlm("vmemmap", (unsigned long)VMEMMAP_START,
86 (unsigned long)VMEMMAP_END);
87 print_mlm("vmalloc", (unsigned long)VMALLOC_START,
88 (unsigned long)VMALLOC_END);
89 print_mlm("lowmem", (unsigned long)PAGE_OFFSET,
90 (unsigned long)high_memory);
93 static void print_vm_layout(void) { }
94 #endif /* CONFIG_DEBUG_VM */
96 void __init mem_init(void)
100 #endif /* CONFIG_FLATMEM */
102 high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
105 mem_init_print_info(NULL);
109 void __init setup_bootmem(void)
111 phys_addr_t mem_start = 0;
112 phys_addr_t start, dram_end, end = 0;
113 phys_addr_t vmlinux_end = __pa_symbol(&_end);
114 phys_addr_t vmlinux_start = __pa_symbol(&_start);
115 phys_addr_t max_mapped_addr = __pa(~(ulong)0);
118 /* Find the memory region containing the kernel */
119 for_each_mem_range(i, &start, &end) {
120 phys_addr_t size = end - start;
123 if (start <= vmlinux_start && vmlinux_end <= end)
128 * The maximal physical memory size is -PAGE_OFFSET.
129 * Make sure that any memory beyond mem_start + (-PAGE_OFFSET) is removed
130 * as it is unusable by kernel.
132 memblock_enforce_memory_limit(-PAGE_OFFSET);
134 /* Reserve from the start of the kernel to the end of the kernel */
135 memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
137 dram_end = memblock_end_of_DRAM();
140 * memblock allocator is not aware of the fact that last 4K bytes of
141 * the addressable memory can not be mapped because of IS_ERR_VALUE
142 * macro. Make sure that last 4k bytes are not usable by memblock
143 * if end of dram is equal to maximum addressable memory.
145 if (max_mapped_addr == (dram_end - 1))
146 memblock_set_current_limit(max_mapped_addr - 4096);
148 max_pfn = PFN_DOWN(dram_end);
149 max_low_pfn = max_pfn;
150 dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
151 set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
153 reserve_initrd_mem();
155 * If DTB is built in, no need to reserve its memblock.
156 * Otherwise, do reserve it but avoid using
157 * early_init_fdt_reserve_self() since __pa() does
158 * not work for DTB pointers that are fixmap addresses
160 if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
161 memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
163 early_init_fdt_scan_reserved_mem();
164 dma_contiguous_reserve(dma32_phys_limit);
165 memblock_allow_resize();
169 static struct pt_alloc_ops pt_ops;
171 unsigned long va_pa_offset;
172 EXPORT_SYMBOL(va_pa_offset);
173 unsigned long pfn_base;
174 EXPORT_SYMBOL(pfn_base);
176 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
177 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
178 pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
180 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
182 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
184 unsigned long addr = __fix_to_virt(idx);
187 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
189 ptep = &fixmap_pte[pte_index(addr)];
191 if (pgprot_val(prot))
192 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
194 pte_clear(&init_mm, addr, ptep);
195 local_flush_tlb_page(addr);
198 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
200 return (pte_t *)((uintptr_t)pa);
203 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
205 clear_fixmap(FIX_PTE);
206 return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
209 static inline pte_t *get_pte_virt_late(phys_addr_t pa)
211 return (pte_t *) __va(pa);
214 static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
217 * We only create PMD or PGD early mappings so we
218 * should never reach here with MMU disabled.
223 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
225 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
228 static phys_addr_t alloc_pte_late(uintptr_t va)
232 vaddr = __get_free_page(GFP_KERNEL);
233 if (!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)))
238 static void __init create_pte_mapping(pte_t *ptep,
239 uintptr_t va, phys_addr_t pa,
240 phys_addr_t sz, pgprot_t prot)
242 uintptr_t pte_idx = pte_index(va);
244 BUG_ON(sz != PAGE_SIZE);
246 if (pte_none(ptep[pte_idx]))
247 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
250 #ifndef __PAGETABLE_PMD_FOLDED
252 pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
253 pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
254 pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
255 pmd_t early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
257 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
259 /* Before MMU is enabled */
260 return (pmd_t *)((uintptr_t)pa);
263 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
265 clear_fixmap(FIX_PMD);
266 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
269 static pmd_t *get_pmd_virt_late(phys_addr_t pa)
271 return (pmd_t *) __va(pa);
274 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
276 BUG_ON((va - PAGE_OFFSET) >> PGDIR_SHIFT);
278 return (uintptr_t)early_pmd;
281 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
283 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
286 static phys_addr_t alloc_pmd_late(uintptr_t va)
290 vaddr = __get_free_page(GFP_KERNEL);
295 static void __init create_pmd_mapping(pmd_t *pmdp,
296 uintptr_t va, phys_addr_t pa,
297 phys_addr_t sz, pgprot_t prot)
300 phys_addr_t pte_phys;
301 uintptr_t pmd_idx = pmd_index(va);
303 if (sz == PMD_SIZE) {
304 if (pmd_none(pmdp[pmd_idx]))
305 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
309 if (pmd_none(pmdp[pmd_idx])) {
310 pte_phys = pt_ops.alloc_pte(va);
311 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
312 ptep = pt_ops.get_pte_virt(pte_phys);
313 memset(ptep, 0, PAGE_SIZE);
315 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
316 ptep = pt_ops.get_pte_virt(pte_phys);
319 create_pte_mapping(ptep, va, pa, sz, prot);
322 #define pgd_next_t pmd_t
323 #define alloc_pgd_next(__va) pt_ops.alloc_pmd(__va)
324 #define get_pgd_next_virt(__pa) pt_ops.get_pmd_virt(__pa)
325 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
326 create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
327 #define fixmap_pgd_next fixmap_pmd
329 #define pgd_next_t pte_t
330 #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va)
331 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
332 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
333 create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
334 #define fixmap_pgd_next fixmap_pte
337 void __init create_pgd_mapping(pgd_t *pgdp,
338 uintptr_t va, phys_addr_t pa,
339 phys_addr_t sz, pgprot_t prot)
342 phys_addr_t next_phys;
343 uintptr_t pgd_idx = pgd_index(va);
345 if (sz == PGDIR_SIZE) {
346 if (pgd_val(pgdp[pgd_idx]) == 0)
347 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
351 if (pgd_val(pgdp[pgd_idx]) == 0) {
352 next_phys = alloc_pgd_next(va);
353 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
354 nextp = get_pgd_next_virt(next_phys);
355 memset(nextp, 0, PAGE_SIZE);
357 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
358 nextp = get_pgd_next_virt(next_phys);
361 create_pgd_next_mapping(nextp, va, pa, sz, prot);
364 static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
366 /* Upgrade to PMD_SIZE mappings whenever possible */
367 if ((base & (PMD_SIZE - 1)) || (size & (PMD_SIZE - 1)))
374 * setup_vm() is called from head.S with MMU-off.
376 * Following requirements should be honoured for setup_vm() to work
378 * 1) It should use PC-relative addressing for accessing kernel symbols.
379 * To achieve this we always use GCC cmodel=medany.
380 * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
381 * so disable compiler instrumentation when FTRACE is enabled.
383 * Currently, the above requirements are honoured by using custom CFLAGS
384 * for init.o in mm/Makefile.
387 #ifndef __riscv_cmodel_medany
388 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
391 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
393 uintptr_t va, pa, end_va;
394 uintptr_t load_pa = (uintptr_t)(&_start);
395 uintptr_t load_sz = (uintptr_t)(&_end) - load_pa;
397 #ifndef __PAGETABLE_PMD_FOLDED
398 pmd_t fix_bmap_spmd, fix_bmap_epmd;
401 va_pa_offset = PAGE_OFFSET - load_pa;
402 pfn_base = PFN_DOWN(load_pa);
405 * Enforce boot alignment requirements of RV32 and
406 * RV64 by only allowing PMD or PGD mappings.
410 /* Sanity check alignment and size */
411 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
412 BUG_ON((load_pa % map_size) != 0);
414 pt_ops.alloc_pte = alloc_pte_early;
415 pt_ops.get_pte_virt = get_pte_virt_early;
416 #ifndef __PAGETABLE_PMD_FOLDED
417 pt_ops.alloc_pmd = alloc_pmd_early;
418 pt_ops.get_pmd_virt = get_pmd_virt_early;
420 /* Setup early PGD for fixmap */
421 create_pgd_mapping(early_pg_dir, FIXADDR_START,
422 (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
424 #ifndef __PAGETABLE_PMD_FOLDED
425 /* Setup fixmap PMD */
426 create_pmd_mapping(fixmap_pmd, FIXADDR_START,
427 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
428 /* Setup trampoline PGD and PMD */
429 create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
430 (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
431 create_pmd_mapping(trampoline_pmd, PAGE_OFFSET,
432 load_pa, PMD_SIZE, PAGE_KERNEL_EXEC);
434 /* Setup trampoline PGD */
435 create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
436 load_pa, PGDIR_SIZE, PAGE_KERNEL_EXEC);
440 * Setup early PGD covering entire kernel which will allows
441 * us to reach paging_init(). We map all memory banks later
442 * in setup_vm_final() below.
444 end_va = PAGE_OFFSET + load_sz;
445 for (va = PAGE_OFFSET; va < end_va; va += map_size)
446 create_pgd_mapping(early_pg_dir, va,
447 load_pa + (va - PAGE_OFFSET),
448 map_size, PAGE_KERNEL_EXEC);
450 #ifndef __PAGETABLE_PMD_FOLDED
451 /* Setup early PMD for DTB */
452 create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
453 (uintptr_t)early_dtb_pmd, PGDIR_SIZE, PAGE_TABLE);
454 #ifndef CONFIG_BUILTIN_DTB
455 /* Create two consecutive PMD mappings for FDT early scan */
456 pa = dtb_pa & ~(PMD_SIZE - 1);
457 create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA,
458 pa, PMD_SIZE, PAGE_KERNEL);
459 create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA + PMD_SIZE,
460 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
461 dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE - 1));
462 #else /* CONFIG_BUILTIN_DTB */
463 dtb_early_va = __va(dtb_pa);
464 #endif /* CONFIG_BUILTIN_DTB */
466 #ifndef CONFIG_BUILTIN_DTB
467 /* Create two consecutive PGD mappings for FDT early scan */
468 pa = dtb_pa & ~(PGDIR_SIZE - 1);
469 create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
470 pa, PGDIR_SIZE, PAGE_KERNEL);
471 create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA + PGDIR_SIZE,
472 pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL);
473 dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE - 1));
474 #else /* CONFIG_BUILTIN_DTB */
475 dtb_early_va = __va(dtb_pa);
476 #endif /* CONFIG_BUILTIN_DTB */
478 dtb_early_pa = dtb_pa;
481 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
482 * range can not span multiple pmds.
484 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
485 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
487 #ifndef __PAGETABLE_PMD_FOLDED
489 * Early ioremap fixmap is already created as it lies within first 2MB
490 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
491 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
494 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
495 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
496 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
498 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
499 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
500 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
501 fix_to_virt(FIX_BTMAP_BEGIN));
502 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
503 fix_to_virt(FIX_BTMAP_END));
505 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
506 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
511 static void __init setup_vm_final(void)
513 uintptr_t va, map_size;
514 phys_addr_t pa, start, end;
518 * MMU is enabled at this point. But page table setup is not complete yet.
519 * fixmap page table alloc functions should be used at this point
521 pt_ops.alloc_pte = alloc_pte_fixmap;
522 pt_ops.get_pte_virt = get_pte_virt_fixmap;
523 #ifndef __PAGETABLE_PMD_FOLDED
524 pt_ops.alloc_pmd = alloc_pmd_fixmap;
525 pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
527 /* Setup swapper PGD for fixmap */
528 create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
529 __pa_symbol(fixmap_pgd_next),
530 PGDIR_SIZE, PAGE_TABLE);
532 /* Map all memory banks */
533 for_each_mem_range(i, &start, &end) {
536 if (start <= __pa(PAGE_OFFSET) &&
537 __pa(PAGE_OFFSET) < end)
538 start = __pa(PAGE_OFFSET);
540 map_size = best_map_size(start, end - start);
541 for (pa = start; pa < end; pa += map_size) {
542 va = (uintptr_t)__va(pa);
543 create_pgd_mapping(swapper_pg_dir, va, pa,
544 map_size, PAGE_KERNEL_EXEC);
548 /* Clear fixmap PTE and PMD mappings */
549 clear_fixmap(FIX_PTE);
550 clear_fixmap(FIX_PMD);
552 /* Move to swapper page table */
553 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
554 local_flush_tlb_all();
556 /* generic page allocation functions must be used to setup page table */
557 pt_ops.alloc_pte = alloc_pte_late;
558 pt_ops.get_pte_virt = get_pte_virt_late;
559 #ifndef __PAGETABLE_PMD_FOLDED
560 pt_ops.alloc_pmd = alloc_pmd_late;
561 pt_ops.get_pmd_virt = get_pmd_virt_late;
565 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
567 dtb_early_va = (void *)dtb_pa;
568 dtb_early_pa = dtb_pa;
571 static inline void setup_vm_final(void)
574 #endif /* CONFIG_MMU */
576 #ifdef CONFIG_STRICT_KERNEL_RWX
577 void protect_kernel_text_data(void)
579 unsigned long text_start = (unsigned long)_start;
580 unsigned long init_text_start = (unsigned long)__init_text_begin;
581 unsigned long init_data_start = (unsigned long)__init_data_begin;
582 unsigned long rodata_start = (unsigned long)__start_rodata;
583 unsigned long data_start = (unsigned long)_data;
584 unsigned long max_low = (unsigned long)(__va(PFN_PHYS(max_low_pfn)));
586 set_memory_ro(text_start, (init_text_start - text_start) >> PAGE_SHIFT);
587 set_memory_ro(init_text_start, (init_data_start - init_text_start) >> PAGE_SHIFT);
588 set_memory_nx(init_data_start, (rodata_start - init_data_start) >> PAGE_SHIFT);
589 /* rodata section is marked readonly in mark_rodata_ro */
590 set_memory_nx(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
591 set_memory_nx(data_start, (max_low - data_start) >> PAGE_SHIFT);
594 void mark_rodata_ro(void)
596 unsigned long rodata_start = (unsigned long)__start_rodata;
597 unsigned long data_start = (unsigned long)_data;
599 set_memory_ro(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
605 void __init paging_init(void)
611 void __init misc_mem_init(void)
619 #ifdef CONFIG_SPARSEMEM_VMEMMAP
620 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
621 struct vmem_altmap *altmap)
623 return vmemmap_populate_basepages(start, end, node, NULL);