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.
5 * Copyright (C) 2020 FORTH-ICS/CARV
6 * Nick Kossifidis <mick@ics.forth.gr>
9 #include <linux/init.h>
11 #include <linux/memblock.h>
12 #include <linux/initrd.h>
13 #include <linux/swap.h>
14 #include <linux/swiotlb.h>
15 #include <linux/sizes.h>
16 #include <linux/of_fdt.h>
17 #include <linux/of_reserved_mem.h>
18 #include <linux/libfdt.h>
19 #include <linux/set_memory.h>
20 #include <linux/dma-map-ops.h>
21 #include <linux/crash_dump.h>
23 #include <asm/fixmap.h>
24 #include <asm/tlbflush.h>
25 #include <asm/sections.h>
28 #include <asm/ptdump.h>
31 #include "../kernel/head.h"
33 struct kernel_mapping kernel_map __ro_after_init;
34 EXPORT_SYMBOL(kernel_map);
35 #ifdef CONFIG_XIP_KERNEL
36 #define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map))
39 #ifdef CONFIG_XIP_KERNEL
40 extern char _xiprom[], _exiprom[];
43 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
45 EXPORT_SYMBOL(empty_zero_page);
48 #define DTB_EARLY_BASE_VA PGDIR_SIZE
49 void *_dtb_early_va __initdata;
50 uintptr_t _dtb_early_pa __initdata;
53 pte_t *(*get_pte_virt)(phys_addr_t pa);
54 phys_addr_t (*alloc_pte)(uintptr_t va);
55 #ifndef __PAGETABLE_PMD_FOLDED
56 pmd_t *(*get_pmd_virt)(phys_addr_t pa);
57 phys_addr_t (*alloc_pmd)(uintptr_t va);
61 static phys_addr_t dma32_phys_limit __initdata;
63 static void __init zone_sizes_init(void)
65 unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
67 #ifdef CONFIG_ZONE_DMA32
68 max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
70 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
72 free_area_init(max_zone_pfns);
75 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
76 static inline void print_mlk(char *name, unsigned long b, unsigned long t)
78 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t,
82 static inline void print_mlm(char *name, unsigned long b, unsigned long t)
84 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t,
88 static void __init print_vm_layout(void)
90 pr_notice("Virtual kernel memory layout:\n");
91 print_mlk("fixmap", (unsigned long)FIXADDR_START,
92 (unsigned long)FIXADDR_TOP);
93 print_mlm("pci io", (unsigned long)PCI_IO_START,
94 (unsigned long)PCI_IO_END);
95 print_mlm("vmemmap", (unsigned long)VMEMMAP_START,
96 (unsigned long)VMEMMAP_END);
97 print_mlm("vmalloc", (unsigned long)VMALLOC_START,
98 (unsigned long)VMALLOC_END);
99 print_mlm("lowmem", (unsigned long)PAGE_OFFSET,
100 (unsigned long)high_memory);
102 print_mlm("kernel", (unsigned long)KERNEL_LINK_ADDR,
103 (unsigned long)ADDRESS_SPACE_END);
107 static void print_vm_layout(void) { }
108 #endif /* CONFIG_DEBUG_VM */
110 void __init mem_init(void)
112 #ifdef CONFIG_FLATMEM
114 #endif /* CONFIG_FLATMEM */
116 #ifdef CONFIG_SWIOTLB
117 if (swiotlb_force == SWIOTLB_FORCE ||
118 max_pfn > PFN_DOWN(dma32_phys_limit))
121 swiotlb_force = SWIOTLB_NO_FORCE;
123 high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
130 * The default maximal physical memory size is -PAGE_OFFSET for 32-bit kernel,
131 * whereas for 64-bit kernel, the end of the virtual address space is occupied
132 * by the modules/BPF/kernel mappings which reduces the available size of the
134 * Limit the memory size via mem.
137 static phys_addr_t memory_limit = -PAGE_OFFSET - SZ_4G;
139 static phys_addr_t memory_limit = -PAGE_OFFSET;
142 static int __init early_mem(char *p)
149 size = memparse(p, &p) & PAGE_MASK;
150 memory_limit = min_t(u64, size, memory_limit);
152 pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20);
156 early_param("mem", early_mem);
158 static void __init setup_bootmem(void)
160 phys_addr_t vmlinux_end = __pa_symbol(&_end);
161 phys_addr_t vmlinux_start = __pa_symbol(&_start);
162 phys_addr_t __maybe_unused max_mapped_addr;
163 phys_addr_t dram_end;
165 #ifdef CONFIG_XIP_KERNEL
166 vmlinux_start = __pa_symbol(&_sdata);
169 memblock_enforce_memory_limit(memory_limit);
172 * Reserve from the start of the kernel to the end of the kernel
174 #if defined(CONFIG_64BIT) && defined(CONFIG_STRICT_KERNEL_RWX)
176 * Make sure we align the reservation on PMD_SIZE since we will
177 * map the kernel in the linear mapping as read-only: we do not want
178 * any allocation to happen between _end and the next pmd aligned page.
180 vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK;
182 memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
184 dram_end = memblock_end_of_DRAM();
188 * memblock allocator is not aware of the fact that last 4K bytes of
189 * the addressable memory can not be mapped because of IS_ERR_VALUE
190 * macro. Make sure that last 4k bytes are not usable by memblock
191 * if end of dram is equal to maximum addressable memory. For 64-bit
192 * kernel, this problem can't happen here as the end of the virtual
193 * address space is occupied by the kernel mapping then this check must
194 * be done in create_kernel_page_table.
196 max_mapped_addr = __pa(~(ulong)0);
197 if (max_mapped_addr == (dram_end - 1))
198 memblock_set_current_limit(max_mapped_addr - 4096);
201 min_low_pfn = PFN_UP(memblock_start_of_DRAM());
202 max_low_pfn = max_pfn = PFN_DOWN(dram_end);
204 dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
205 set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
207 reserve_initrd_mem();
209 * If DTB is built in, no need to reserve its memblock.
210 * Otherwise, do reserve it but avoid using
211 * early_init_fdt_reserve_self() since __pa() does
212 * not work for DTB pointers that are fixmap addresses
214 if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
215 memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
217 early_init_fdt_scan_reserved_mem();
218 dma_contiguous_reserve(dma32_phys_limit);
219 memblock_allow_resize();
223 static struct pt_alloc_ops _pt_ops __initdata;
225 #ifdef CONFIG_XIP_KERNEL
226 #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&_pt_ops))
228 #define pt_ops _pt_ops
231 unsigned long pfn_base __ro_after_init;
232 EXPORT_SYMBOL(pfn_base);
234 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
235 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
236 static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
238 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
240 #ifdef CONFIG_XIP_KERNEL
241 #define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
242 #define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte))
243 #define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir))
244 #endif /* CONFIG_XIP_KERNEL */
246 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
248 unsigned long addr = __fix_to_virt(idx);
251 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
253 ptep = &fixmap_pte[pte_index(addr)];
255 if (pgprot_val(prot))
256 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
258 pte_clear(&init_mm, addr, ptep);
259 local_flush_tlb_page(addr);
262 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
264 return (pte_t *)((uintptr_t)pa);
267 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
269 clear_fixmap(FIX_PTE);
270 return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
273 static inline pte_t *__init get_pte_virt_late(phys_addr_t pa)
275 return (pte_t *) __va(pa);
278 static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
281 * We only create PMD or PGD early mappings so we
282 * should never reach here with MMU disabled.
287 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
289 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
292 static phys_addr_t __init alloc_pte_late(uintptr_t va)
296 vaddr = __get_free_page(GFP_KERNEL);
297 BUG_ON(!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)));
302 static void __init create_pte_mapping(pte_t *ptep,
303 uintptr_t va, phys_addr_t pa,
304 phys_addr_t sz, pgprot_t prot)
306 uintptr_t pte_idx = pte_index(va);
308 BUG_ON(sz != PAGE_SIZE);
310 if (pte_none(ptep[pte_idx]))
311 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
314 #ifndef __PAGETABLE_PMD_FOLDED
316 static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
317 static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
318 static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
319 static pmd_t early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
321 #ifdef CONFIG_XIP_KERNEL
322 #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd))
323 #define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd))
324 #define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd))
325 #endif /* CONFIG_XIP_KERNEL */
327 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
329 /* Before MMU is enabled */
330 return (pmd_t *)((uintptr_t)pa);
333 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
335 clear_fixmap(FIX_PMD);
336 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
339 static pmd_t *__init get_pmd_virt_late(phys_addr_t pa)
341 return (pmd_t *) __va(pa);
344 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
346 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
348 return (uintptr_t)early_pmd;
351 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
353 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
356 static phys_addr_t __init alloc_pmd_late(uintptr_t va)
360 vaddr = __get_free_page(GFP_KERNEL);
365 static void __init create_pmd_mapping(pmd_t *pmdp,
366 uintptr_t va, phys_addr_t pa,
367 phys_addr_t sz, pgprot_t prot)
370 phys_addr_t pte_phys;
371 uintptr_t pmd_idx = pmd_index(va);
373 if (sz == PMD_SIZE) {
374 if (pmd_none(pmdp[pmd_idx]))
375 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
379 if (pmd_none(pmdp[pmd_idx])) {
380 pte_phys = pt_ops.alloc_pte(va);
381 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
382 ptep = pt_ops.get_pte_virt(pte_phys);
383 memset(ptep, 0, PAGE_SIZE);
385 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
386 ptep = pt_ops.get_pte_virt(pte_phys);
389 create_pte_mapping(ptep, va, pa, sz, prot);
392 #define pgd_next_t pmd_t
393 #define alloc_pgd_next(__va) pt_ops.alloc_pmd(__va)
394 #define get_pgd_next_virt(__pa) pt_ops.get_pmd_virt(__pa)
395 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
396 create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
397 #define fixmap_pgd_next fixmap_pmd
399 #define pgd_next_t pte_t
400 #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va)
401 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
402 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
403 create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
404 #define fixmap_pgd_next fixmap_pte
407 void __init create_pgd_mapping(pgd_t *pgdp,
408 uintptr_t va, phys_addr_t pa,
409 phys_addr_t sz, pgprot_t prot)
412 phys_addr_t next_phys;
413 uintptr_t pgd_idx = pgd_index(va);
415 if (sz == PGDIR_SIZE) {
416 if (pgd_val(pgdp[pgd_idx]) == 0)
417 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
421 if (pgd_val(pgdp[pgd_idx]) == 0) {
422 next_phys = alloc_pgd_next(va);
423 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
424 nextp = get_pgd_next_virt(next_phys);
425 memset(nextp, 0, PAGE_SIZE);
427 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
428 nextp = get_pgd_next_virt(next_phys);
431 create_pgd_next_mapping(nextp, va, pa, sz, prot);
434 static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
436 /* Upgrade to PMD_SIZE mappings whenever possible */
437 if ((base & (PMD_SIZE - 1)) || (size & (PMD_SIZE - 1)))
443 #ifdef CONFIG_XIP_KERNEL
444 /* called from head.S with MMU off */
445 asmlinkage void __init __copy_data(void)
447 void *from = (void *)(&_sdata);
448 void *end = (void *)(&_end);
449 void *to = (void *)CONFIG_PHYS_RAM_BASE;
450 size_t sz = (size_t)(end - from + 1);
452 memcpy(to, from, sz);
456 #ifdef CONFIG_STRICT_KERNEL_RWX
457 static __init pgprot_t pgprot_from_va(uintptr_t va)
459 if (is_va_kernel_text(va))
460 return PAGE_KERNEL_READ_EXEC;
463 * In 64-bit kernel, the kernel mapping is outside the linear mapping so
464 * we must protect its linear mapping alias from being executed and
466 * And rodata section is marked readonly in mark_rodata_ro.
468 if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va))
469 return PAGE_KERNEL_READ;
474 void mark_rodata_ro(void)
476 set_kernel_memory(__start_rodata, _data, set_memory_ro);
477 if (IS_ENABLED(CONFIG_64BIT))
478 set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data),
484 static __init pgprot_t pgprot_from_va(uintptr_t va)
486 if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va))
489 return PAGE_KERNEL_EXEC;
491 #endif /* CONFIG_STRICT_KERNEL_RWX */
494 * setup_vm() is called from head.S with MMU-off.
496 * Following requirements should be honoured for setup_vm() to work
498 * 1) It should use PC-relative addressing for accessing kernel symbols.
499 * To achieve this we always use GCC cmodel=medany.
500 * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
501 * so disable compiler instrumentation when FTRACE is enabled.
503 * Currently, the above requirements are honoured by using custom CFLAGS
504 * for init.o in mm/Makefile.
507 #ifndef __riscv_cmodel_medany
508 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
511 #ifdef CONFIG_XIP_KERNEL
512 static void __init create_kernel_page_table(pgd_t *pgdir, uintptr_t map_size,
513 __always_unused bool early)
515 uintptr_t va, end_va;
517 /* Map the flash resident part */
518 end_va = kernel_map.virt_addr + kernel_map.xiprom_sz;
519 for (va = kernel_map.virt_addr; va < end_va; va += map_size)
520 create_pgd_mapping(pgdir, va,
521 kernel_map.xiprom + (va - kernel_map.virt_addr),
522 map_size, PAGE_KERNEL_EXEC);
524 /* Map the data in RAM */
525 end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size;
526 for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += map_size)
527 create_pgd_mapping(pgdir, va,
528 kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)),
529 map_size, PAGE_KERNEL);
532 static void __init create_kernel_page_table(pgd_t *pgdir, uintptr_t map_size,
535 uintptr_t va, end_va;
537 end_va = kernel_map.virt_addr + kernel_map.size;
538 for (va = kernel_map.virt_addr; va < end_va; va += map_size)
539 create_pgd_mapping(pgdir, va,
540 kernel_map.phys_addr + (va - kernel_map.virt_addr),
543 PAGE_KERNEL_EXEC : pgprot_from_va(va));
547 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
549 uintptr_t __maybe_unused pa;
551 #ifndef __PAGETABLE_PMD_FOLDED
552 pmd_t fix_bmap_spmd, fix_bmap_epmd;
555 kernel_map.virt_addr = KERNEL_LINK_ADDR;
557 #ifdef CONFIG_XIP_KERNEL
558 kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
559 kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
561 kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE;
562 kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata);
564 kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom;
566 kernel_map.phys_addr = (uintptr_t)(&_start);
567 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
570 kernel_map.va_pa_offset = PAGE_OFFSET - kernel_map.phys_addr;
572 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
575 pfn_base = PFN_DOWN(kernel_map.phys_addr);
578 * Enforce boot alignment requirements of RV32 and
579 * RV64 by only allowing PMD or PGD mappings.
583 /* Sanity check alignment and size */
584 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
585 BUG_ON((kernel_map.phys_addr % map_size) != 0);
589 * The last 4K bytes of the addressable memory can not be mapped because
590 * of IS_ERR_VALUE macro.
592 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K);
595 pt_ops.alloc_pte = alloc_pte_early;
596 pt_ops.get_pte_virt = get_pte_virt_early;
597 #ifndef __PAGETABLE_PMD_FOLDED
598 pt_ops.alloc_pmd = alloc_pmd_early;
599 pt_ops.get_pmd_virt = get_pmd_virt_early;
601 /* Setup early PGD for fixmap */
602 create_pgd_mapping(early_pg_dir, FIXADDR_START,
603 (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
605 #ifndef __PAGETABLE_PMD_FOLDED
606 /* Setup fixmap PMD */
607 create_pmd_mapping(fixmap_pmd, FIXADDR_START,
608 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
609 /* Setup trampoline PGD and PMD */
610 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
611 (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
612 #ifdef CONFIG_XIP_KERNEL
613 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
614 kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
616 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
617 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC);
620 /* Setup trampoline PGD */
621 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
622 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC);
626 * Setup early PGD covering entire kernel which will allow
627 * us to reach paging_init(). We map all memory banks later
628 * in setup_vm_final() below.
630 create_kernel_page_table(early_pg_dir, map_size, true);
632 #ifndef __PAGETABLE_PMD_FOLDED
633 /* Setup early PMD for DTB */
634 create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
635 (uintptr_t)early_dtb_pmd, PGDIR_SIZE, PAGE_TABLE);
636 #ifndef CONFIG_BUILTIN_DTB
637 /* Create two consecutive PMD mappings for FDT early scan */
638 pa = dtb_pa & ~(PMD_SIZE - 1);
639 create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA,
640 pa, PMD_SIZE, PAGE_KERNEL);
641 create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA + PMD_SIZE,
642 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
643 dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE - 1));
644 #else /* CONFIG_BUILTIN_DTB */
647 * __va can't be used since it would return a linear mapping address
648 * whereas dtb_early_va will be used before setup_vm_final installs
649 * the linear mapping.
651 dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
653 dtb_early_va = __va(dtb_pa);
654 #endif /* CONFIG_64BIT */
655 #endif /* CONFIG_BUILTIN_DTB */
657 #ifndef CONFIG_BUILTIN_DTB
658 /* Create two consecutive PGD mappings for FDT early scan */
659 pa = dtb_pa & ~(PGDIR_SIZE - 1);
660 create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
661 pa, PGDIR_SIZE, PAGE_KERNEL);
662 create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA + PGDIR_SIZE,
663 pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL);
664 dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE - 1));
665 #else /* CONFIG_BUILTIN_DTB */
667 dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
669 dtb_early_va = __va(dtb_pa);
670 #endif /* CONFIG_64BIT */
671 #endif /* CONFIG_BUILTIN_DTB */
673 dtb_early_pa = dtb_pa;
676 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
677 * range can not span multiple pmds.
679 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
680 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
682 #ifndef __PAGETABLE_PMD_FOLDED
684 * Early ioremap fixmap is already created as it lies within first 2MB
685 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
686 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
689 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
690 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
691 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
693 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
694 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
695 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
696 fix_to_virt(FIX_BTMAP_BEGIN));
697 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
698 fix_to_virt(FIX_BTMAP_END));
700 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
701 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
706 static void __init setup_vm_final(void)
708 uintptr_t va, map_size;
709 phys_addr_t pa, start, end;
713 * MMU is enabled at this point. But page table setup is not complete yet.
714 * fixmap page table alloc functions should be used at this point
716 pt_ops.alloc_pte = alloc_pte_fixmap;
717 pt_ops.get_pte_virt = get_pte_virt_fixmap;
718 #ifndef __PAGETABLE_PMD_FOLDED
719 pt_ops.alloc_pmd = alloc_pmd_fixmap;
720 pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
722 /* Setup swapper PGD for fixmap */
723 create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
724 __pa_symbol(fixmap_pgd_next),
725 PGDIR_SIZE, PAGE_TABLE);
727 /* Map all memory banks in the linear mapping */
728 for_each_mem_range(i, &start, &end) {
731 if (start <= __pa(PAGE_OFFSET) &&
732 __pa(PAGE_OFFSET) < end)
733 start = __pa(PAGE_OFFSET);
734 if (end >= __pa(PAGE_OFFSET) + memory_limit)
735 end = __pa(PAGE_OFFSET) + memory_limit;
737 map_size = best_map_size(start, end - start);
738 for (pa = start; pa < end; pa += map_size) {
739 va = (uintptr_t)__va(pa);
741 create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
748 create_kernel_page_table(swapper_pg_dir, PMD_SIZE, false);
751 /* Clear fixmap PTE and PMD mappings */
752 clear_fixmap(FIX_PTE);
753 clear_fixmap(FIX_PMD);
755 /* Move to swapper page table */
756 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
757 local_flush_tlb_all();
759 /* generic page allocation functions must be used to setup page table */
760 pt_ops.alloc_pte = alloc_pte_late;
761 pt_ops.get_pte_virt = get_pte_virt_late;
762 #ifndef __PAGETABLE_PMD_FOLDED
763 pt_ops.alloc_pmd = alloc_pmd_late;
764 pt_ops.get_pmd_virt = get_pmd_virt_late;
768 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
770 dtb_early_va = (void *)dtb_pa;
771 dtb_early_pa = dtb_pa;
774 static inline void setup_vm_final(void)
777 #endif /* CONFIG_MMU */
779 #ifdef CONFIG_KEXEC_CORE
781 * reserve_crashkernel() - reserves memory for crash kernel
783 * This function reserves memory area given in "crashkernel=" kernel command
784 * line parameter. The memory reserved is used by dump capture kernel when
785 * primary kernel is crashing.
787 static void __init reserve_crashkernel(void)
789 unsigned long long crash_base = 0;
790 unsigned long long crash_size = 0;
791 unsigned long search_start = memblock_start_of_DRAM();
792 unsigned long search_end = memblock_end_of_DRAM();
797 * Don't reserve a region for a crash kernel on a crash kernel
798 * since it doesn't make much sense and we have limited memory
801 #ifdef CONFIG_CRASH_DUMP
802 if (is_kdump_kernel()) {
803 pr_info("crashkernel: ignoring reservation request\n");
808 ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
809 &crash_size, &crash_base);
810 if (ret || !crash_size)
813 crash_size = PAGE_ALIGN(crash_size);
815 if (crash_base == 0) {
817 * Current riscv boot protocol requires 2MB alignment for
818 * RV64 and 4MB alignment for RV32 (hugepage size)
820 crash_base = memblock_find_in_range(search_start, search_end,
821 crash_size, PMD_SIZE);
823 if (crash_base == 0) {
824 pr_warn("crashkernel: couldn't allocate %lldKB\n",
829 /* User specifies base address explicitly. */
830 if (!memblock_is_region_memory(crash_base, crash_size)) {
831 pr_warn("crashkernel: requested region is not memory\n");
835 if (memblock_is_region_reserved(crash_base, crash_size)) {
836 pr_warn("crashkernel: requested region is reserved\n");
841 if (!IS_ALIGNED(crash_base, PMD_SIZE)) {
842 pr_warn("crashkernel: requested region is misaligned\n");
846 memblock_reserve(crash_base, crash_size);
848 pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",
849 crash_base, crash_base + crash_size, crash_size >> 20);
851 crashk_res.start = crash_base;
852 crashk_res.end = crash_base + crash_size - 1;
854 #endif /* CONFIG_KEXEC_CORE */
856 #ifdef CONFIG_CRASH_DUMP
858 * We keep track of the ELF core header of the crashed
859 * kernel with a reserved-memory region with compatible
860 * string "linux,elfcorehdr". Here we register a callback
861 * to populate elfcorehdr_addr/size when this region is
862 * present. Note that this region will be marked as
863 * reserved once we call early_init_fdt_scan_reserved_mem()
866 static int __init elfcore_hdr_setup(struct reserved_mem *rmem)
868 elfcorehdr_addr = rmem->base;
869 elfcorehdr_size = rmem->size;
873 RESERVEDMEM_OF_DECLARE(elfcorehdr, "linux,elfcorehdr", elfcore_hdr_setup);
876 void __init paging_init(void)
882 void __init misc_mem_init(void)
884 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
888 #ifdef CONFIG_KEXEC_CORE
889 reserve_crashkernel();
894 #ifdef CONFIG_SPARSEMEM_VMEMMAP
895 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
896 struct vmem_altmap *altmap)
898 return vmemmap_populate_basepages(start, end, node, NULL);