xref: /openbmc/linux/arch/riscv/mm/init.c (revision f7af616c)
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  * Copyright (C) 2020 FORTH-ICS/CARV
6  *  Nick Kossifidis <mick@ics.forth.gr>
7  */
8 
9 #include <linux/init.h>
10 #include <linux/mm.h>
11 #include <linux/memblock.h>
12 #include <linux/initrd.h>
13 #include <linux/swap.h>
14 #include <linux/sizes.h>
15 #include <linux/of_fdt.h>
16 #include <linux/of_reserved_mem.h>
17 #include <linux/libfdt.h>
18 #include <linux/set_memory.h>
19 #include <linux/dma-map-ops.h>
20 #include <linux/crash_dump.h>
21 
22 #include <asm/fixmap.h>
23 #include <asm/tlbflush.h>
24 #include <asm/sections.h>
25 #include <asm/soc.h>
26 #include <asm/io.h>
27 #include <asm/ptdump.h>
28 #include <asm/numa.h>
29 
30 #include "../kernel/head.h"
31 
32 unsigned long kernel_virt_addr = KERNEL_LINK_ADDR;
33 EXPORT_SYMBOL(kernel_virt_addr);
34 #ifdef CONFIG_XIP_KERNEL
35 #define kernel_virt_addr       (*((unsigned long *)XIP_FIXUP(&kernel_virt_addr)))
36 #endif
37 
38 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
39 							__page_aligned_bss;
40 EXPORT_SYMBOL(empty_zero_page);
41 
42 extern char _start[];
43 #define DTB_EARLY_BASE_VA      PGDIR_SIZE
44 void *_dtb_early_va __initdata;
45 uintptr_t _dtb_early_pa __initdata;
46 
47 struct pt_alloc_ops {
48 	pte_t *(*get_pte_virt)(phys_addr_t pa);
49 	phys_addr_t (*alloc_pte)(uintptr_t va);
50 #ifndef __PAGETABLE_PMD_FOLDED
51 	pmd_t *(*get_pmd_virt)(phys_addr_t pa);
52 	phys_addr_t (*alloc_pmd)(uintptr_t va);
53 #endif
54 };
55 
56 static phys_addr_t dma32_phys_limit __ro_after_init;
57 
58 static void __init zone_sizes_init(void)
59 {
60 	unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
61 
62 #ifdef CONFIG_ZONE_DMA32
63 	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
64 #endif
65 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
66 
67 	free_area_init(max_zone_pfns);
68 }
69 
70 static void __init setup_zero_page(void)
71 {
72 	memset((void *)empty_zero_page, 0, PAGE_SIZE);
73 }
74 
75 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
76 static inline void print_mlk(char *name, unsigned long b, unsigned long t)
77 {
78 	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld kB)\n", name, b, t,
79 		  (((t) - (b)) >> 10));
80 }
81 
82 static inline void print_mlm(char *name, unsigned long b, unsigned long t)
83 {
84 	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld MB)\n", name, b, t,
85 		  (((t) - (b)) >> 20));
86 }
87 
88 static void __init print_vm_layout(void)
89 {
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);
101 #ifdef CONFIG_64BIT
102 	print_mlm("kernel", (unsigned long)KERNEL_LINK_ADDR,
103 		  (unsigned long)ADDRESS_SPACE_END);
104 #endif
105 }
106 #else
107 static void print_vm_layout(void) { }
108 #endif /* CONFIG_DEBUG_VM */
109 
110 void __init mem_init(void)
111 {
112 #ifdef CONFIG_FLATMEM
113 	BUG_ON(!mem_map);
114 #endif /* CONFIG_FLATMEM */
115 
116 	high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
117 	memblock_free_all();
118 
119 	print_vm_layout();
120 }
121 
122 void __init setup_bootmem(void)
123 {
124 	phys_addr_t vmlinux_end = __pa_symbol(&_end);
125 	phys_addr_t vmlinux_start = __pa_symbol(&_start);
126 	phys_addr_t dram_end = memblock_end_of_DRAM();
127 	phys_addr_t max_mapped_addr = __pa(~(ulong)0);
128 
129 #ifdef CONFIG_XIP_KERNEL
130 	vmlinux_start = __pa_symbol(&_sdata);
131 #endif
132 
133 	/* The maximal physical memory size is -PAGE_OFFSET. */
134 	memblock_enforce_memory_limit(-PAGE_OFFSET);
135 
136 	/*
137 	 * Reserve from the start of the kernel to the end of the kernel
138 	 */
139 #if defined(CONFIG_64BIT) && defined(CONFIG_STRICT_KERNEL_RWX)
140 	/*
141 	 * Make sure we align the reservation on PMD_SIZE since we will
142 	 * map the kernel in the linear mapping as read-only: we do not want
143 	 * any allocation to happen between _end and the next pmd aligned page.
144 	 */
145 	vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK;
146 #endif
147 	memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
148 
149 	/*
150 	 * memblock allocator is not aware of the fact that last 4K bytes of
151 	 * the addressable memory can not be mapped because of IS_ERR_VALUE
152 	 * macro. Make sure that last 4k bytes are not usable by memblock
153 	 * if end of dram is equal to maximum addressable memory.
154 	 */
155 	if (max_mapped_addr == (dram_end - 1))
156 		memblock_set_current_limit(max_mapped_addr - 4096);
157 
158 	min_low_pfn = PFN_UP(memblock_start_of_DRAM());
159 	max_low_pfn = max_pfn = PFN_DOWN(dram_end);
160 
161 	dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
162 	set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
163 
164 	reserve_initrd_mem();
165 	/*
166 	 * If DTB is built in, no need to reserve its memblock.
167 	 * Otherwise, do reserve it but avoid using
168 	 * early_init_fdt_reserve_self() since __pa() does
169 	 * not work for DTB pointers that are fixmap addresses
170 	 */
171 	if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
172 		memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
173 
174 	early_init_fdt_scan_reserved_mem();
175 	dma_contiguous_reserve(dma32_phys_limit);
176 	memblock_allow_resize();
177 }
178 
179 #ifdef CONFIG_XIP_KERNEL
180 
181 extern char _xiprom[], _exiprom[];
182 extern char _sdata[], _edata[];
183 
184 #endif /* CONFIG_XIP_KERNEL */
185 
186 #ifdef CONFIG_MMU
187 static struct pt_alloc_ops _pt_ops __ro_after_init;
188 
189 #ifdef CONFIG_XIP_KERNEL
190 #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&_pt_ops))
191 #else
192 #define pt_ops _pt_ops
193 #endif
194 
195 /* Offset between linear mapping virtual address and kernel load address */
196 unsigned long va_pa_offset __ro_after_init;
197 EXPORT_SYMBOL(va_pa_offset);
198 #ifdef CONFIG_XIP_KERNEL
199 #define va_pa_offset   (*((unsigned long *)XIP_FIXUP(&va_pa_offset)))
200 #endif
201 /* Offset between kernel mapping virtual address and kernel load address */
202 #ifdef CONFIG_64BIT
203 unsigned long va_kernel_pa_offset;
204 EXPORT_SYMBOL(va_kernel_pa_offset);
205 #endif
206 #ifdef CONFIG_XIP_KERNEL
207 #define va_kernel_pa_offset    (*((unsigned long *)XIP_FIXUP(&va_kernel_pa_offset)))
208 #endif
209 unsigned long va_kernel_xip_pa_offset;
210 EXPORT_SYMBOL(va_kernel_xip_pa_offset);
211 #ifdef CONFIG_XIP_KERNEL
212 #define va_kernel_xip_pa_offset        (*((unsigned long *)XIP_FIXUP(&va_kernel_xip_pa_offset)))
213 #endif
214 unsigned long pfn_base __ro_after_init;
215 EXPORT_SYMBOL(pfn_base);
216 
217 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
218 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
219 pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
220 
221 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
222 
223 #ifdef CONFIG_XIP_KERNEL
224 #define trampoline_pg_dir      ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
225 #define fixmap_pte             ((pte_t *)XIP_FIXUP(fixmap_pte))
226 #define early_pg_dir           ((pgd_t *)XIP_FIXUP(early_pg_dir))
227 #endif /* CONFIG_XIP_KERNEL */
228 
229 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
230 {
231 	unsigned long addr = __fix_to_virt(idx);
232 	pte_t *ptep;
233 
234 	BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
235 
236 	ptep = &fixmap_pte[pte_index(addr)];
237 
238 	if (pgprot_val(prot))
239 		set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
240 	else
241 		pte_clear(&init_mm, addr, ptep);
242 	local_flush_tlb_page(addr);
243 }
244 
245 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
246 {
247 	return (pte_t *)((uintptr_t)pa);
248 }
249 
250 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
251 {
252 	clear_fixmap(FIX_PTE);
253 	return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
254 }
255 
256 static inline pte_t *get_pte_virt_late(phys_addr_t pa)
257 {
258 	return (pte_t *) __va(pa);
259 }
260 
261 static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
262 {
263 	/*
264 	 * We only create PMD or PGD early mappings so we
265 	 * should never reach here with MMU disabled.
266 	 */
267 	BUG();
268 }
269 
270 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
271 {
272 	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
273 }
274 
275 static phys_addr_t alloc_pte_late(uintptr_t va)
276 {
277 	unsigned long vaddr;
278 
279 	vaddr = __get_free_page(GFP_KERNEL);
280 	BUG_ON(!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)));
281 
282 	return __pa(vaddr);
283 }
284 
285 static void __init create_pte_mapping(pte_t *ptep,
286 				      uintptr_t va, phys_addr_t pa,
287 				      phys_addr_t sz, pgprot_t prot)
288 {
289 	uintptr_t pte_idx = pte_index(va);
290 
291 	BUG_ON(sz != PAGE_SIZE);
292 
293 	if (pte_none(ptep[pte_idx]))
294 		ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
295 }
296 
297 #ifndef __PAGETABLE_PMD_FOLDED
298 
299 pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
300 pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
301 pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
302 pmd_t early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
303 
304 #ifdef CONFIG_XIP_KERNEL
305 #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd))
306 #define fixmap_pmd     ((pmd_t *)XIP_FIXUP(fixmap_pmd))
307 #define early_pmd      ((pmd_t *)XIP_FIXUP(early_pmd))
308 #endif /* CONFIG_XIP_KERNEL */
309 
310 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
311 {
312 	/* Before MMU is enabled */
313 	return (pmd_t *)((uintptr_t)pa);
314 }
315 
316 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
317 {
318 	clear_fixmap(FIX_PMD);
319 	return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
320 }
321 
322 static pmd_t *get_pmd_virt_late(phys_addr_t pa)
323 {
324 	return (pmd_t *) __va(pa);
325 }
326 
327 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
328 {
329 	BUG_ON((va - kernel_virt_addr) >> PGDIR_SHIFT);
330 
331 	return (uintptr_t)early_pmd;
332 }
333 
334 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
335 {
336 	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
337 }
338 
339 static phys_addr_t alloc_pmd_late(uintptr_t va)
340 {
341 	unsigned long vaddr;
342 
343 	vaddr = __get_free_page(GFP_KERNEL);
344 	BUG_ON(!vaddr);
345 	return __pa(vaddr);
346 }
347 
348 static void __init create_pmd_mapping(pmd_t *pmdp,
349 				      uintptr_t va, phys_addr_t pa,
350 				      phys_addr_t sz, pgprot_t prot)
351 {
352 	pte_t *ptep;
353 	phys_addr_t pte_phys;
354 	uintptr_t pmd_idx = pmd_index(va);
355 
356 	if (sz == PMD_SIZE) {
357 		if (pmd_none(pmdp[pmd_idx]))
358 			pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
359 		return;
360 	}
361 
362 	if (pmd_none(pmdp[pmd_idx])) {
363 		pte_phys = pt_ops.alloc_pte(va);
364 		pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
365 		ptep = pt_ops.get_pte_virt(pte_phys);
366 		memset(ptep, 0, PAGE_SIZE);
367 	} else {
368 		pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
369 		ptep = pt_ops.get_pte_virt(pte_phys);
370 	}
371 
372 	create_pte_mapping(ptep, va, pa, sz, prot);
373 }
374 
375 #define pgd_next_t		pmd_t
376 #define alloc_pgd_next(__va)	pt_ops.alloc_pmd(__va)
377 #define get_pgd_next_virt(__pa)	pt_ops.get_pmd_virt(__pa)
378 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
379 	create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
380 #define fixmap_pgd_next		fixmap_pmd
381 #else
382 #define pgd_next_t		pte_t
383 #define alloc_pgd_next(__va)	pt_ops.alloc_pte(__va)
384 #define get_pgd_next_virt(__pa)	pt_ops.get_pte_virt(__pa)
385 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
386 	create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
387 #define fixmap_pgd_next		fixmap_pte
388 #endif
389 
390 void __init create_pgd_mapping(pgd_t *pgdp,
391 				      uintptr_t va, phys_addr_t pa,
392 				      phys_addr_t sz, pgprot_t prot)
393 {
394 	pgd_next_t *nextp;
395 	phys_addr_t next_phys;
396 	uintptr_t pgd_idx = pgd_index(va);
397 
398 	if (sz == PGDIR_SIZE) {
399 		if (pgd_val(pgdp[pgd_idx]) == 0)
400 			pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
401 		return;
402 	}
403 
404 	if (pgd_val(pgdp[pgd_idx]) == 0) {
405 		next_phys = alloc_pgd_next(va);
406 		pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
407 		nextp = get_pgd_next_virt(next_phys);
408 		memset(nextp, 0, PAGE_SIZE);
409 	} else {
410 		next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
411 		nextp = get_pgd_next_virt(next_phys);
412 	}
413 
414 	create_pgd_next_mapping(nextp, va, pa, sz, prot);
415 }
416 
417 static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
418 {
419 	/* Upgrade to PMD_SIZE mappings whenever possible */
420 	if ((base & (PMD_SIZE - 1)) || (size & (PMD_SIZE - 1)))
421 		return PAGE_SIZE;
422 
423 	return PMD_SIZE;
424 }
425 
426 #ifdef CONFIG_XIP_KERNEL
427 /* called from head.S with MMU off */
428 asmlinkage void __init __copy_data(void)
429 {
430 	void *from = (void *)(&_sdata);
431 	void *end = (void *)(&_end);
432 	void *to = (void *)CONFIG_PHYS_RAM_BASE;
433 	size_t sz = (size_t)(end - from + 1);
434 
435 	memcpy(to, from, sz);
436 }
437 #endif
438 
439 /*
440  * setup_vm() is called from head.S with MMU-off.
441  *
442  * Following requirements should be honoured for setup_vm() to work
443  * correctly:
444  * 1) It should use PC-relative addressing for accessing kernel symbols.
445  *    To achieve this we always use GCC cmodel=medany.
446  * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
447  *    so disable compiler instrumentation when FTRACE is enabled.
448  *
449  * Currently, the above requirements are honoured by using custom CFLAGS
450  * for init.o in mm/Makefile.
451  */
452 
453 #ifndef __riscv_cmodel_medany
454 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
455 #endif
456 
457 uintptr_t load_pa, load_sz;
458 #ifdef CONFIG_XIP_KERNEL
459 #define load_pa        (*((uintptr_t *)XIP_FIXUP(&load_pa)))
460 #define load_sz        (*((uintptr_t *)XIP_FIXUP(&load_sz)))
461 #endif
462 
463 #ifdef CONFIG_XIP_KERNEL
464 uintptr_t xiprom, xiprom_sz;
465 #define xiprom_sz      (*((uintptr_t *)XIP_FIXUP(&xiprom_sz)))
466 #define xiprom         (*((uintptr_t *)XIP_FIXUP(&xiprom)))
467 
468 static void __init create_kernel_page_table(pgd_t *pgdir, uintptr_t map_size)
469 {
470 	uintptr_t va, end_va;
471 
472 	/* Map the flash resident part */
473 	end_va = kernel_virt_addr + xiprom_sz;
474 	for (va = kernel_virt_addr; va < end_va; va += map_size)
475 		create_pgd_mapping(pgdir, va,
476 				   xiprom + (va - kernel_virt_addr),
477 				   map_size, PAGE_KERNEL_EXEC);
478 
479 	/* Map the data in RAM */
480 	end_va = kernel_virt_addr + XIP_OFFSET + load_sz;
481 	for (va = kernel_virt_addr + XIP_OFFSET; va < end_va; va += map_size)
482 		create_pgd_mapping(pgdir, va,
483 				   load_pa + (va - (kernel_virt_addr + XIP_OFFSET)),
484 				   map_size, PAGE_KERNEL);
485 }
486 #else
487 static void __init create_kernel_page_table(pgd_t *pgdir, uintptr_t map_size)
488 {
489 	uintptr_t va, end_va;
490 
491 	end_va = kernel_virt_addr + load_sz;
492 	for (va = kernel_virt_addr; va < end_va; va += map_size)
493 		create_pgd_mapping(pgdir, va,
494 				   load_pa + (va - kernel_virt_addr),
495 				   map_size, PAGE_KERNEL_EXEC);
496 }
497 #endif
498 
499 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
500 {
501 	uintptr_t __maybe_unused pa;
502 	uintptr_t map_size;
503 #ifndef __PAGETABLE_PMD_FOLDED
504 	pmd_t fix_bmap_spmd, fix_bmap_epmd;
505 #endif
506 
507 #ifdef CONFIG_XIP_KERNEL
508 	xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
509 	xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
510 
511 	load_pa = (uintptr_t)CONFIG_PHYS_RAM_BASE;
512 	load_sz = (uintptr_t)(&_end) - (uintptr_t)(&_sdata);
513 
514 	va_kernel_xip_pa_offset = kernel_virt_addr - xiprom;
515 #else
516 	load_pa = (uintptr_t)(&_start);
517 	load_sz = (uintptr_t)(&_end) - load_pa;
518 #endif
519 
520 	va_pa_offset = PAGE_OFFSET - load_pa;
521 #ifdef CONFIG_64BIT
522 	va_kernel_pa_offset = kernel_virt_addr - load_pa;
523 #endif
524 
525 	pfn_base = PFN_DOWN(load_pa);
526 
527 	/*
528 	 * Enforce boot alignment requirements of RV32 and
529 	 * RV64 by only allowing PMD or PGD mappings.
530 	 */
531 	map_size = PMD_SIZE;
532 
533 	/* Sanity check alignment and size */
534 	BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
535 	BUG_ON((load_pa % map_size) != 0);
536 
537 	pt_ops.alloc_pte = alloc_pte_early;
538 	pt_ops.get_pte_virt = get_pte_virt_early;
539 #ifndef __PAGETABLE_PMD_FOLDED
540 	pt_ops.alloc_pmd = alloc_pmd_early;
541 	pt_ops.get_pmd_virt = get_pmd_virt_early;
542 #endif
543 	/* Setup early PGD for fixmap */
544 	create_pgd_mapping(early_pg_dir, FIXADDR_START,
545 			   (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
546 
547 #ifndef __PAGETABLE_PMD_FOLDED
548 	/* Setup fixmap PMD */
549 	create_pmd_mapping(fixmap_pmd, FIXADDR_START,
550 			   (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
551 	/* Setup trampoline PGD and PMD */
552 	create_pgd_mapping(trampoline_pg_dir, kernel_virt_addr,
553 			   (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
554 #ifdef CONFIG_XIP_KERNEL
555 	create_pmd_mapping(trampoline_pmd, kernel_virt_addr,
556 			   xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
557 #else
558 	create_pmd_mapping(trampoline_pmd, kernel_virt_addr,
559 			   load_pa, PMD_SIZE, PAGE_KERNEL_EXEC);
560 #endif
561 #else
562 	/* Setup trampoline PGD */
563 	create_pgd_mapping(trampoline_pg_dir, kernel_virt_addr,
564 			   load_pa, PGDIR_SIZE, PAGE_KERNEL_EXEC);
565 #endif
566 
567 	/*
568 	 * Setup early PGD covering entire kernel which will allow
569 	 * us to reach paging_init(). We map all memory banks later
570 	 * in setup_vm_final() below.
571 	 */
572 	create_kernel_page_table(early_pg_dir, map_size);
573 
574 #ifndef __PAGETABLE_PMD_FOLDED
575 	/* Setup early PMD for DTB */
576 	create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
577 			   (uintptr_t)early_dtb_pmd, PGDIR_SIZE, PAGE_TABLE);
578 #ifndef CONFIG_BUILTIN_DTB
579 	/* Create two consecutive PMD mappings for FDT early scan */
580 	pa = dtb_pa & ~(PMD_SIZE - 1);
581 	create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA,
582 			   pa, PMD_SIZE, PAGE_KERNEL);
583 	create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA + PMD_SIZE,
584 			   pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
585 	dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE - 1));
586 #else /* CONFIG_BUILTIN_DTB */
587 #ifdef CONFIG_64BIT
588 	/*
589 	 * __va can't be used since it would return a linear mapping address
590 	 * whereas dtb_early_va will be used before setup_vm_final installs
591 	 * the linear mapping.
592 	 */
593 	dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
594 #else
595 	dtb_early_va = __va(dtb_pa);
596 #endif /* CONFIG_64BIT */
597 #endif /* CONFIG_BUILTIN_DTB */
598 #else
599 #ifndef CONFIG_BUILTIN_DTB
600 	/* Create two consecutive PGD mappings for FDT early scan */
601 	pa = dtb_pa & ~(PGDIR_SIZE - 1);
602 	create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
603 			   pa, PGDIR_SIZE, PAGE_KERNEL);
604 	create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA + PGDIR_SIZE,
605 			   pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL);
606 	dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE - 1));
607 #else /* CONFIG_BUILTIN_DTB */
608 #ifdef CONFIG_64BIT
609 	dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
610 #else
611 	dtb_early_va = __va(dtb_pa);
612 #endif /* CONFIG_64BIT */
613 #endif /* CONFIG_BUILTIN_DTB */
614 #endif
615 	dtb_early_pa = dtb_pa;
616 
617 	/*
618 	 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
619 	 * range can not span multiple pmds.
620 	 */
621 	BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
622 		     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
623 
624 #ifndef __PAGETABLE_PMD_FOLDED
625 	/*
626 	 * Early ioremap fixmap is already created as it lies within first 2MB
627 	 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
628 	 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
629 	 * the user if not.
630 	 */
631 	fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
632 	fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
633 	if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
634 		WARN_ON(1);
635 		pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
636 			pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
637 		pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
638 			fix_to_virt(FIX_BTMAP_BEGIN));
639 		pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
640 			fix_to_virt(FIX_BTMAP_END));
641 
642 		pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
643 		pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
644 	}
645 #endif
646 }
647 
648 #if defined(CONFIG_64BIT) && defined(CONFIG_STRICT_KERNEL_RWX)
649 void protect_kernel_linear_mapping_text_rodata(void)
650 {
651 	unsigned long text_start = (unsigned long)lm_alias(_start);
652 	unsigned long init_text_start = (unsigned long)lm_alias(__init_text_begin);
653 	unsigned long rodata_start = (unsigned long)lm_alias(__start_rodata);
654 	unsigned long data_start = (unsigned long)lm_alias(_data);
655 
656 	set_memory_ro(text_start, (init_text_start - text_start) >> PAGE_SHIFT);
657 	set_memory_nx(text_start, (init_text_start - text_start) >> PAGE_SHIFT);
658 
659 	set_memory_ro(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
660 	set_memory_nx(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
661 }
662 #endif
663 
664 static void __init setup_vm_final(void)
665 {
666 	uintptr_t va, map_size;
667 	phys_addr_t pa, start, end;
668 	u64 i;
669 
670 	/**
671 	 * MMU is enabled at this point. But page table setup is not complete yet.
672 	 * fixmap page table alloc functions should be used at this point
673 	 */
674 	pt_ops.alloc_pte = alloc_pte_fixmap;
675 	pt_ops.get_pte_virt = get_pte_virt_fixmap;
676 #ifndef __PAGETABLE_PMD_FOLDED
677 	pt_ops.alloc_pmd = alloc_pmd_fixmap;
678 	pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
679 #endif
680 	/* Setup swapper PGD for fixmap */
681 	create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
682 			   __pa_symbol(fixmap_pgd_next),
683 			   PGDIR_SIZE, PAGE_TABLE);
684 
685 	/* Map all memory banks in the linear mapping */
686 	for_each_mem_range(i, &start, &end) {
687 		if (start >= end)
688 			break;
689 		if (start <= __pa(PAGE_OFFSET) &&
690 		    __pa(PAGE_OFFSET) < end)
691 			start = __pa(PAGE_OFFSET);
692 
693 		map_size = best_map_size(start, end - start);
694 		for (pa = start; pa < end; pa += map_size) {
695 			va = (uintptr_t)__va(pa);
696 			create_pgd_mapping(swapper_pg_dir, va, pa,
697 					   map_size,
698 #ifdef CONFIG_64BIT
699 					   PAGE_KERNEL
700 #else
701 					   PAGE_KERNEL_EXEC
702 #endif
703 					);
704 
705 		}
706 	}
707 
708 #ifdef CONFIG_64BIT
709 	/* Map the kernel */
710 	create_kernel_page_table(swapper_pg_dir, PMD_SIZE);
711 #endif
712 
713 	/* Clear fixmap PTE and PMD mappings */
714 	clear_fixmap(FIX_PTE);
715 	clear_fixmap(FIX_PMD);
716 
717 	/* Move to swapper page table */
718 	csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
719 	local_flush_tlb_all();
720 
721 	/* generic page allocation functions must be used to setup page table */
722 	pt_ops.alloc_pte = alloc_pte_late;
723 	pt_ops.get_pte_virt = get_pte_virt_late;
724 #ifndef __PAGETABLE_PMD_FOLDED
725 	pt_ops.alloc_pmd = alloc_pmd_late;
726 	pt_ops.get_pmd_virt = get_pmd_virt_late;
727 #endif
728 }
729 #else
730 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
731 {
732 	dtb_early_va = (void *)dtb_pa;
733 	dtb_early_pa = dtb_pa;
734 }
735 
736 static inline void setup_vm_final(void)
737 {
738 }
739 #endif /* CONFIG_MMU */
740 
741 #ifdef CONFIG_STRICT_KERNEL_RWX
742 void __init protect_kernel_text_data(void)
743 {
744 	unsigned long text_start = (unsigned long)_start;
745 	unsigned long init_text_start = (unsigned long)__init_text_begin;
746 	unsigned long init_data_start = (unsigned long)__init_data_begin;
747 	unsigned long rodata_start = (unsigned long)__start_rodata;
748 	unsigned long data_start = (unsigned long)_data;
749 	unsigned long max_low = (unsigned long)(__va(PFN_PHYS(max_low_pfn)));
750 
751 	set_memory_ro(text_start, (init_text_start - text_start) >> PAGE_SHIFT);
752 	set_memory_ro(init_text_start, (init_data_start - init_text_start) >> PAGE_SHIFT);
753 	set_memory_nx(init_data_start, (rodata_start - init_data_start) >> PAGE_SHIFT);
754 	/* rodata section is marked readonly in mark_rodata_ro */
755 	set_memory_nx(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
756 	set_memory_nx(data_start, (max_low - data_start) >> PAGE_SHIFT);
757 }
758 
759 void mark_rodata_ro(void)
760 {
761 	unsigned long rodata_start = (unsigned long)__start_rodata;
762 	unsigned long data_start = (unsigned long)_data;
763 
764 	set_memory_ro(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
765 
766 	debug_checkwx();
767 }
768 #endif
769 
770 #ifdef CONFIG_KEXEC_CORE
771 /*
772  * reserve_crashkernel() - reserves memory for crash kernel
773  *
774  * This function reserves memory area given in "crashkernel=" kernel command
775  * line parameter. The memory reserved is used by dump capture kernel when
776  * primary kernel is crashing.
777  */
778 static void __init reserve_crashkernel(void)
779 {
780 	unsigned long long crash_base = 0;
781 	unsigned long long crash_size = 0;
782 	unsigned long search_start = memblock_start_of_DRAM();
783 	unsigned long search_end = memblock_end_of_DRAM();
784 
785 	int ret = 0;
786 
787 	/*
788 	 * Don't reserve a region for a crash kernel on a crash kernel
789 	 * since it doesn't make much sense and we have limited memory
790 	 * resources.
791 	 */
792 #ifdef CONFIG_CRASH_DUMP
793 	if (is_kdump_kernel()) {
794 		pr_info("crashkernel: ignoring reservation request\n");
795 		return;
796 	}
797 #endif
798 
799 	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),
800 				&crash_size, &crash_base);
801 	if (ret || !crash_size)
802 		return;
803 
804 	crash_size = PAGE_ALIGN(crash_size);
805 
806 	if (crash_base == 0) {
807 		/*
808 		 * Current riscv boot protocol requires 2MB alignment for
809 		 * RV64 and 4MB alignment for RV32 (hugepage size)
810 		 */
811 		crash_base = memblock_find_in_range(search_start, search_end,
812 						    crash_size, PMD_SIZE);
813 
814 		if (crash_base == 0) {
815 			pr_warn("crashkernel: couldn't allocate %lldKB\n",
816 				crash_size >> 10);
817 			return;
818 		}
819 	} else {
820 		/* User specifies base address explicitly. */
821 		if (!memblock_is_region_memory(crash_base, crash_size)) {
822 			pr_warn("crashkernel: requested region is not memory\n");
823 			return;
824 		}
825 
826 		if (memblock_is_region_reserved(crash_base, crash_size)) {
827 			pr_warn("crashkernel: requested region is reserved\n");
828 			return;
829 		}
830 
831 
832 		if (!IS_ALIGNED(crash_base, PMD_SIZE)) {
833 			pr_warn("crashkernel: requested region is misaligned\n");
834 			return;
835 		}
836 	}
837 	memblock_reserve(crash_base, crash_size);
838 
839 	pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",
840 		crash_base, crash_base + crash_size, crash_size >> 20);
841 
842 	crashk_res.start = crash_base;
843 	crashk_res.end = crash_base + crash_size - 1;
844 }
845 #endif /* CONFIG_KEXEC_CORE */
846 
847 #ifdef CONFIG_CRASH_DUMP
848 /*
849  * We keep track of the ELF core header of the crashed
850  * kernel with a reserved-memory region with compatible
851  * string "linux,elfcorehdr". Here we register a callback
852  * to populate elfcorehdr_addr/size when this region is
853  * present. Note that this region will be marked as
854  * reserved once we call early_init_fdt_scan_reserved_mem()
855  * later on.
856  */
857 static int elfcore_hdr_setup(struct reserved_mem *rmem)
858 {
859 	elfcorehdr_addr = rmem->base;
860 	elfcorehdr_size = rmem->size;
861 	return 0;
862 }
863 
864 RESERVEDMEM_OF_DECLARE(elfcorehdr, "linux,elfcorehdr", elfcore_hdr_setup);
865 #endif
866 
867 void __init paging_init(void)
868 {
869 	setup_vm_final();
870 	setup_zero_page();
871 }
872 
873 void __init misc_mem_init(void)
874 {
875 	early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
876 	arch_numa_init();
877 	sparse_init();
878 	zone_sizes_init();
879 #ifdef CONFIG_KEXEC_CORE
880 	reserve_crashkernel();
881 #endif
882 	memblock_dump_all();
883 }
884 
885 #ifdef CONFIG_SPARSEMEM_VMEMMAP
886 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
887 			       struct vmem_altmap *altmap)
888 {
889 	return vmemmap_populate_basepages(start, end, node, NULL);
890 }
891 #endif
892