xref: /openbmc/linux/arch/riscv/mm/init.c (revision abe9af53)
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 pmd_t early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
297 
298 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
299 {
300 	/* Before MMU is enabled */
301 	return (pmd_t *)((uintptr_t)pa);
302 }
303 
304 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
305 {
306 	clear_fixmap(FIX_PMD);
307 	return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
308 }
309 
310 static pmd_t *get_pmd_virt_late(phys_addr_t pa)
311 {
312 	return (pmd_t *) __va(pa);
313 }
314 
315 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
316 {
317 	uintptr_t pmd_num;
318 
319 	pmd_num = (va - PAGE_OFFSET) >> PGDIR_SHIFT;
320 	BUG_ON(pmd_num >= NUM_EARLY_PMDS);
321 	return (uintptr_t)&early_pmd[pmd_num * PTRS_PER_PMD];
322 }
323 
324 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
325 {
326 	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
327 }
328 
329 static phys_addr_t alloc_pmd_late(uintptr_t va)
330 {
331 	unsigned long vaddr;
332 
333 	vaddr = __get_free_page(GFP_KERNEL);
334 	BUG_ON(!vaddr);
335 	return __pa(vaddr);
336 }
337 
338 static void __init create_pmd_mapping(pmd_t *pmdp,
339 				      uintptr_t va, phys_addr_t pa,
340 				      phys_addr_t sz, pgprot_t prot)
341 {
342 	pte_t *ptep;
343 	phys_addr_t pte_phys;
344 	uintptr_t pmd_idx = pmd_index(va);
345 
346 	if (sz == PMD_SIZE) {
347 		if (pmd_none(pmdp[pmd_idx]))
348 			pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
349 		return;
350 	}
351 
352 	if (pmd_none(pmdp[pmd_idx])) {
353 		pte_phys = pt_ops.alloc_pte(va);
354 		pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
355 		ptep = pt_ops.get_pte_virt(pte_phys);
356 		memset(ptep, 0, PAGE_SIZE);
357 	} else {
358 		pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
359 		ptep = pt_ops.get_pte_virt(pte_phys);
360 	}
361 
362 	create_pte_mapping(ptep, va, pa, sz, prot);
363 }
364 
365 #define pgd_next_t		pmd_t
366 #define alloc_pgd_next(__va)	pt_ops.alloc_pmd(__va)
367 #define get_pgd_next_virt(__pa)	pt_ops.get_pmd_virt(__pa)
368 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
369 	create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
370 #define fixmap_pgd_next		fixmap_pmd
371 #else
372 #define pgd_next_t		pte_t
373 #define alloc_pgd_next(__va)	pt_ops.alloc_pte(__va)
374 #define get_pgd_next_virt(__pa)	pt_ops.get_pte_virt(__pa)
375 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
376 	create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
377 #define fixmap_pgd_next		fixmap_pte
378 #endif
379 
380 void __init create_pgd_mapping(pgd_t *pgdp,
381 				      uintptr_t va, phys_addr_t pa,
382 				      phys_addr_t sz, pgprot_t prot)
383 {
384 	pgd_next_t *nextp;
385 	phys_addr_t next_phys;
386 	uintptr_t pgd_idx = pgd_index(va);
387 
388 	if (sz == PGDIR_SIZE) {
389 		if (pgd_val(pgdp[pgd_idx]) == 0)
390 			pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
391 		return;
392 	}
393 
394 	if (pgd_val(pgdp[pgd_idx]) == 0) {
395 		next_phys = alloc_pgd_next(va);
396 		pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
397 		nextp = get_pgd_next_virt(next_phys);
398 		memset(nextp, 0, PAGE_SIZE);
399 	} else {
400 		next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
401 		nextp = get_pgd_next_virt(next_phys);
402 	}
403 
404 	create_pgd_next_mapping(nextp, va, pa, sz, prot);
405 }
406 
407 static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
408 {
409 	/* Upgrade to PMD_SIZE mappings whenever possible */
410 	if ((base & (PMD_SIZE - 1)) || (size & (PMD_SIZE - 1)))
411 		return PAGE_SIZE;
412 
413 	return PMD_SIZE;
414 }
415 
416 /*
417  * setup_vm() is called from head.S with MMU-off.
418  *
419  * Following requirements should be honoured for setup_vm() to work
420  * correctly:
421  * 1) It should use PC-relative addressing for accessing kernel symbols.
422  *    To achieve this we always use GCC cmodel=medany.
423  * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
424  *    so disable compiler instrumentation when FTRACE is enabled.
425  *
426  * Currently, the above requirements are honoured by using custom CFLAGS
427  * for init.o in mm/Makefile.
428  */
429 
430 #ifndef __riscv_cmodel_medany
431 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
432 #endif
433 
434 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
435 {
436 	uintptr_t va, pa, end_va;
437 	uintptr_t load_pa = (uintptr_t)(&_start);
438 	uintptr_t load_sz = (uintptr_t)(&_end) - load_pa;
439 	uintptr_t map_size = best_map_size(load_pa, MAX_EARLY_MAPPING_SIZE);
440 #ifndef __PAGETABLE_PMD_FOLDED
441 	pmd_t fix_bmap_spmd, fix_bmap_epmd;
442 #endif
443 
444 	va_pa_offset = PAGE_OFFSET - load_pa;
445 	pfn_base = PFN_DOWN(load_pa);
446 
447 	/*
448 	 * Enforce boot alignment requirements of RV32 and
449 	 * RV64 by only allowing PMD or PGD mappings.
450 	 */
451 	BUG_ON(map_size == PAGE_SIZE);
452 
453 	/* Sanity check alignment and size */
454 	BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
455 	BUG_ON((load_pa % map_size) != 0);
456 	BUG_ON(load_sz > MAX_EARLY_MAPPING_SIZE);
457 
458 	pt_ops.alloc_pte = alloc_pte_early;
459 	pt_ops.get_pte_virt = get_pte_virt_early;
460 #ifndef __PAGETABLE_PMD_FOLDED
461 	pt_ops.alloc_pmd = alloc_pmd_early;
462 	pt_ops.get_pmd_virt = get_pmd_virt_early;
463 #endif
464 	/* Setup early PGD for fixmap */
465 	create_pgd_mapping(early_pg_dir, FIXADDR_START,
466 			   (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
467 
468 #ifndef __PAGETABLE_PMD_FOLDED
469 	/* Setup fixmap PMD */
470 	create_pmd_mapping(fixmap_pmd, FIXADDR_START,
471 			   (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
472 	/* Setup trampoline PGD and PMD */
473 	create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
474 			   (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
475 	create_pmd_mapping(trampoline_pmd, PAGE_OFFSET,
476 			   load_pa, PMD_SIZE, PAGE_KERNEL_EXEC);
477 #else
478 	/* Setup trampoline PGD */
479 	create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
480 			   load_pa, PGDIR_SIZE, PAGE_KERNEL_EXEC);
481 #endif
482 
483 	/*
484 	 * Setup early PGD covering entire kernel which will allows
485 	 * us to reach paging_init(). We map all memory banks later
486 	 * in setup_vm_final() below.
487 	 */
488 	end_va = PAGE_OFFSET + load_sz;
489 	for (va = PAGE_OFFSET; va < end_va; va += map_size)
490 		create_pgd_mapping(early_pg_dir, va,
491 				   load_pa + (va - PAGE_OFFSET),
492 				   map_size, PAGE_KERNEL_EXEC);
493 
494 #ifndef __PAGETABLE_PMD_FOLDED
495 	/* Setup early PMD for DTB */
496 	create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
497 			   (uintptr_t)early_dtb_pmd, PGDIR_SIZE, PAGE_TABLE);
498 	/* Create two consecutive PMD mappings for FDT early scan */
499 	pa = dtb_pa & ~(PMD_SIZE - 1);
500 	create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA,
501 			   pa, PMD_SIZE, PAGE_KERNEL);
502 	create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA + PMD_SIZE,
503 			   pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
504 	dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE - 1));
505 #else
506 	/* Create two consecutive PGD mappings for FDT early scan */
507 	pa = dtb_pa & ~(PGDIR_SIZE - 1);
508 	create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
509 			   pa, PGDIR_SIZE, PAGE_KERNEL);
510 	create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA + PGDIR_SIZE,
511 			   pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL);
512 	dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE - 1));
513 #endif
514 	dtb_early_pa = dtb_pa;
515 
516 	/*
517 	 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
518 	 * range can not span multiple pmds.
519 	 */
520 	BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
521 		     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
522 
523 #ifndef __PAGETABLE_PMD_FOLDED
524 	/*
525 	 * Early ioremap fixmap is already created as it lies within first 2MB
526 	 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
527 	 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
528 	 * the user if not.
529 	 */
530 	fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
531 	fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
532 	if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
533 		WARN_ON(1);
534 		pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
535 			pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
536 		pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
537 			fix_to_virt(FIX_BTMAP_BEGIN));
538 		pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
539 			fix_to_virt(FIX_BTMAP_END));
540 
541 		pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
542 		pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
543 	}
544 #endif
545 }
546 
547 static void __init setup_vm_final(void)
548 {
549 	uintptr_t va, map_size;
550 	phys_addr_t pa, start, end;
551 	u64 i;
552 
553 	/**
554 	 * MMU is enabled at this point. But page table setup is not complete yet.
555 	 * fixmap page table alloc functions should be used at this point
556 	 */
557 	pt_ops.alloc_pte = alloc_pte_fixmap;
558 	pt_ops.get_pte_virt = get_pte_virt_fixmap;
559 #ifndef __PAGETABLE_PMD_FOLDED
560 	pt_ops.alloc_pmd = alloc_pmd_fixmap;
561 	pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
562 #endif
563 	/* Setup swapper PGD for fixmap */
564 	create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
565 			   __pa_symbol(fixmap_pgd_next),
566 			   PGDIR_SIZE, PAGE_TABLE);
567 
568 	/* Map all memory banks */
569 	for_each_mem_range(i, &start, &end) {
570 		if (start >= end)
571 			break;
572 		if (start <= __pa(PAGE_OFFSET) &&
573 		    __pa(PAGE_OFFSET) < end)
574 			start = __pa(PAGE_OFFSET);
575 
576 		map_size = best_map_size(start, end - start);
577 		for (pa = start; pa < end; pa += map_size) {
578 			va = (uintptr_t)__va(pa);
579 			create_pgd_mapping(swapper_pg_dir, va, pa,
580 					   map_size, PAGE_KERNEL_EXEC);
581 		}
582 	}
583 
584 	/* Clear fixmap PTE and PMD mappings */
585 	clear_fixmap(FIX_PTE);
586 	clear_fixmap(FIX_PMD);
587 
588 	/* Move to swapper page table */
589 	csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
590 	local_flush_tlb_all();
591 
592 	/* generic page allocation functions must be used to setup page table */
593 	pt_ops.alloc_pte = alloc_pte_late;
594 	pt_ops.get_pte_virt = get_pte_virt_late;
595 #ifndef __PAGETABLE_PMD_FOLDED
596 	pt_ops.alloc_pmd = alloc_pmd_late;
597 	pt_ops.get_pmd_virt = get_pmd_virt_late;
598 #endif
599 }
600 #else
601 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
602 {
603 #ifdef CONFIG_BUILTIN_DTB
604 	dtb_early_va = soc_lookup_builtin_dtb();
605 	if (!dtb_early_va) {
606 		/* Fallback to first available DTS */
607 		dtb_early_va = (void *) __dtb_start;
608 	}
609 #else
610 	dtb_early_va = (void *)dtb_pa;
611 #endif
612 	dtb_early_pa = dtb_pa;
613 }
614 
615 static inline void setup_vm_final(void)
616 {
617 }
618 #endif /* CONFIG_MMU */
619 
620 #ifdef CONFIG_STRICT_KERNEL_RWX
621 void mark_rodata_ro(void)
622 {
623 	unsigned long text_start = (unsigned long)_text;
624 	unsigned long text_end = (unsigned long)_etext;
625 	unsigned long rodata_start = (unsigned long)__start_rodata;
626 	unsigned long data_start = (unsigned long)_data;
627 	unsigned long max_low = (unsigned long)(__va(PFN_PHYS(max_low_pfn)));
628 
629 	set_memory_ro(text_start, (text_end - text_start) >> PAGE_SHIFT);
630 	set_memory_ro(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
631 	set_memory_nx(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
632 	set_memory_nx(data_start, (max_low - data_start) >> PAGE_SHIFT);
633 
634 	debug_checkwx();
635 }
636 #endif
637 
638 static void __init resource_init(void)
639 {
640 	struct memblock_region *region;
641 
642 	for_each_mem_region(region) {
643 		struct resource *res;
644 
645 		res = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
646 		if (!res)
647 			panic("%s: Failed to allocate %zu bytes\n", __func__,
648 			      sizeof(struct resource));
649 
650 		if (memblock_is_nomap(region)) {
651 			res->name = "reserved";
652 			res->flags = IORESOURCE_MEM;
653 		} else {
654 			res->name = "System RAM";
655 			res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
656 		}
657 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
658 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
659 
660 		request_resource(&iomem_resource, res);
661 	}
662 }
663 
664 void __init paging_init(void)
665 {
666 	setup_vm_final();
667 	sparse_init();
668 	setup_zero_page();
669 	zone_sizes_init();
670 	resource_init();
671 }
672 
673 #ifdef CONFIG_SPARSEMEM_VMEMMAP
674 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
675 			       struct vmem_altmap *altmap)
676 {
677 	return vmemmap_populate_basepages(start, end, node, NULL);
678 }
679 #endif
680