Merge tag 'perf-tools-2020-12-19' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6-microblaze.git] / arch / riscv / mm / init.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 Regents of the University of California
4  * Copyright (C) 2019 Western Digital Corporation or its affiliates.
5  */
6
7 #include <linux/init.h>
8 #include <linux/mm.h>
9 #include <linux/memblock.h>
10 #include <linux/initrd.h>
11 #include <linux/swap.h>
12 #include <linux/sizes.h>
13 #include <linux/of_fdt.h>
14 #include <linux/libfdt.h>
15 #include <linux/set_memory.h>
16 #include <linux/dma-map-ops.h>
17
18 #include <asm/fixmap.h>
19 #include <asm/tlbflush.h>
20 #include <asm/sections.h>
21 #include <asm/soc.h>
22 #include <asm/io.h>
23 #include <asm/ptdump.h>
24
25 #include "../kernel/head.h"
26
27 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
28                                                         __page_aligned_bss;
29 EXPORT_SYMBOL(empty_zero_page);
30
31 extern char _start[];
32 #define DTB_EARLY_BASE_VA      PGDIR_SIZE
33 void *dtb_early_va __initdata;
34 uintptr_t dtb_early_pa __initdata;
35
36 struct pt_alloc_ops {
37         pte_t *(*get_pte_virt)(phys_addr_t pa);
38         phys_addr_t (*alloc_pte)(uintptr_t va);
39 #ifndef __PAGETABLE_PMD_FOLDED
40         pmd_t *(*get_pmd_virt)(phys_addr_t pa);
41         phys_addr_t (*alloc_pmd)(uintptr_t va);
42 #endif
43 };
44
45 static phys_addr_t dma32_phys_limit __ro_after_init;
46
47 static void __init zone_sizes_init(void)
48 {
49         unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
50
51 #ifdef CONFIG_ZONE_DMA32
52         max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
53 #endif
54         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
55
56         free_area_init(max_zone_pfns);
57 }
58
59 static void setup_zero_page(void)
60 {
61         memset((void *)empty_zero_page, 0, PAGE_SIZE);
62 }
63
64 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
65 static inline void print_mlk(char *name, unsigned long b, unsigned long t)
66 {
67         pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld kB)\n", name, b, t,
68                   (((t) - (b)) >> 10));
69 }
70
71 static inline void print_mlm(char *name, unsigned long b, unsigned long t)
72 {
73         pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld MB)\n", name, b, t,
74                   (((t) - (b)) >> 20));
75 }
76
77 static void print_vm_layout(void)
78 {
79         pr_notice("Virtual kernel memory layout:\n");
80         print_mlk("fixmap", (unsigned long)FIXADDR_START,
81                   (unsigned long)FIXADDR_TOP);
82         print_mlm("pci io", (unsigned long)PCI_IO_START,
83                   (unsigned long)PCI_IO_END);
84         print_mlm("vmemmap", (unsigned long)VMEMMAP_START,
85                   (unsigned long)VMEMMAP_END);
86         print_mlm("vmalloc", (unsigned long)VMALLOC_START,
87                   (unsigned long)VMALLOC_END);
88         print_mlm("lowmem", (unsigned long)PAGE_OFFSET,
89                   (unsigned long)high_memory);
90 }
91 #else
92 static void print_vm_layout(void) { }
93 #endif /* CONFIG_DEBUG_VM */
94
95 void __init mem_init(void)
96 {
97 #ifdef CONFIG_FLATMEM
98         BUG_ON(!mem_map);
99 #endif /* CONFIG_FLATMEM */
100
101         high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
102         memblock_free_all();
103
104         mem_init_print_info(NULL);
105         print_vm_layout();
106 }
107
108 #ifdef CONFIG_BLK_DEV_INITRD
109 static void __init setup_initrd(void)
110 {
111         phys_addr_t start;
112         unsigned long size;
113
114         /* Ignore the virtul address computed during device tree parsing */
115         initrd_start = initrd_end = 0;
116
117         if (!phys_initrd_size)
118                 return;
119         /*
120          * Round the memory region to page boundaries as per free_initrd_mem()
121          * This allows us to detect whether the pages overlapping the initrd
122          * are in use, but more importantly, reserves the entire set of pages
123          * as we don't want these pages allocated for other purposes.
124          */
125         start = round_down(phys_initrd_start, PAGE_SIZE);
126         size = phys_initrd_size + (phys_initrd_start - start);
127         size = round_up(size, PAGE_SIZE);
128
129         if (!memblock_is_region_memory(start, size)) {
130                 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
131                        (u64)start, size);
132                 goto disable;
133         }
134
135         if (memblock_is_region_reserved(start, size)) {
136                 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
137                        (u64)start, size);
138                 goto disable;
139         }
140
141         memblock_reserve(start, size);
142         /* Now convert initrd to virtual addresses */
143         initrd_start = (unsigned long)__va(phys_initrd_start);
144         initrd_end = initrd_start + phys_initrd_size;
145         initrd_below_start_ok = 1;
146
147         pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
148                 (void *)(initrd_start), size);
149         return;
150 disable:
151         pr_cont(" - disabling initrd\n");
152         initrd_start = 0;
153         initrd_end = 0;
154 }
155 #endif /* CONFIG_BLK_DEV_INITRD */
156
157 void __init setup_bootmem(void)
158 {
159         phys_addr_t mem_start = 0;
160         phys_addr_t start, end = 0;
161         phys_addr_t vmlinux_end = __pa_symbol(&_end);
162         phys_addr_t vmlinux_start = __pa_symbol(&_start);
163         u64 i;
164
165         /* Find the memory region containing the kernel */
166         for_each_mem_range(i, &start, &end) {
167                 phys_addr_t size = end - start;
168                 if (!mem_start)
169                         mem_start = start;
170                 if (start <= vmlinux_start && vmlinux_end <= end)
171                         BUG_ON(size == 0);
172         }
173
174         /*
175          * The maximal physical memory size is -PAGE_OFFSET.
176          * Make sure that any memory beyond mem_start + (-PAGE_OFFSET) is removed
177          * as it is unusable by kernel.
178          */
179         memblock_enforce_memory_limit(mem_start - PAGE_OFFSET);
180
181         /* Reserve from the start of the kernel to the end of the kernel */
182         memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
183
184         max_pfn = PFN_DOWN(memblock_end_of_DRAM());
185         max_low_pfn = max_pfn;
186         dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
187         set_max_mapnr(max_low_pfn);
188
189 #ifdef CONFIG_BLK_DEV_INITRD
190         setup_initrd();
191 #endif /* CONFIG_BLK_DEV_INITRD */
192
193         /*
194          * Avoid using early_init_fdt_reserve_self() since __pa() does
195          * not work for DTB pointers that are fixmap addresses
196          */
197         memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
198
199         early_init_fdt_scan_reserved_mem();
200         dma_contiguous_reserve(dma32_phys_limit);
201         memblock_allow_resize();
202         memblock_dump_all();
203 }
204
205 #ifdef CONFIG_MMU
206 static struct pt_alloc_ops pt_ops;
207
208 unsigned long va_pa_offset;
209 EXPORT_SYMBOL(va_pa_offset);
210 unsigned long pfn_base;
211 EXPORT_SYMBOL(pfn_base);
212
213 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
214 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
215 pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
216
217 #define MAX_EARLY_MAPPING_SIZE  SZ_128M
218
219 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
220
221 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
222 {
223         unsigned long addr = __fix_to_virt(idx);
224         pte_t *ptep;
225
226         BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
227
228         ptep = &fixmap_pte[pte_index(addr)];
229
230         if (pgprot_val(prot))
231                 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
232         else
233                 pte_clear(&init_mm, addr, ptep);
234         local_flush_tlb_page(addr);
235 }
236
237 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
238 {
239         return (pte_t *)((uintptr_t)pa);
240 }
241
242 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
243 {
244         clear_fixmap(FIX_PTE);
245         return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
246 }
247
248 static inline pte_t *get_pte_virt_late(phys_addr_t pa)
249 {
250         return (pte_t *) __va(pa);
251 }
252
253 static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
254 {
255         /*
256          * We only create PMD or PGD early mappings so we
257          * should never reach here with MMU disabled.
258          */
259         BUG();
260 }
261
262 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
263 {
264         return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
265 }
266
267 static phys_addr_t alloc_pte_late(uintptr_t va)
268 {
269         unsigned long vaddr;
270
271         vaddr = __get_free_page(GFP_KERNEL);
272         if (!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)))
273                 BUG();
274         return __pa(vaddr);
275 }
276
277 static void __init create_pte_mapping(pte_t *ptep,
278                                       uintptr_t va, phys_addr_t pa,
279                                       phys_addr_t sz, pgprot_t prot)
280 {
281         uintptr_t pte_idx = pte_index(va);
282
283         BUG_ON(sz != PAGE_SIZE);
284
285         if (pte_none(ptep[pte_idx]))
286                 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
287 }
288
289 #ifndef __PAGETABLE_PMD_FOLDED
290
291 pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
292 pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
293
294 #if MAX_EARLY_MAPPING_SIZE < PGDIR_SIZE
295 #define NUM_EARLY_PMDS          1UL
296 #else
297 #define NUM_EARLY_PMDS          (1UL + MAX_EARLY_MAPPING_SIZE / PGDIR_SIZE)
298 #endif
299 pmd_t early_pmd[PTRS_PER_PMD * NUM_EARLY_PMDS] __initdata __aligned(PAGE_SIZE);
300 pmd_t early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
301
302 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
303 {
304         /* Before MMU is enabled */
305         return (pmd_t *)((uintptr_t)pa);
306 }
307
308 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
309 {
310         clear_fixmap(FIX_PMD);
311         return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
312 }
313
314 static pmd_t *get_pmd_virt_late(phys_addr_t pa)
315 {
316         return (pmd_t *) __va(pa);
317 }
318
319 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
320 {
321         uintptr_t pmd_num;
322
323         pmd_num = (va - PAGE_OFFSET) >> PGDIR_SHIFT;
324         BUG_ON(pmd_num >= NUM_EARLY_PMDS);
325         return (uintptr_t)&early_pmd[pmd_num * PTRS_PER_PMD];
326 }
327
328 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
329 {
330         return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
331 }
332
333 static phys_addr_t alloc_pmd_late(uintptr_t va)
334 {
335         unsigned long vaddr;
336
337         vaddr = __get_free_page(GFP_KERNEL);
338         BUG_ON(!vaddr);
339         return __pa(vaddr);
340 }
341
342 static void __init create_pmd_mapping(pmd_t *pmdp,
343                                       uintptr_t va, phys_addr_t pa,
344                                       phys_addr_t sz, pgprot_t prot)
345 {
346         pte_t *ptep;
347         phys_addr_t pte_phys;
348         uintptr_t pmd_idx = pmd_index(va);
349
350         if (sz == PMD_SIZE) {
351                 if (pmd_none(pmdp[pmd_idx]))
352                         pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
353                 return;
354         }
355
356         if (pmd_none(pmdp[pmd_idx])) {
357                 pte_phys = pt_ops.alloc_pte(va);
358                 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
359                 ptep = pt_ops.get_pte_virt(pte_phys);
360                 memset(ptep, 0, PAGE_SIZE);
361         } else {
362                 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
363                 ptep = pt_ops.get_pte_virt(pte_phys);
364         }
365
366         create_pte_mapping(ptep, va, pa, sz, prot);
367 }
368
369 #define pgd_next_t              pmd_t
370 #define alloc_pgd_next(__va)    pt_ops.alloc_pmd(__va)
371 #define get_pgd_next_virt(__pa) pt_ops.get_pmd_virt(__pa)
372 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)      \
373         create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
374 #define fixmap_pgd_next         fixmap_pmd
375 #else
376 #define pgd_next_t              pte_t
377 #define alloc_pgd_next(__va)    pt_ops.alloc_pte(__va)
378 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
379 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)      \
380         create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
381 #define fixmap_pgd_next         fixmap_pte
382 #endif
383
384 void __init create_pgd_mapping(pgd_t *pgdp,
385                                       uintptr_t va, phys_addr_t pa,
386                                       phys_addr_t sz, pgprot_t prot)
387 {
388         pgd_next_t *nextp;
389         phys_addr_t next_phys;
390         uintptr_t pgd_idx = pgd_index(va);
391
392         if (sz == PGDIR_SIZE) {
393                 if (pgd_val(pgdp[pgd_idx]) == 0)
394                         pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
395                 return;
396         }
397
398         if (pgd_val(pgdp[pgd_idx]) == 0) {
399                 next_phys = alloc_pgd_next(va);
400                 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
401                 nextp = get_pgd_next_virt(next_phys);
402                 memset(nextp, 0, PAGE_SIZE);
403         } else {
404                 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
405                 nextp = get_pgd_next_virt(next_phys);
406         }
407
408         create_pgd_next_mapping(nextp, va, pa, sz, prot);
409 }
410
411 static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size)
412 {
413         /* Upgrade to PMD_SIZE mappings whenever possible */
414         if ((base & (PMD_SIZE - 1)) || (size & (PMD_SIZE - 1)))
415                 return PAGE_SIZE;
416
417         return PMD_SIZE;
418 }
419
420 /*
421  * setup_vm() is called from head.S with MMU-off.
422  *
423  * Following requirements should be honoured for setup_vm() to work
424  * correctly:
425  * 1) It should use PC-relative addressing for accessing kernel symbols.
426  *    To achieve this we always use GCC cmodel=medany.
427  * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
428  *    so disable compiler instrumentation when FTRACE is enabled.
429  *
430  * Currently, the above requirements are honoured by using custom CFLAGS
431  * for init.o in mm/Makefile.
432  */
433
434 #ifndef __riscv_cmodel_medany
435 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
436 #endif
437
438 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
439 {
440         uintptr_t va, pa, end_va;
441         uintptr_t load_pa = (uintptr_t)(&_start);
442         uintptr_t load_sz = (uintptr_t)(&_end) - load_pa;
443         uintptr_t map_size = best_map_size(load_pa, MAX_EARLY_MAPPING_SIZE);
444 #ifndef __PAGETABLE_PMD_FOLDED
445         pmd_t fix_bmap_spmd, fix_bmap_epmd;
446 #endif
447
448         va_pa_offset = PAGE_OFFSET - load_pa;
449         pfn_base = PFN_DOWN(load_pa);
450
451         /*
452          * Enforce boot alignment requirements of RV32 and
453          * RV64 by only allowing PMD or PGD mappings.
454          */
455         BUG_ON(map_size == PAGE_SIZE);
456
457         /* Sanity check alignment and size */
458         BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
459         BUG_ON((load_pa % map_size) != 0);
460         BUG_ON(load_sz > MAX_EARLY_MAPPING_SIZE);
461
462         pt_ops.alloc_pte = alloc_pte_early;
463         pt_ops.get_pte_virt = get_pte_virt_early;
464 #ifndef __PAGETABLE_PMD_FOLDED
465         pt_ops.alloc_pmd = alloc_pmd_early;
466         pt_ops.get_pmd_virt = get_pmd_virt_early;
467 #endif
468         /* Setup early PGD for fixmap */
469         create_pgd_mapping(early_pg_dir, FIXADDR_START,
470                            (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
471
472 #ifndef __PAGETABLE_PMD_FOLDED
473         /* Setup fixmap PMD */
474         create_pmd_mapping(fixmap_pmd, FIXADDR_START,
475                            (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
476         /* Setup trampoline PGD and PMD */
477         create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
478                            (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
479         create_pmd_mapping(trampoline_pmd, PAGE_OFFSET,
480                            load_pa, PMD_SIZE, PAGE_KERNEL_EXEC);
481 #else
482         /* Setup trampoline PGD */
483         create_pgd_mapping(trampoline_pg_dir, PAGE_OFFSET,
484                            load_pa, PGDIR_SIZE, PAGE_KERNEL_EXEC);
485 #endif
486
487         /*
488          * Setup early PGD covering entire kernel which will allows
489          * us to reach paging_init(). We map all memory banks later
490          * in setup_vm_final() below.
491          */
492         end_va = PAGE_OFFSET + load_sz;
493         for (va = PAGE_OFFSET; va < end_va; va += map_size)
494                 create_pgd_mapping(early_pg_dir, va,
495                                    load_pa + (va - PAGE_OFFSET),
496                                    map_size, PAGE_KERNEL_EXEC);
497
498 #ifndef __PAGETABLE_PMD_FOLDED
499         /* Setup early PMD for DTB */
500         create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
501                            (uintptr_t)early_dtb_pmd, PGDIR_SIZE, PAGE_TABLE);
502         /* Create two consecutive PMD mappings for FDT early scan */
503         pa = dtb_pa & ~(PMD_SIZE - 1);
504         create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA,
505                            pa, PMD_SIZE, PAGE_KERNEL);
506         create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA + PMD_SIZE,
507                            pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
508         dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PMD_SIZE - 1));
509 #else
510         /* Create two consecutive PGD mappings for FDT early scan */
511         pa = dtb_pa & ~(PGDIR_SIZE - 1);
512         create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
513                            pa, PGDIR_SIZE, PAGE_KERNEL);
514         create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA + PGDIR_SIZE,
515                            pa + PGDIR_SIZE, PGDIR_SIZE, PAGE_KERNEL);
516         dtb_early_va = (void *)DTB_EARLY_BASE_VA + (dtb_pa & (PGDIR_SIZE - 1));
517 #endif
518         dtb_early_pa = dtb_pa;
519
520         /*
521          * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
522          * range can not span multiple pmds.
523          */
524         BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
525                      != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
526
527 #ifndef __PAGETABLE_PMD_FOLDED
528         /*
529          * Early ioremap fixmap is already created as it lies within first 2MB
530          * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
531          * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
532          * the user if not.
533          */
534         fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
535         fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
536         if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
537                 WARN_ON(1);
538                 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
539                         pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
540                 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
541                         fix_to_virt(FIX_BTMAP_BEGIN));
542                 pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
543                         fix_to_virt(FIX_BTMAP_END));
544
545                 pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
546                 pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
547         }
548 #endif
549 }
550
551 static void __init setup_vm_final(void)
552 {
553         uintptr_t va, map_size;
554         phys_addr_t pa, start, end;
555         u64 i;
556
557         /**
558          * MMU is enabled at this point. But page table setup is not complete yet.
559          * fixmap page table alloc functions should be used at this point
560          */
561         pt_ops.alloc_pte = alloc_pte_fixmap;
562         pt_ops.get_pte_virt = get_pte_virt_fixmap;
563 #ifndef __PAGETABLE_PMD_FOLDED
564         pt_ops.alloc_pmd = alloc_pmd_fixmap;
565         pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
566 #endif
567         /* Setup swapper PGD for fixmap */
568         create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
569                            __pa_symbol(fixmap_pgd_next),
570                            PGDIR_SIZE, PAGE_TABLE);
571
572         /* Map all memory banks */
573         for_each_mem_range(i, &start, &end) {
574                 if (start >= end)
575                         break;
576                 if (start <= __pa(PAGE_OFFSET) &&
577                     __pa(PAGE_OFFSET) < end)
578                         start = __pa(PAGE_OFFSET);
579
580                 map_size = best_map_size(start, end - start);
581                 for (pa = start; pa < end; pa += map_size) {
582                         va = (uintptr_t)__va(pa);
583                         create_pgd_mapping(swapper_pg_dir, va, pa,
584                                            map_size, PAGE_KERNEL_EXEC);
585                 }
586         }
587
588         /* Clear fixmap PTE and PMD mappings */
589         clear_fixmap(FIX_PTE);
590         clear_fixmap(FIX_PMD);
591
592         /* Move to swapper page table */
593         csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
594         local_flush_tlb_all();
595
596         /* generic page allocation functions must be used to setup page table */
597         pt_ops.alloc_pte = alloc_pte_late;
598         pt_ops.get_pte_virt = get_pte_virt_late;
599 #ifndef __PAGETABLE_PMD_FOLDED
600         pt_ops.alloc_pmd = alloc_pmd_late;
601         pt_ops.get_pmd_virt = get_pmd_virt_late;
602 #endif
603 }
604 #else
605 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
606 {
607 #ifdef CONFIG_BUILTIN_DTB
608         dtb_early_va = soc_lookup_builtin_dtb();
609         if (!dtb_early_va) {
610                 /* Fallback to first available DTS */
611                 dtb_early_va = (void *) __dtb_start;
612         }
613 #else
614         dtb_early_va = (void *)dtb_pa;
615 #endif
616         dtb_early_pa = dtb_pa;
617 }
618
619 static inline void setup_vm_final(void)
620 {
621 }
622 #endif /* CONFIG_MMU */
623
624 #ifdef CONFIG_STRICT_KERNEL_RWX
625 void protect_kernel_text_data(void)
626 {
627         unsigned long text_start = (unsigned long)_start;
628         unsigned long init_text_start = (unsigned long)__init_text_begin;
629         unsigned long init_data_start = (unsigned long)__init_data_begin;
630         unsigned long rodata_start = (unsigned long)__start_rodata;
631         unsigned long data_start = (unsigned long)_data;
632         unsigned long max_low = (unsigned long)(__va(PFN_PHYS(max_low_pfn)));
633
634         set_memory_ro(text_start, (init_text_start - text_start) >> PAGE_SHIFT);
635         set_memory_ro(init_text_start, (init_data_start - init_text_start) >> PAGE_SHIFT);
636         set_memory_nx(init_data_start, (rodata_start - init_data_start) >> PAGE_SHIFT);
637         /* rodata section is marked readonly in mark_rodata_ro */
638         set_memory_nx(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
639         set_memory_nx(data_start, (max_low - data_start) >> PAGE_SHIFT);
640 }
641
642 void mark_rodata_ro(void)
643 {
644         unsigned long rodata_start = (unsigned long)__start_rodata;
645         unsigned long data_start = (unsigned long)_data;
646
647         set_memory_ro(rodata_start, (data_start - rodata_start) >> PAGE_SHIFT);
648
649         debug_checkwx();
650 }
651 #endif
652
653 void __init paging_init(void)
654 {
655         setup_vm_final();
656         sparse_init();
657         setup_zero_page();
658         zone_sizes_init();
659 }
660
661 #ifdef CONFIG_SPARSEMEM_VMEMMAP
662 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
663                                struct vmem_altmap *altmap)
664 {
665         return vmemmap_populate_basepages(start, end, node, NULL);
666 }
667 #endif