1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2012 Regents of the University of California
4 * Copyright (C) 2019 Western Digital Corporation or its affiliates.
7 #include <linux/init.h>
9 #include <linux/memblock.h>
10 #include <linux/initrd.h>
11 #include <linux/swap.h>
12 #include <linux/sizes.h>
13 #include <linux/of_fdt.h>
14 #include <linux/libfdt.h>
15 #include <linux/set_memory.h>
17 #include <asm/fixmap.h>
18 #include <asm/tlbflush.h>
19 #include <asm/sections.h>
22 #include <asm/ptdump.h>
24 #include "../kernel/head.h"
26 unsigned long empty_zero_page
[PAGE_SIZE
/ sizeof(unsigned long)]
28 EXPORT_SYMBOL(empty_zero_page
);
33 static void __init
zone_sizes_init(void)
35 unsigned long max_zone_pfns
[MAX_NR_ZONES
] = { 0, };
37 #ifdef CONFIG_ZONE_DMA32
38 max_zone_pfns
[ZONE_DMA32
] = PFN_DOWN(min(4UL * SZ_1G
,
39 (unsigned long) PFN_PHYS(max_low_pfn
)));
41 max_zone_pfns
[ZONE_NORMAL
] = max_low_pfn
;
43 free_area_init(max_zone_pfns
);
46 static void setup_zero_page(void)
48 memset((void *)empty_zero_page
, 0, PAGE_SIZE
);
51 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
52 static inline void print_mlk(char *name
, unsigned long b
, unsigned long t
)
54 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name
, b
, t
,
58 static inline void print_mlm(char *name
, unsigned long b
, unsigned long t
)
60 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name
, b
, t
,
64 static void print_vm_layout(void)
66 pr_notice("Virtual kernel memory layout:\n");
67 print_mlk("fixmap", (unsigned long)FIXADDR_START
,
68 (unsigned long)FIXADDR_TOP
);
69 print_mlm("pci io", (unsigned long)PCI_IO_START
,
70 (unsigned long)PCI_IO_END
);
71 print_mlm("vmemmap", (unsigned long)VMEMMAP_START
,
72 (unsigned long)VMEMMAP_END
);
73 print_mlm("vmalloc", (unsigned long)VMALLOC_START
,
74 (unsigned long)VMALLOC_END
);
75 print_mlm("lowmem", (unsigned long)PAGE_OFFSET
,
76 (unsigned long)high_memory
);
79 static void print_vm_layout(void) { }
80 #endif /* CONFIG_DEBUG_VM */
82 void __init
mem_init(void)
86 #endif /* CONFIG_FLATMEM */
88 high_memory
= (void *)(__va(PFN_PHYS(max_low_pfn
)));
91 mem_init_print_info(NULL
);
95 #ifdef CONFIG_BLK_DEV_INITRD
96 static void __init
setup_initrd(void)
101 /* Ignore the virtul address computed during device tree parsing */
102 initrd_start
= initrd_end
= 0;
104 if (!phys_initrd_size
)
107 * Round the memory region to page boundaries as per free_initrd_mem()
108 * This allows us to detect whether the pages overlapping the initrd
109 * are in use, but more importantly, reserves the entire set of pages
110 * as we don't want these pages allocated for other purposes.
112 start
= round_down(phys_initrd_start
, PAGE_SIZE
);
113 size
= phys_initrd_size
+ (phys_initrd_start
- start
);
114 size
= round_up(size
, PAGE_SIZE
);
116 if (!memblock_is_region_memory(start
, size
)) {
117 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
122 if (memblock_is_region_reserved(start
, size
)) {
123 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
128 memblock_reserve(start
, size
);
129 /* Now convert initrd to virtual addresses */
130 initrd_start
= (unsigned long)__va(phys_initrd_start
);
131 initrd_end
= initrd_start
+ phys_initrd_size
;
132 initrd_below_start_ok
= 1;
134 pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
135 (void *)(initrd_start
), size
);
138 pr_cont(" - disabling initrd\n");
142 #endif /* CONFIG_BLK_DEV_INITRD */
144 static phys_addr_t dtb_early_pa __initdata
;
146 void __init
setup_bootmem(void)
148 struct memblock_region
*reg
;
149 phys_addr_t mem_size
= 0;
150 phys_addr_t total_mem
= 0;
151 phys_addr_t mem_start
, end
= 0;
152 phys_addr_t vmlinux_end
= __pa_symbol(&_end
);
153 phys_addr_t vmlinux_start
= __pa_symbol(&_start
);
155 /* Find the memory region containing the kernel */
156 for_each_memblock(memory
, reg
) {
157 end
= reg
->base
+ reg
->size
;
159 mem_start
= reg
->base
;
160 if (reg
->base
<= vmlinux_start
&& vmlinux_end
<= end
)
161 BUG_ON(reg
->size
== 0);
162 total_mem
= total_mem
+ reg
->size
;
166 * Remove memblock from the end of usable area to the
169 mem_size
= min(total_mem
, (phys_addr_t
)-PAGE_OFFSET
);
170 if (mem_start
+ mem_size
< end
)
171 memblock_remove(mem_start
+ mem_size
,
172 end
- mem_start
- mem_size
);
174 /* Reserve from the start of the kernel to the end of the kernel */
175 memblock_reserve(vmlinux_start
, vmlinux_end
- vmlinux_start
);
177 max_pfn
= PFN_DOWN(memblock_end_of_DRAM());
178 max_low_pfn
= max_pfn
;
179 set_max_mapnr(max_low_pfn
);
181 #ifdef CONFIG_BLK_DEV_INITRD
183 #endif /* CONFIG_BLK_DEV_INITRD */
186 * Avoid using early_init_fdt_reserve_self() since __pa() does
187 * not work for DTB pointers that are fixmap addresses
189 memblock_reserve(dtb_early_pa
, fdt_totalsize(dtb_early_va
));
191 early_init_fdt_scan_reserved_mem();
192 memblock_allow_resize();
195 for_each_memblock(memory
, reg
) {
196 unsigned long start_pfn
= memblock_region_memory_base_pfn(reg
);
197 unsigned long end_pfn
= memblock_region_memory_end_pfn(reg
);
199 memblock_set_node(PFN_PHYS(start_pfn
),
200 PFN_PHYS(end_pfn
- start_pfn
),
201 &memblock
.memory
, 0);
206 unsigned long va_pa_offset
;
207 EXPORT_SYMBOL(va_pa_offset
);
208 unsigned long pfn_base
;
209 EXPORT_SYMBOL(pfn_base
);
211 pgd_t swapper_pg_dir
[PTRS_PER_PGD
] __page_aligned_bss
;
212 pgd_t trampoline_pg_dir
[PTRS_PER_PGD
] __page_aligned_bss
;
213 pte_t fixmap_pte
[PTRS_PER_PTE
] __page_aligned_bss
;
214 static bool mmu_enabled
;
216 #define MAX_EARLY_MAPPING_SIZE SZ_128M
218 pgd_t early_pg_dir
[PTRS_PER_PGD
] __initdata
__aligned(PAGE_SIZE
);
220 void __set_fixmap(enum fixed_addresses idx
, phys_addr_t phys
, pgprot_t prot
)
222 unsigned long addr
= __fix_to_virt(idx
);
225 BUG_ON(idx
<= FIX_HOLE
|| idx
>= __end_of_fixed_addresses
);
227 ptep
= &fixmap_pte
[pte_index(addr
)];
229 if (pgprot_val(prot
)) {
230 set_pte(ptep
, pfn_pte(phys
>> PAGE_SHIFT
, prot
));
232 pte_clear(&init_mm
, addr
, ptep
);
233 local_flush_tlb_page(addr
);
237 static pte_t
*__init
get_pte_virt(phys_addr_t pa
)
240 clear_fixmap(FIX_PTE
);
241 return (pte_t
*)set_fixmap_offset(FIX_PTE
, pa
);
243 return (pte_t
*)((uintptr_t)pa
);
247 static phys_addr_t __init
alloc_pte(uintptr_t va
)
250 * We only create PMD or PGD early mappings so we
251 * should never reach here with MMU disabled.
253 BUG_ON(!mmu_enabled
);
255 return memblock_phys_alloc(PAGE_SIZE
, PAGE_SIZE
);
258 static void __init
create_pte_mapping(pte_t
*ptep
,
259 uintptr_t va
, phys_addr_t pa
,
260 phys_addr_t sz
, pgprot_t prot
)
262 uintptr_t pte_idx
= pte_index(va
);
264 BUG_ON(sz
!= PAGE_SIZE
);
266 if (pte_none(ptep
[pte_idx
]))
267 ptep
[pte_idx
] = pfn_pte(PFN_DOWN(pa
), prot
);
270 #ifndef __PAGETABLE_PMD_FOLDED
272 pmd_t trampoline_pmd
[PTRS_PER_PMD
] __page_aligned_bss
;
273 pmd_t fixmap_pmd
[PTRS_PER_PMD
] __page_aligned_bss
;
275 #if MAX_EARLY_MAPPING_SIZE < PGDIR_SIZE
276 #define NUM_EARLY_PMDS 1UL
278 #define NUM_EARLY_PMDS (1UL + MAX_EARLY_MAPPING_SIZE / PGDIR_SIZE)
280 pmd_t early_pmd
[PTRS_PER_PMD
* NUM_EARLY_PMDS
] __initdata
__aligned(PAGE_SIZE
);
282 static pmd_t
*__init
get_pmd_virt(phys_addr_t pa
)
285 clear_fixmap(FIX_PMD
);
286 return (pmd_t
*)set_fixmap_offset(FIX_PMD
, pa
);
288 return (pmd_t
*)((uintptr_t)pa
);
292 static phys_addr_t __init
alloc_pmd(uintptr_t va
)
297 return memblock_phys_alloc(PAGE_SIZE
, PAGE_SIZE
);
299 pmd_num
= (va
- PAGE_OFFSET
) >> PGDIR_SHIFT
;
300 BUG_ON(pmd_num
>= NUM_EARLY_PMDS
);
301 return (uintptr_t)&early_pmd
[pmd_num
* PTRS_PER_PMD
];
304 static void __init
create_pmd_mapping(pmd_t
*pmdp
,
305 uintptr_t va
, phys_addr_t pa
,
306 phys_addr_t sz
, pgprot_t prot
)
309 phys_addr_t pte_phys
;
310 uintptr_t pmd_idx
= pmd_index(va
);
312 if (sz
== PMD_SIZE
) {
313 if (pmd_none(pmdp
[pmd_idx
]))
314 pmdp
[pmd_idx
] = pfn_pmd(PFN_DOWN(pa
), prot
);
318 if (pmd_none(pmdp
[pmd_idx
])) {
319 pte_phys
= alloc_pte(va
);
320 pmdp
[pmd_idx
] = pfn_pmd(PFN_DOWN(pte_phys
), PAGE_TABLE
);
321 ptep
= get_pte_virt(pte_phys
);
322 memset(ptep
, 0, PAGE_SIZE
);
324 pte_phys
= PFN_PHYS(_pmd_pfn(pmdp
[pmd_idx
]));
325 ptep
= get_pte_virt(pte_phys
);
328 create_pte_mapping(ptep
, va
, pa
, sz
, prot
);
331 #define pgd_next_t pmd_t
332 #define alloc_pgd_next(__va) alloc_pmd(__va)
333 #define get_pgd_next_virt(__pa) get_pmd_virt(__pa)
334 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
335 create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
336 #define fixmap_pgd_next fixmap_pmd
338 #define pgd_next_t pte_t
339 #define alloc_pgd_next(__va) alloc_pte(__va)
340 #define get_pgd_next_virt(__pa) get_pte_virt(__pa)
341 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
342 create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
343 #define fixmap_pgd_next fixmap_pte
346 static void __init
create_pgd_mapping(pgd_t
*pgdp
,
347 uintptr_t va
, phys_addr_t pa
,
348 phys_addr_t sz
, pgprot_t prot
)
351 phys_addr_t next_phys
;
352 uintptr_t pgd_idx
= pgd_index(va
);
354 if (sz
== PGDIR_SIZE
) {
355 if (pgd_val(pgdp
[pgd_idx
]) == 0)
356 pgdp
[pgd_idx
] = pfn_pgd(PFN_DOWN(pa
), prot
);
360 if (pgd_val(pgdp
[pgd_idx
]) == 0) {
361 next_phys
= alloc_pgd_next(va
);
362 pgdp
[pgd_idx
] = pfn_pgd(PFN_DOWN(next_phys
), PAGE_TABLE
);
363 nextp
= get_pgd_next_virt(next_phys
);
364 memset(nextp
, 0, PAGE_SIZE
);
366 next_phys
= PFN_PHYS(_pgd_pfn(pgdp
[pgd_idx
]));
367 nextp
= get_pgd_next_virt(next_phys
);
370 create_pgd_next_mapping(nextp
, va
, pa
, sz
, prot
);
373 static uintptr_t __init
best_map_size(phys_addr_t base
, phys_addr_t size
)
375 /* Upgrade to PMD_SIZE mappings whenever possible */
376 if ((base
& (PMD_SIZE
- 1)) || (size
& (PMD_SIZE
- 1)))
383 * setup_vm() is called from head.S with MMU-off.
385 * Following requirements should be honoured for setup_vm() to work
387 * 1) It should use PC-relative addressing for accessing kernel symbols.
388 * To achieve this we always use GCC cmodel=medany.
389 * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
390 * so disable compiler instrumentation when FTRACE is enabled.
392 * Currently, the above requirements are honoured by using custom CFLAGS
393 * for init.o in mm/Makefile.
396 #ifndef __riscv_cmodel_medany
397 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
400 asmlinkage
void __init
setup_vm(uintptr_t dtb_pa
)
402 uintptr_t va
, end_va
;
403 uintptr_t load_pa
= (uintptr_t)(&_start
);
404 uintptr_t load_sz
= (uintptr_t)(&_end
) - load_pa
;
405 uintptr_t map_size
= best_map_size(load_pa
, MAX_EARLY_MAPPING_SIZE
);
407 va_pa_offset
= PAGE_OFFSET
- load_pa
;
408 pfn_base
= PFN_DOWN(load_pa
);
411 * Enforce boot alignment requirements of RV32 and
412 * RV64 by only allowing PMD or PGD mappings.
414 BUG_ON(map_size
== PAGE_SIZE
);
416 /* Sanity check alignment and size */
417 BUG_ON((PAGE_OFFSET
% PGDIR_SIZE
) != 0);
418 BUG_ON((load_pa
% map_size
) != 0);
419 BUG_ON(load_sz
> MAX_EARLY_MAPPING_SIZE
);
421 /* Setup early PGD for fixmap */
422 create_pgd_mapping(early_pg_dir
, FIXADDR_START
,
423 (uintptr_t)fixmap_pgd_next
, PGDIR_SIZE
, PAGE_TABLE
);
425 #ifndef __PAGETABLE_PMD_FOLDED
426 /* Setup fixmap PMD */
427 create_pmd_mapping(fixmap_pmd
, FIXADDR_START
,
428 (uintptr_t)fixmap_pte
, PMD_SIZE
, PAGE_TABLE
);
429 /* Setup trampoline PGD and PMD */
430 create_pgd_mapping(trampoline_pg_dir
, PAGE_OFFSET
,
431 (uintptr_t)trampoline_pmd
, PGDIR_SIZE
, PAGE_TABLE
);
432 create_pmd_mapping(trampoline_pmd
, PAGE_OFFSET
,
433 load_pa
, PMD_SIZE
, PAGE_KERNEL_EXEC
);
435 /* Setup trampoline PGD */
436 create_pgd_mapping(trampoline_pg_dir
, PAGE_OFFSET
,
437 load_pa
, PGDIR_SIZE
, PAGE_KERNEL_EXEC
);
441 * Setup early PGD covering entire kernel which will allows
442 * us to reach paging_init(). We map all memory banks later
443 * in setup_vm_final() below.
445 end_va
= PAGE_OFFSET
+ load_sz
;
446 for (va
= PAGE_OFFSET
; va
< end_va
; va
+= map_size
)
447 create_pgd_mapping(early_pg_dir
, va
,
448 load_pa
+ (va
- PAGE_OFFSET
),
449 map_size
, PAGE_KERNEL_EXEC
);
451 /* Create fixed mapping for early FDT parsing */
452 end_va
= __fix_to_virt(FIX_FDT
) + FIX_FDT_SIZE
;
453 for (va
= __fix_to_virt(FIX_FDT
); va
< end_va
; va
+= PAGE_SIZE
)
454 create_pte_mapping(fixmap_pte
, va
,
455 dtb_pa
+ (va
- __fix_to_virt(FIX_FDT
)),
456 PAGE_SIZE
, PAGE_KERNEL
);
458 /* Save pointer to DTB for early FDT parsing */
459 dtb_early_va
= (void *)fix_to_virt(FIX_FDT
) + (dtb_pa
& ~PAGE_MASK
);
460 /* Save physical address for memblock reservation */
461 dtb_early_pa
= dtb_pa
;
464 static void __init
setup_vm_final(void)
466 uintptr_t va
, map_size
;
467 phys_addr_t pa
, start
, end
;
468 struct memblock_region
*reg
;
470 /* Set mmu_enabled flag */
473 /* Setup swapper PGD for fixmap */
474 create_pgd_mapping(swapper_pg_dir
, FIXADDR_START
,
475 __pa_symbol(fixmap_pgd_next
),
476 PGDIR_SIZE
, PAGE_TABLE
);
478 /* Map all memory banks */
479 for_each_memblock(memory
, reg
) {
481 end
= start
+ reg
->size
;
485 if (memblock_is_nomap(reg
))
487 if (start
<= __pa(PAGE_OFFSET
) &&
488 __pa(PAGE_OFFSET
) < end
)
489 start
= __pa(PAGE_OFFSET
);
491 map_size
= best_map_size(start
, end
- start
);
492 for (pa
= start
; pa
< end
; pa
+= map_size
) {
493 va
= (uintptr_t)__va(pa
);
494 create_pgd_mapping(swapper_pg_dir
, va
, pa
,
495 map_size
, PAGE_KERNEL_EXEC
);
499 /* Clear fixmap PTE and PMD mappings */
500 clear_fixmap(FIX_PTE
);
501 clear_fixmap(FIX_PMD
);
503 /* Move to swapper page table */
504 csr_write(CSR_SATP
, PFN_DOWN(__pa_symbol(swapper_pg_dir
)) | SATP_MODE
);
505 local_flush_tlb_all();
508 asmlinkage
void __init
setup_vm(uintptr_t dtb_pa
)
510 #ifdef CONFIG_BUILTIN_DTB
511 dtb_early_va
= soc_lookup_builtin_dtb();
513 /* Fallback to first available DTS */
514 dtb_early_va
= (void *) __dtb_start
;
517 dtb_early_va
= (void *)dtb_pa
;
521 static inline void setup_vm_final(void)
524 #endif /* CONFIG_MMU */
526 #ifdef CONFIG_STRICT_KERNEL_RWX
527 void mark_rodata_ro(void)
529 unsigned long text_start
= (unsigned long)_text
;
530 unsigned long text_end
= (unsigned long)_etext
;
531 unsigned long rodata_start
= (unsigned long)__start_rodata
;
532 unsigned long data_start
= (unsigned long)_data
;
533 unsigned long max_low
= (unsigned long)(__va(PFN_PHYS(max_low_pfn
)));
535 set_memory_ro(text_start
, (text_end
- text_start
) >> PAGE_SHIFT
);
536 set_memory_ro(rodata_start
, (data_start
- rodata_start
) >> PAGE_SHIFT
);
537 set_memory_nx(rodata_start
, (data_start
- rodata_start
) >> PAGE_SHIFT
);
538 set_memory_nx(data_start
, (max_low
- data_start
) >> PAGE_SHIFT
);
544 static void __init
resource_init(void)
546 struct memblock_region
*region
;
548 for_each_memblock(memory
, region
) {
549 struct resource
*res
;
551 res
= memblock_alloc(sizeof(struct resource
), SMP_CACHE_BYTES
);
553 panic("%s: Failed to allocate %zu bytes\n", __func__
,
554 sizeof(struct resource
));
556 if (memblock_is_nomap(region
)) {
557 res
->name
= "reserved";
558 res
->flags
= IORESOURCE_MEM
;
560 res
->name
= "System RAM";
561 res
->flags
= IORESOURCE_SYSTEM_RAM
| IORESOURCE_BUSY
;
563 res
->start
= __pfn_to_phys(memblock_region_memory_base_pfn(region
));
564 res
->end
= __pfn_to_phys(memblock_region_memory_end_pfn(region
)) - 1;
566 request_resource(&iomem_resource
, res
);
570 void __init
paging_init(void)
579 #ifdef CONFIG_SPARSEMEM_VMEMMAP
580 int __meminit
vmemmap_populate(unsigned long start
, unsigned long end
, int node
,
581 struct vmem_altmap
*altmap
)
583 return vmemmap_populate_basepages(start
, end
, node
, NULL
);