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author | 2025-03-08 22:04:20 +0800 | |
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committer | 2025-03-08 22:04:20 +0800 | |
commit | a07bb8fd1299070229f0e8f3dcb57ffd5ef9870a (patch) | |
tree | 84f21bd0bf7071bc5fc7dd989e77d7ceb5476682 /arch/mips/mm/ioremap.c | |
download | ohosKernel-a07bb8fd1299070229f0e8f3dcb57ffd5ef9870a.tar.gz ohosKernel-a07bb8fd1299070229f0e8f3dcb57ffd5ef9870a.zip |
Initial commit: OpenHarmony-v4.0-ReleaseOpenHarmony-v4.0-Release
Diffstat (limited to 'arch/mips/mm/ioremap.c')
-rw-r--r-- | arch/mips/mm/ioremap.c | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/arch/mips/mm/ioremap.c b/arch/mips/mm/ioremap.c new file mode 100644 index 000000000..b6dad2fd5 --- /dev/null +++ b/arch/mips/mm/ioremap.c | |||
@@ -0,0 +1,119 @@ | |||
1 | /* | ||
2 | * This file is subject to the terms and conditions of the GNU General Public | ||
3 | * License. See the file "COPYING" in the main directory of this archive | ||
4 | * for more details. | ||
5 | * | ||
6 | * (C) Copyright 1995 1996 Linus Torvalds | ||
7 | * (C) Copyright 2001, 2002 Ralf Baechle | ||
8 | */ | ||
9 | #include <linux/export.h> | ||
10 | #include <asm/addrspace.h> | ||
11 | #include <asm/byteorder.h> | ||
12 | #include <linux/ioport.h> | ||
13 | #include <linux/sched.h> | ||
14 | #include <linux/slab.h> | ||
15 | #include <linux/vmalloc.h> | ||
16 | #include <linux/mm_types.h> | ||
17 | #include <linux/io.h> | ||
18 | #include <asm/cacheflush.h> | ||
19 | #include <asm/tlbflush.h> | ||
20 | #include <ioremap.h> | ||
21 | |||
22 | #define IS_LOW512(addr) (!((phys_addr_t)(addr) & (phys_addr_t) ~0x1fffffffULL)) | ||
23 | #define IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == CKSEG1) | ||
24 | |||
25 | static int __ioremap_check_ram(unsigned long start_pfn, unsigned long nr_pages, | ||
26 | void *arg) | ||
27 | { | ||
28 | unsigned long i; | ||
29 | |||
30 | for (i = 0; i < nr_pages; i++) { | ||
31 | if (pfn_valid(start_pfn + i) && | ||
32 | !PageReserved(pfn_to_page(start_pfn + i))) | ||
33 | return 1; | ||
34 | } | ||
35 | |||
36 | return 0; | ||
37 | } | ||
38 | |||
39 | /* | ||
40 | * ioremap_prot - map bus memory into CPU space | ||
41 | * @phys_addr: bus address of the memory | ||
42 | * @size: size of the resource to map | ||
43 | * | ||
44 | * ioremap_prot gives the caller control over cache coherency attributes (CCA) | ||
45 | */ | ||
46 | void __iomem *ioremap_prot(phys_addr_t phys_addr, unsigned long size, | ||
47 | unsigned long prot_val) | ||
48 | { | ||
49 | unsigned long flags = prot_val & _CACHE_MASK; | ||
50 | unsigned long offset, pfn, last_pfn; | ||
51 | struct vm_struct *area; | ||
52 | phys_addr_t last_addr; | ||
53 | unsigned long vaddr; | ||
54 | void __iomem *cpu_addr; | ||
55 | |||
56 | cpu_addr = plat_ioremap(phys_addr, size, flags); | ||
57 | if (cpu_addr) | ||
58 | return cpu_addr; | ||
59 | |||
60 | phys_addr = fixup_bigphys_addr(phys_addr, size); | ||
61 | |||
62 | /* Don't allow wraparound or zero size */ | ||
63 | last_addr = phys_addr + size - 1; | ||
64 | if (!size || last_addr < phys_addr) | ||
65 | return NULL; | ||
66 | |||
67 | /* | ||
68 | * Map uncached objects in the low 512mb of address space using KSEG1, | ||
69 | * otherwise map using page tables. | ||
70 | */ | ||
71 | if (IS_LOW512(phys_addr) && IS_LOW512(last_addr) && | ||
72 | flags == _CACHE_UNCACHED) | ||
73 | return (void __iomem *) CKSEG1ADDR(phys_addr); | ||
74 | |||
75 | /* | ||
76 | * Don't allow anybody to remap RAM that may be allocated by the page | ||
77 | * allocator, since that could lead to races & data clobbering. | ||
78 | */ | ||
79 | pfn = PFN_DOWN(phys_addr); | ||
80 | last_pfn = PFN_DOWN(last_addr); | ||
81 | if (walk_system_ram_range(pfn, last_pfn - pfn + 1, NULL, | ||
82 | __ioremap_check_ram) == 1) { | ||
83 | WARN_ONCE(1, "ioremap on RAM at %pa - %pa\n", | ||
84 | &phys_addr, &last_addr); | ||
85 | return NULL; | ||
86 | } | ||
87 | |||
88 | /* | ||
89 | * Mappings have to be page-aligned | ||
90 | */ | ||
91 | offset = phys_addr & ~PAGE_MASK; | ||
92 | phys_addr &= PAGE_MASK; | ||
93 | size = PAGE_ALIGN(last_addr + 1) - phys_addr; | ||
94 | |||
95 | /* | ||
96 | * Ok, go for it.. | ||
97 | */ | ||
98 | area = get_vm_area(size, VM_IOREMAP); | ||
99 | if (!area) | ||
100 | return NULL; | ||
101 | vaddr = (unsigned long)area->addr; | ||
102 | |||
103 | flags |= _PAGE_GLOBAL | _PAGE_PRESENT | __READABLE | __WRITEABLE; | ||
104 | if (ioremap_page_range(vaddr, vaddr + size, phys_addr, | ||
105 | __pgprot(flags))) { | ||
106 | free_vm_area(area); | ||
107 | return NULL; | ||
108 | } | ||
109 | |||
110 | return (void __iomem *)(vaddr + offset); | ||
111 | } | ||
112 | EXPORT_SYMBOL(ioremap_prot); | ||
113 | |||
114 | void iounmap(const volatile void __iomem *addr) | ||
115 | { | ||
116 | if (!plat_iounmap(addr) && !IS_KSEG1(addr)) | ||
117 | vunmap((void *)((unsigned long)addr & PAGE_MASK)); | ||
118 | } | ||
119 | EXPORT_SYMBOL(iounmap); | ||