1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Based on arch/arm/mm/ioremap.c
4 *
5 * (C) Copyright 1995 1996 Linus Torvalds
6 * Hacked for ARM by Phil Blundell <philb@gnu.org>
7 * Hacked to allow all architectures to build, and various cleanups
8 * by Russell King
9 * Copyright (C) 2012 ARM Ltd.
10 */
11
12 #include <linux/export.h>
13 #include <linux/mm.h>
14 #include <linux/vmalloc.h>
15 #include <linux/io.h>
16
17 #include <asm/fixmap.h>
18 #include <asm/tlbflush.h>
19
__ioremap_caller(phys_addr_t phys_addr,size_t size,pgprot_t prot,void * caller)20 static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
21 pgprot_t prot, void *caller)
22 {
23 unsigned long last_addr;
24 unsigned long offset = phys_addr & ~PAGE_MASK;
25 int err;
26 unsigned long addr;
27 struct vm_struct *area;
28
29 /*
30 * Page align the mapping address and size, taking account of any
31 * offset.
32 */
33 phys_addr &= PAGE_MASK;
34 size = PAGE_ALIGN(size + offset);
35
36 /*
37 * Don't allow wraparound, zero size or outside PHYS_MASK.
38 */
39 last_addr = phys_addr + size - 1;
40 if (!size || last_addr < phys_addr || (last_addr & ~PHYS_MASK))
41 return NULL;
42
43 /*
44 * Don't allow RAM to be mapped.
45 */
46 if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr))))
47 return NULL;
48
49 area = get_vm_area_caller(size, VM_IOREMAP, caller);
50 if (!area)
51 return NULL;
52 addr = (unsigned long)area->addr;
53 area->phys_addr = phys_addr;
54
55 err = ioremap_page_range(addr, addr + size, phys_addr, prot);
56 if (err) {
57 vunmap((void *)addr);
58 return NULL;
59 }
60
61 return (void __iomem *)(offset + addr);
62 }
63
__ioremap(phys_addr_t phys_addr,size_t size,pgprot_t prot)64 void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot)
65 {
66 return __ioremap_caller(phys_addr, size, prot,
67 __builtin_return_address(0));
68 }
69 EXPORT_SYMBOL(__ioremap);
70
iounmap(volatile void __iomem * io_addr)71 void iounmap(volatile void __iomem *io_addr)
72 {
73 unsigned long addr = (unsigned long)io_addr & PAGE_MASK;
74
75 /*
76 * We could get an address outside vmalloc range in case
77 * of ioremap_cache() reusing a RAM mapping.
78 */
79 if (is_vmalloc_addr((void *)addr))
80 vunmap((void *)addr);
81 }
82 EXPORT_SYMBOL(iounmap);
83
ioremap_cache(phys_addr_t phys_addr,size_t size)84 void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size)
85 {
86 /* For normal memory we already have a cacheable mapping. */
87 if (pfn_valid(__phys_to_pfn(phys_addr)))
88 return (void __iomem *)__phys_to_virt(phys_addr);
89
90 return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL),
91 __builtin_return_address(0));
92 }
93 EXPORT_SYMBOL(ioremap_cache);
94
95 /*
96 * Must be called after early_fixmap_init
97 */
early_ioremap_init(void)98 void __init early_ioremap_init(void)
99 {
100 early_ioremap_setup();
101 }
102
