1 /* SPDX-License-Identifier: GPL-2.0 */ 1 /* SPDX-License-Identifier: GPL-2.0 */
2 #include <linux/device.h> 2 #include <linux/device.h>
3 #include <linux/types.h> 3 #include <linux/types.h>
4 #include <linux/io.h> 4 #include <linux/io.h>
5 #include <linux/mm.h> 5 #include <linux/mm.h>
6 #include <linux/ioremap.h> !! 6
>> 7 #ifndef ioremap_cache
>> 8 /* temporary while we convert existing ioremap_cache users to memremap */
>> 9 __weak void __iomem *ioremap_cache(resource_size_t offset, unsigned long size)
>> 10 {
>> 11 return ioremap(offset, size);
>> 12 }
>> 13 #endif
7 14
8 #ifndef arch_memremap_wb 15 #ifndef arch_memremap_wb
9 static void *arch_memremap_wb(resource_size_t 16 static void *arch_memremap_wb(resource_size_t offset, unsigned long size)
10 { 17 {
11 #ifdef ioremap_cache <<
12 return (__force void *)ioremap_cache(o 18 return (__force void *)ioremap_cache(offset, size);
13 #else <<
14 return (__force void *)ioremap(offset, <<
15 #endif <<
16 } 19 }
17 #endif 20 #endif
18 21
19 #ifndef arch_memremap_can_ram_remap 22 #ifndef arch_memremap_can_ram_remap
20 static bool arch_memremap_can_ram_remap(resour 23 static bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
21 unsign 24 unsigned long flags)
22 { 25 {
23 return true; 26 return true;
24 } 27 }
25 #endif 28 #endif
26 29
27 static void *try_ram_remap(resource_size_t off 30 static void *try_ram_remap(resource_size_t offset, size_t size,
28 unsigned long flags 31 unsigned long flags)
29 { 32 {
30 unsigned long pfn = PHYS_PFN(offset); 33 unsigned long pfn = PHYS_PFN(offset);
31 34
32 /* In the simple case just return the 35 /* In the simple case just return the existing linear address */
33 if (pfn_valid(pfn) && !PageHighMem(pfn 36 if (pfn_valid(pfn) && !PageHighMem(pfn_to_page(pfn)) &&
34 arch_memremap_can_ram_remap(offset 37 arch_memremap_can_ram_remap(offset, size, flags))
35 return __va(offset); 38 return __va(offset);
36 39
37 return NULL; /* fallback to arch_memre 40 return NULL; /* fallback to arch_memremap_wb */
38 } 41 }
39 42
40 /** 43 /**
41 * memremap() - remap an iomem_resource as cac 44 * memremap() - remap an iomem_resource as cacheable memory
42 * @offset: iomem resource start address 45 * @offset: iomem resource start address
43 * @size: size of remap 46 * @size: size of remap
44 * @flags: any of MEMREMAP_WB, MEMREMAP_WT, ME 47 * @flags: any of MEMREMAP_WB, MEMREMAP_WT, MEMREMAP_WC,
45 * MEMREMAP_ENC, MEMREMAP_DEC 48 * MEMREMAP_ENC, MEMREMAP_DEC
46 * 49 *
47 * memremap() is "ioremap" for cases where it 50 * memremap() is "ioremap" for cases where it is known that the resource
48 * being mapped does not have i/o side effects 51 * being mapped does not have i/o side effects and the __iomem
49 * annotation is not applicable. In the case o 52 * annotation is not applicable. In the case of multiple flags, the different
50 * mapping types will be attempted in the orde 53 * mapping types will be attempted in the order listed below until one of
51 * them succeeds. 54 * them succeeds.
52 * 55 *
53 * MEMREMAP_WB - matches the default mapping f 56 * MEMREMAP_WB - matches the default mapping for System RAM on
54 * the architecture. This is usually a read-a 57 * the architecture. This is usually a read-allocate write-back cache.
55 * Moreover, if MEMREMAP_WB is specified and t 58 * Moreover, if MEMREMAP_WB is specified and the requested remap region is RAM
56 * memremap() will bypass establishing a new m 59 * memremap() will bypass establishing a new mapping and instead return
57 * a pointer into the direct map. 60 * a pointer into the direct map.
58 * 61 *
59 * MEMREMAP_WT - establish a mapping whereby w 62 * MEMREMAP_WT - establish a mapping whereby writes either bypass the
60 * cache or are written through to memory and 63 * cache or are written through to memory and never exist in a
61 * cache-dirty state with respect to program v 64 * cache-dirty state with respect to program visibility. Attempts to
62 * map System RAM with this mapping type will 65 * map System RAM with this mapping type will fail.
63 * 66 *
64 * MEMREMAP_WC - establish a writecombine mapp 67 * MEMREMAP_WC - establish a writecombine mapping, whereby writes may
65 * be coalesced together (e.g. in the CPU's wr 68 * be coalesced together (e.g. in the CPU's write buffers), but is otherwise
66 * uncached. Attempts to map System RAM with t 69 * uncached. Attempts to map System RAM with this mapping type will fail.
67 */ 70 */
68 void *memremap(resource_size_t offset, size_t 71 void *memremap(resource_size_t offset, size_t size, unsigned long flags)
69 { 72 {
70 int is_ram = region_intersects(offset, 73 int is_ram = region_intersects(offset, size,
71 IORESOU 74 IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
72 void *addr = NULL; 75 void *addr = NULL;
73 76
74 if (!flags) 77 if (!flags)
75 return NULL; 78 return NULL;
76 79
77 if (is_ram == REGION_MIXED) { 80 if (is_ram == REGION_MIXED) {
78 WARN_ONCE(1, "memremap attempt 81 WARN_ONCE(1, "memremap attempted on mixed range %pa size: %#lx\n",
79 &offset, (unsi 82 &offset, (unsigned long) size);
80 return NULL; 83 return NULL;
81 } 84 }
82 85
83 /* Try all mapping types requested unt 86 /* Try all mapping types requested until one returns non-NULL */
84 if (flags & MEMREMAP_WB) { 87 if (flags & MEMREMAP_WB) {
85 /* 88 /*
86 * MEMREMAP_WB is special in t 89 * MEMREMAP_WB is special in that it can be satisfied
87 * from the direct map. Some 90 * from the direct map. Some archs depend on the
88 * capability of memremap() to 91 * capability of memremap() to autodetect cases where
89 * the requested range is pote 92 * the requested range is potentially in System RAM.
90 */ 93 */
91 if (is_ram == REGION_INTERSECT 94 if (is_ram == REGION_INTERSECTS)
92 addr = try_ram_remap(o 95 addr = try_ram_remap(offset, size, flags);
93 if (!addr) 96 if (!addr)
94 addr = arch_memremap_w 97 addr = arch_memremap_wb(offset, size);
95 } 98 }
96 99
97 /* 100 /*
98 * If we don't have a mapping yet and 101 * If we don't have a mapping yet and other request flags are
99 * present then we will be attempting 102 * present then we will be attempting to establish a new virtual
100 * address mapping. Enforce that this 103 * address mapping. Enforce that this mapping is not aliasing
101 * System RAM. 104 * System RAM.
102 */ 105 */
103 if (!addr && is_ram == REGION_INTERSEC 106 if (!addr && is_ram == REGION_INTERSECTS && flags != MEMREMAP_WB) {
104 WARN_ONCE(1, "memremap attempt 107 WARN_ONCE(1, "memremap attempted on ram %pa size: %#lx\n",
105 &offset, (unsi 108 &offset, (unsigned long) size);
106 return NULL; 109 return NULL;
107 } 110 }
108 111
109 if (!addr && (flags & MEMREMAP_WT)) 112 if (!addr && (flags & MEMREMAP_WT))
110 addr = ioremap_wt(offset, size 113 addr = ioremap_wt(offset, size);
111 114
112 if (!addr && (flags & MEMREMAP_WC)) 115 if (!addr && (flags & MEMREMAP_WC))
113 addr = ioremap_wc(offset, size 116 addr = ioremap_wc(offset, size);
114 117
115 return addr; 118 return addr;
116 } 119 }
117 EXPORT_SYMBOL(memremap); 120 EXPORT_SYMBOL(memremap);
118 121
119 void memunmap(void *addr) 122 void memunmap(void *addr)
120 { 123 {
121 if (is_ioremap_addr(addr)) 124 if (is_ioremap_addr(addr))
122 iounmap((void __iomem *) addr) 125 iounmap((void __iomem *) addr);
123 } 126 }
124 EXPORT_SYMBOL(memunmap); 127 EXPORT_SYMBOL(memunmap);
125 128
126 static void devm_memremap_release(struct devic 129 static void devm_memremap_release(struct device *dev, void *res)
127 { 130 {
128 memunmap(*(void **)res); 131 memunmap(*(void **)res);
129 } 132 }
130 133
131 static int devm_memremap_match(struct device * 134 static int devm_memremap_match(struct device *dev, void *res, void *match_data)
132 { 135 {
133 return *(void **)res == match_data; 136 return *(void **)res == match_data;
134 } 137 }
135 138
136 void *devm_memremap(struct device *dev, resour 139 void *devm_memremap(struct device *dev, resource_size_t offset,
137 size_t size, unsigned long fla 140 size_t size, unsigned long flags)
138 { 141 {
139 void **ptr, *addr; 142 void **ptr, *addr;
140 143
141 ptr = devres_alloc_node(devm_memremap_ 144 ptr = devres_alloc_node(devm_memremap_release, sizeof(*ptr), GFP_KERNEL,
142 dev_to_node(dev)); 145 dev_to_node(dev));
143 if (!ptr) 146 if (!ptr)
144 return ERR_PTR(-ENOMEM); 147 return ERR_PTR(-ENOMEM);
145 148
146 addr = memremap(offset, size, flags); 149 addr = memremap(offset, size, flags);
147 if (addr) { 150 if (addr) {
148 *ptr = addr; 151 *ptr = addr;
149 devres_add(dev, ptr); 152 devres_add(dev, ptr);
150 } else { 153 } else {
151 devres_free(ptr); 154 devres_free(ptr);
152 return ERR_PTR(-ENXIO); 155 return ERR_PTR(-ENXIO);
153 } 156 }
154 157
155 return addr; 158 return addr;
156 } 159 }
157 EXPORT_SYMBOL(devm_memremap); 160 EXPORT_SYMBOL(devm_memremap);
158 161
159 void devm_memunmap(struct device *dev, void *a 162 void devm_memunmap(struct device *dev, void *addr)
160 { 163 {
161 WARN_ON(devres_release(dev, devm_memre 164 WARN_ON(devres_release(dev, devm_memremap_release,
162 devm_memremap_ 165 devm_memremap_match, addr));
163 } 166 }
164 EXPORT_SYMBOL(devm_memunmap); 167 EXPORT_SYMBOL(devm_memunmap);
165 168
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