1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Based on arch/arm/include/asm/io.h
4 *
5 * Copyright (C) 1996-2000 Russell King
6 * Copyright (C) 2012 ARM Ltd.
7 */
8 #ifndef __ASM_IO_H
9 #define __ASM_IO_H
10
11 #include <linux/types.h>
12 #include <linux/pgtable.h>
13
14 #include <asm/byteorder.h>
15 #include <asm/barrier.h>
16 #include <asm/memory.h>
17 #include <asm/early_ioremap.h>
18 #include <asm/alternative.h>
19 #include <asm/cpufeature.h>
20 #include <asm/rsi.h>
21
22 /*
23 * Generic IO read/write. These perform native-endian accesses.
24 */
25 #define __raw_writeb __raw_writeb
__raw_writeb(u8 val,volatile void __iomem * addr)26 static __always_inline void __raw_writeb(u8 val, volatile void __iomem *addr)
27 {
28 volatile u8 __iomem *ptr = addr;
29 asm volatile("strb %w0, %1" : : "rZ" (val), "Qo" (*ptr));
30 }
31
32 #define __raw_writew __raw_writew
__raw_writew(u16 val,volatile void __iomem * addr)33 static __always_inline void __raw_writew(u16 val, volatile void __iomem *addr)
34 {
35 volatile u16 __iomem *ptr = addr;
36 asm volatile("strh %w0, %1" : : "rZ" (val), "Qo" (*ptr));
37 }
38
39 #define __raw_writel __raw_writel
__raw_writel(u32 val,volatile void __iomem * addr)40 static __always_inline void __raw_writel(u32 val, volatile void __iomem *addr)
41 {
42 volatile u32 __iomem *ptr = addr;
43 asm volatile("str %w0, %1" : : "rZ" (val), "Qo" (*ptr));
44 }
45
46 #define __raw_writeq __raw_writeq
__raw_writeq(u64 val,volatile void __iomem * addr)47 static __always_inline void __raw_writeq(u64 val, volatile void __iomem *addr)
48 {
49 volatile u64 __iomem *ptr = addr;
50 asm volatile("str %x0, %1" : : "rZ" (val), "Qo" (*ptr));
51 }
52
53 #define __raw_readb __raw_readb
__raw_readb(const volatile void __iomem * addr)54 static __always_inline u8 __raw_readb(const volatile void __iomem *addr)
55 {
56 u8 val;
57 asm volatile(ALTERNATIVE("ldrb %w0, [%1]",
58 "ldarb %w0, [%1]",
59 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
60 : "=r" (val) : "r" (addr));
61 return val;
62 }
63
64 #define __raw_readw __raw_readw
__raw_readw(const volatile void __iomem * addr)65 static __always_inline u16 __raw_readw(const volatile void __iomem *addr)
66 {
67 u16 val;
68
69 asm volatile(ALTERNATIVE("ldrh %w0, [%1]",
70 "ldarh %w0, [%1]",
71 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
72 : "=r" (val) : "r" (addr));
73 return val;
74 }
75
76 #define __raw_readl __raw_readl
__raw_readl(const volatile void __iomem * addr)77 static __always_inline u32 __raw_readl(const volatile void __iomem *addr)
78 {
79 u32 val;
80 asm volatile(ALTERNATIVE("ldr %w0, [%1]",
81 "ldar %w0, [%1]",
82 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
83 : "=r" (val) : "r" (addr));
84 return val;
85 }
86
87 #define __raw_readq __raw_readq
__raw_readq(const volatile void __iomem * addr)88 static __always_inline u64 __raw_readq(const volatile void __iomem *addr)
89 {
90 u64 val;
91 asm volatile(ALTERNATIVE("ldr %0, [%1]",
92 "ldar %0, [%1]",
93 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
94 : "=r" (val) : "r" (addr));
95 return val;
96 }
97
98 /* IO barriers */
99 #define __io_ar(v) \
100 ({ \
101 unsigned long tmp; \
102 \
103 dma_rmb(); \
104 \
105 /* \
106 * Create a dummy control dependency from the IO read to any \
107 * later instructions. This ensures that a subsequent call to \
108 * udelay() will be ordered due to the ISB in get_cycles(). \
109 */ \
110 asm volatile("eor %0, %1, %1\n" \
111 "cbnz %0, ." \
112 : "=r" (tmp) : "r" ((unsigned long)(v)) \
113 : "memory"); \
114 })
115
116 #define __io_bw() dma_wmb()
117 #define __io_br(v)
118 #define __io_aw(v)
119
120 /* arm64-specific, don't use in portable drivers */
121 #define __iormb(v) __io_ar(v)
122 #define __iowmb() __io_bw()
123 #define __iomb() dma_mb()
124
125 /*
126 * I/O port access primitives.
127 */
128 #define arch_has_dev_port() (1)
129 #define IO_SPACE_LIMIT (PCI_IO_SIZE - 1)
130 #define PCI_IOBASE ((void __iomem *)PCI_IO_START)
131
132 /*
133 * The ARM64 iowrite implementation is intended to support drivers that want to
134 * use write combining. For instance PCI drivers using write combining with a 64
135 * byte __iowrite64_copy() expect to get a 64 byte MemWr TLP on the PCIe bus.
136 *
137 * Newer ARM core have sensitive write combining buffers, it is important that
138 * the stores be contiguous blocks of store instructions. Normal memcpy
139 * approaches have a very low chance to generate write combining.
140 *
141 * Since this is the only API on ARM64 that should be used with write combining
142 * it also integrates the DGH hint which is supposed to lower the latency to
143 * emit the large TLP from the CPU.
144 */
145
146 static __always_inline void
__const_memcpy_toio_aligned32(volatile u32 __iomem * to,const u32 * from,size_t count)147 __const_memcpy_toio_aligned32(volatile u32 __iomem *to, const u32 *from,
148 size_t count)
149 {
150 switch (count) {
151 case 8:
152 asm volatile("str %w0, [%8, #4 * 0]\n"
153 "str %w1, [%8, #4 * 1]\n"
154 "str %w2, [%8, #4 * 2]\n"
155 "str %w3, [%8, #4 * 3]\n"
156 "str %w4, [%8, #4 * 4]\n"
157 "str %w5, [%8, #4 * 5]\n"
158 "str %w6, [%8, #4 * 6]\n"
159 "str %w7, [%8, #4 * 7]\n"
160 :
161 : "rZ"(from[0]), "rZ"(from[1]), "rZ"(from[2]),
162 "rZ"(from[3]), "rZ"(from[4]), "rZ"(from[5]),
163 "rZ"(from[6]), "rZ"(from[7]), "r"(to));
164 break;
165 case 4:
166 asm volatile("str %w0, [%4, #4 * 0]\n"
167 "str %w1, [%4, #4 * 1]\n"
168 "str %w2, [%4, #4 * 2]\n"
169 "str %w3, [%4, #4 * 3]\n"
170 :
171 : "rZ"(from[0]), "rZ"(from[1]), "rZ"(from[2]),
172 "rZ"(from[3]), "r"(to));
173 break;
174 case 2:
175 asm volatile("str %w0, [%2, #4 * 0]\n"
176 "str %w1, [%2, #4 * 1]\n"
177 :
178 : "rZ"(from[0]), "rZ"(from[1]), "r"(to));
179 break;
180 case 1:
181 __raw_writel(*from, to);
182 break;
183 default:
184 BUILD_BUG();
185 }
186 }
187
188 void __iowrite32_copy_full(void __iomem *to, const void *from, size_t count);
189
190 static __always_inline void
__iowrite32_copy(void __iomem * to,const void * from,size_t count)191 __iowrite32_copy(void __iomem *to, const void *from, size_t count)
192 {
193 if (__builtin_constant_p(count) &&
194 (count == 8 || count == 4 || count == 2 || count == 1)) {
195 __const_memcpy_toio_aligned32(to, from, count);
196 dgh();
197 } else {
198 __iowrite32_copy_full(to, from, count);
199 }
200 }
201 #define __iowrite32_copy __iowrite32_copy
202
203 static __always_inline void
__const_memcpy_toio_aligned64(volatile u64 __iomem * to,const u64 * from,size_t count)204 __const_memcpy_toio_aligned64(volatile u64 __iomem *to, const u64 *from,
205 size_t count)
206 {
207 switch (count) {
208 case 8:
209 asm volatile("str %x0, [%8, #8 * 0]\n"
210 "str %x1, [%8, #8 * 1]\n"
211 "str %x2, [%8, #8 * 2]\n"
212 "str %x3, [%8, #8 * 3]\n"
213 "str %x4, [%8, #8 * 4]\n"
214 "str %x5, [%8, #8 * 5]\n"
215 "str %x6, [%8, #8 * 6]\n"
216 "str %x7, [%8, #8 * 7]\n"
217 :
218 : "rZ"(from[0]), "rZ"(from[1]), "rZ"(from[2]),
219 "rZ"(from[3]), "rZ"(from[4]), "rZ"(from[5]),
220 "rZ"(from[6]), "rZ"(from[7]), "r"(to));
221 break;
222 case 4:
223 asm volatile("str %x0, [%4, #8 * 0]\n"
224 "str %x1, [%4, #8 * 1]\n"
225 "str %x2, [%4, #8 * 2]\n"
226 "str %x3, [%4, #8 * 3]\n"
227 :
228 : "rZ"(from[0]), "rZ"(from[1]), "rZ"(from[2]),
229 "rZ"(from[3]), "r"(to));
230 break;
231 case 2:
232 asm volatile("str %x0, [%2, #8 * 0]\n"
233 "str %x1, [%2, #8 * 1]\n"
234 :
235 : "rZ"(from[0]), "rZ"(from[1]), "r"(to));
236 break;
237 case 1:
238 __raw_writeq(*from, to);
239 break;
240 default:
241 BUILD_BUG();
242 }
243 }
244
245 void __iowrite64_copy_full(void __iomem *to, const void *from, size_t count);
246
247 static __always_inline void
__iowrite64_copy(void __iomem * to,const void * from,size_t count)248 __iowrite64_copy(void __iomem *to, const void *from, size_t count)
249 {
250 if (__builtin_constant_p(count) &&
251 (count == 8 || count == 4 || count == 2 || count == 1)) {
252 __const_memcpy_toio_aligned64(to, from, count);
253 dgh();
254 } else {
255 __iowrite64_copy_full(to, from, count);
256 }
257 }
258 #define __iowrite64_copy __iowrite64_copy
259
260 /*
261 * I/O memory mapping functions.
262 */
263
264 typedef int (*ioremap_prot_hook_t)(phys_addr_t phys_addr, size_t size,
265 pgprot_t *prot);
266 int arm64_ioremap_prot_hook_register(const ioremap_prot_hook_t hook);
267
268 #define ioremap_prot ioremap_prot
269
270 #define _PAGE_IOREMAP PROT_DEVICE_nGnRE
271
272 #define ioremap_wc(addr, size) \
273 ioremap_prot((addr), (size), PROT_NORMAL_NC)
274 #define ioremap_np(addr, size) \
275 ioremap_prot((addr), (size), PROT_DEVICE_nGnRnE)
276
277 /*
278 * io{read,write}{16,32,64}be() macros
279 */
280 #define ioread16be(p) ({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(__v); __v; })
281 #define ioread32be(p) ({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(__v); __v; })
282 #define ioread64be(p) ({ __u64 __v = be64_to_cpu((__force __be64)__raw_readq(p)); __iormb(__v); __v; })
283
284 #define iowrite16be(v,p) ({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
285 #define iowrite32be(v,p) ({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
286 #define iowrite64be(v,p) ({ __iowmb(); __raw_writeq((__force __u64)cpu_to_be64(v), p); })
287
288 #include <asm-generic/io.h>
289
290 #define ioremap_cache ioremap_cache
ioremap_cache(phys_addr_t addr,size_t size)291 static inline void __iomem *ioremap_cache(phys_addr_t addr, size_t size)
292 {
293 if (pfn_is_map_memory(__phys_to_pfn(addr)))
294 return (void __iomem *)__phys_to_virt(addr);
295
296 return ioremap_prot(addr, size, PROT_NORMAL);
297 }
298
299 /*
300 * More restrictive address range checking than the default implementation
301 * (PHYS_OFFSET and PHYS_MASK taken into account).
302 */
303 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
304 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
305 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
306
307 extern bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
308 unsigned long flags);
309 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
310
arm64_is_protected_mmio(phys_addr_t phys_addr,size_t size)311 static inline bool arm64_is_protected_mmio(phys_addr_t phys_addr, size_t size)
312 {
313 if (unlikely(is_realm_world()))
314 return __arm64_is_protected_mmio(phys_addr, size);
315 return false;
316 }
317
318 #endif /* __ASM_IO_H */
319