xref: /linux/arch/arm64/include/asm/io.h (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
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 
21 /*
22  * Generic IO read/write.  These perform native-endian accesses.
23  */
24 #define __raw_writeb __raw_writeb
25 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
26 {
27 	asm volatile("strb %w0, [%1]" : : "rZ" (val), "r" (addr));
28 }
29 
30 #define __raw_writew __raw_writew
31 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
32 {
33 	asm volatile("strh %w0, [%1]" : : "rZ" (val), "r" (addr));
34 }
35 
36 #define __raw_writel __raw_writel
37 static __always_inline void __raw_writel(u32 val, volatile void __iomem *addr)
38 {
39 	asm volatile("str %w0, [%1]" : : "rZ" (val), "r" (addr));
40 }
41 
42 #define __raw_writeq __raw_writeq
43 static inline void __raw_writeq(u64 val, volatile void __iomem *addr)
44 {
45 	asm volatile("str %x0, [%1]" : : "rZ" (val), "r" (addr));
46 }
47 
48 #define __raw_readb __raw_readb
49 static inline u8 __raw_readb(const volatile void __iomem *addr)
50 {
51 	u8 val;
52 	asm volatile(ALTERNATIVE("ldrb %w0, [%1]",
53 				 "ldarb %w0, [%1]",
54 				 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
55 		     : "=r" (val) : "r" (addr));
56 	return val;
57 }
58 
59 #define __raw_readw __raw_readw
60 static inline u16 __raw_readw(const volatile void __iomem *addr)
61 {
62 	u16 val;
63 
64 	asm volatile(ALTERNATIVE("ldrh %w0, [%1]",
65 				 "ldarh %w0, [%1]",
66 				 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
67 		     : "=r" (val) : "r" (addr));
68 	return val;
69 }
70 
71 #define __raw_readl __raw_readl
72 static __always_inline u32 __raw_readl(const volatile void __iomem *addr)
73 {
74 	u32 val;
75 	asm volatile(ALTERNATIVE("ldr %w0, [%1]",
76 				 "ldar %w0, [%1]",
77 				 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
78 		     : "=r" (val) : "r" (addr));
79 	return val;
80 }
81 
82 #define __raw_readq __raw_readq
83 static inline u64 __raw_readq(const volatile void __iomem *addr)
84 {
85 	u64 val;
86 	asm volatile(ALTERNATIVE("ldr %0, [%1]",
87 				 "ldar %0, [%1]",
88 				 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
89 		     : "=r" (val) : "r" (addr));
90 	return val;
91 }
92 
93 /* IO barriers */
94 #define __iormb(v)							\
95 ({									\
96 	unsigned long tmp;						\
97 									\
98 	dma_rmb();								\
99 									\
100 	/*								\
101 	 * Create a dummy control dependency from the IO read to any	\
102 	 * later instructions. This ensures that a subsequent call to	\
103 	 * udelay() will be ordered due to the ISB in get_cycles().	\
104 	 */								\
105 	asm volatile("eor	%0, %1, %1\n"				\
106 		     "cbnz	%0, ."					\
107 		     : "=r" (tmp) : "r" ((unsigned long)(v))		\
108 		     : "memory");					\
109 })
110 
111 #define __io_par(v)		__iormb(v)
112 #define __iowmb()		dma_wmb()
113 #define __iomb()		dma_mb()
114 
115 /*
116  * Relaxed I/O memory access primitives. These follow the Device memory
117  * ordering rules but do not guarantee any ordering relative to Normal memory
118  * accesses.
119  */
120 #define readb_relaxed(c)	({ u8  __r = __raw_readb(c); __r; })
121 #define readw_relaxed(c)	({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; })
122 #define readl_relaxed(c)	({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
123 #define readq_relaxed(c)	({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; })
124 
125 #define writeb_relaxed(v,c)	((void)__raw_writeb((v),(c)))
126 #define writew_relaxed(v,c)	((void)__raw_writew((__force u16)cpu_to_le16(v),(c)))
127 #define writel_relaxed(v,c)	((void)__raw_writel((__force u32)cpu_to_le32(v),(c)))
128 #define writeq_relaxed(v,c)	((void)__raw_writeq((__force u64)cpu_to_le64(v),(c)))
129 
130 /*
131  * I/O memory access primitives. Reads are ordered relative to any
132  * following Normal memory access. Writes are ordered relative to any prior
133  * Normal memory access.
134  */
135 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(__v); __v; })
136 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(__v); __v; })
137 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(__v); __v; })
138 #define readq(c)		({ u64 __v = readq_relaxed(c); __iormb(__v); __v; })
139 
140 #define writeb(v,c)		({ __iowmb(); writeb_relaxed((v),(c)); })
141 #define writew(v,c)		({ __iowmb(); writew_relaxed((v),(c)); })
142 #define writel(v,c)		({ __iowmb(); writel_relaxed((v),(c)); })
143 #define writeq(v,c)		({ __iowmb(); writeq_relaxed((v),(c)); })
144 
145 /*
146  *  I/O port access primitives.
147  */
148 #define arch_has_dev_port()	(1)
149 #define IO_SPACE_LIMIT		(PCI_IO_SIZE - 1)
150 #define PCI_IOBASE		((void __iomem *)PCI_IO_START)
151 
152 /*
153  * String version of I/O memory access operations.
154  */
155 extern void __memcpy_fromio(void *, const volatile void __iomem *, size_t);
156 extern void __memcpy_toio(volatile void __iomem *, const void *, size_t);
157 extern void __memset_io(volatile void __iomem *, int, size_t);
158 
159 #define memset_io(c,v,l)	__memset_io((c),(v),(l))
160 #define memcpy_fromio(a,c,l)	__memcpy_fromio((a),(c),(l))
161 #define memcpy_toio(c,a,l)	__memcpy_toio((c),(a),(l))
162 
163 /*
164  * I/O memory mapping functions.
165  */
166 extern void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot);
167 extern void iounmap(volatile void __iomem *addr);
168 extern void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size);
169 
170 #define ioremap(addr, size)		__ioremap((addr), (size), __pgprot(PROT_DEVICE_nGnRE))
171 #define ioremap_wc(addr, size)		__ioremap((addr), (size), __pgprot(PROT_NORMAL_NC))
172 
173 /*
174  * PCI configuration space mapping function.
175  *
176  * The PCI specification disallows posted write configuration transactions.
177  * Add an arch specific pci_remap_cfgspace() definition that is implemented
178  * through nGnRnE device memory attribute as recommended by the ARM v8
179  * Architecture reference manual Issue A.k B2.8.2 "Device memory".
180  */
181 #define pci_remap_cfgspace(addr, size) __ioremap((addr), (size), __pgprot(PROT_DEVICE_nGnRnE))
182 
183 /*
184  * io{read,write}{16,32,64}be() macros
185  */
186 #define ioread16be(p)		({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(__v); __v; })
187 #define ioread32be(p)		({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(__v); __v; })
188 #define ioread64be(p)		({ __u64 __v = be64_to_cpu((__force __be64)__raw_readq(p)); __iormb(__v); __v; })
189 
190 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
191 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
192 #define iowrite64be(v,p)	({ __iowmb(); __raw_writeq((__force __u64)cpu_to_be64(v), p); })
193 
194 #include <asm-generic/io.h>
195 
196 /*
197  * More restrictive address range checking than the default implementation
198  * (PHYS_OFFSET and PHYS_MASK taken into account).
199  */
200 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
201 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
202 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
203 
204 #endif	/* __ASM_IO_H */
205