xref: /linux/arch/arm64/include/asm/io.h (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /*
2  * Based on arch/arm/include/asm/io.h
3  *
4  * Copyright (C) 1996-2000 Russell King
5  * Copyright (C) 2012 ARM Ltd.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 #ifndef __ASM_IO_H
20 #define __ASM_IO_H
21 
22 #ifdef __KERNEL__
23 
24 #include <linux/types.h>
25 #include <linux/blk_types.h>
26 
27 #include <asm/byteorder.h>
28 #include <asm/barrier.h>
29 #include <asm/memory.h>
30 #include <asm/pgtable.h>
31 #include <asm/early_ioremap.h>
32 #include <asm/alternative.h>
33 #include <asm/cpufeature.h>
34 
35 #include <xen/xen.h>
36 
37 /*
38  * Generic IO read/write.  These perform native-endian accesses.
39  */
40 #define __raw_writeb __raw_writeb
41 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
42 {
43 	asm volatile("strb %w0, [%1]" : : "r" (val), "r" (addr));
44 }
45 
46 #define __raw_writew __raw_writew
47 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
48 {
49 	asm volatile("strh %w0, [%1]" : : "r" (val), "r" (addr));
50 }
51 
52 #define __raw_writel __raw_writel
53 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
54 {
55 	asm volatile("str %w0, [%1]" : : "r" (val), "r" (addr));
56 }
57 
58 #define __raw_writeq __raw_writeq
59 static inline void __raw_writeq(u64 val, volatile void __iomem *addr)
60 {
61 	asm volatile("str %0, [%1]" : : "r" (val), "r" (addr));
62 }
63 
64 #define __raw_readb __raw_readb
65 static inline u8 __raw_readb(const volatile void __iomem *addr)
66 {
67 	u8 val;
68 	asm volatile(ALTERNATIVE("ldrb %w0, [%1]",
69 				 "ldarb %w0, [%1]",
70 				 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
71 		     : "=r" (val) : "r" (addr));
72 	return val;
73 }
74 
75 #define __raw_readw __raw_readw
76 static inline u16 __raw_readw(const volatile void __iomem *addr)
77 {
78 	u16 val;
79 
80 	asm volatile(ALTERNATIVE("ldrh %w0, [%1]",
81 				 "ldarh %w0, [%1]",
82 				 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
83 		     : "=r" (val) : "r" (addr));
84 	return val;
85 }
86 
87 #define __raw_readl __raw_readl
88 static inline u32 __raw_readl(const volatile void __iomem *addr)
89 {
90 	u32 val;
91 	asm volatile(ALTERNATIVE("ldr %w0, [%1]",
92 				 "ldar %w0, [%1]",
93 				 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
94 		     : "=r" (val) : "r" (addr));
95 	return val;
96 }
97 
98 #define __raw_readq __raw_readq
99 static inline u64 __raw_readq(const volatile void __iomem *addr)
100 {
101 	u64 val;
102 	asm volatile(ALTERNATIVE("ldr %0, [%1]",
103 				 "ldar %0, [%1]",
104 				 ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
105 		     : "=r" (val) : "r" (addr));
106 	return val;
107 }
108 
109 /* IO barriers */
110 #define __iormb()		rmb()
111 #define __iowmb()		wmb()
112 
113 #define mmiowb()		do { } while (0)
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; })
136 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
137 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
138 #define readq(c)		({ u64 __v = readq_relaxed(c); __iormb(); __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_nocache(addr, size)	__ioremap((addr), (size), __pgprot(PROT_DEVICE_nGnRE))
172 #define ioremap_wc(addr, size)		__ioremap((addr), (size), __pgprot(PROT_NORMAL_NC))
173 #define ioremap_wt(addr, size)		__ioremap((addr), (size), __pgprot(PROT_DEVICE_nGnRE))
174 #define iounmap				__iounmap
175 
176 /*
177  * io{read,write}{16,32}be() macros
178  */
179 #define ioread16be(p)		({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
180 #define ioread32be(p)		({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
181 
182 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
183 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
184 
185 /*
186  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
187  * access
188  */
189 #define xlate_dev_mem_ptr(p)	__va(p)
190 
191 /*
192  * Convert a virtual cached pointer to an uncached pointer
193  */
194 #define xlate_dev_kmem_ptr(p)	p
195 
196 #include <asm-generic/io.h>
197 
198 /*
199  * More restrictive address range checking than the default implementation
200  * (PHYS_OFFSET and PHYS_MASK taken into account).
201  */
202 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
203 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
204 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
205 
206 extern int devmem_is_allowed(unsigned long pfn);
207 
208 struct bio_vec;
209 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
210 				      const struct bio_vec *vec2);
211 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
212 	(__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&				\
213 	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
214 
215 #endif	/* __KERNEL__ */
216 #endif	/* __ASM_IO_H */
217