xref: /openbmc/linux/arch/arc/include/asm/io.h (revision 4f6cce39)
1 /*
2  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #ifndef _ASM_ARC_IO_H
10 #define _ASM_ARC_IO_H
11 
12 #include <linux/types.h>
13 #include <asm/byteorder.h>
14 #include <asm/page.h>
15 
16 #ifdef CONFIG_ISA_ARCV2
17 #include <asm/barrier.h>
18 #define __iormb()		rmb()
19 #define __iowmb()		wmb()
20 #else
21 #define __iormb()		do { } while (0)
22 #define __iowmb()		do { } while (0)
23 #endif
24 
25 extern void __iomem *ioremap(phys_addr_t paddr, unsigned long size);
26 extern void __iomem *ioremap_prot(phys_addr_t paddr, unsigned long size,
27 				  unsigned long flags);
28 static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
29 {
30 	return (void __iomem *)port;
31 }
32 
33 static inline void ioport_unmap(void __iomem *addr)
34 {
35 }
36 
37 extern void iounmap(const void __iomem *addr);
38 
39 #define ioremap_nocache(phy, sz)	ioremap(phy, sz)
40 #define ioremap_wc(phy, sz)		ioremap(phy, sz)
41 #define ioremap_wt(phy, sz)		ioremap(phy, sz)
42 
43 /*
44  * io{read,write}{16,32}be() macros
45  */
46 #define ioread16be(p)		({ u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
47 #define ioread32be(p)		({ u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
48 
49 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force u16)cpu_to_be16(v), p); })
50 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force u32)cpu_to_be32(v), p); })
51 
52 /* Change struct page to physical address */
53 #define page_to_phys(page)		(page_to_pfn(page) << PAGE_SHIFT)
54 
55 #define __raw_readb __raw_readb
56 static inline u8 __raw_readb(const volatile void __iomem *addr)
57 {
58 	u8 b;
59 
60 	__asm__ __volatile__(
61 	"	ldb%U1 %0, %1	\n"
62 	: "=r" (b)
63 	: "m" (*(volatile u8 __force *)addr)
64 	: "memory");
65 
66 	return b;
67 }
68 
69 #define __raw_readw __raw_readw
70 static inline u16 __raw_readw(const volatile void __iomem *addr)
71 {
72 	u16 s;
73 
74 	__asm__ __volatile__(
75 	"	ldw%U1 %0, %1	\n"
76 	: "=r" (s)
77 	: "m" (*(volatile u16 __force *)addr)
78 	: "memory");
79 
80 	return s;
81 }
82 
83 #define __raw_readl __raw_readl
84 static inline u32 __raw_readl(const volatile void __iomem *addr)
85 {
86 	u32 w;
87 
88 	__asm__ __volatile__(
89 	"	ld%U1 %0, %1	\n"
90 	: "=r" (w)
91 	: "m" (*(volatile u32 __force *)addr)
92 	: "memory");
93 
94 	return w;
95 }
96 
97 #define __raw_writeb __raw_writeb
98 static inline void __raw_writeb(u8 b, volatile void __iomem *addr)
99 {
100 	__asm__ __volatile__(
101 	"	stb%U1 %0, %1	\n"
102 	:
103 	: "r" (b), "m" (*(volatile u8 __force *)addr)
104 	: "memory");
105 }
106 
107 #define __raw_writew __raw_writew
108 static inline void __raw_writew(u16 s, volatile void __iomem *addr)
109 {
110 	__asm__ __volatile__(
111 	"	stw%U1 %0, %1	\n"
112 	:
113 	: "r" (s), "m" (*(volatile u16 __force *)addr)
114 	: "memory");
115 
116 }
117 
118 #define __raw_writel __raw_writel
119 static inline void __raw_writel(u32 w, volatile void __iomem *addr)
120 {
121 	__asm__ __volatile__(
122 	"	st%U1 %0, %1	\n"
123 	:
124 	: "r" (w), "m" (*(volatile u32 __force *)addr)
125 	: "memory");
126 
127 }
128 
129 /*
130  * MMIO can also get buffered/optimized in micro-arch, so barriers needed
131  * Based on ARM model for the typical use case
132  *
133  *	<ST [DMA buffer]>
134  *	<writel MMIO "go" reg>
135  *  or:
136  *	<readl MMIO "status" reg>
137  *	<LD [DMA buffer]>
138  *
139  * http://lkml.kernel.org/r/20150622133656.GG1583@arm.com
140  */
141 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
142 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
143 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
144 
145 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
146 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
147 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
148 
149 /*
150  * Relaxed API for drivers which can handle barrier ordering themselves
151  *
152  * Also these are defined to perform little endian accesses.
153  * To provide the typical device register semantics of fixed endian,
154  * swap the byte order for Big Endian
155  *
156  * http://lkml.kernel.org/r/201603100845.30602.arnd@arndb.de
157  */
158 #define readb_relaxed(c)	__raw_readb(c)
159 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
160 					__raw_readw(c)); __r; })
161 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
162 					__raw_readl(c)); __r; })
163 
164 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
165 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
166 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
167 
168 #include <asm-generic/io.h>
169 
170 #endif /* _ASM_ARC_IO_H */
171