1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * {read,write}{b,w,l,q} based on arch/arm64/include/asm/io.h
4 *   which was based on arch/arm/include/io.h
5 *
6 * Copyright (C) 1996-2000 Russell King
7 * Copyright (C) 2012 ARM Ltd.
8 * Copyright (C) 2014 Regents of the University of California
9 */
10
11#ifndef _ASM_RISCV_MMIO_H
12#define _ASM_RISCV_MMIO_H
13
14#include <linux/types.h>
15#include <asm/fence.h>
16#include <asm/mmiowb.h>
17
18/* Generic IO read/write.  These perform native-endian accesses. */
19#define __raw_writeb __raw_writeb
20static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
21{
22	asm volatile("sb %0, 0(%1)" : : "r" (val), "r" (addr));
23}
24
25#define __raw_writew __raw_writew
26static inline void __raw_writew(u16 val, volatile void __iomem *addr)
27{
28	asm volatile("sh %0, 0(%1)" : : "r" (val), "r" (addr));
29}
30
31#define __raw_writel __raw_writel
32static inline void __raw_writel(u32 val, volatile void __iomem *addr)
33{
34	asm volatile("sw %0, 0(%1)" : : "r" (val), "r" (addr));
35}
36
37#ifdef CONFIG_64BIT
38#define __raw_writeq __raw_writeq
39static inline void __raw_writeq(u64 val, volatile void __iomem *addr)
40{
41	asm volatile("sd %0, 0(%1)" : : "r" (val), "r" (addr));
42}
43#endif
44
45#define __raw_readb __raw_readb
46static inline u8 __raw_readb(const volatile void __iomem *addr)
47{
48	u8 val;
49
50	asm volatile("lb %0, 0(%1)" : "=r" (val) : "r" (addr));
51	return val;
52}
53
54#define __raw_readw __raw_readw
55static inline u16 __raw_readw(const volatile void __iomem *addr)
56{
57	u16 val;
58
59	asm volatile("lh %0, 0(%1)" : "=r" (val) : "r" (addr));
60	return val;
61}
62
63#define __raw_readl __raw_readl
64static inline u32 __raw_readl(const volatile void __iomem *addr)
65{
66	u32 val;
67
68	asm volatile("lw %0, 0(%1)" : "=r" (val) : "r" (addr));
69	return val;
70}
71
72#ifdef CONFIG_64BIT
73#define __raw_readq __raw_readq
74static inline u64 __raw_readq(const volatile void __iomem *addr)
75{
76	u64 val;
77
78	asm volatile("ld %0, 0(%1)" : "=r" (val) : "r" (addr));
79	return val;
80}
81#endif
82
83/*
84 * Unordered I/O memory access primitives.  These are even more relaxed than
85 * the relaxed versions, as they don't even order accesses between successive
86 * operations to the I/O regions.
87 */
88#define readb_cpu(c)		({ u8  __r = __raw_readb(c); __r; })
89#define readw_cpu(c)		({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; })
90#define readl_cpu(c)		({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
91
92#define writeb_cpu(v, c)	((void)__raw_writeb((v), (c)))
93#define writew_cpu(v, c)	((void)__raw_writew((__force u16)cpu_to_le16(v), (c)))
94#define writel_cpu(v, c)	((void)__raw_writel((__force u32)cpu_to_le32(v), (c)))
95
96#ifdef CONFIG_64BIT
97#define readq_cpu(c)		({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; })
98#define writeq_cpu(v, c)	((void)__raw_writeq((__force u64)cpu_to_le64(v), (c)))
99#endif
100
101/*
102 * Relaxed I/O memory access primitives. These follow the Device memory
103 * ordering rules but do not guarantee any ordering relative to Normal memory
104 * accesses.  These are defined to order the indicated access (either a read or
105 * write) with all other I/O memory accesses to the same peripheral. Since the
106 * platform specification defines that all I/O regions are strongly ordered on
107 * channel 0, no explicit fences are required to enforce this ordering.
108 */
109/* FIXME: These are now the same as asm-generic */
110#define __io_rbr()		do {} while (0)
111#define __io_rar()		do {} while (0)
112#define __io_rbw()		do {} while (0)
113#define __io_raw()		do {} while (0)
114
115#define readb_relaxed(c)	({ u8  __v; __io_rbr(); __v = readb_cpu(c); __io_rar(); __v; })
116#define readw_relaxed(c)	({ u16 __v; __io_rbr(); __v = readw_cpu(c); __io_rar(); __v; })
117#define readl_relaxed(c)	({ u32 __v; __io_rbr(); __v = readl_cpu(c); __io_rar(); __v; })
118
119#define writeb_relaxed(v, c)	({ __io_rbw(); writeb_cpu((v), (c)); __io_raw(); })
120#define writew_relaxed(v, c)	({ __io_rbw(); writew_cpu((v), (c)); __io_raw(); })
121#define writel_relaxed(v, c)	({ __io_rbw(); writel_cpu((v), (c)); __io_raw(); })
122
123#ifdef CONFIG_64BIT
124#define readq_relaxed(c)	({ u64 __v; __io_rbr(); __v = readq_cpu(c); __io_rar(); __v; })
125#define writeq_relaxed(v, c)	({ __io_rbw(); writeq_cpu((v), (c)); __io_raw(); })
126#endif
127
128/*
129 * I/O memory access primitives.  Reads are ordered relative to any following
130 * Normal memory read and delay() loop.  Writes are ordered relative to any
131 * prior Normal memory write.  The memory barriers here are necessary as RISC-V
132 * doesn't define any ordering between the memory space and the I/O space.
133 */
134#define __io_br()	do {} while (0)
135#define __io_ar(v)	RISCV_FENCE(i, ir)
136#define __io_bw()	RISCV_FENCE(w, o)
137#define __io_aw()	mmiowb_set_pending()
138
139#define readb(c)	({ u8  __v; __io_br(); __v = readb_cpu(c); __io_ar(__v); __v; })
140#define readw(c)	({ u16 __v; __io_br(); __v = readw_cpu(c); __io_ar(__v); __v; })
141#define readl(c)	({ u32 __v; __io_br(); __v = readl_cpu(c); __io_ar(__v); __v; })
142
143#define writeb(v, c)	({ __io_bw(); writeb_cpu((v), (c)); __io_aw(); })
144#define writew(v, c)	({ __io_bw(); writew_cpu((v), (c)); __io_aw(); })
145#define writel(v, c)	({ __io_bw(); writel_cpu((v), (c)); __io_aw(); })
146
147#ifdef CONFIG_64BIT
148#define readq(c)	({ u64 __v; __io_br(); __v = readq_cpu(c); __io_ar(__v); __v; })
149#define writeq(v, c)	({ __io_bw(); writeq_cpu((v), (c)); __io_aw(); })
150#endif
151
152#endif /* _ASM_RISCV_MMIO_H */
153