xref: /openbmc/linux/arch/riscv/include/asm/io.h (revision 4b4f3acc)
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_IO_H
12 #define _ASM_RISCV_IO_H
13 
14 #include <linux/types.h>
15 #include <asm/mmiowb.h>
16 
17 extern void __iomem *ioremap(phys_addr_t offset, unsigned long size);
18 
19 /*
20  * The RISC-V ISA doesn't yet specify how to query or modify PMAs, so we can't
21  * change the properties of memory regions.  This should be fixed by the
22  * upcoming platform spec.
23  */
24 #define ioremap_nocache(addr, size) ioremap((addr), (size))
25 #define ioremap_wc(addr, size) ioremap((addr), (size))
26 #define ioremap_wt(addr, size) ioremap((addr), (size))
27 
28 extern void iounmap(volatile void __iomem *addr);
29 
30 /* Generic IO read/write.  These perform native-endian accesses. */
31 #define __raw_writeb __raw_writeb
32 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
33 {
34 	asm volatile("sb %0, 0(%1)" : : "r" (val), "r" (addr));
35 }
36 
37 #define __raw_writew __raw_writew
38 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
39 {
40 	asm volatile("sh %0, 0(%1)" : : "r" (val), "r" (addr));
41 }
42 
43 #define __raw_writel __raw_writel
44 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
45 {
46 	asm volatile("sw %0, 0(%1)" : : "r" (val), "r" (addr));
47 }
48 
49 #ifdef CONFIG_64BIT
50 #define __raw_writeq __raw_writeq
51 static inline void __raw_writeq(u64 val, volatile void __iomem *addr)
52 {
53 	asm volatile("sd %0, 0(%1)" : : "r" (val), "r" (addr));
54 }
55 #endif
56 
57 #define __raw_readb __raw_readb
58 static inline u8 __raw_readb(const volatile void __iomem *addr)
59 {
60 	u8 val;
61 
62 	asm volatile("lb %0, 0(%1)" : "=r" (val) : "r" (addr));
63 	return val;
64 }
65 
66 #define __raw_readw __raw_readw
67 static inline u16 __raw_readw(const volatile void __iomem *addr)
68 {
69 	u16 val;
70 
71 	asm volatile("lh %0, 0(%1)" : "=r" (val) : "r" (addr));
72 	return val;
73 }
74 
75 #define __raw_readl __raw_readl
76 static inline u32 __raw_readl(const volatile void __iomem *addr)
77 {
78 	u32 val;
79 
80 	asm volatile("lw %0, 0(%1)" : "=r" (val) : "r" (addr));
81 	return val;
82 }
83 
84 #ifdef CONFIG_64BIT
85 #define __raw_readq __raw_readq
86 static inline u64 __raw_readq(const volatile void __iomem *addr)
87 {
88 	u64 val;
89 
90 	asm volatile("ld %0, 0(%1)" : "=r" (val) : "r" (addr));
91 	return val;
92 }
93 #endif
94 
95 /*
96  * Unordered I/O memory access primitives.  These are even more relaxed than
97  * the relaxed versions, as they don't even order accesses between successive
98  * operations to the I/O regions.
99  */
100 #define readb_cpu(c)		({ u8  __r = __raw_readb(c); __r; })
101 #define readw_cpu(c)		({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; })
102 #define readl_cpu(c)		({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
103 
104 #define writeb_cpu(v,c)		((void)__raw_writeb((v),(c)))
105 #define writew_cpu(v,c)		((void)__raw_writew((__force u16)cpu_to_le16(v),(c)))
106 #define writel_cpu(v,c)		((void)__raw_writel((__force u32)cpu_to_le32(v),(c)))
107 
108 #ifdef CONFIG_64BIT
109 #define readq_cpu(c)		({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; })
110 #define writeq_cpu(v,c)		((void)__raw_writeq((__force u64)cpu_to_le64(v),(c)))
111 #endif
112 
113 /*
114  * Relaxed I/O memory access primitives. These follow the Device memory
115  * ordering rules but do not guarantee any ordering relative to Normal memory
116  * accesses.  These are defined to order the indicated access (either a read or
117  * write) with all other I/O memory accesses. Since the platform specification
118  * defines that all I/O regions are strongly ordered on channel 2, no explicit
119  * fences are required to enforce this ordering.
120  */
121 /* FIXME: These are now the same as asm-generic */
122 #define __io_rbr()		do {} while (0)
123 #define __io_rar()		do {} while (0)
124 #define __io_rbw()		do {} while (0)
125 #define __io_raw()		do {} while (0)
126 
127 #define readb_relaxed(c)	({ u8  __v; __io_rbr(); __v = readb_cpu(c); __io_rar(); __v; })
128 #define readw_relaxed(c)	({ u16 __v; __io_rbr(); __v = readw_cpu(c); __io_rar(); __v; })
129 #define readl_relaxed(c)	({ u32 __v; __io_rbr(); __v = readl_cpu(c); __io_rar(); __v; })
130 
131 #define writeb_relaxed(v,c)	({ __io_rbw(); writeb_cpu((v),(c)); __io_raw(); })
132 #define writew_relaxed(v,c)	({ __io_rbw(); writew_cpu((v),(c)); __io_raw(); })
133 #define writel_relaxed(v,c)	({ __io_rbw(); writel_cpu((v),(c)); __io_raw(); })
134 
135 #ifdef CONFIG_64BIT
136 #define readq_relaxed(c)	({ u64 __v; __io_rbr(); __v = readq_cpu(c); __io_rar(); __v; })
137 #define writeq_relaxed(v,c)	({ __io_rbw(); writeq_cpu((v),(c)); __io_raw(); })
138 #endif
139 
140 /*
141  * I/O memory access primitives. Reads are ordered relative to any
142  * following Normal memory access. Writes are ordered relative to any prior
143  * Normal memory access.  The memory barriers here are necessary as RISC-V
144  * doesn't define any ordering between the memory space and the I/O space.
145  */
146 #define __io_br()	do {} while (0)
147 #define __io_ar(v)	__asm__ __volatile__ ("fence i,r" : : : "memory");
148 #define __io_bw()	__asm__ __volatile__ ("fence w,o" : : : "memory");
149 #define __io_aw()	mmiowb_set_pending()
150 
151 #define readb(c)	({ u8  __v; __io_br(); __v = readb_cpu(c); __io_ar(__v); __v; })
152 #define readw(c)	({ u16 __v; __io_br(); __v = readw_cpu(c); __io_ar(__v); __v; })
153 #define readl(c)	({ u32 __v; __io_br(); __v = readl_cpu(c); __io_ar(__v); __v; })
154 
155 #define writeb(v,c)	({ __io_bw(); writeb_cpu((v),(c)); __io_aw(); })
156 #define writew(v,c)	({ __io_bw(); writew_cpu((v),(c)); __io_aw(); })
157 #define writel(v,c)	({ __io_bw(); writel_cpu((v),(c)); __io_aw(); })
158 
159 #ifdef CONFIG_64BIT
160 #define readq(c)	({ u64 __v; __io_br(); __v = readq_cpu(c); __io_ar(__v); __v; })
161 #define writeq(v,c)	({ __io_bw(); writeq_cpu((v),(c)); __io_aw(); })
162 #endif
163 
164 /*
165  * Emulation routines for the port-mapped IO space used by some PCI drivers.
166  * These are defined as being "fully synchronous", but also "not guaranteed to
167  * be fully ordered with respect to other memory and I/O operations".  We're
168  * going to be on the safe side here and just make them:
169  *  - Fully ordered WRT each other, by bracketing them with two fences.  The
170  *    outer set contains both I/O so inX is ordered with outX, while the inner just
171  *    needs the type of the access (I for inX and O for outX).
172  *  - Ordered in the same manner as readX/writeX WRT memory by subsuming their
173  *    fences.
174  *  - Ordered WRT timer reads, so udelay and friends don't get elided by the
175  *    implementation.
176  * Note that there is no way to actually enforce that outX is a non-posted
177  * operation on RISC-V, but hopefully the timer ordering constraint is
178  * sufficient to ensure this works sanely on controllers that support I/O
179  * writes.
180  */
181 #define __io_pbr()	__asm__ __volatile__ ("fence io,i"  : : : "memory");
182 #define __io_par(v)	__asm__ __volatile__ ("fence i,ior" : : : "memory");
183 #define __io_pbw()	__asm__ __volatile__ ("fence iow,o" : : : "memory");
184 #define __io_paw()	__asm__ __volatile__ ("fence o,io"  : : : "memory");
185 
186 #define inb(c)		({ u8  __v; __io_pbr(); __v = readb_cpu((void*)(PCI_IOBASE + (c))); __io_par(__v); __v; })
187 #define inw(c)		({ u16 __v; __io_pbr(); __v = readw_cpu((void*)(PCI_IOBASE + (c))); __io_par(__v); __v; })
188 #define inl(c)		({ u32 __v; __io_pbr(); __v = readl_cpu((void*)(PCI_IOBASE + (c))); __io_par(__v); __v; })
189 
190 #define outb(v,c)	({ __io_pbw(); writeb_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
191 #define outw(v,c)	({ __io_pbw(); writew_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
192 #define outl(v,c)	({ __io_pbw(); writel_cpu((v),(void*)(PCI_IOBASE + (c))); __io_paw(); })
193 
194 #ifdef CONFIG_64BIT
195 #define inq(c)		({ u64 __v; __io_pbr(); __v = readq_cpu((void*)(c)); __io_par(__v); __v; })
196 #define outq(v,c)	({ __io_pbw(); writeq_cpu((v),(void*)(c)); __io_paw(); })
197 #endif
198 
199 /*
200  * Accesses from a single hart to a single I/O address must be ordered.  This
201  * allows us to use the raw read macros, but we still need to fence before and
202  * after the block to ensure ordering WRT other macros.  These are defined to
203  * perform host-endian accesses so we use __raw instead of __cpu.
204  */
205 #define __io_reads_ins(port, ctype, len, bfence, afence)			\
206 	static inline void __ ## port ## len(const volatile void __iomem *addr,	\
207 					     void *buffer,			\
208 					     unsigned int count)		\
209 	{									\
210 		bfence;								\
211 		if (count) {							\
212 			ctype *buf = buffer;					\
213 										\
214 			do {							\
215 				ctype x = __raw_read ## len(addr);		\
216 				*buf++ = x;					\
217 			} while (--count);					\
218 		}								\
219 		afence;								\
220 	}
221 
222 #define __io_writes_outs(port, ctype, len, bfence, afence)			\
223 	static inline void __ ## port ## len(volatile void __iomem *addr,	\
224 					     const void *buffer,		\
225 					     unsigned int count)		\
226 	{									\
227 		bfence;								\
228 		if (count) {							\
229 			const ctype *buf = buffer;				\
230 										\
231 			do {							\
232 				__raw_write ## len(*buf++, addr);		\
233 			} while (--count);					\
234 		}								\
235 		afence;								\
236 	}
237 
238 __io_reads_ins(reads,  u8, b, __io_br(), __io_ar(addr))
239 __io_reads_ins(reads, u16, w, __io_br(), __io_ar(addr))
240 __io_reads_ins(reads, u32, l, __io_br(), __io_ar(addr))
241 #define readsb(addr, buffer, count) __readsb(addr, buffer, count)
242 #define readsw(addr, buffer, count) __readsw(addr, buffer, count)
243 #define readsl(addr, buffer, count) __readsl(addr, buffer, count)
244 
245 __io_reads_ins(ins,  u8, b, __io_pbr(), __io_par(addr))
246 __io_reads_ins(ins, u16, w, __io_pbr(), __io_par(addr))
247 __io_reads_ins(ins, u32, l, __io_pbr(), __io_par(addr))
248 #define insb(addr, buffer, count) __insb((void __iomem *)(long)addr, buffer, count)
249 #define insw(addr, buffer, count) __insw((void __iomem *)(long)addr, buffer, count)
250 #define insl(addr, buffer, count) __insl((void __iomem *)(long)addr, buffer, count)
251 
252 __io_writes_outs(writes,  u8, b, __io_bw(), __io_aw())
253 __io_writes_outs(writes, u16, w, __io_bw(), __io_aw())
254 __io_writes_outs(writes, u32, l, __io_bw(), __io_aw())
255 #define writesb(addr, buffer, count) __writesb(addr, buffer, count)
256 #define writesw(addr, buffer, count) __writesw(addr, buffer, count)
257 #define writesl(addr, buffer, count) __writesl(addr, buffer, count)
258 
259 __io_writes_outs(outs,  u8, b, __io_pbw(), __io_paw())
260 __io_writes_outs(outs, u16, w, __io_pbw(), __io_paw())
261 __io_writes_outs(outs, u32, l, __io_pbw(), __io_paw())
262 #define outsb(addr, buffer, count) __outsb((void __iomem *)(long)addr, buffer, count)
263 #define outsw(addr, buffer, count) __outsw((void __iomem *)(long)addr, buffer, count)
264 #define outsl(addr, buffer, count) __outsl((void __iomem *)(long)addr, buffer, count)
265 
266 #ifdef CONFIG_64BIT
267 __io_reads_ins(reads, u64, q, __io_br(), __io_ar(addr))
268 #define readsq(addr, buffer, count) __readsq(addr, buffer, count)
269 
270 __io_reads_ins(ins, u64, q, __io_pbr(), __io_par(addr))
271 #define insq(addr, buffer, count) __insq((void __iomem *)addr, buffer, count)
272 
273 __io_writes_outs(writes, u64, q, __io_bw(), __io_aw())
274 #define writesq(addr, buffer, count) __writesq(addr, buffer, count)
275 
276 __io_writes_outs(outs, u64, q, __io_pbr(), __io_paw())
277 #define outsq(addr, buffer, count) __outsq((void __iomem *)addr, buffer, count)
278 #endif
279 
280 #include <asm-generic/io.h>
281 
282 #endif /* _ASM_RISCV_IO_H */
283