xref: /openbmc/u-boot/arch/arc/include/asm/io.h (revision baefb63a)
1 /*
2  * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #ifndef __ASM_ARC_IO_H
8 #define __ASM_ARC_IO_H
9 
10 #include <linux/types.h>
11 #include <asm/byteorder.h>
12 
13 #ifdef CONFIG_ISA_ARCV2
14 
15 /*
16  * ARCv2 based HS38 cores are in-order issue, but still weakly ordered
17  * due to micro-arch buffering/queuing of load/store, cache hit vs. miss ...
18  *
19  * Explicit barrier provided by DMB instruction
20  *  - Operand supports fine grained load/store/load+store semantics
21  *  - Ensures that selected memory operation issued before it will complete
22  *    before any subsequent memory operation of same type
23  *  - DMB guarantees SMP as well as local barrier semantics
24  *    (asm-generic/barrier.h ensures sane smp_*mb if not defined here, i.e.
25  *    UP: barrier(), SMP: smp_*mb == *mb)
26  *  - DSYNC provides DMB+completion_of_cache_bpu_maintenance_ops hence not needed
27  *    in the general case. Plus it only provides full barrier.
28  */
29 
30 #define mb()	asm volatile("dmb 3\n" : : : "memory")
31 #define rmb()	asm volatile("dmb 1\n" : : : "memory")
32 #define wmb()	asm volatile("dmb 2\n" : : : "memory")
33 
34 #else
35 
36 /*
37  * ARCompact based cores (ARC700) only have SYNC instruction which is super
38  * heavy weight as it flushes the pipeline as well.
39  * There are no real SMP implementations of such cores.
40  */
41 
42 #define mb()	asm volatile("sync\n" : : : "memory")
43 #endif
44 
45 #ifdef CONFIG_ISA_ARCV2
46 #define __iormb()		rmb()
47 #define __iowmb()		wmb()
48 #else
49 #define __iormb()		do { } while (0)
50 #define __iowmb()		do { } while (0)
51 #endif
52 
53 static inline void sync(void)
54 {
55 	/* Not yet implemented */
56 }
57 
58 static inline u8 __raw_readb(const volatile void __iomem *addr)
59 {
60 	u8 b;
61 
62 	__asm__ __volatile__("ldb%U1	%0, %1\n"
63 			     : "=r" (b)
64 			     : "m" (*(volatile u8 __force *)addr)
65 			     : "memory");
66 	return b;
67 }
68 
69 static inline u16 __raw_readw(const volatile void __iomem *addr)
70 {
71 	u16 s;
72 
73 	__asm__ __volatile__("ldw%U1	%0, %1\n"
74 			     : "=r" (s)
75 			     : "m" (*(volatile u16 __force *)addr)
76 			     : "memory");
77 	return s;
78 }
79 
80 static inline u32 __raw_readl(const volatile void __iomem *addr)
81 {
82 	u32 w;
83 
84 	__asm__ __volatile__("ld%U1	%0, %1\n"
85 			     : "=r" (w)
86 			     : "m" (*(volatile u32 __force *)addr)
87 			     : "memory");
88 	return w;
89 }
90 
91 static inline void __raw_writeb(u8 b, volatile void __iomem *addr)
92 {
93 	__asm__ __volatile__("stb%U1	%0, %1\n"
94 			     :
95 			     : "r" (b), "m" (*(volatile u8 __force *)addr)
96 			     : "memory");
97 }
98 
99 static inline void __raw_writew(u16 s, volatile void __iomem *addr)
100 {
101 	__asm__ __volatile__("stw%U1	%0, %1\n"
102 			     :
103 			     : "r" (s), "m" (*(volatile u16 __force *)addr)
104 			     : "memory");
105 }
106 
107 static inline void __raw_writel(u32 w, volatile void __iomem *addr)
108 {
109 	__asm__ __volatile__("st%U1	%0, %1\n"
110 			     :
111 			     : "r" (w), "m" (*(volatile u32 __force *)addr)
112 			     : "memory");
113 }
114 
115 static inline int __raw_readsb(unsigned int addr, void *data, int bytelen)
116 {
117 	__asm__ __volatile__ ("1:ld.di	r8, [r0]\n"
118 			      "sub.f	r2, r2, 1\n"
119 			      "bnz.d	1b\n"
120 			      "stb.ab	r8, [r1, 1]\n"
121 			      :
122 			      : "r" (addr), "r" (data), "r" (bytelen)
123 			      : "r8");
124 	return bytelen;
125 }
126 
127 static inline int __raw_readsw(unsigned int addr, void *data, int wordlen)
128 {
129 	__asm__ __volatile__ ("1:ld.di	r8, [r0]\n"
130 			      "sub.f	r2, r2, 1\n"
131 			      "bnz.d	1b\n"
132 			      "stw.ab	r8, [r1, 2]\n"
133 			      :
134 			      : "r" (addr), "r" (data), "r" (wordlen)
135 			      : "r8");
136 	return wordlen;
137 }
138 
139 static inline int __raw_readsl(unsigned int addr, void *data, int longlen)
140 {
141 	__asm__ __volatile__ ("1:ld.di	r8, [r0]\n"
142 			      "sub.f	r2, r2, 1\n"
143 			      "bnz.d	1b\n"
144 			      "st.ab	r8, [r1, 4]\n"
145 			      :
146 			      : "r" (addr), "r" (data), "r" (longlen)
147 			      : "r8");
148 	return longlen;
149 }
150 
151 static inline int __raw_writesb(unsigned int addr, void *data, int bytelen)
152 {
153 	__asm__ __volatile__ ("1:ldb.ab	r8, [r1, 1]\n"
154 			      "sub.f	r2, r2, 1\n"
155 			      "bnz.d	1b\n"
156 			      "st.di	r8, [r0, 0]\n"
157 			      :
158 			      : "r" (addr), "r" (data), "r" (bytelen)
159 			      : "r8");
160 	return bytelen;
161 }
162 
163 static inline int __raw_writesw(unsigned int addr, void *data, int wordlen)
164 {
165 	__asm__ __volatile__ ("1:ldw.ab	r8, [r1, 2]\n"
166 			      "sub.f	r2, r2, 1\n"
167 			      "bnz.d	1b\n"
168 			      "st.ab.di	r8, [r0, 0]\n"
169 			      :
170 			      : "r" (addr), "r" (data), "r" (wordlen)
171 			      : "r8");
172 	return wordlen;
173 }
174 
175 static inline int __raw_writesl(unsigned int addr, void *data, int longlen)
176 {
177 	__asm__ __volatile__ ("1:ld.ab	r8, [r1, 4]\n"
178 			      "sub.f	r2, r2, 1\n"
179 			      "bnz.d	1b\n"
180 			      "st.ab.di	r8, [r0, 0]\n"
181 			      :
182 			      : "r" (addr), "r" (data), "r" (longlen)
183 			      : "r8");
184 	return longlen;
185 }
186 
187 /*
188  * MMIO can also get buffered/optimized in micro-arch, so barriers needed
189  * Based on ARM model for the typical use case
190  *
191  *	<ST [DMA buffer]>
192  *	<writel MMIO "go" reg>
193  *  or:
194  *	<readl MMIO "status" reg>
195  *	<LD [DMA buffer]>
196  *
197  * http://lkml.kernel.org/r/20150622133656.GG1583@arm.com
198  */
199 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
200 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
201 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
202 
203 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
204 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
205 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
206 
207 /*
208  * Relaxed API for drivers which can handle barrier ordering themselves
209  *
210  * Also these are defined to perform little endian accesses.
211  * To provide the typical device register semantics of fixed endian,
212  * swap the byte order for Big Endian
213  *
214  * http://lkml.kernel.org/r/201603100845.30602.arnd@arndb.de
215  */
216 #define readb_relaxed(c)	__raw_readb(c)
217 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
218 					__raw_readw(c)); __r; })
219 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
220 					__raw_readl(c)); __r; })
221 
222 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
223 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
224 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
225 
226 #define out_arch(type, endian, a, v)	__raw_write##type(cpu_to_##endian(v), a)
227 #define in_arch(type, endian, a)	endian##_to_cpu(__raw_read##type(a))
228 
229 #define out_le32(a, v)	out_arch(l, le32, a, v)
230 #define out_le16(a, v)	out_arch(w, le16, a, v)
231 
232 #define in_le32(a)	in_arch(l, le32, a)
233 #define in_le16(a)	in_arch(w, le16, a)
234 
235 #define out_be32(a, v)	out_arch(l, be32, a, v)
236 #define out_be16(a, v)	out_arch(w, be16, a, v)
237 
238 #define in_be32(a)	in_arch(l, be32, a)
239 #define in_be16(a)	in_arch(w, be16, a)
240 
241 #define out_8(a, v)	__raw_writeb(v, a)
242 #define in_8(a)		__raw_readb(a)
243 
244 /*
245  * Clear and set bits in one shot. These macros can be used to clear and
246  * set multiple bits in a register using a single call. These macros can
247  * also be used to set a multiple-bit bit pattern using a mask, by
248  * specifying the mask in the 'clear' parameter and the new bit pattern
249  * in the 'set' parameter.
250  */
251 
252 #define clrbits(type, addr, clear) \
253 	out_##type((addr), in_##type(addr) & ~(clear))
254 
255 #define setbits(type, addr, set) \
256 	out_##type((addr), in_##type(addr) | (set))
257 
258 #define clrsetbits(type, addr, clear, set) \
259 	out_##type((addr), (in_##type(addr) & ~(clear)) | (set))
260 
261 #define clrbits_be32(addr, clear) clrbits(be32, addr, clear)
262 #define setbits_be32(addr, set) setbits(be32, addr, set)
263 #define clrsetbits_be32(addr, clear, set) clrsetbits(be32, addr, clear, set)
264 
265 #define clrbits_le32(addr, clear) clrbits(le32, addr, clear)
266 #define setbits_le32(addr, set) setbits(le32, addr, set)
267 #define clrsetbits_le32(addr, clear, set) clrsetbits(le32, addr, clear, set)
268 
269 #define clrbits_be16(addr, clear) clrbits(be16, addr, clear)
270 #define setbits_be16(addr, set) setbits(be16, addr, set)
271 #define clrsetbits_be16(addr, clear, set) clrsetbits(be16, addr, clear, set)
272 
273 #define clrbits_le16(addr, clear) clrbits(le16, addr, clear)
274 #define setbits_le16(addr, set) setbits(le16, addr, set)
275 #define clrsetbits_le16(addr, clear, set) clrsetbits(le16, addr, clear, set)
276 
277 #define clrbits_8(addr, clear) clrbits(8, addr, clear)
278 #define setbits_8(addr, set) setbits(8, addr, set)
279 #define clrsetbits_8(addr, clear, set) clrsetbits(8, addr, clear, set)
280 
281 #include <asm-generic/io.h>
282 
283 #endif	/* __ASM_ARC_IO_H */
284