xref: /openbmc/linux/arch/arm/include/asm/io.h (revision 77d84ff8)
1 /*
2  *  arch/arm/include/asm/io.h
3  *
4  *  Copyright (C) 1996-2000 Russell King
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * Modifications:
11  *  16-Sep-1996	RMK	Inlined the inx/outx functions & optimised for both
12  *			constant addresses and variable addresses.
13  *  04-Dec-1997	RMK	Moved a lot of this stuff to the new architecture
14  *			specific IO header files.
15  *  27-Mar-1999	PJB	Second parameter of memcpy_toio is const..
16  *  04-Apr-1999	PJB	Added check_signature.
17  *  12-Dec-1999	RMK	More cleanups
18  *  18-Jun-2000 RMK	Removed virt_to_* and friends definitions
19  *  05-Oct-2004 BJD     Moved memory string functions to use void __iomem
20  */
21 #ifndef __ASM_ARM_IO_H
22 #define __ASM_ARM_IO_H
23 
24 #ifdef __KERNEL__
25 
26 #include <linux/types.h>
27 #include <linux/blk_types.h>
28 #include <asm/byteorder.h>
29 #include <asm/memory.h>
30 #include <asm-generic/pci_iomap.h>
31 #include <xen/xen.h>
32 
33 /*
34  * ISA I/O bus memory addresses are 1:1 with the physical address.
35  */
36 #define isa_virt_to_bus virt_to_phys
37 #define isa_page_to_bus page_to_phys
38 #define isa_bus_to_virt phys_to_virt
39 
40 /*
41  * Generic IO read/write.  These perform native-endian accesses.  Note
42  * that some architectures will want to re-define __raw_{read,write}w.
43  */
44 extern void __raw_writesb(void __iomem *addr, const void *data, int bytelen);
45 extern void __raw_writesw(void __iomem *addr, const void *data, int wordlen);
46 extern void __raw_writesl(void __iomem *addr, const void *data, int longlen);
47 
48 extern void __raw_readsb(const void __iomem *addr, void *data, int bytelen);
49 extern void __raw_readsw(const void __iomem *addr, void *data, int wordlen);
50 extern void __raw_readsl(const void __iomem *addr, void *data, int longlen);
51 
52 #if __LINUX_ARM_ARCH__ < 6
53 /*
54  * Half-word accesses are problematic with RiscPC due to limitations of
55  * the bus. Rather than special-case the machine, just let the compiler
56  * generate the access for CPUs prior to ARMv6.
57  */
58 #define __raw_readw(a)         (__chk_io_ptr(a), *(volatile unsigned short __force *)(a))
59 #define __raw_writew(v,a)      ((void)(__chk_io_ptr(a), *(volatile unsigned short __force *)(a) = (v)))
60 #else
61 /*
62  * When running under a hypervisor, we want to avoid I/O accesses with
63  * writeback addressing modes as these incur a significant performance
64  * overhead (the address generation must be emulated in software).
65  */
66 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
67 {
68 	asm volatile("strh %1, %0"
69 		     : "+Q" (*(volatile u16 __force *)addr)
70 		     : "r" (val));
71 }
72 
73 static inline u16 __raw_readw(const volatile void __iomem *addr)
74 {
75 	u16 val;
76 	asm volatile("ldrh %1, %0"
77 		     : "+Q" (*(volatile u16 __force *)addr),
78 		       "=r" (val));
79 	return val;
80 }
81 #endif
82 
83 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
84 {
85 	asm volatile("strb %1, %0"
86 		     : "+Qo" (*(volatile u8 __force *)addr)
87 		     : "r" (val));
88 }
89 
90 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
91 {
92 	asm volatile("str %1, %0"
93 		     : "+Qo" (*(volatile u32 __force *)addr)
94 		     : "r" (val));
95 }
96 
97 static inline u8 __raw_readb(const volatile void __iomem *addr)
98 {
99 	u8 val;
100 	asm volatile("ldrb %1, %0"
101 		     : "+Qo" (*(volatile u8 __force *)addr),
102 		       "=r" (val));
103 	return val;
104 }
105 
106 static inline u32 __raw_readl(const volatile void __iomem *addr)
107 {
108 	u32 val;
109 	asm volatile("ldr %1, %0"
110 		     : "+Qo" (*(volatile u32 __force *)addr),
111 		       "=r" (val));
112 	return val;
113 }
114 
115 /*
116  * Architecture ioremap implementation.
117  */
118 #define MT_DEVICE		0
119 #define MT_DEVICE_NONSHARED	1
120 #define MT_DEVICE_CACHED	2
121 #define MT_DEVICE_WC		3
122 /*
123  * types 4 onwards can be found in asm/mach/map.h and are undefined
124  * for ioremap
125  */
126 
127 /*
128  * __arm_ioremap takes CPU physical address.
129  * __arm_ioremap_pfn takes a Page Frame Number and an offset into that page
130  * The _caller variety takes a __builtin_return_address(0) value for
131  * /proc/vmalloc to use - and should only be used in non-inline functions.
132  */
133 extern void __iomem *__arm_ioremap_pfn_caller(unsigned long, unsigned long,
134 	size_t, unsigned int, void *);
135 extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
136 	void *);
137 
138 extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
139 extern void __iomem *__arm_ioremap(phys_addr_t, size_t, unsigned int);
140 extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
141 extern void __iounmap(volatile void __iomem *addr);
142 extern void __arm_iounmap(volatile void __iomem *addr);
143 
144 extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
145 	unsigned int, void *);
146 extern void (*arch_iounmap)(volatile void __iomem *);
147 
148 /*
149  * Bad read/write accesses...
150  */
151 extern void __readwrite_bug(const char *fn);
152 
153 /*
154  * A typesafe __io() helper
155  */
156 static inline void __iomem *__typesafe_io(unsigned long addr)
157 {
158 	return (void __iomem *)addr;
159 }
160 
161 #define IOMEM(x)	((void __force __iomem *)(x))
162 
163 /* IO barriers */
164 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
165 #include <asm/barrier.h>
166 #define __iormb()		rmb()
167 #define __iowmb()		wmb()
168 #else
169 #define __iormb()		do { } while (0)
170 #define __iowmb()		do { } while (0)
171 #endif
172 
173 /* PCI fixed i/o mapping */
174 #define PCI_IO_VIRT_BASE	0xfee00000
175 
176 extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
177 
178 /*
179  * Now, pick up the machine-defined IO definitions
180  */
181 #ifdef CONFIG_NEED_MACH_IO_H
182 #include <mach/io.h>
183 #elif defined(CONFIG_PCI)
184 #define IO_SPACE_LIMIT	((resource_size_t)0xfffff)
185 #define __io(a)		__typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
186 #else
187 #define __io(a)		__typesafe_io((a) & IO_SPACE_LIMIT)
188 #endif
189 
190 /*
191  * This is the limit of PC card/PCI/ISA IO space, which is by default
192  * 64K if we have PC card, PCI or ISA support.  Otherwise, default to
193  * zero to prevent ISA/PCI drivers claiming IO space (and potentially
194  * oopsing.)
195  *
196  * Only set this larger if you really need inb() et.al. to operate over
197  * a larger address space.  Note that SOC_COMMON ioremaps each sockets
198  * IO space area, and so inb() et.al. must be defined to operate as per
199  * readb() et.al. on such platforms.
200  */
201 #ifndef IO_SPACE_LIMIT
202 #if defined(CONFIG_PCMCIA_SOC_COMMON) || defined(CONFIG_PCMCIA_SOC_COMMON_MODULE)
203 #define IO_SPACE_LIMIT ((resource_size_t)0xffffffff)
204 #elif defined(CONFIG_PCI) || defined(CONFIG_ISA) || defined(CONFIG_PCCARD)
205 #define IO_SPACE_LIMIT ((resource_size_t)0xffff)
206 #else
207 #define IO_SPACE_LIMIT ((resource_size_t)0)
208 #endif
209 #endif
210 
211 /*
212  *  IO port access primitives
213  *  -------------------------
214  *
215  * The ARM doesn't have special IO access instructions; all IO is memory
216  * mapped.  Note that these are defined to perform little endian accesses
217  * only.  Their primary purpose is to access PCI and ISA peripherals.
218  *
219  * Note that for a big endian machine, this implies that the following
220  * big endian mode connectivity is in place, as described by numerous
221  * ARM documents:
222  *
223  *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
224  *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
225  *
226  * The machine specific io.h include defines __io to translate an "IO"
227  * address to a memory address.
228  *
229  * Note that we prevent GCC re-ordering or caching values in expressions
230  * by introducing sequence points into the in*() definitions.  Note that
231  * __raw_* do not guarantee this behaviour.
232  *
233  * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
234  */
235 #ifdef __io
236 #define outb(v,p)	({ __iowmb(); __raw_writeb(v,__io(p)); })
237 #define outw(v,p)	({ __iowmb(); __raw_writew((__force __u16) \
238 					cpu_to_le16(v),__io(p)); })
239 #define outl(v,p)	({ __iowmb(); __raw_writel((__force __u32) \
240 					cpu_to_le32(v),__io(p)); })
241 
242 #define inb(p)	({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
243 #define inw(p)	({ __u16 __v = le16_to_cpu((__force __le16) \
244 			__raw_readw(__io(p))); __iormb(); __v; })
245 #define inl(p)	({ __u32 __v = le32_to_cpu((__force __le32) \
246 			__raw_readl(__io(p))); __iormb(); __v; })
247 
248 #define outsb(p,d,l)		__raw_writesb(__io(p),d,l)
249 #define outsw(p,d,l)		__raw_writesw(__io(p),d,l)
250 #define outsl(p,d,l)		__raw_writesl(__io(p),d,l)
251 
252 #define insb(p,d,l)		__raw_readsb(__io(p),d,l)
253 #define insw(p,d,l)		__raw_readsw(__io(p),d,l)
254 #define insl(p,d,l)		__raw_readsl(__io(p),d,l)
255 #endif
256 
257 #define outb_p(val,port)	outb((val),(port))
258 #define outw_p(val,port)	outw((val),(port))
259 #define outl_p(val,port)	outl((val),(port))
260 #define inb_p(port)		inb((port))
261 #define inw_p(port)		inw((port))
262 #define inl_p(port)		inl((port))
263 
264 #define outsb_p(port,from,len)	outsb(port,from,len)
265 #define outsw_p(port,from,len)	outsw(port,from,len)
266 #define outsl_p(port,from,len)	outsl(port,from,len)
267 #define insb_p(port,to,len)	insb(port,to,len)
268 #define insw_p(port,to,len)	insw(port,to,len)
269 #define insl_p(port,to,len)	insl(port,to,len)
270 
271 /*
272  * String version of IO memory access ops:
273  */
274 extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
275 extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
276 extern void _memset_io(volatile void __iomem *, int, size_t);
277 
278 #define mmiowb()
279 
280 /*
281  *  Memory access primitives
282  *  ------------------------
283  *
284  * These perform PCI memory accesses via an ioremap region.  They don't
285  * take an address as such, but a cookie.
286  *
287  * Again, this are defined to perform little endian accesses.  See the
288  * IO port primitives for more information.
289  */
290 #ifndef readl
291 #define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
292 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
293 					__raw_readw(c)); __r; })
294 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
295 					__raw_readl(c)); __r; })
296 
297 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
298 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
299 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
300 
301 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
302 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
303 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
304 
305 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
306 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
307 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
308 
309 #define readsb(p,d,l)		__raw_readsb(p,d,l)
310 #define readsw(p,d,l)		__raw_readsw(p,d,l)
311 #define readsl(p,d,l)		__raw_readsl(p,d,l)
312 
313 #define writesb(p,d,l)		__raw_writesb(p,d,l)
314 #define writesw(p,d,l)		__raw_writesw(p,d,l)
315 #define writesl(p,d,l)		__raw_writesl(p,d,l)
316 
317 #define memset_io(c,v,l)	_memset_io(c,(v),(l))
318 #define memcpy_fromio(a,c,l)	_memcpy_fromio((a),c,(l))
319 #define memcpy_toio(c,a,l)	_memcpy_toio(c,(a),(l))
320 
321 #endif	/* readl */
322 
323 /*
324  * ioremap and friends.
325  *
326  * ioremap takes a PCI memory address, as specified in
327  * Documentation/io-mapping.txt.
328  *
329  */
330 #define ioremap(cookie,size)		__arm_ioremap((cookie), (size), MT_DEVICE)
331 #define ioremap_nocache(cookie,size)	__arm_ioremap((cookie), (size), MT_DEVICE)
332 #define ioremap_cached(cookie,size)	__arm_ioremap((cookie), (size), MT_DEVICE_CACHED)
333 #define ioremap_wc(cookie,size)		__arm_ioremap((cookie), (size), MT_DEVICE_WC)
334 #define iounmap				__arm_iounmap
335 
336 /*
337  * io{read,write}{8,16,32} macros
338  */
339 #ifndef ioread8
340 #define ioread8(p)	({ unsigned int __v = __raw_readb(p); __iormb(); __v; })
341 #define ioread16(p)	({ unsigned int __v = le16_to_cpu((__force __le16)__raw_readw(p)); __iormb(); __v; })
342 #define ioread32(p)	({ unsigned int __v = le32_to_cpu((__force __le32)__raw_readl(p)); __iormb(); __v; })
343 
344 #define ioread16be(p)	({ unsigned int __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
345 #define ioread32be(p)	({ unsigned int __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
346 
347 #define iowrite8(v,p)	({ __iowmb(); __raw_writeb(v, p); })
348 #define iowrite16(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_le16(v), p); })
349 #define iowrite32(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_le32(v), p); })
350 
351 #define iowrite16be(v,p) ({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
352 #define iowrite32be(v,p) ({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
353 
354 #define ioread8_rep(p,d,c)	__raw_readsb(p,d,c)
355 #define ioread16_rep(p,d,c)	__raw_readsw(p,d,c)
356 #define ioread32_rep(p,d,c)	__raw_readsl(p,d,c)
357 
358 #define iowrite8_rep(p,s,c)	__raw_writesb(p,s,c)
359 #define iowrite16_rep(p,s,c)	__raw_writesw(p,s,c)
360 #define iowrite32_rep(p,s,c)	__raw_writesl(p,s,c)
361 
362 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
363 extern void ioport_unmap(void __iomem *addr);
364 #endif
365 
366 struct pci_dev;
367 
368 extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
369 
370 /*
371  * can the hardware map this into one segment or not, given no other
372  * constraints.
373  */
374 #define BIOVEC_MERGEABLE(vec1, vec2)	\
375 	((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
376 
377 struct bio_vec;
378 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
379 				      const struct bio_vec *vec2);
380 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
381 	(__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&				\
382 	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
383 
384 #ifdef CONFIG_MMU
385 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
386 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
387 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
388 extern int devmem_is_allowed(unsigned long pfn);
389 #endif
390 
391 /*
392  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
393  * access
394  */
395 #define xlate_dev_mem_ptr(p)	__va(p)
396 
397 /*
398  * Convert a virtual cached pointer to an uncached pointer
399  */
400 #define xlate_dev_kmem_ptr(p)	p
401 
402 /*
403  * Register ISA memory and port locations for glibc iopl/inb/outb
404  * emulation.
405  */
406 extern void register_isa_ports(unsigned int mmio, unsigned int io,
407 			       unsigned int io_shift);
408 
409 #endif	/* __KERNEL__ */
410 #endif	/* __ASM_ARM_IO_H */
411