xref: /linux/arch/arm/include/asm/io.h (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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  * Atomic MMIO-wide IO modify
42  */
43 extern void atomic_io_modify(void __iomem *reg, u32 mask, u32 set);
44 extern void atomic_io_modify_relaxed(void __iomem *reg, u32 mask, u32 set);
45 
46 /*
47  * Generic IO read/write.  These perform native-endian accesses.  Note
48  * that some architectures will want to re-define __raw_{read,write}w.
49  */
50 void __raw_writesb(volatile void __iomem *addr, const void *data, int bytelen);
51 void __raw_writesw(volatile void __iomem *addr, const void *data, int wordlen);
52 void __raw_writesl(volatile void __iomem *addr, const void *data, int longlen);
53 
54 void __raw_readsb(const volatile void __iomem *addr, void *data, int bytelen);
55 void __raw_readsw(const volatile void __iomem *addr, void *data, int wordlen);
56 void __raw_readsl(const volatile void __iomem *addr, void *data, int longlen);
57 
58 #if __LINUX_ARM_ARCH__ < 6
59 /*
60  * Half-word accesses are problematic with RiscPC due to limitations of
61  * the bus. Rather than special-case the machine, just let the compiler
62  * generate the access for CPUs prior to ARMv6.
63  */
64 #define __raw_readw(a)         (__chk_io_ptr(a), *(volatile unsigned short __force *)(a))
65 #define __raw_writew(v,a)      ((void)(__chk_io_ptr(a), *(volatile unsigned short __force *)(a) = (v)))
66 #else
67 /*
68  * When running under a hypervisor, we want to avoid I/O accesses with
69  * writeback addressing modes as these incur a significant performance
70  * overhead (the address generation must be emulated in software).
71  */
72 #define __raw_writew __raw_writew
73 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
74 {
75 	asm volatile("strh %1, %0"
76 		     : "+Q" (*(volatile u16 __force *)addr)
77 		     : "r" (val));
78 }
79 
80 #define __raw_readw __raw_readw
81 static inline u16 __raw_readw(const volatile void __iomem *addr)
82 {
83 	u16 val;
84 	asm volatile("ldrh %1, %0"
85 		     : "+Q" (*(volatile u16 __force *)addr),
86 		       "=r" (val));
87 	return val;
88 }
89 #endif
90 
91 #define __raw_writeb __raw_writeb
92 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
93 {
94 	asm volatile("strb %1, %0"
95 		     : "+Qo" (*(volatile u8 __force *)addr)
96 		     : "r" (val));
97 }
98 
99 #define __raw_writel __raw_writel
100 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
101 {
102 	asm volatile("str %1, %0"
103 		     : "+Qo" (*(volatile u32 __force *)addr)
104 		     : "r" (val));
105 }
106 
107 #define __raw_readb __raw_readb
108 static inline u8 __raw_readb(const volatile void __iomem *addr)
109 {
110 	u8 val;
111 	asm volatile("ldrb %1, %0"
112 		     : "+Qo" (*(volatile u8 __force *)addr),
113 		       "=r" (val));
114 	return val;
115 }
116 
117 #define __raw_readl __raw_readl
118 static inline u32 __raw_readl(const volatile void __iomem *addr)
119 {
120 	u32 val;
121 	asm volatile("ldr %1, %0"
122 		     : "+Qo" (*(volatile u32 __force *)addr),
123 		       "=r" (val));
124 	return val;
125 }
126 
127 /*
128  * Architecture ioremap implementation.
129  */
130 #define MT_DEVICE		0
131 #define MT_DEVICE_NONSHARED	1
132 #define MT_DEVICE_CACHED	2
133 #define MT_DEVICE_WC		3
134 /*
135  * types 4 onwards can be found in asm/mach/map.h and are undefined
136  * for ioremap
137  */
138 
139 /*
140  * __arm_ioremap takes CPU physical address.
141  * __arm_ioremap_pfn takes a Page Frame Number and an offset into that page
142  * The _caller variety takes a __builtin_return_address(0) value for
143  * /proc/vmalloc to use - and should only be used in non-inline functions.
144  */
145 extern void __iomem *__arm_ioremap_pfn_caller(unsigned long, unsigned long,
146 	size_t, unsigned int, void *);
147 extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
148 	void *);
149 
150 extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
151 extern void __iomem *__arm_ioremap(phys_addr_t, size_t, unsigned int);
152 extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
153 extern void __iounmap(volatile void __iomem *addr);
154 extern void __arm_iounmap(volatile void __iomem *addr);
155 
156 extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
157 	unsigned int, void *);
158 extern void (*arch_iounmap)(volatile void __iomem *);
159 
160 /*
161  * Bad read/write accesses...
162  */
163 extern void __readwrite_bug(const char *fn);
164 
165 /*
166  * A typesafe __io() helper
167  */
168 static inline void __iomem *__typesafe_io(unsigned long addr)
169 {
170 	return (void __iomem *)addr;
171 }
172 
173 #define IOMEM(x)	((void __force __iomem *)(x))
174 
175 /* IO barriers */
176 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
177 #include <asm/barrier.h>
178 #define __iormb()		rmb()
179 #define __iowmb()		wmb()
180 #else
181 #define __iormb()		do { } while (0)
182 #define __iowmb()		do { } while (0)
183 #endif
184 
185 /* PCI fixed i/o mapping */
186 #define PCI_IO_VIRT_BASE	0xfee00000
187 #define PCI_IOBASE		((void __iomem *)PCI_IO_VIRT_BASE)
188 
189 #if defined(CONFIG_PCI)
190 void pci_ioremap_set_mem_type(int mem_type);
191 #else
192 static inline void pci_ioremap_set_mem_type(int mem_type) {}
193 #endif
194 
195 extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
196 
197 /*
198  * Now, pick up the machine-defined IO definitions
199  */
200 #ifdef CONFIG_NEED_MACH_IO_H
201 #include <mach/io.h>
202 #elif defined(CONFIG_PCI)
203 #define IO_SPACE_LIMIT	((resource_size_t)0xfffff)
204 #define __io(a)		__typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
205 #else
206 #define __io(a)		__typesafe_io((a) & IO_SPACE_LIMIT)
207 #endif
208 
209 /*
210  * This is the limit of PC card/PCI/ISA IO space, which is by default
211  * 64K if we have PC card, PCI or ISA support.  Otherwise, default to
212  * zero to prevent ISA/PCI drivers claiming IO space (and potentially
213  * oopsing.)
214  *
215  * Only set this larger if you really need inb() et.al. to operate over
216  * a larger address space.  Note that SOC_COMMON ioremaps each sockets
217  * IO space area, and so inb() et.al. must be defined to operate as per
218  * readb() et.al. on such platforms.
219  */
220 #ifndef IO_SPACE_LIMIT
221 #if defined(CONFIG_PCMCIA_SOC_COMMON) || defined(CONFIG_PCMCIA_SOC_COMMON_MODULE)
222 #define IO_SPACE_LIMIT ((resource_size_t)0xffffffff)
223 #elif defined(CONFIG_PCI) || defined(CONFIG_ISA) || defined(CONFIG_PCCARD)
224 #define IO_SPACE_LIMIT ((resource_size_t)0xffff)
225 #else
226 #define IO_SPACE_LIMIT ((resource_size_t)0)
227 #endif
228 #endif
229 
230 /*
231  *  IO port access primitives
232  *  -------------------------
233  *
234  * The ARM doesn't have special IO access instructions; all IO is memory
235  * mapped.  Note that these are defined to perform little endian accesses
236  * only.  Their primary purpose is to access PCI and ISA peripherals.
237  *
238  * Note that for a big endian machine, this implies that the following
239  * big endian mode connectivity is in place, as described by numerous
240  * ARM documents:
241  *
242  *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
243  *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
244  *
245  * The machine specific io.h include defines __io to translate an "IO"
246  * address to a memory address.
247  *
248  * Note that we prevent GCC re-ordering or caching values in expressions
249  * by introducing sequence points into the in*() definitions.  Note that
250  * __raw_* do not guarantee this behaviour.
251  *
252  * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
253  */
254 #ifdef __io
255 #define outb(v,p)	({ __iowmb(); __raw_writeb(v,__io(p)); })
256 #define outw(v,p)	({ __iowmb(); __raw_writew((__force __u16) \
257 					cpu_to_le16(v),__io(p)); })
258 #define outl(v,p)	({ __iowmb(); __raw_writel((__force __u32) \
259 					cpu_to_le32(v),__io(p)); })
260 
261 #define inb(p)	({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
262 #define inw(p)	({ __u16 __v = le16_to_cpu((__force __le16) \
263 			__raw_readw(__io(p))); __iormb(); __v; })
264 #define inl(p)	({ __u32 __v = le32_to_cpu((__force __le32) \
265 			__raw_readl(__io(p))); __iormb(); __v; })
266 
267 #define outsb(p,d,l)		__raw_writesb(__io(p),d,l)
268 #define outsw(p,d,l)		__raw_writesw(__io(p),d,l)
269 #define outsl(p,d,l)		__raw_writesl(__io(p),d,l)
270 
271 #define insb(p,d,l)		__raw_readsb(__io(p),d,l)
272 #define insw(p,d,l)		__raw_readsw(__io(p),d,l)
273 #define insl(p,d,l)		__raw_readsl(__io(p),d,l)
274 #endif
275 
276 /*
277  * String version of IO memory access ops:
278  */
279 extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
280 extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
281 extern void _memset_io(volatile void __iomem *, int, size_t);
282 
283 #define mmiowb()
284 
285 /*
286  *  Memory access primitives
287  *  ------------------------
288  *
289  * These perform PCI memory accesses via an ioremap region.  They don't
290  * take an address as such, but a cookie.
291  *
292  * Again, this are defined to perform little endian accesses.  See the
293  * IO port primitives for more information.
294  */
295 #ifndef readl
296 #define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
297 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
298 					__raw_readw(c)); __r; })
299 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
300 					__raw_readl(c)); __r; })
301 
302 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
303 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
304 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
305 
306 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
307 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
308 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
309 
310 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
311 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
312 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
313 
314 #define readsb(p,d,l)		__raw_readsb(p,d,l)
315 #define readsw(p,d,l)		__raw_readsw(p,d,l)
316 #define readsl(p,d,l)		__raw_readsl(p,d,l)
317 
318 #define writesb(p,d,l)		__raw_writesb(p,d,l)
319 #define writesw(p,d,l)		__raw_writesw(p,d,l)
320 #define writesl(p,d,l)		__raw_writesl(p,d,l)
321 
322 #define memset_io(c,v,l)	_memset_io(c,(v),(l))
323 #define memcpy_fromio(a,c,l)	_memcpy_fromio((a),c,(l))
324 #define memcpy_toio(c,a,l)	_memcpy_toio(c,(a),(l))
325 
326 #endif	/* readl */
327 
328 /*
329  * ioremap and friends.
330  *
331  * ioremap takes a PCI memory address, as specified in
332  * Documentation/io-mapping.txt.
333  *
334  */
335 #define ioremap(cookie,size)		__arm_ioremap((cookie), (size), MT_DEVICE)
336 #define ioremap_nocache(cookie,size)	__arm_ioremap((cookie), (size), MT_DEVICE)
337 #define ioremap_cache(cookie,size)	__arm_ioremap((cookie), (size), MT_DEVICE_CACHED)
338 #define ioremap_wc(cookie,size)		__arm_ioremap((cookie), (size), MT_DEVICE_WC)
339 #define iounmap				__arm_iounmap
340 
341 /*
342  * io{read,write}{16,32}be() macros
343  */
344 #define ioread16be(p)		({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
345 #define ioread32be(p)		({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
346 
347 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
348 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
349 
350 #ifndef ioport_map
351 #define ioport_map ioport_map
352 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
353 #endif
354 #ifndef ioport_unmap
355 #define ioport_unmap ioport_unmap
356 extern void ioport_unmap(void __iomem *addr);
357 #endif
358 
359 struct pci_dev;
360 
361 #define pci_iounmap pci_iounmap
362 extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
363 
364 /*
365  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
366  * access
367  */
368 #define xlate_dev_mem_ptr(p)	__va(p)
369 
370 /*
371  * Convert a virtual cached pointer to an uncached pointer
372  */
373 #define xlate_dev_kmem_ptr(p)	p
374 
375 #include <asm-generic/io.h>
376 
377 /*
378  * can the hardware map this into one segment or not, given no other
379  * constraints.
380  */
381 #define BIOVEC_MERGEABLE(vec1, vec2)	\
382 	((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
383 
384 struct bio_vec;
385 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
386 				      const struct bio_vec *vec2);
387 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
388 	(__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&				\
389 	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
390 
391 #ifdef CONFIG_MMU
392 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
393 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
394 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
395 extern int devmem_is_allowed(unsigned long pfn);
396 #endif
397 
398 /*
399  * Register ISA memory and port locations for glibc iopl/inb/outb
400  * emulation.
401  */
402 extern void register_isa_ports(unsigned int mmio, unsigned int io,
403 			       unsigned int io_shift);
404 
405 #endif	/* __KERNEL__ */
406 #endif	/* __ASM_ARM_IO_H */
407