xref: /openbmc/linux/arch/arm/include/asm/io.h (revision 0c874100)
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/string.h>
27 #include <linux/types.h>
28 #include <asm/byteorder.h>
29 #include <asm/memory.h>
30 #include <asm-generic/pci_iomap.h>
31 
32 /*
33  * ISA I/O bus memory addresses are 1:1 with the physical address.
34  */
35 #define isa_virt_to_bus virt_to_phys
36 #define isa_page_to_bus page_to_phys
37 #define isa_bus_to_virt phys_to_virt
38 
39 /*
40  * Atomic MMIO-wide IO modify
41  */
42 extern void atomic_io_modify(void __iomem *reg, u32 mask, u32 set);
43 extern void atomic_io_modify_relaxed(void __iomem *reg, u32 mask, u32 set);
44 
45 /*
46  * Generic IO read/write.  These perform native-endian accesses.  Note
47  * that some architectures will want to re-define __raw_{read,write}w.
48  */
49 void __raw_writesb(volatile void __iomem *addr, const void *data, int bytelen);
50 void __raw_writesw(volatile void __iomem *addr, const void *data, int wordlen);
51 void __raw_writesl(volatile void __iomem *addr, const void *data, int longlen);
52 
53 void __raw_readsb(const volatile void __iomem *addr, void *data, int bytelen);
54 void __raw_readsw(const volatile void __iomem *addr, void *data, int wordlen);
55 void __raw_readsl(const volatile void __iomem *addr, void *data, int longlen);
56 
57 #if __LINUX_ARM_ARCH__ < 6
58 /*
59  * Half-word accesses are problematic with RiscPC due to limitations of
60  * the bus. Rather than special-case the machine, just let the compiler
61  * generate the access for CPUs prior to ARMv6.
62  */
63 #define __raw_readw(a)         (__chk_io_ptr(a), *(volatile unsigned short __force *)(a))
64 #define __raw_writew(v,a)      ((void)(__chk_io_ptr(a), *(volatile unsigned short __force *)(a) = (v)))
65 #else
66 /*
67  * When running under a hypervisor, we want to avoid I/O accesses with
68  * writeback addressing modes as these incur a significant performance
69  * overhead (the address generation must be emulated in software).
70  */
71 #define __raw_writew __raw_writew
72 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
73 {
74 	asm volatile("strh %1, %0"
75 		     : : "Q" (*(volatile u16 __force *)addr), "r" (val));
76 }
77 
78 #define __raw_readw __raw_readw
79 static inline u16 __raw_readw(const volatile void __iomem *addr)
80 {
81 	u16 val;
82 	asm volatile("ldrh %0, %1"
83 		     : "=r" (val)
84 		     : "Q" (*(volatile u16 __force *)addr));
85 	return val;
86 }
87 #endif
88 
89 #define __raw_writeb __raw_writeb
90 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
91 {
92 	asm volatile("strb %1, %0"
93 		     : : "Qo" (*(volatile u8 __force *)addr), "r" (val));
94 }
95 
96 #define __raw_writel __raw_writel
97 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
98 {
99 	asm volatile("str %1, %0"
100 		     : : "Qo" (*(volatile u32 __force *)addr), "r" (val));
101 }
102 
103 #define __raw_readb __raw_readb
104 static inline u8 __raw_readb(const volatile void __iomem *addr)
105 {
106 	u8 val;
107 	asm volatile("ldrb %0, %1"
108 		     : "=r" (val)
109 		     : "Qo" (*(volatile u8 __force *)addr));
110 	return val;
111 }
112 
113 #define __raw_readl __raw_readl
114 static inline u32 __raw_readl(const volatile void __iomem *addr)
115 {
116 	u32 val;
117 	asm volatile("ldr %0, %1"
118 		     : "=r" (val)
119 		     : "Qo" (*(volatile u32 __force *)addr));
120 	return val;
121 }
122 
123 /*
124  * Architecture ioremap implementation.
125  */
126 #define MT_DEVICE		0
127 #define MT_DEVICE_NONSHARED	1
128 #define MT_DEVICE_CACHED	2
129 #define MT_DEVICE_WC		3
130 /*
131  * types 4 onwards can be found in asm/mach/map.h and are undefined
132  * for ioremap
133  */
134 
135 /*
136  * __arm_ioremap takes CPU physical address.
137  * __arm_ioremap_pfn takes a Page Frame Number and an offset into that page
138  * The _caller variety takes a __builtin_return_address(0) value for
139  * /proc/vmalloc to use - and should only be used in non-inline functions.
140  */
141 extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
142 	void *);
143 extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
144 extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
145 extern void __iounmap(volatile void __iomem *addr);
146 
147 extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
148 	unsigned int, void *);
149 extern void (*arch_iounmap)(volatile void __iomem *);
150 
151 /*
152  * Bad read/write accesses...
153  */
154 extern void __readwrite_bug(const char *fn);
155 
156 /*
157  * A typesafe __io() helper
158  */
159 static inline void __iomem *__typesafe_io(unsigned long addr)
160 {
161 	return (void __iomem *)addr;
162 }
163 
164 #define IOMEM(x)	((void __force __iomem *)(x))
165 
166 /* IO barriers */
167 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
168 #include <asm/barrier.h>
169 #define __iormb()		rmb()
170 #define __iowmb()		wmb()
171 #else
172 #define __iormb()		do { } while (0)
173 #define __iowmb()		do { } while (0)
174 #endif
175 
176 /* PCI fixed i/o mapping */
177 #define PCI_IO_VIRT_BASE	0xfee00000
178 #define PCI_IOBASE		((void __iomem *)PCI_IO_VIRT_BASE)
179 
180 #if defined(CONFIG_PCI)
181 void pci_ioremap_set_mem_type(int mem_type);
182 #else
183 static inline void pci_ioremap_set_mem_type(int mem_type) {}
184 #endif
185 
186 extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
187 
188 /*
189  * PCI configuration space mapping function.
190  *
191  * The PCI specification does not allow configuration write
192  * transactions to be posted. Add an arch specific
193  * pci_remap_cfgspace() definition that is implemented
194  * through strongly ordered memory mappings.
195  */
196 #define pci_remap_cfgspace pci_remap_cfgspace
197 void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size);
198 /*
199  * Now, pick up the machine-defined IO definitions
200  */
201 #ifdef CONFIG_NEED_MACH_IO_H
202 #include <mach/io.h>
203 #elif defined(CONFIG_PCI)
204 #define IO_SPACE_LIMIT	((resource_size_t)0xfffff)
205 #define __io(a)		__typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
206 #else
207 #define __io(a)		__typesafe_io((a) & IO_SPACE_LIMIT)
208 #endif
209 
210 /*
211  * This is the limit of PC card/PCI/ISA IO space, which is by default
212  * 64K if we have PC card, PCI or ISA support.  Otherwise, default to
213  * zero to prevent ISA/PCI drivers claiming IO space (and potentially
214  * oopsing.)
215  *
216  * Only set this larger if you really need inb() et.al. to operate over
217  * a larger address space.  Note that SOC_COMMON ioremaps each sockets
218  * IO space area, and so inb() et.al. must be defined to operate as per
219  * readb() et.al. on such platforms.
220  */
221 #ifndef IO_SPACE_LIMIT
222 #if defined(CONFIG_PCMCIA_SOC_COMMON) || defined(CONFIG_PCMCIA_SOC_COMMON_MODULE)
223 #define IO_SPACE_LIMIT ((resource_size_t)0xffffffff)
224 #elif defined(CONFIG_PCI) || defined(CONFIG_ISA) || defined(CONFIG_PCCARD)
225 #define IO_SPACE_LIMIT ((resource_size_t)0xffff)
226 #else
227 #define IO_SPACE_LIMIT ((resource_size_t)0)
228 #endif
229 #endif
230 
231 /*
232  *  IO port access primitives
233  *  -------------------------
234  *
235  * The ARM doesn't have special IO access instructions; all IO is memory
236  * mapped.  Note that these are defined to perform little endian accesses
237  * only.  Their primary purpose is to access PCI and ISA peripherals.
238  *
239  * Note that for a big endian machine, this implies that the following
240  * big endian mode connectivity is in place, as described by numerous
241  * ARM documents:
242  *
243  *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
244  *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
245  *
246  * The machine specific io.h include defines __io to translate an "IO"
247  * address to a memory address.
248  *
249  * Note that we prevent GCC re-ordering or caching values in expressions
250  * by introducing sequence points into the in*() definitions.  Note that
251  * __raw_* do not guarantee this behaviour.
252  *
253  * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
254  */
255 #ifdef __io
256 #define outb(v,p)	({ __iowmb(); __raw_writeb(v,__io(p)); })
257 #define outw(v,p)	({ __iowmb(); __raw_writew((__force __u16) \
258 					cpu_to_le16(v),__io(p)); })
259 #define outl(v,p)	({ __iowmb(); __raw_writel((__force __u32) \
260 					cpu_to_le32(v),__io(p)); })
261 
262 #define inb(p)	({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
263 #define inw(p)	({ __u16 __v = le16_to_cpu((__force __le16) \
264 			__raw_readw(__io(p))); __iormb(); __v; })
265 #define inl(p)	({ __u32 __v = le32_to_cpu((__force __le32) \
266 			__raw_readl(__io(p))); __iormb(); __v; })
267 
268 #define outsb(p,d,l)		__raw_writesb(__io(p),d,l)
269 #define outsw(p,d,l)		__raw_writesw(__io(p),d,l)
270 #define outsl(p,d,l)		__raw_writesl(__io(p),d,l)
271 
272 #define insb(p,d,l)		__raw_readsb(__io(p),d,l)
273 #define insw(p,d,l)		__raw_readsw(__io(p),d,l)
274 #define insl(p,d,l)		__raw_readsl(__io(p),d,l)
275 #endif
276 
277 /*
278  * String version of IO memory access ops:
279  */
280 extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
281 extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
282 extern void _memset_io(volatile void __iomem *, int, size_t);
283 
284 #define mmiowb()
285 
286 /*
287  *  Memory access primitives
288  *  ------------------------
289  *
290  * These perform PCI memory accesses via an ioremap region.  They don't
291  * take an address as such, but a cookie.
292  *
293  * Again, these are defined to perform little endian accesses.  See the
294  * IO port primitives for more information.
295  */
296 #ifndef readl
297 #define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
298 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
299 					__raw_readw(c)); __r; })
300 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
301 					__raw_readl(c)); __r; })
302 
303 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
304 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
305 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
306 
307 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
308 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
309 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
310 
311 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
312 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
313 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
314 
315 #define readsb(p,d,l)		__raw_readsb(p,d,l)
316 #define readsw(p,d,l)		__raw_readsw(p,d,l)
317 #define readsl(p,d,l)		__raw_readsl(p,d,l)
318 
319 #define writesb(p,d,l)		__raw_writesb(p,d,l)
320 #define writesw(p,d,l)		__raw_writesw(p,d,l)
321 #define writesl(p,d,l)		__raw_writesl(p,d,l)
322 
323 #ifndef __ARMBE__
324 static inline void memset_io(volatile void __iomem *dst, unsigned c,
325 	size_t count)
326 {
327 	extern void mmioset(void *, unsigned int, size_t);
328 	mmioset((void __force *)dst, c, count);
329 }
330 #define memset_io(dst,c,count) memset_io(dst,c,count)
331 
332 static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
333 	size_t count)
334 {
335 	extern void mmiocpy(void *, const void *, size_t);
336 	mmiocpy(to, (const void __force *)from, count);
337 }
338 #define memcpy_fromio(to,from,count) memcpy_fromio(to,from,count)
339 
340 static inline void memcpy_toio(volatile void __iomem *to, const void *from,
341 	size_t count)
342 {
343 	extern void mmiocpy(void *, const void *, size_t);
344 	mmiocpy((void __force *)to, from, count);
345 }
346 #define memcpy_toio(to,from,count) memcpy_toio(to,from,count)
347 
348 #else
349 #define memset_io(c,v,l)	_memset_io(c,(v),(l))
350 #define memcpy_fromio(a,c,l)	_memcpy_fromio((a),c,(l))
351 #define memcpy_toio(c,a,l)	_memcpy_toio(c,(a),(l))
352 #endif
353 
354 #endif	/* readl */
355 
356 /*
357  * ioremap() and friends.
358  *
359  * ioremap() takes a resource address, and size.  Due to the ARM memory
360  * types, it is important to use the correct ioremap() function as each
361  * mapping has specific properties.
362  *
363  * Function		Memory type	Cacheability	Cache hint
364  * ioremap()		Device		n/a		n/a
365  * ioremap_nocache()	Device		n/a		n/a
366  * ioremap_cache()	Normal		Writeback	Read allocate
367  * ioremap_wc()		Normal		Non-cacheable	n/a
368  * ioremap_wt()		Normal		Non-cacheable	n/a
369  *
370  * All device mappings have the following properties:
371  * - no access speculation
372  * - no repetition (eg, on return from an exception)
373  * - number, order and size of accesses are maintained
374  * - unaligned accesses are "unpredictable"
375  * - writes may be delayed before they hit the endpoint device
376  *
377  * ioremap_nocache() is the same as ioremap() as there are too many device
378  * drivers using this for device registers, and documentation which tells
379  * people to use it for such for this to be any different.  This is not a
380  * safe fallback for memory-like mappings, or memory regions where the
381  * compiler may generate unaligned accesses - eg, via inlining its own
382  * memcpy.
383  *
384  * All normal memory mappings have the following properties:
385  * - reads can be repeated with no side effects
386  * - repeated reads return the last value written
387  * - reads can fetch additional locations without side effects
388  * - writes can be repeated (in certain cases) with no side effects
389  * - writes can be merged before accessing the target
390  * - unaligned accesses can be supported
391  * - ordering is not guaranteed without explicit dependencies or barrier
392  *   instructions
393  * - writes may be delayed before they hit the endpoint memory
394  *
395  * The cache hint is only a performance hint: CPUs may alias these hints.
396  * Eg, a CPU not implementing read allocate but implementing write allocate
397  * will provide a write allocate mapping instead.
398  */
399 void __iomem *ioremap(resource_size_t res_cookie, size_t size);
400 #define ioremap ioremap
401 #define ioremap_nocache ioremap
402 
403 /*
404  * Do not use ioremap_cache for mapping memory. Use memremap instead.
405  */
406 void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size);
407 #define ioremap_cache ioremap_cache
408 
409 /*
410  * Do not use ioremap_cached in new code. Provided for the benefit of
411  * the pxa2xx-flash MTD driver only.
412  */
413 void __iomem *ioremap_cached(resource_size_t res_cookie, size_t size);
414 
415 void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
416 #define ioremap_wc ioremap_wc
417 #define ioremap_wt ioremap_wc
418 
419 void iounmap(volatile void __iomem *iomem_cookie);
420 #define iounmap iounmap
421 
422 void *arch_memremap_wb(phys_addr_t phys_addr, size_t size);
423 #define arch_memremap_wb arch_memremap_wb
424 
425 /*
426  * io{read,write}{16,32}be() macros
427  */
428 #define ioread16be(p)		({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
429 #define ioread32be(p)		({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
430 
431 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
432 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
433 
434 #ifndef ioport_map
435 #define ioport_map ioport_map
436 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
437 #endif
438 #ifndef ioport_unmap
439 #define ioport_unmap ioport_unmap
440 extern void ioport_unmap(void __iomem *addr);
441 #endif
442 
443 struct pci_dev;
444 
445 #define pci_iounmap pci_iounmap
446 extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
447 
448 /*
449  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
450  * access
451  */
452 #define xlate_dev_mem_ptr(p)	__va(p)
453 
454 /*
455  * Convert a virtual cached pointer to an uncached pointer
456  */
457 #define xlate_dev_kmem_ptr(p)	p
458 
459 #include <asm-generic/io.h>
460 
461 #ifdef CONFIG_MMU
462 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
463 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
464 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
465 extern int devmem_is_allowed(unsigned long pfn);
466 #endif
467 
468 /*
469  * Register ISA memory and port locations for glibc iopl/inb/outb
470  * emulation.
471  */
472 extern void register_isa_ports(unsigned int mmio, unsigned int io,
473 			       unsigned int io_shift);
474 
475 #endif	/* __KERNEL__ */
476 #endif	/* __ASM_ARM_IO_H */
477