xref: /linux/arch/mips/include/asm/io.h (revision 37744feebc086908fd89760650f458ab19071750)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1994, 1995 Waldorf GmbH
7  * Copyright (C) 1994 - 2000, 06 Ralf Baechle
8  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9  * Copyright (C) 2004, 2005  MIPS Technologies, Inc.  All rights reserved.
10  *	Author: Maciej W. Rozycki <macro@mips.com>
11  */
12 #ifndef _ASM_IO_H
13 #define _ASM_IO_H
14 
15 #define ARCH_HAS_IOREMAP_WC
16 
17 #include <linux/compiler.h>
18 #include <linux/kernel.h>
19 #include <linux/types.h>
20 #include <linux/irqflags.h>
21 
22 #include <asm/addrspace.h>
23 #include <asm/barrier.h>
24 #include <asm/bug.h>
25 #include <asm/byteorder.h>
26 #include <asm/cpu.h>
27 #include <asm/cpu-features.h>
28 #include <asm-generic/iomap.h>
29 #include <asm/page.h>
30 #include <asm/pgtable-bits.h>
31 #include <asm/processor.h>
32 #include <asm/string.h>
33 
34 #include <ioremap.h>
35 #include <mangle-port.h>
36 
37 /*
38  * Raw operations are never swapped in software.  OTOH values that raw
39  * operations are working on may or may not have been swapped by the bus
40  * hardware.  An example use would be for flash memory that's used for
41  * execute in place.
42  */
43 # define __raw_ioswabb(a, x)	(x)
44 # define __raw_ioswabw(a, x)	(x)
45 # define __raw_ioswabl(a, x)	(x)
46 # define __raw_ioswabq(a, x)	(x)
47 # define ____raw_ioswabq(a, x)	(x)
48 
49 # define __relaxed_ioswabb ioswabb
50 # define __relaxed_ioswabw ioswabw
51 # define __relaxed_ioswabl ioswabl
52 # define __relaxed_ioswabq ioswabq
53 
54 /* ioswab[bwlq], __mem_ioswab[bwlq] are defined in mangle-port.h */
55 
56 #define IO_SPACE_LIMIT 0xffff
57 
58 /*
59  * On MIPS I/O ports are memory mapped, so we access them using normal
60  * load/store instructions. mips_io_port_base is the virtual address to
61  * which all ports are being mapped.  For sake of efficiency some code
62  * assumes that this is an address that can be loaded with a single lui
63  * instruction, so the lower 16 bits must be zero.  Should be true on
64  * on any sane architecture; generic code does not use this assumption.
65  */
66 extern unsigned long mips_io_port_base;
67 
68 static inline void set_io_port_base(unsigned long base)
69 {
70 	mips_io_port_base = base;
71 }
72 
73 /*
74  * Provide the necessary definitions for generic iomap. We make use of
75  * mips_io_port_base for iomap(), but we don't reserve any low addresses for
76  * use with I/O ports.
77  */
78 
79 #define HAVE_ARCH_PIO_SIZE
80 #define PIO_OFFSET	mips_io_port_base
81 #define PIO_MASK	IO_SPACE_LIMIT
82 #define PIO_RESERVED	0x0UL
83 
84 /*
85  * Enforce in-order execution of data I/O.  In the MIPS architecture
86  * these are equivalent to corresponding platform-specific memory
87  * barriers defined in <asm/barrier.h>.  API pinched from PowerPC,
88  * with sync additionally defined.
89  */
90 #define iobarrier_rw() mb()
91 #define iobarrier_r() rmb()
92 #define iobarrier_w() wmb()
93 #define iobarrier_sync() iob()
94 
95 /*
96  *     virt_to_phys    -       map virtual addresses to physical
97  *     @address: address to remap
98  *
99  *     The returned physical address is the physical (CPU) mapping for
100  *     the memory address given. It is only valid to use this function on
101  *     addresses directly mapped or allocated via kmalloc.
102  *
103  *     This function does not give bus mappings for DMA transfers. In
104  *     almost all conceivable cases a device driver should not be using
105  *     this function
106  */
107 static inline unsigned long virt_to_phys(volatile const void *address)
108 {
109 	return __pa(address);
110 }
111 
112 /*
113  *     phys_to_virt    -       map physical address to virtual
114  *     @address: address to remap
115  *
116  *     The returned virtual address is a current CPU mapping for
117  *     the memory address given. It is only valid to use this function on
118  *     addresses that have a kernel mapping
119  *
120  *     This function does not handle bus mappings for DMA transfers. In
121  *     almost all conceivable cases a device driver should not be using
122  *     this function
123  */
124 static inline void * phys_to_virt(unsigned long address)
125 {
126 	return (void *)(address + PAGE_OFFSET - PHYS_OFFSET);
127 }
128 
129 /*
130  * ISA I/O bus memory addresses are 1:1 with the physical address.
131  */
132 static inline unsigned long isa_virt_to_bus(volatile void *address)
133 {
134 	return virt_to_phys(address);
135 }
136 
137 static inline void *isa_bus_to_virt(unsigned long address)
138 {
139 	return phys_to_virt(address);
140 }
141 
142 /*
143  * However PCI ones are not necessarily 1:1 and therefore these interfaces
144  * are forbidden in portable PCI drivers.
145  *
146  * Allow them for x86 for legacy drivers, though.
147  */
148 #define virt_to_bus virt_to_phys
149 #define bus_to_virt phys_to_virt
150 
151 /*
152  * Change "struct page" to physical address.
153  */
154 #define page_to_phys(page)	((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
155 
156 extern void __iomem * __ioremap(phys_addr_t offset, phys_addr_t size, unsigned long flags);
157 extern void __iounmap(const volatile void __iomem *addr);
158 
159 static inline void __iomem * __ioremap_mode(phys_addr_t offset, unsigned long size,
160 	unsigned long flags)
161 {
162 	void __iomem *addr = plat_ioremap(offset, size, flags);
163 
164 	if (addr)
165 		return addr;
166 
167 #define __IS_LOW512(addr) (!((phys_addr_t)(addr) & (phys_addr_t) ~0x1fffffffULL))
168 
169 	if (cpu_has_64bit_addresses) {
170 		u64 base = UNCAC_BASE;
171 
172 		/*
173 		 * R10000 supports a 2 bit uncached attribute therefore
174 		 * UNCAC_BASE may not equal IO_BASE.
175 		 */
176 		if (flags == _CACHE_UNCACHED)
177 			base = (u64) IO_BASE;
178 		return (void __iomem *) (unsigned long) (base + offset);
179 	} else if (__builtin_constant_p(offset) &&
180 		   __builtin_constant_p(size) && __builtin_constant_p(flags)) {
181 		phys_addr_t phys_addr, last_addr;
182 
183 		phys_addr = fixup_bigphys_addr(offset, size);
184 
185 		/* Don't allow wraparound or zero size. */
186 		last_addr = phys_addr + size - 1;
187 		if (!size || last_addr < phys_addr)
188 			return NULL;
189 
190 		/*
191 		 * Map uncached objects in the low 512MB of address
192 		 * space using KSEG1.
193 		 */
194 		if (__IS_LOW512(phys_addr) && __IS_LOW512(last_addr) &&
195 		    flags == _CACHE_UNCACHED)
196 			return (void __iomem *)
197 				(unsigned long)CKSEG1ADDR(phys_addr);
198 	}
199 
200 	return __ioremap(offset, size, flags);
201 
202 #undef __IS_LOW512
203 }
204 
205 /*
206  * ioremap_prot     -   map bus memory into CPU space
207  * @offset:    bus address of the memory
208  * @size:      size of the resource to map
209 
210  * ioremap_prot gives the caller control over cache coherency attributes (CCA)
211  */
212 static inline void __iomem *ioremap_prot(phys_addr_t offset,
213 		unsigned long size, unsigned long prot_val) {
214 	return __ioremap_mode(offset, size, prot_val & _CACHE_MASK);
215 }
216 
217 /*
218  * ioremap     -   map bus memory into CPU space
219  * @offset:    bus address of the memory
220  * @size:      size of the resource to map
221  *
222  * ioremap performs a platform specific sequence of operations to
223  * make bus memory CPU accessible via the readb/readw/readl/writeb/
224  * writew/writel functions and the other mmio helpers. The returned
225  * address is not guaranteed to be usable directly as a virtual
226  * address.
227  */
228 #define ioremap(offset, size)						\
229 	__ioremap_mode((offset), (size), _CACHE_UNCACHED)
230 #define ioremap_uc		ioremap
231 
232 /*
233  * ioremap_cache -	map bus memory into CPU space
234  * @offset:	    bus address of the memory
235  * @size:	    size of the resource to map
236  *
237  * ioremap_cache performs a platform specific sequence of operations to
238  * make bus memory CPU accessible via the readb/readw/readl/writeb/
239  * writew/writel functions and the other mmio helpers. The returned
240  * address is not guaranteed to be usable directly as a virtual
241  * address.
242  *
243  * This version of ioremap ensures that the memory is marked cachable by
244  * the CPU.  Also enables full write-combining.	 Useful for some
245  * memory-like regions on I/O busses.
246  */
247 #define ioremap_cache(offset, size)					\
248 	__ioremap_mode((offset), (size), _page_cachable_default)
249 
250 /*
251  * ioremap_wc     -   map bus memory into CPU space
252  * @offset:    bus address of the memory
253  * @size:      size of the resource to map
254  *
255  * ioremap_wc performs a platform specific sequence of operations to
256  * make bus memory CPU accessible via the readb/readw/readl/writeb/
257  * writew/writel functions and the other mmio helpers. The returned
258  * address is not guaranteed to be usable directly as a virtual
259  * address.
260  *
261  * This version of ioremap ensures that the memory is marked uncachable
262  * but accelerated by means of write-combining feature. It is specifically
263  * useful for PCIe prefetchable windows, which may vastly improve a
264  * communications performance. If it was determined on boot stage, what
265  * CPU CCA doesn't support UCA, the method shall fall-back to the
266  * _CACHE_UNCACHED option (see cpu_probe() method).
267  */
268 #define ioremap_wc(offset, size)					\
269 	__ioremap_mode((offset), (size), boot_cpu_data.writecombine)
270 
271 static inline void iounmap(const volatile void __iomem *addr)
272 {
273 	if (plat_iounmap(addr))
274 		return;
275 
276 #define __IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == CKSEG1)
277 
278 	if (cpu_has_64bit_addresses ||
279 	    (__builtin_constant_p(addr) && __IS_KSEG1(addr)))
280 		return;
281 
282 	__iounmap(addr);
283 
284 #undef __IS_KSEG1
285 }
286 
287 #if defined(CONFIG_CPU_CAVIUM_OCTEON) || defined(CONFIG_CPU_LOONGSON64)
288 #define war_io_reorder_wmb()		wmb()
289 #else
290 #define war_io_reorder_wmb()		barrier()
291 #endif
292 
293 #define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, barrier, relax, irq)	\
294 									\
295 static inline void pfx##write##bwlq(type val,				\
296 				    volatile void __iomem *mem)		\
297 {									\
298 	volatile type *__mem;						\
299 	type __val;							\
300 									\
301 	if (barrier)							\
302 		iobarrier_rw();						\
303 	else								\
304 		war_io_reorder_wmb();					\
305 									\
306 	__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));	\
307 									\
308 	__val = pfx##ioswab##bwlq(__mem, val);				\
309 									\
310 	if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
311 		*__mem = __val;						\
312 	else if (cpu_has_64bits) {					\
313 		unsigned long __flags;					\
314 		type __tmp;						\
315 									\
316 		if (irq)						\
317 			local_irq_save(__flags);			\
318 		__asm__ __volatile__(					\
319 			".set	push"		"\t\t# __writeq""\n\t"	\
320 			".set	arch=r4000"			"\n\t"	\
321 			"dsll32 %L0, %L0, 0"			"\n\t"	\
322 			"dsrl32 %L0, %L0, 0"			"\n\t"	\
323 			"dsll32 %M0, %M0, 0"			"\n\t"	\
324 			"or	%L0, %L0, %M0"			"\n\t"	\
325 			"sd	%L0, %2"			"\n\t"	\
326 			".set	pop"				"\n"	\
327 			: "=r" (__tmp)					\
328 			: "0" (__val), "m" (*__mem));			\
329 		if (irq)						\
330 			local_irq_restore(__flags);			\
331 	} else								\
332 		BUG();							\
333 }									\
334 									\
335 static inline type pfx##read##bwlq(const volatile void __iomem *mem)	\
336 {									\
337 	volatile type *__mem;						\
338 	type __val;							\
339 									\
340 	__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));	\
341 									\
342 	if (barrier)							\
343 		iobarrier_rw();						\
344 									\
345 	if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
346 		__val = *__mem;						\
347 	else if (cpu_has_64bits) {					\
348 		unsigned long __flags;					\
349 									\
350 		if (irq)						\
351 			local_irq_save(__flags);			\
352 		__asm__ __volatile__(					\
353 			".set	push"		"\t\t# __readq" "\n\t"	\
354 			".set	arch=r4000"			"\n\t"	\
355 			"ld	%L0, %1"			"\n\t"	\
356 			"dsra32 %M0, %L0, 0"			"\n\t"	\
357 			"sll	%L0, %L0, 0"			"\n\t"	\
358 			".set	pop"				"\n"	\
359 			: "=r" (__val)					\
360 			: "m" (*__mem));				\
361 		if (irq)						\
362 			local_irq_restore(__flags);			\
363 	} else {							\
364 		__val = 0;						\
365 		BUG();							\
366 	}								\
367 									\
368 	/* prevent prefetching of coherent DMA data prematurely */	\
369 	if (!relax)							\
370 		rmb();							\
371 	return pfx##ioswab##bwlq(__mem, __val);				\
372 }
373 
374 #define __BUILD_IOPORT_SINGLE(pfx, bwlq, type, barrier, relax, p)	\
375 									\
376 static inline void pfx##out##bwlq##p(type val, unsigned long port)	\
377 {									\
378 	volatile type *__addr;						\
379 	type __val;							\
380 									\
381 	if (barrier)							\
382 		iobarrier_rw();						\
383 	else								\
384 		war_io_reorder_wmb();					\
385 									\
386 	__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
387 									\
388 	__val = pfx##ioswab##bwlq(__addr, val);				\
389 									\
390 	/* Really, we want this to be atomic */				\
391 	BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));		\
392 									\
393 	*__addr = __val;						\
394 }									\
395 									\
396 static inline type pfx##in##bwlq##p(unsigned long port)			\
397 {									\
398 	volatile type *__addr;						\
399 	type __val;							\
400 									\
401 	__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
402 									\
403 	BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));		\
404 									\
405 	if (barrier)							\
406 		iobarrier_rw();						\
407 									\
408 	__val = *__addr;						\
409 									\
410 	/* prevent prefetching of coherent DMA data prematurely */	\
411 	if (!relax)							\
412 		rmb();							\
413 	return pfx##ioswab##bwlq(__addr, __val);			\
414 }
415 
416 #define __BUILD_MEMORY_PFX(bus, bwlq, type, relax)			\
417 									\
418 __BUILD_MEMORY_SINGLE(bus, bwlq, type, 1, relax, 1)
419 
420 #define BUILDIO_MEM(bwlq, type)						\
421 									\
422 __BUILD_MEMORY_PFX(__raw_, bwlq, type, 0)				\
423 __BUILD_MEMORY_PFX(__relaxed_, bwlq, type, 1)				\
424 __BUILD_MEMORY_PFX(__mem_, bwlq, type, 0)				\
425 __BUILD_MEMORY_PFX(, bwlq, type, 0)
426 
427 BUILDIO_MEM(b, u8)
428 BUILDIO_MEM(w, u16)
429 BUILDIO_MEM(l, u32)
430 #ifdef CONFIG_64BIT
431 BUILDIO_MEM(q, u64)
432 #else
433 __BUILD_MEMORY_PFX(__raw_, q, u64, 0)
434 __BUILD_MEMORY_PFX(__mem_, q, u64, 0)
435 #endif
436 
437 #define __BUILD_IOPORT_PFX(bus, bwlq, type)				\
438 	__BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0,)			\
439 	__BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0, _p)
440 
441 #define BUILDIO_IOPORT(bwlq, type)					\
442 	__BUILD_IOPORT_PFX(, bwlq, type)				\
443 	__BUILD_IOPORT_PFX(__mem_, bwlq, type)
444 
445 BUILDIO_IOPORT(b, u8)
446 BUILDIO_IOPORT(w, u16)
447 BUILDIO_IOPORT(l, u32)
448 #ifdef CONFIG_64BIT
449 BUILDIO_IOPORT(q, u64)
450 #endif
451 
452 #define __BUILDIO(bwlq, type)						\
453 									\
454 __BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 1, 0, 0)
455 
456 __BUILDIO(q, u64)
457 
458 #define readb_relaxed			__relaxed_readb
459 #define readw_relaxed			__relaxed_readw
460 #define readl_relaxed			__relaxed_readl
461 #ifdef CONFIG_64BIT
462 #define readq_relaxed			__relaxed_readq
463 #endif
464 
465 #define writeb_relaxed			__relaxed_writeb
466 #define writew_relaxed			__relaxed_writew
467 #define writel_relaxed			__relaxed_writel
468 #ifdef CONFIG_64BIT
469 #define writeq_relaxed			__relaxed_writeq
470 #endif
471 
472 #define readb_be(addr)							\
473 	__raw_readb((__force unsigned *)(addr))
474 #define readw_be(addr)							\
475 	be16_to_cpu(__raw_readw((__force unsigned *)(addr)))
476 #define readl_be(addr)							\
477 	be32_to_cpu(__raw_readl((__force unsigned *)(addr)))
478 #define readq_be(addr)							\
479 	be64_to_cpu(__raw_readq((__force unsigned *)(addr)))
480 
481 #define writeb_be(val, addr)						\
482 	__raw_writeb((val), (__force unsigned *)(addr))
483 #define writew_be(val, addr)						\
484 	__raw_writew(cpu_to_be16((val)), (__force unsigned *)(addr))
485 #define writel_be(val, addr)						\
486 	__raw_writel(cpu_to_be32((val)), (__force unsigned *)(addr))
487 #define writeq_be(val, addr)						\
488 	__raw_writeq(cpu_to_be64((val)), (__force unsigned *)(addr))
489 
490 /*
491  * Some code tests for these symbols
492  */
493 #ifdef CONFIG_64BIT
494 #define readq				readq
495 #define writeq				writeq
496 #endif
497 
498 #define __BUILD_MEMORY_STRING(bwlq, type)				\
499 									\
500 static inline void writes##bwlq(volatile void __iomem *mem,		\
501 				const void *addr, unsigned int count)	\
502 {									\
503 	const volatile type *__addr = addr;				\
504 									\
505 	while (count--) {						\
506 		__mem_write##bwlq(*__addr, mem);			\
507 		__addr++;						\
508 	}								\
509 }									\
510 									\
511 static inline void reads##bwlq(volatile void __iomem *mem, void *addr,	\
512 			       unsigned int count)			\
513 {									\
514 	volatile type *__addr = addr;					\
515 									\
516 	while (count--) {						\
517 		*__addr = __mem_read##bwlq(mem);			\
518 		__addr++;						\
519 	}								\
520 }
521 
522 #define __BUILD_IOPORT_STRING(bwlq, type)				\
523 									\
524 static inline void outs##bwlq(unsigned long port, const void *addr,	\
525 			      unsigned int count)			\
526 {									\
527 	const volatile type *__addr = addr;				\
528 									\
529 	while (count--) {						\
530 		__mem_out##bwlq(*__addr, port);				\
531 		__addr++;						\
532 	}								\
533 }									\
534 									\
535 static inline void ins##bwlq(unsigned long port, void *addr,		\
536 			     unsigned int count)			\
537 {									\
538 	volatile type *__addr = addr;					\
539 									\
540 	while (count--) {						\
541 		*__addr = __mem_in##bwlq(port);				\
542 		__addr++;						\
543 	}								\
544 }
545 
546 #define BUILDSTRING(bwlq, type)						\
547 									\
548 __BUILD_MEMORY_STRING(bwlq, type)					\
549 __BUILD_IOPORT_STRING(bwlq, type)
550 
551 BUILDSTRING(b, u8)
552 BUILDSTRING(w, u16)
553 BUILDSTRING(l, u32)
554 #ifdef CONFIG_64BIT
555 BUILDSTRING(q, u64)
556 #endif
557 
558 static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
559 {
560 	memset((void __force *) addr, val, count);
561 }
562 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
563 {
564 	memcpy(dst, (void __force *) src, count);
565 }
566 static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count)
567 {
568 	memcpy((void __force *) dst, src, count);
569 }
570 
571 /*
572  * The caches on some architectures aren't dma-coherent and have need to
573  * handle this in software.  There are three types of operations that
574  * can be applied to dma buffers.
575  *
576  *  - dma_cache_wback_inv(start, size) makes caches and coherent by
577  *    writing the content of the caches back to memory, if necessary.
578  *    The function also invalidates the affected part of the caches as
579  *    necessary before DMA transfers from outside to memory.
580  *  - dma_cache_wback(start, size) makes caches and coherent by
581  *    writing the content of the caches back to memory, if necessary.
582  *    The function also invalidates the affected part of the caches as
583  *    necessary before DMA transfers from outside to memory.
584  *  - dma_cache_inv(start, size) invalidates the affected parts of the
585  *    caches.  Dirty lines of the caches may be written back or simply
586  *    be discarded.  This operation is necessary before dma operations
587  *    to the memory.
588  *
589  * This API used to be exported; it now is for arch code internal use only.
590  */
591 #ifdef CONFIG_DMA_NONCOHERENT
592 
593 extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
594 extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
595 extern void (*_dma_cache_inv)(unsigned long start, unsigned long size);
596 
597 #define dma_cache_wback_inv(start, size)	_dma_cache_wback_inv(start, size)
598 #define dma_cache_wback(start, size)		_dma_cache_wback(start, size)
599 #define dma_cache_inv(start, size)		_dma_cache_inv(start, size)
600 
601 #else /* Sane hardware */
602 
603 #define dma_cache_wback_inv(start,size) \
604 	do { (void) (start); (void) (size); } while (0)
605 #define dma_cache_wback(start,size)	\
606 	do { (void) (start); (void) (size); } while (0)
607 #define dma_cache_inv(start,size)	\
608 	do { (void) (start); (void) (size); } while (0)
609 
610 #endif /* CONFIG_DMA_NONCOHERENT */
611 
612 /*
613  * Read a 32-bit register that requires a 64-bit read cycle on the bus.
614  * Avoid interrupt mucking, just adjust the address for 4-byte access.
615  * Assume the addresses are 8-byte aligned.
616  */
617 #ifdef __MIPSEB__
618 #define __CSR_32_ADJUST 4
619 #else
620 #define __CSR_32_ADJUST 0
621 #endif
622 
623 #define csr_out32(v, a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST) = (v))
624 #define csr_in32(a)    (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST))
625 
626 /*
627  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
628  * access
629  */
630 #define xlate_dev_mem_ptr(p)	__va(p)
631 
632 /*
633  * Convert a virtual cached pointer to an uncached pointer
634  */
635 #define xlate_dev_kmem_ptr(p)	p
636 
637 void __ioread64_copy(void *to, const void __iomem *from, size_t count);
638 
639 #endif /* _ASM_IO_H */
640