xref: /linux/arch/mips/include/asm/io.h (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
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 #include <mangle-port.h>
34 
35 /*
36  * Raw operations are never swapped in software.  OTOH values that raw
37  * operations are working on may or may not have been swapped by the bus
38  * hardware.  An example use would be for flash memory that's used for
39  * execute in place.
40  */
41 # define __raw_ioswabb(a, x)	(x)
42 # define __raw_ioswabw(a, x)	(x)
43 # define __raw_ioswabl(a, x)	(x)
44 # define __raw_ioswabq(a, x)	(x)
45 # define ____raw_ioswabq(a, x)	(x)
46 
47 # define __relaxed_ioswabb ioswabb
48 # define __relaxed_ioswabw ioswabw
49 # define __relaxed_ioswabl ioswabl
50 # define __relaxed_ioswabq ioswabq
51 
52 /* ioswab[bwlq], __mem_ioswab[bwlq] are defined in mangle-port.h */
53 
54 /*
55  * On MIPS I/O ports are memory mapped, so we access them using normal
56  * load/store instructions. mips_io_port_base is the virtual address to
57  * which all ports are being mapped.  For sake of efficiency some code
58  * assumes that this is an address that can be loaded with a single lui
59  * instruction, so the lower 16 bits must be zero.  Should be true on
60  * any sane architecture; generic code does not use this assumption.
61  */
62 extern unsigned long mips_io_port_base;
63 
64 static inline void set_io_port_base(unsigned long base)
65 {
66 	mips_io_port_base = base;
67 }
68 
69 /*
70  * Provide the necessary definitions for generic iomap. We make use of
71  * mips_io_port_base for iomap(), but we don't reserve any low addresses for
72  * use with I/O ports.
73  */
74 
75 #define HAVE_ARCH_PIO_SIZE
76 #define PIO_OFFSET	mips_io_port_base
77 #define PIO_MASK	IO_SPACE_LIMIT
78 #define PIO_RESERVED	0x0UL
79 
80 /*
81  * Enforce in-order execution of data I/O.  In the MIPS architecture
82  * these are equivalent to corresponding platform-specific memory
83  * barriers defined in <asm/barrier.h>.  API pinched from PowerPC,
84  * with sync additionally defined.
85  */
86 #define iobarrier_rw() mb()
87 #define iobarrier_r() rmb()
88 #define iobarrier_w() wmb()
89 #define iobarrier_sync() iob()
90 
91 /*
92  *     virt_to_phys    -       map virtual addresses to physical
93  *     @address: address to remap
94  *
95  *     The returned physical address is the physical (CPU) mapping for
96  *     the memory address given. It is only valid to use this function on
97  *     addresses directly mapped or allocated via kmalloc.
98  *
99  *     This function does not give bus mappings for DMA transfers. In
100  *     almost all conceivable cases a device driver should not be using
101  *     this function
102  */
103 static inline unsigned long virt_to_phys(volatile const void *address)
104 {
105 	return __pa(address);
106 }
107 
108 /*
109  *     phys_to_virt    -       map physical address to virtual
110  *     @address: address to remap
111  *
112  *     The returned virtual address is a current CPU mapping for
113  *     the memory address given. It is only valid to use this function on
114  *     addresses that have a kernel mapping
115  *
116  *     This function does not handle bus mappings for DMA transfers. In
117  *     almost all conceivable cases a device driver should not be using
118  *     this function
119  */
120 static inline void * phys_to_virt(unsigned long address)
121 {
122 	return (void *)(address + PAGE_OFFSET - PHYS_OFFSET);
123 }
124 
125 /*
126  * ISA I/O bus memory addresses are 1:1 with the physical address.
127  */
128 static inline unsigned long isa_virt_to_bus(volatile void *address)
129 {
130 	return virt_to_phys(address);
131 }
132 
133 static inline void *isa_bus_to_virt(unsigned long address)
134 {
135 	return phys_to_virt(address);
136 }
137 
138 /*
139  * However PCI ones are not necessarily 1:1 and therefore these interfaces
140  * are forbidden in portable PCI drivers.
141  *
142  * Allow them for x86 for legacy drivers, though.
143  */
144 #define virt_to_bus virt_to_phys
145 #define bus_to_virt phys_to_virt
146 
147 /*
148  * Change "struct page" to physical address.
149  */
150 #define page_to_phys(page)	((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
151 
152 void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
153 		unsigned long prot_val);
154 void iounmap(const volatile void __iomem *addr);
155 
156 /*
157  * ioremap     -   map bus memory into CPU space
158  * @offset:    bus address of the memory
159  * @size:      size of the resource to map
160  *
161  * ioremap performs a platform specific sequence of operations to
162  * make bus memory CPU accessible via the readb/readw/readl/writeb/
163  * writew/writel functions and the other mmio helpers. The returned
164  * address is not guaranteed to be usable directly as a virtual
165  * address.
166  */
167 #define ioremap(offset, size)						\
168 	ioremap_prot((offset), (size), _CACHE_UNCACHED)
169 #define ioremap_uc		ioremap
170 
171 /*
172  * ioremap_cache -	map bus memory into CPU space
173  * @offset:	    bus address of the memory
174  * @size:	    size of the resource to map
175  *
176  * ioremap_cache performs a platform specific sequence of operations to
177  * make bus memory CPU accessible via the readb/readw/readl/writeb/
178  * writew/writel functions and the other mmio helpers. The returned
179  * address is not guaranteed to be usable directly as a virtual
180  * address.
181  *
182  * This version of ioremap ensures that the memory is marked cachable by
183  * the CPU.  Also enables full write-combining.	 Useful for some
184  * memory-like regions on I/O busses.
185  */
186 #define ioremap_cache(offset, size)					\
187 	ioremap_prot((offset), (size), _page_cachable_default)
188 
189 /*
190  * ioremap_wc     -   map bus memory into CPU space
191  * @offset:    bus address of the memory
192  * @size:      size of the resource to map
193  *
194  * ioremap_wc performs a platform specific sequence of operations to
195  * make bus memory CPU accessible via the readb/readw/readl/writeb/
196  * writew/writel functions and the other mmio helpers. The returned
197  * address is not guaranteed to be usable directly as a virtual
198  * address.
199  *
200  * This version of ioremap ensures that the memory is marked uncachable
201  * but accelerated by means of write-combining feature. It is specifically
202  * useful for PCIe prefetchable windows, which may vastly improve a
203  * communications performance. If it was determined on boot stage, what
204  * CPU CCA doesn't support UCA, the method shall fall-back to the
205  * _CACHE_UNCACHED option (see cpu_probe() method).
206  */
207 #define ioremap_wc(offset, size)					\
208 	ioremap_prot((offset), (size), boot_cpu_data.writecombine)
209 
210 #if defined(CONFIG_CPU_CAVIUM_OCTEON) || defined(CONFIG_CPU_LOONGSON64)
211 #define war_io_reorder_wmb()		wmb()
212 #else
213 #define war_io_reorder_wmb()		barrier()
214 #endif
215 
216 #define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, barrier, relax, irq)	\
217 									\
218 static inline void pfx##write##bwlq(type val,				\
219 				    volatile void __iomem *mem)		\
220 {									\
221 	volatile type *__mem;						\
222 	type __val;							\
223 									\
224 	if (barrier)							\
225 		iobarrier_rw();						\
226 	else								\
227 		war_io_reorder_wmb();					\
228 									\
229 	__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));	\
230 									\
231 	__val = pfx##ioswab##bwlq(__mem, val);				\
232 									\
233 	if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
234 		*__mem = __val;						\
235 	else if (cpu_has_64bits) {					\
236 		unsigned long __flags;					\
237 		type __tmp;						\
238 									\
239 		if (irq)						\
240 			local_irq_save(__flags);			\
241 		__asm__ __volatile__(					\
242 			".set	push"		"\t\t# __writeq""\n\t"	\
243 			".set	arch=r4000"			"\n\t"	\
244 			"dsll32 %L0, %L0, 0"			"\n\t"	\
245 			"dsrl32 %L0, %L0, 0"			"\n\t"	\
246 			"dsll32 %M0, %M0, 0"			"\n\t"	\
247 			"or	%L0, %L0, %M0"			"\n\t"	\
248 			"sd	%L0, %2"			"\n\t"	\
249 			".set	pop"				"\n"	\
250 			: "=r" (__tmp)					\
251 			: "0" (__val), "m" (*__mem));			\
252 		if (irq)						\
253 			local_irq_restore(__flags);			\
254 	} else								\
255 		BUG();							\
256 }									\
257 									\
258 static inline type pfx##read##bwlq(const volatile void __iomem *mem)	\
259 {									\
260 	volatile type *__mem;						\
261 	type __val;							\
262 									\
263 	__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));	\
264 									\
265 	if (barrier)							\
266 		iobarrier_rw();						\
267 									\
268 	if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
269 		__val = *__mem;						\
270 	else if (cpu_has_64bits) {					\
271 		unsigned long __flags;					\
272 									\
273 		if (irq)						\
274 			local_irq_save(__flags);			\
275 		__asm__ __volatile__(					\
276 			".set	push"		"\t\t# __readq" "\n\t"	\
277 			".set	arch=r4000"			"\n\t"	\
278 			"ld	%L0, %1"			"\n\t"	\
279 			"dsra32 %M0, %L0, 0"			"\n\t"	\
280 			"sll	%L0, %L0, 0"			"\n\t"	\
281 			".set	pop"				"\n"	\
282 			: "=r" (__val)					\
283 			: "m" (*__mem));				\
284 		if (irq)						\
285 			local_irq_restore(__flags);			\
286 	} else {							\
287 		__val = 0;						\
288 		BUG();							\
289 	}								\
290 									\
291 	/* prevent prefetching of coherent DMA data prematurely */	\
292 	if (!relax)							\
293 		rmb();							\
294 	return pfx##ioswab##bwlq(__mem, __val);				\
295 }
296 
297 #define __BUILD_IOPORT_SINGLE(pfx, bwlq, type, barrier, relax, p)	\
298 									\
299 static inline void pfx##out##bwlq##p(type val, unsigned long port)	\
300 {									\
301 	volatile type *__addr;						\
302 	type __val;							\
303 									\
304 	if (barrier)							\
305 		iobarrier_rw();						\
306 	else								\
307 		war_io_reorder_wmb();					\
308 									\
309 	__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
310 									\
311 	__val = pfx##ioswab##bwlq(__addr, val);				\
312 									\
313 	/* Really, we want this to be atomic */				\
314 	BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));		\
315 									\
316 	*__addr = __val;						\
317 }									\
318 									\
319 static inline type pfx##in##bwlq##p(unsigned long port)			\
320 {									\
321 	volatile type *__addr;						\
322 	type __val;							\
323 									\
324 	__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
325 									\
326 	BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));		\
327 									\
328 	if (barrier)							\
329 		iobarrier_rw();						\
330 									\
331 	__val = *__addr;						\
332 									\
333 	/* prevent prefetching of coherent DMA data prematurely */	\
334 	if (!relax)							\
335 		rmb();							\
336 	return pfx##ioswab##bwlq(__addr, __val);			\
337 }
338 
339 #define __BUILD_MEMORY_PFX(bus, bwlq, type, relax)			\
340 									\
341 __BUILD_MEMORY_SINGLE(bus, bwlq, type, 1, relax, 1)
342 
343 #define BUILDIO_MEM(bwlq, type)						\
344 									\
345 __BUILD_MEMORY_PFX(__raw_, bwlq, type, 0)				\
346 __BUILD_MEMORY_PFX(__relaxed_, bwlq, type, 1)				\
347 __BUILD_MEMORY_PFX(__mem_, bwlq, type, 0)				\
348 __BUILD_MEMORY_PFX(, bwlq, type, 0)
349 
350 BUILDIO_MEM(b, u8)
351 BUILDIO_MEM(w, u16)
352 BUILDIO_MEM(l, u32)
353 #ifdef CONFIG_64BIT
354 BUILDIO_MEM(q, u64)
355 #else
356 __BUILD_MEMORY_PFX(__raw_, q, u64, 0)
357 __BUILD_MEMORY_PFX(__mem_, q, u64, 0)
358 #endif
359 
360 #define __BUILD_IOPORT_PFX(bus, bwlq, type)				\
361 	__BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0,)			\
362 	__BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0, _p)
363 
364 #define BUILDIO_IOPORT(bwlq, type)					\
365 	__BUILD_IOPORT_PFX(, bwlq, type)				\
366 	__BUILD_IOPORT_PFX(__mem_, bwlq, type)
367 
368 BUILDIO_IOPORT(b, u8)
369 BUILDIO_IOPORT(w, u16)
370 BUILDIO_IOPORT(l, u32)
371 #ifdef CONFIG_64BIT
372 BUILDIO_IOPORT(q, u64)
373 #endif
374 
375 #define __BUILDIO(bwlq, type)						\
376 									\
377 __BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 1, 0, 0)
378 
379 __BUILDIO(q, u64)
380 
381 #define readb_relaxed			__relaxed_readb
382 #define readw_relaxed			__relaxed_readw
383 #define readl_relaxed			__relaxed_readl
384 #ifdef CONFIG_64BIT
385 #define readq_relaxed			__relaxed_readq
386 #endif
387 
388 #define writeb_relaxed			__relaxed_writeb
389 #define writew_relaxed			__relaxed_writew
390 #define writel_relaxed			__relaxed_writel
391 #ifdef CONFIG_64BIT
392 #define writeq_relaxed			__relaxed_writeq
393 #endif
394 
395 #define readb_be(addr)							\
396 	__raw_readb((__force unsigned *)(addr))
397 #define readw_be(addr)							\
398 	be16_to_cpu(__raw_readw((__force unsigned *)(addr)))
399 #define readl_be(addr)							\
400 	be32_to_cpu(__raw_readl((__force unsigned *)(addr)))
401 #define readq_be(addr)							\
402 	be64_to_cpu(__raw_readq((__force unsigned *)(addr)))
403 
404 #define writeb_be(val, addr)						\
405 	__raw_writeb((val), (__force unsigned *)(addr))
406 #define writew_be(val, addr)						\
407 	__raw_writew(cpu_to_be16((val)), (__force unsigned *)(addr))
408 #define writel_be(val, addr)						\
409 	__raw_writel(cpu_to_be32((val)), (__force unsigned *)(addr))
410 #define writeq_be(val, addr)						\
411 	__raw_writeq(cpu_to_be64((val)), (__force unsigned *)(addr))
412 
413 /*
414  * Some code tests for these symbols
415  */
416 #ifdef CONFIG_64BIT
417 #define readq				readq
418 #define writeq				writeq
419 #endif
420 
421 #define __BUILD_MEMORY_STRING(bwlq, type)				\
422 									\
423 static inline void writes##bwlq(volatile void __iomem *mem,		\
424 				const void *addr, unsigned int count)	\
425 {									\
426 	const volatile type *__addr = addr;				\
427 									\
428 	while (count--) {						\
429 		__mem_write##bwlq(*__addr, mem);			\
430 		__addr++;						\
431 	}								\
432 }									\
433 									\
434 static inline void reads##bwlq(volatile void __iomem *mem, void *addr,	\
435 			       unsigned int count)			\
436 {									\
437 	volatile type *__addr = addr;					\
438 									\
439 	while (count--) {						\
440 		*__addr = __mem_read##bwlq(mem);			\
441 		__addr++;						\
442 	}								\
443 }
444 
445 #define __BUILD_IOPORT_STRING(bwlq, type)				\
446 									\
447 static inline void outs##bwlq(unsigned long port, const void *addr,	\
448 			      unsigned int count)			\
449 {									\
450 	const volatile type *__addr = addr;				\
451 									\
452 	while (count--) {						\
453 		__mem_out##bwlq(*__addr, port);				\
454 		__addr++;						\
455 	}								\
456 }									\
457 									\
458 static inline void ins##bwlq(unsigned long port, void *addr,		\
459 			     unsigned int count)			\
460 {									\
461 	volatile type *__addr = addr;					\
462 									\
463 	while (count--) {						\
464 		*__addr = __mem_in##bwlq(port);				\
465 		__addr++;						\
466 	}								\
467 }
468 
469 #define BUILDSTRING(bwlq, type)						\
470 									\
471 __BUILD_MEMORY_STRING(bwlq, type)					\
472 __BUILD_IOPORT_STRING(bwlq, type)
473 
474 BUILDSTRING(b, u8)
475 BUILDSTRING(w, u16)
476 BUILDSTRING(l, u32)
477 #ifdef CONFIG_64BIT
478 BUILDSTRING(q, u64)
479 #endif
480 
481 static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
482 {
483 	memset((void __force *) addr, val, count);
484 }
485 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
486 {
487 	memcpy(dst, (void __force *) src, count);
488 }
489 static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count)
490 {
491 	memcpy((void __force *) dst, src, count);
492 }
493 
494 /*
495  * The caches on some architectures aren't dma-coherent and have need to
496  * handle this in software.  There are three types of operations that
497  * can be applied to dma buffers.
498  *
499  *  - dma_cache_wback_inv(start, size) makes caches and coherent by
500  *    writing the content of the caches back to memory, if necessary.
501  *    The function also invalidates the affected part of the caches as
502  *    necessary before DMA transfers from outside to memory.
503  *  - dma_cache_wback(start, size) makes caches and coherent by
504  *    writing the content of the caches back to memory, if necessary.
505  *    The function also invalidates the affected part of the caches as
506  *    necessary before DMA transfers from outside to memory.
507  *  - dma_cache_inv(start, size) invalidates the affected parts of the
508  *    caches.  Dirty lines of the caches may be written back or simply
509  *    be discarded.  This operation is necessary before dma operations
510  *    to the memory.
511  *
512  * This API used to be exported; it now is for arch code internal use only.
513  */
514 #ifdef CONFIG_DMA_NONCOHERENT
515 
516 extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
517 extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
518 extern void (*_dma_cache_inv)(unsigned long start, unsigned long size);
519 
520 #define dma_cache_wback_inv(start, size)	_dma_cache_wback_inv(start, size)
521 #define dma_cache_wback(start, size)		_dma_cache_wback(start, size)
522 #define dma_cache_inv(start, size)		_dma_cache_inv(start, size)
523 
524 #else /* Sane hardware */
525 
526 #define dma_cache_wback_inv(start,size) \
527 	do { (void) (start); (void) (size); } while (0)
528 #define dma_cache_wback(start,size)	\
529 	do { (void) (start); (void) (size); } while (0)
530 #define dma_cache_inv(start,size)	\
531 	do { (void) (start); (void) (size); } while (0)
532 
533 #endif /* CONFIG_DMA_NONCOHERENT */
534 
535 /*
536  * Read a 32-bit register that requires a 64-bit read cycle on the bus.
537  * Avoid interrupt mucking, just adjust the address for 4-byte access.
538  * Assume the addresses are 8-byte aligned.
539  */
540 #ifdef __MIPSEB__
541 #define __CSR_32_ADJUST 4
542 #else
543 #define __CSR_32_ADJUST 0
544 #endif
545 
546 #define csr_out32(v, a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST) = (v))
547 #define csr_in32(a)    (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST))
548 
549 /*
550  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
551  * access
552  */
553 #define xlate_dev_mem_ptr(p)	__va(p)
554 
555 /*
556  * Convert a virtual cached pointer to an uncached pointer
557  */
558 #define xlate_dev_kmem_ptr(p)	p
559 
560 void __ioread64_copy(void *to, const void __iomem *from, size_t count);
561 
562 #endif /* _ASM_IO_H */
563