xref: /openbmc/linux/arch/mips/include/asm/io.h (revision db66795f)
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_nodebug(volatile const void *address)
104 {
105 	return __pa(address);
106 }
107 
108 #ifdef CONFIG_DEBUG_VIRTUAL
109 extern phys_addr_t __virt_to_phys(volatile const void *x);
110 #else
111 #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
112 #endif
113 
114 #define virt_to_phys virt_to_phys
115 static inline phys_addr_t virt_to_phys(const volatile void *x)
116 {
117 	return __virt_to_phys(x);
118 }
119 
120 /*
121  *     phys_to_virt    -       map physical address to virtual
122  *     @address: address to remap
123  *
124  *     The returned virtual address is a current CPU mapping for
125  *     the memory address given. It is only valid to use this function on
126  *     addresses that have a kernel mapping
127  *
128  *     This function does not handle bus mappings for DMA transfers. In
129  *     almost all conceivable cases a device driver should not be using
130  *     this function
131  */
132 static inline void * phys_to_virt(unsigned long address)
133 {
134 	return __va(address);
135 }
136 
137 /*
138  * ISA I/O bus memory addresses are 1:1 with the physical address.
139  */
140 static inline unsigned long isa_virt_to_bus(volatile void *address)
141 {
142 	return virt_to_phys(address);
143 }
144 
145 static inline void *isa_bus_to_virt(unsigned long address)
146 {
147 	return phys_to_virt(address);
148 }
149 
150 /*
151  * Change "struct page" to physical address.
152  */
153 #define page_to_phys(page)	((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
154 
155 void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
156 		unsigned long prot_val);
157 void iounmap(const volatile void __iomem *addr);
158 
159 /*
160  * ioremap     -   map bus memory into CPU space
161  * @offset:    bus address of the memory
162  * @size:      size of the resource to map
163  *
164  * ioremap performs a platform specific sequence of operations to
165  * make bus memory CPU accessible via the readb/readw/readl/writeb/
166  * writew/writel functions and the other mmio helpers. The returned
167  * address is not guaranteed to be usable directly as a virtual
168  * address.
169  */
170 #define ioremap(offset, size)						\
171 	ioremap_prot((offset), (size), _CACHE_UNCACHED)
172 #define ioremap_uc		ioremap
173 
174 /*
175  * ioremap_cache -	map bus memory into CPU space
176  * @offset:	    bus address of the memory
177  * @size:	    size of the resource to map
178  *
179  * ioremap_cache performs a platform specific sequence of operations to
180  * make bus memory CPU accessible via the readb/readw/readl/writeb/
181  * writew/writel functions and the other mmio helpers. The returned
182  * address is not guaranteed to be usable directly as a virtual
183  * address.
184  *
185  * This version of ioremap ensures that the memory is marked cachable by
186  * the CPU.  Also enables full write-combining.	 Useful for some
187  * memory-like regions on I/O busses.
188  */
189 #define ioremap_cache(offset, size)					\
190 	ioremap_prot((offset), (size), _page_cachable_default)
191 
192 /*
193  * ioremap_wc     -   map bus memory into CPU space
194  * @offset:    bus address of the memory
195  * @size:      size of the resource to map
196  *
197  * ioremap_wc performs a platform specific sequence of operations to
198  * make bus memory CPU accessible via the readb/readw/readl/writeb/
199  * writew/writel functions and the other mmio helpers. The returned
200  * address is not guaranteed to be usable directly as a virtual
201  * address.
202  *
203  * This version of ioremap ensures that the memory is marked uncachable
204  * but accelerated by means of write-combining feature. It is specifically
205  * useful for PCIe prefetchable windows, which may vastly improve a
206  * communications performance. If it was determined on boot stage, what
207  * CPU CCA doesn't support UCA, the method shall fall-back to the
208  * _CACHE_UNCACHED option (see cpu_probe() method).
209  */
210 #define ioremap_wc(offset, size)					\
211 	ioremap_prot((offset), (size), boot_cpu_data.writecombine)
212 
213 #if defined(CONFIG_CPU_CAVIUM_OCTEON)
214 #define war_io_reorder_wmb()		wmb()
215 #else
216 #define war_io_reorder_wmb()		barrier()
217 #endif
218 
219 #define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, barrier, relax, irq)	\
220 									\
221 static inline void pfx##write##bwlq(type val,				\
222 				    volatile void __iomem *mem)		\
223 {									\
224 	volatile type *__mem;						\
225 	type __val;							\
226 									\
227 	if (barrier)							\
228 		iobarrier_rw();						\
229 	else								\
230 		war_io_reorder_wmb();					\
231 									\
232 	__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));	\
233 									\
234 	__val = pfx##ioswab##bwlq(__mem, val);				\
235 									\
236 	if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
237 		*__mem = __val;						\
238 	else if (cpu_has_64bits) {					\
239 		unsigned long __flags;					\
240 		type __tmp;						\
241 									\
242 		if (irq)						\
243 			local_irq_save(__flags);			\
244 		__asm__ __volatile__(					\
245 			".set	push"		"\t\t# __writeq""\n\t"	\
246 			".set	arch=r4000"			"\n\t"	\
247 			"dsll32 %L0, %L0, 0"			"\n\t"	\
248 			"dsrl32 %L0, %L0, 0"			"\n\t"	\
249 			"dsll32 %M0, %M0, 0"			"\n\t"	\
250 			"or	%L0, %L0, %M0"			"\n\t"	\
251 			"sd	%L0, %2"			"\n\t"	\
252 			".set	pop"				"\n"	\
253 			: "=r" (__tmp)					\
254 			: "0" (__val), "m" (*__mem));			\
255 		if (irq)						\
256 			local_irq_restore(__flags);			\
257 	} else								\
258 		BUG();							\
259 }									\
260 									\
261 static inline type pfx##read##bwlq(const volatile void __iomem *mem)	\
262 {									\
263 	volatile type *__mem;						\
264 	type __val;							\
265 									\
266 	__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));	\
267 									\
268 	if (barrier)							\
269 		iobarrier_rw();						\
270 									\
271 	if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
272 		__val = *__mem;						\
273 	else if (cpu_has_64bits) {					\
274 		unsigned long __flags;					\
275 									\
276 		if (irq)						\
277 			local_irq_save(__flags);			\
278 		__asm__ __volatile__(					\
279 			".set	push"		"\t\t# __readq" "\n\t"	\
280 			".set	arch=r4000"			"\n\t"	\
281 			"ld	%L0, %1"			"\n\t"	\
282 			"dsra32 %M0, %L0, 0"			"\n\t"	\
283 			"sll	%L0, %L0, 0"			"\n\t"	\
284 			".set	pop"				"\n"	\
285 			: "=r" (__val)					\
286 			: "m" (*__mem));				\
287 		if (irq)						\
288 			local_irq_restore(__flags);			\
289 	} else {							\
290 		__val = 0;						\
291 		BUG();							\
292 	}								\
293 									\
294 	/* prevent prefetching of coherent DMA data prematurely */	\
295 	if (!relax)							\
296 		rmb();							\
297 	return pfx##ioswab##bwlq(__mem, __val);				\
298 }
299 
300 #define __BUILD_IOPORT_SINGLE(pfx, bwlq, type, barrier, relax, p)	\
301 									\
302 static inline void pfx##out##bwlq##p(type val, unsigned long port)	\
303 {									\
304 	volatile type *__addr;						\
305 	type __val;							\
306 									\
307 	if (barrier)							\
308 		iobarrier_rw();						\
309 	else								\
310 		war_io_reorder_wmb();					\
311 									\
312 	__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
313 									\
314 	__val = pfx##ioswab##bwlq(__addr, val);				\
315 									\
316 	/* Really, we want this to be atomic */				\
317 	BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));		\
318 									\
319 	*__addr = __val;						\
320 }									\
321 									\
322 static inline type pfx##in##bwlq##p(unsigned long port)			\
323 {									\
324 	volatile type *__addr;						\
325 	type __val;							\
326 									\
327 	__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
328 									\
329 	BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));		\
330 									\
331 	if (barrier)							\
332 		iobarrier_rw();						\
333 									\
334 	__val = *__addr;						\
335 									\
336 	/* prevent prefetching of coherent DMA data prematurely */	\
337 	if (!relax)							\
338 		rmb();							\
339 	return pfx##ioswab##bwlq(__addr, __val);			\
340 }
341 
342 #define __BUILD_MEMORY_PFX(bus, bwlq, type, relax)			\
343 									\
344 __BUILD_MEMORY_SINGLE(bus, bwlq, type, 1, relax, 1)
345 
346 #define BUILDIO_MEM(bwlq, type)						\
347 									\
348 __BUILD_MEMORY_PFX(__raw_, bwlq, type, 0)				\
349 __BUILD_MEMORY_PFX(__relaxed_, bwlq, type, 1)				\
350 __BUILD_MEMORY_PFX(__mem_, bwlq, type, 0)				\
351 __BUILD_MEMORY_PFX(, bwlq, type, 0)
352 
353 BUILDIO_MEM(b, u8)
354 BUILDIO_MEM(w, u16)
355 BUILDIO_MEM(l, u32)
356 #ifdef CONFIG_64BIT
357 BUILDIO_MEM(q, u64)
358 #else
359 __BUILD_MEMORY_PFX(__raw_, q, u64, 0)
360 __BUILD_MEMORY_PFX(__mem_, q, u64, 0)
361 #endif
362 
363 #define __BUILD_IOPORT_PFX(bus, bwlq, type)				\
364 	__BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0,)			\
365 	__BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0, _p)
366 
367 #define BUILDIO_IOPORT(bwlq, type)					\
368 	__BUILD_IOPORT_PFX(, bwlq, type)				\
369 	__BUILD_IOPORT_PFX(__mem_, bwlq, type)
370 
371 BUILDIO_IOPORT(b, u8)
372 BUILDIO_IOPORT(w, u16)
373 BUILDIO_IOPORT(l, u32)
374 #ifdef CONFIG_64BIT
375 BUILDIO_IOPORT(q, u64)
376 #endif
377 
378 #define __BUILDIO(bwlq, type)						\
379 									\
380 __BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 1, 0, 0)
381 
382 __BUILDIO(q, u64)
383 
384 #define readb_relaxed			__relaxed_readb
385 #define readw_relaxed			__relaxed_readw
386 #define readl_relaxed			__relaxed_readl
387 #ifdef CONFIG_64BIT
388 #define readq_relaxed			__relaxed_readq
389 #endif
390 
391 #define writeb_relaxed			__relaxed_writeb
392 #define writew_relaxed			__relaxed_writew
393 #define writel_relaxed			__relaxed_writel
394 #ifdef CONFIG_64BIT
395 #define writeq_relaxed			__relaxed_writeq
396 #endif
397 
398 #define readb_be(addr)							\
399 	__raw_readb((__force unsigned *)(addr))
400 #define readw_be(addr)							\
401 	be16_to_cpu(__raw_readw((__force unsigned *)(addr)))
402 #define readl_be(addr)							\
403 	be32_to_cpu(__raw_readl((__force unsigned *)(addr)))
404 #define readq_be(addr)							\
405 	be64_to_cpu(__raw_readq((__force unsigned *)(addr)))
406 
407 #define writeb_be(val, addr)						\
408 	__raw_writeb((val), (__force unsigned *)(addr))
409 #define writew_be(val, addr)						\
410 	__raw_writew(cpu_to_be16((val)), (__force unsigned *)(addr))
411 #define writel_be(val, addr)						\
412 	__raw_writel(cpu_to_be32((val)), (__force unsigned *)(addr))
413 #define writeq_be(val, addr)						\
414 	__raw_writeq(cpu_to_be64((val)), (__force unsigned *)(addr))
415 
416 /*
417  * Some code tests for these symbols
418  */
419 #ifdef CONFIG_64BIT
420 #define readq				readq
421 #define writeq				writeq
422 #endif
423 
424 #define __BUILD_MEMORY_STRING(bwlq, type)				\
425 									\
426 static inline void writes##bwlq(volatile void __iomem *mem,		\
427 				const void *addr, unsigned int count)	\
428 {									\
429 	const volatile type *__addr = addr;				\
430 									\
431 	while (count--) {						\
432 		__mem_write##bwlq(*__addr, mem);			\
433 		__addr++;						\
434 	}								\
435 }									\
436 									\
437 static inline void reads##bwlq(volatile void __iomem *mem, void *addr,	\
438 			       unsigned int count)			\
439 {									\
440 	volatile type *__addr = addr;					\
441 									\
442 	while (count--) {						\
443 		*__addr = __mem_read##bwlq(mem);			\
444 		__addr++;						\
445 	}								\
446 }
447 
448 #define __BUILD_IOPORT_STRING(bwlq, type)				\
449 									\
450 static inline void outs##bwlq(unsigned long port, const void *addr,	\
451 			      unsigned int count)			\
452 {									\
453 	const volatile type *__addr = addr;				\
454 									\
455 	while (count--) {						\
456 		__mem_out##bwlq(*__addr, port);				\
457 		__addr++;						\
458 	}								\
459 }									\
460 									\
461 static inline void ins##bwlq(unsigned long port, void *addr,		\
462 			     unsigned int count)			\
463 {									\
464 	volatile type *__addr = addr;					\
465 									\
466 	while (count--) {						\
467 		*__addr = __mem_in##bwlq(port);				\
468 		__addr++;						\
469 	}								\
470 }
471 
472 #define BUILDSTRING(bwlq, type)						\
473 									\
474 __BUILD_MEMORY_STRING(bwlq, type)					\
475 __BUILD_IOPORT_STRING(bwlq, type)
476 
477 BUILDSTRING(b, u8)
478 BUILDSTRING(w, u16)
479 BUILDSTRING(l, u32)
480 #ifdef CONFIG_64BIT
481 BUILDSTRING(q, u64)
482 #endif
483 
484 static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
485 {
486 	memset((void __force *) addr, val, count);
487 }
488 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
489 {
490 	memcpy(dst, (void __force *) src, count);
491 }
492 static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count)
493 {
494 	memcpy((void __force *) dst, src, count);
495 }
496 
497 /*
498  * The caches on some architectures aren't dma-coherent and have need to
499  * handle this in software.  There are three types of operations that
500  * can be applied to dma buffers.
501  *
502  *  - dma_cache_wback_inv(start, size) makes caches and coherent by
503  *    writing the content of the caches back to memory, if necessary.
504  *    The function also invalidates the affected part of the caches as
505  *    necessary before DMA transfers from outside to memory.
506  *  - dma_cache_wback(start, size) makes caches and coherent by
507  *    writing the content of the caches back to memory, if necessary.
508  *    The function also invalidates the affected part of the caches as
509  *    necessary before DMA transfers from outside to memory.
510  *  - dma_cache_inv(start, size) invalidates the affected parts of the
511  *    caches.  Dirty lines of the caches may be written back or simply
512  *    be discarded.  This operation is necessary before dma operations
513  *    to the memory.
514  *
515  * This API used to be exported; it now is for arch code internal use only.
516  */
517 #ifdef CONFIG_DMA_NONCOHERENT
518 
519 extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
520 extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
521 extern void (*_dma_cache_inv)(unsigned long start, unsigned long size);
522 
523 #define dma_cache_wback_inv(start, size)	_dma_cache_wback_inv(start, size)
524 #define dma_cache_wback(start, size)		_dma_cache_wback(start, size)
525 #define dma_cache_inv(start, size)		_dma_cache_inv(start, size)
526 
527 #else /* Sane hardware */
528 
529 #define dma_cache_wback_inv(start,size) \
530 	do { (void) (start); (void) (size); } while (0)
531 #define dma_cache_wback(start,size)	\
532 	do { (void) (start); (void) (size); } while (0)
533 #define dma_cache_inv(start,size)	\
534 	do { (void) (start); (void) (size); } while (0)
535 
536 #endif /* CONFIG_DMA_NONCOHERENT */
537 
538 /*
539  * Read a 32-bit register that requires a 64-bit read cycle on the bus.
540  * Avoid interrupt mucking, just adjust the address for 4-byte access.
541  * Assume the addresses are 8-byte aligned.
542  */
543 #ifdef __MIPSEB__
544 #define __CSR_32_ADJUST 4
545 #else
546 #define __CSR_32_ADJUST 0
547 #endif
548 
549 #define csr_out32(v, a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST) = (v))
550 #define csr_in32(a)    (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST))
551 
552 /*
553  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
554  * access
555  */
556 #define xlate_dev_mem_ptr(p)	__va(p)
557 #define unxlate_dev_mem_ptr(p, v) do { } while (0)
558 
559 void __ioread64_copy(void *to, const void __iomem *from, size_t count);
560 
561 #endif /* _ASM_IO_H */
562