xref: /openbmc/linux/arch/mips/include/asm/io.h (revision f20c7d91)
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 #define IO_SPACE_LIMIT 0xffff
55 
56 /*
57  * On MIPS I/O ports are memory mapped, so we access them using normal
58  * load/store instructions. mips_io_port_base is the virtual address to
59  * which all ports are being mapped.  For sake of efficiency some code
60  * assumes that this is an address that can be loaded with a single lui
61  * instruction, so the lower 16 bits must be zero.  Should be true on
62  * on any sane architecture; generic code does not use this assumption.
63  */
64 extern unsigned long mips_io_port_base;
65 
66 static inline void set_io_port_base(unsigned long base)
67 {
68 	mips_io_port_base = base;
69 }
70 
71 /*
72  * Provide the necessary definitions for generic iomap. We make use of
73  * mips_io_port_base for iomap(), but we don't reserve any low addresses for
74  * use with I/O ports.
75  */
76 
77 #define HAVE_ARCH_PIO_SIZE
78 #define PIO_OFFSET	mips_io_port_base
79 #define PIO_MASK	IO_SPACE_LIMIT
80 #define PIO_RESERVED	0x0UL
81 
82 /*
83  * Enforce in-order execution of data I/O.  In the MIPS architecture
84  * these are equivalent to corresponding platform-specific memory
85  * barriers defined in <asm/barrier.h>.  API pinched from PowerPC,
86  * with sync additionally defined.
87  */
88 #define iobarrier_rw() mb()
89 #define iobarrier_r() rmb()
90 #define iobarrier_w() wmb()
91 #define iobarrier_sync() iob()
92 
93 /*
94  *     virt_to_phys    -       map virtual addresses to physical
95  *     @address: address to remap
96  *
97  *     The returned physical address is the physical (CPU) mapping for
98  *     the memory address given. It is only valid to use this function on
99  *     addresses directly mapped or allocated via kmalloc.
100  *
101  *     This function does not give bus mappings for DMA transfers. In
102  *     almost all conceivable cases a device driver should not be using
103  *     this function
104  */
105 static inline unsigned long virt_to_phys(volatile const void *address)
106 {
107 	return __pa(address);
108 }
109 
110 /*
111  *     phys_to_virt    -       map physical address to virtual
112  *     @address: address to remap
113  *
114  *     The returned virtual address is a current CPU mapping for
115  *     the memory address given. It is only valid to use this function on
116  *     addresses that have a kernel mapping
117  *
118  *     This function does not handle bus mappings for DMA transfers. In
119  *     almost all conceivable cases a device driver should not be using
120  *     this function
121  */
122 static inline void * phys_to_virt(unsigned long address)
123 {
124 	return (void *)(address + PAGE_OFFSET - PHYS_OFFSET);
125 }
126 
127 /*
128  * ISA I/O bus memory addresses are 1:1 with the physical address.
129  */
130 static inline unsigned long isa_virt_to_bus(volatile void *address)
131 {
132 	return virt_to_phys(address);
133 }
134 
135 static inline void *isa_bus_to_virt(unsigned long address)
136 {
137 	return phys_to_virt(address);
138 }
139 
140 /*
141  * However PCI ones are not necessarily 1:1 and therefore these interfaces
142  * are forbidden in portable PCI drivers.
143  *
144  * Allow them for x86 for legacy drivers, though.
145  */
146 #define virt_to_bus virt_to_phys
147 #define bus_to_virt phys_to_virt
148 
149 /*
150  * Change "struct page" to physical address.
151  */
152 #define page_to_phys(page)	((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
153 
154 void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
155 		unsigned long prot_val);
156 void iounmap(const volatile void __iomem *addr);
157 
158 /*
159  * ioremap     -   map bus memory into CPU space
160  * @offset:    bus address of the memory
161  * @size:      size of the resource to map
162  *
163  * ioremap performs a platform specific sequence of operations to
164  * make bus memory CPU accessible via the readb/readw/readl/writeb/
165  * writew/writel functions and the other mmio helpers. The returned
166  * address is not guaranteed to be usable directly as a virtual
167  * address.
168  */
169 #define ioremap(offset, size)						\
170 	ioremap_prot((offset), (size), _CACHE_UNCACHED)
171 #define ioremap_uc		ioremap
172 
173 /*
174  * ioremap_cache -	map bus memory into CPU space
175  * @offset:	    bus address of the memory
176  * @size:	    size of the resource to map
177  *
178  * ioremap_cache performs a platform specific sequence of operations to
179  * make bus memory CPU accessible via the readb/readw/readl/writeb/
180  * writew/writel functions and the other mmio helpers. The returned
181  * address is not guaranteed to be usable directly as a virtual
182  * address.
183  *
184  * This version of ioremap ensures that the memory is marked cachable by
185  * the CPU.  Also enables full write-combining.	 Useful for some
186  * memory-like regions on I/O busses.
187  */
188 #define ioremap_cache(offset, size)					\
189 	ioremap_prot((offset), (size), _page_cachable_default)
190 
191 /*
192  * ioremap_wc     -   map bus memory into CPU space
193  * @offset:    bus address of the memory
194  * @size:      size of the resource to map
195  *
196  * ioremap_wc performs a platform specific sequence of operations to
197  * make bus memory CPU accessible via the readb/readw/readl/writeb/
198  * writew/writel functions and the other mmio helpers. The returned
199  * address is not guaranteed to be usable directly as a virtual
200  * address.
201  *
202  * This version of ioremap ensures that the memory is marked uncachable
203  * but accelerated by means of write-combining feature. It is specifically
204  * useful for PCIe prefetchable windows, which may vastly improve a
205  * communications performance. If it was determined on boot stage, what
206  * CPU CCA doesn't support UCA, the method shall fall-back to the
207  * _CACHE_UNCACHED option (see cpu_probe() method).
208  */
209 #define ioremap_wc(offset, size)					\
210 	ioremap_prot((offset), (size), boot_cpu_data.writecombine)
211 
212 #if defined(CONFIG_CPU_CAVIUM_OCTEON) || defined(CONFIG_CPU_LOONGSON64)
213 #define war_io_reorder_wmb()		wmb()
214 #else
215 #define war_io_reorder_wmb()		barrier()
216 #endif
217 
218 #define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, barrier, relax, irq)	\
219 									\
220 static inline void pfx##write##bwlq(type val,				\
221 				    volatile void __iomem *mem)		\
222 {									\
223 	volatile type *__mem;						\
224 	type __val;							\
225 									\
226 	if (barrier)							\
227 		iobarrier_rw();						\
228 	else								\
229 		war_io_reorder_wmb();					\
230 									\
231 	__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));	\
232 									\
233 	__val = pfx##ioswab##bwlq(__mem, val);				\
234 									\
235 	if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
236 		*__mem = __val;						\
237 	else if (cpu_has_64bits) {					\
238 		unsigned long __flags;					\
239 		type __tmp;						\
240 									\
241 		if (irq)						\
242 			local_irq_save(__flags);			\
243 		__asm__ __volatile__(					\
244 			".set	push"		"\t\t# __writeq""\n\t"	\
245 			".set	arch=r4000"			"\n\t"	\
246 			"dsll32 %L0, %L0, 0"			"\n\t"	\
247 			"dsrl32 %L0, %L0, 0"			"\n\t"	\
248 			"dsll32 %M0, %M0, 0"			"\n\t"	\
249 			"or	%L0, %L0, %M0"			"\n\t"	\
250 			"sd	%L0, %2"			"\n\t"	\
251 			".set	pop"				"\n"	\
252 			: "=r" (__tmp)					\
253 			: "0" (__val), "m" (*__mem));			\
254 		if (irq)						\
255 			local_irq_restore(__flags);			\
256 	} else								\
257 		BUG();							\
258 }									\
259 									\
260 static inline type pfx##read##bwlq(const volatile void __iomem *mem)	\
261 {									\
262 	volatile type *__mem;						\
263 	type __val;							\
264 									\
265 	__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem));	\
266 									\
267 	if (barrier)							\
268 		iobarrier_rw();						\
269 									\
270 	if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
271 		__val = *__mem;						\
272 	else if (cpu_has_64bits) {					\
273 		unsigned long __flags;					\
274 									\
275 		if (irq)						\
276 			local_irq_save(__flags);			\
277 		__asm__ __volatile__(					\
278 			".set	push"		"\t\t# __readq" "\n\t"	\
279 			".set	arch=r4000"			"\n\t"	\
280 			"ld	%L0, %1"			"\n\t"	\
281 			"dsra32 %M0, %L0, 0"			"\n\t"	\
282 			"sll	%L0, %L0, 0"			"\n\t"	\
283 			".set	pop"				"\n"	\
284 			: "=r" (__val)					\
285 			: "m" (*__mem));				\
286 		if (irq)						\
287 			local_irq_restore(__flags);			\
288 	} else {							\
289 		__val = 0;						\
290 		BUG();							\
291 	}								\
292 									\
293 	/* prevent prefetching of coherent DMA data prematurely */	\
294 	if (!relax)							\
295 		rmb();							\
296 	return pfx##ioswab##bwlq(__mem, __val);				\
297 }
298 
299 #define __BUILD_IOPORT_SINGLE(pfx, bwlq, type, barrier, relax, p)	\
300 									\
301 static inline void pfx##out##bwlq##p(type val, unsigned long port)	\
302 {									\
303 	volatile type *__addr;						\
304 	type __val;							\
305 									\
306 	if (barrier)							\
307 		iobarrier_rw();						\
308 	else								\
309 		war_io_reorder_wmb();					\
310 									\
311 	__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
312 									\
313 	__val = pfx##ioswab##bwlq(__addr, val);				\
314 									\
315 	/* Really, we want this to be atomic */				\
316 	BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));		\
317 									\
318 	*__addr = __val;						\
319 }									\
320 									\
321 static inline type pfx##in##bwlq##p(unsigned long port)			\
322 {									\
323 	volatile type *__addr;						\
324 	type __val;							\
325 									\
326 	__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
327 									\
328 	BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long));		\
329 									\
330 	if (barrier)							\
331 		iobarrier_rw();						\
332 									\
333 	__val = *__addr;						\
334 									\
335 	/* prevent prefetching of coherent DMA data prematurely */	\
336 	if (!relax)							\
337 		rmb();							\
338 	return pfx##ioswab##bwlq(__addr, __val);			\
339 }
340 
341 #define __BUILD_MEMORY_PFX(bus, bwlq, type, relax)			\
342 									\
343 __BUILD_MEMORY_SINGLE(bus, bwlq, type, 1, relax, 1)
344 
345 #define BUILDIO_MEM(bwlq, type)						\
346 									\
347 __BUILD_MEMORY_PFX(__raw_, bwlq, type, 0)				\
348 __BUILD_MEMORY_PFX(__relaxed_, bwlq, type, 1)				\
349 __BUILD_MEMORY_PFX(__mem_, bwlq, type, 0)				\
350 __BUILD_MEMORY_PFX(, bwlq, type, 0)
351 
352 BUILDIO_MEM(b, u8)
353 BUILDIO_MEM(w, u16)
354 BUILDIO_MEM(l, u32)
355 #ifdef CONFIG_64BIT
356 BUILDIO_MEM(q, u64)
357 #else
358 __BUILD_MEMORY_PFX(__raw_, q, u64, 0)
359 __BUILD_MEMORY_PFX(__mem_, q, u64, 0)
360 #endif
361 
362 #define __BUILD_IOPORT_PFX(bus, bwlq, type)				\
363 	__BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0,)			\
364 	__BUILD_IOPORT_SINGLE(bus, bwlq, type, 1, 0, _p)
365 
366 #define BUILDIO_IOPORT(bwlq, type)					\
367 	__BUILD_IOPORT_PFX(, bwlq, type)				\
368 	__BUILD_IOPORT_PFX(__mem_, bwlq, type)
369 
370 BUILDIO_IOPORT(b, u8)
371 BUILDIO_IOPORT(w, u16)
372 BUILDIO_IOPORT(l, u32)
373 #ifdef CONFIG_64BIT
374 BUILDIO_IOPORT(q, u64)
375 #endif
376 
377 #define __BUILDIO(bwlq, type)						\
378 									\
379 __BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 1, 0, 0)
380 
381 __BUILDIO(q, u64)
382 
383 #define readb_relaxed			__relaxed_readb
384 #define readw_relaxed			__relaxed_readw
385 #define readl_relaxed			__relaxed_readl
386 #ifdef CONFIG_64BIT
387 #define readq_relaxed			__relaxed_readq
388 #endif
389 
390 #define writeb_relaxed			__relaxed_writeb
391 #define writew_relaxed			__relaxed_writew
392 #define writel_relaxed			__relaxed_writel
393 #ifdef CONFIG_64BIT
394 #define writeq_relaxed			__relaxed_writeq
395 #endif
396 
397 #define readb_be(addr)							\
398 	__raw_readb((__force unsigned *)(addr))
399 #define readw_be(addr)							\
400 	be16_to_cpu(__raw_readw((__force unsigned *)(addr)))
401 #define readl_be(addr)							\
402 	be32_to_cpu(__raw_readl((__force unsigned *)(addr)))
403 #define readq_be(addr)							\
404 	be64_to_cpu(__raw_readq((__force unsigned *)(addr)))
405 
406 #define writeb_be(val, addr)						\
407 	__raw_writeb((val), (__force unsigned *)(addr))
408 #define writew_be(val, addr)						\
409 	__raw_writew(cpu_to_be16((val)), (__force unsigned *)(addr))
410 #define writel_be(val, addr)						\
411 	__raw_writel(cpu_to_be32((val)), (__force unsigned *)(addr))
412 #define writeq_be(val, addr)						\
413 	__raw_writeq(cpu_to_be64((val)), (__force unsigned *)(addr))
414 
415 /*
416  * Some code tests for these symbols
417  */
418 #ifdef CONFIG_64BIT
419 #define readq				readq
420 #define writeq				writeq
421 #endif
422 
423 #define __BUILD_MEMORY_STRING(bwlq, type)				\
424 									\
425 static inline void writes##bwlq(volatile void __iomem *mem,		\
426 				const void *addr, unsigned int count)	\
427 {									\
428 	const volatile type *__addr = addr;				\
429 									\
430 	while (count--) {						\
431 		__mem_write##bwlq(*__addr, mem);			\
432 		__addr++;						\
433 	}								\
434 }									\
435 									\
436 static inline void reads##bwlq(volatile void __iomem *mem, void *addr,	\
437 			       unsigned int count)			\
438 {									\
439 	volatile type *__addr = addr;					\
440 									\
441 	while (count--) {						\
442 		*__addr = __mem_read##bwlq(mem);			\
443 		__addr++;						\
444 	}								\
445 }
446 
447 #define __BUILD_IOPORT_STRING(bwlq, type)				\
448 									\
449 static inline void outs##bwlq(unsigned long port, const void *addr,	\
450 			      unsigned int count)			\
451 {									\
452 	const volatile type *__addr = addr;				\
453 									\
454 	while (count--) {						\
455 		__mem_out##bwlq(*__addr, port);				\
456 		__addr++;						\
457 	}								\
458 }									\
459 									\
460 static inline void ins##bwlq(unsigned long port, void *addr,		\
461 			     unsigned int count)			\
462 {									\
463 	volatile type *__addr = addr;					\
464 									\
465 	while (count--) {						\
466 		*__addr = __mem_in##bwlq(port);				\
467 		__addr++;						\
468 	}								\
469 }
470 
471 #define BUILDSTRING(bwlq, type)						\
472 									\
473 __BUILD_MEMORY_STRING(bwlq, type)					\
474 __BUILD_IOPORT_STRING(bwlq, type)
475 
476 BUILDSTRING(b, u8)
477 BUILDSTRING(w, u16)
478 BUILDSTRING(l, u32)
479 #ifdef CONFIG_64BIT
480 BUILDSTRING(q, u64)
481 #endif
482 
483 static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
484 {
485 	memset((void __force *) addr, val, count);
486 }
487 static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
488 {
489 	memcpy(dst, (void __force *) src, count);
490 }
491 static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count)
492 {
493 	memcpy((void __force *) dst, src, count);
494 }
495 
496 /*
497  * The caches on some architectures aren't dma-coherent and have need to
498  * handle this in software.  There are three types of operations that
499  * can be applied to dma buffers.
500  *
501  *  - dma_cache_wback_inv(start, size) makes caches and coherent by
502  *    writing the content of the caches back to memory, if necessary.
503  *    The function also invalidates the affected part of the caches as
504  *    necessary before DMA transfers from outside to memory.
505  *  - dma_cache_wback(start, size) makes caches and coherent by
506  *    writing the content of the caches back to memory, if necessary.
507  *    The function also invalidates the affected part of the caches as
508  *    necessary before DMA transfers from outside to memory.
509  *  - dma_cache_inv(start, size) invalidates the affected parts of the
510  *    caches.  Dirty lines of the caches may be written back or simply
511  *    be discarded.  This operation is necessary before dma operations
512  *    to the memory.
513  *
514  * This API used to be exported; it now is for arch code internal use only.
515  */
516 #ifdef CONFIG_DMA_NONCOHERENT
517 
518 extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
519 extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
520 extern void (*_dma_cache_inv)(unsigned long start, unsigned long size);
521 
522 #define dma_cache_wback_inv(start, size)	_dma_cache_wback_inv(start, size)
523 #define dma_cache_wback(start, size)		_dma_cache_wback(start, size)
524 #define dma_cache_inv(start, size)		_dma_cache_inv(start, size)
525 
526 #else /* Sane hardware */
527 
528 #define dma_cache_wback_inv(start,size) \
529 	do { (void) (start); (void) (size); } while (0)
530 #define dma_cache_wback(start,size)	\
531 	do { (void) (start); (void) (size); } while (0)
532 #define dma_cache_inv(start,size)	\
533 	do { (void) (start); (void) (size); } while (0)
534 
535 #endif /* CONFIG_DMA_NONCOHERENT */
536 
537 /*
538  * Read a 32-bit register that requires a 64-bit read cycle on the bus.
539  * Avoid interrupt mucking, just adjust the address for 4-byte access.
540  * Assume the addresses are 8-byte aligned.
541  */
542 #ifdef __MIPSEB__
543 #define __CSR_32_ADJUST 4
544 #else
545 #define __CSR_32_ADJUST 0
546 #endif
547 
548 #define csr_out32(v, a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST) = (v))
549 #define csr_in32(a)    (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST))
550 
551 /*
552  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
553  * access
554  */
555 #define xlate_dev_mem_ptr(p)	__va(p)
556 
557 /*
558  * Convert a virtual cached pointer to an uncached pointer
559  */
560 #define xlate_dev_kmem_ptr(p)	p
561 
562 void __ioread64_copy(void *to, const void __iomem *from, size_t count);
563 
564 #endif /* _ASM_IO_H */
565