xref: /kernel/linux/linux-5.10/arch/mips/include/asm/io.h (revision 8c2ecf20)
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 */
62extern unsigned long mips_io_port_base;
63
64static 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 */
103static 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 */
120static 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 */
128static inline unsigned long isa_virt_to_bus(volatile void *address)
129{
130	return virt_to_phys(address);
131}
132
133static 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
152void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
153		unsigned long prot_val);
154void 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									\
218static 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									\
258static 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									\
299static 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									\
319static 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
350BUILDIO_MEM(b, u8)
351BUILDIO_MEM(w, u16)
352BUILDIO_MEM(l, u32)
353#ifdef CONFIG_64BIT
354BUILDIO_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
368BUILDIO_IOPORT(b, u8)
369BUILDIO_IOPORT(w, u16)
370BUILDIO_IOPORT(l, u32)
371#ifdef CONFIG_64BIT
372BUILDIO_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									\
423static 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									\
434static 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									\
447static 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									\
458static 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
474BUILDSTRING(b, u8)
475BUILDSTRING(w, u16)
476BUILDSTRING(l, u32)
477#ifdef CONFIG_64BIT
478BUILDSTRING(q, u64)
479#endif
480
481static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
482{
483	memset((void __force *) addr, val, count);
484}
485static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
486{
487	memcpy(dst, (void __force *) src, count);
488}
489static 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
516extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
517extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
518extern 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
560void __ioread64_copy(void *to, const void __iomem *from, size_t count);
561
562#endif /* _ASM_IO_H */
563