xref: /linux/arch/arm/include/asm/io.h (revision bba2c3615bd6cfee7456d1130f2e6b01b3f4e9ba)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  *  arch/arm/include/asm/io.h
4  *
5  *  Copyright (C) 1996-2000 Russell King
6  *
7  * Modifications:
8  *  16-Sep-1996	RMK	Inlined the inx/outx functions & optimised for both
9  *			constant addresses and variable addresses.
10  *  04-Dec-1997	RMK	Moved a lot of this stuff to the new architecture
11  *			specific IO header files.
12  *  27-Mar-1999	PJB	Second parameter of memcpy_toio is const..
13  *  04-Apr-1999	PJB	Added check_signature.
14  *  12-Dec-1999	RMK	More cleanups
15  *  18-Jun-2000 RMK	Removed virt_to_* and friends definitions
16  *  05-Oct-2004 BJD     Moved memory string functions to use void __iomem
17  */
18 #ifndef __ASM_ARM_IO_H
19 #define __ASM_ARM_IO_H
20 
21 #ifdef __KERNEL__
22 
23 #include <linux/string.h>
24 #include <linux/types.h>
25 #include <asm/byteorder.h>
26 #include <asm/page.h>
27 #include <asm-generic/pci_iomap.h>
28 
29 /*
30  * ISA I/O bus memory addresses are 1:1 with the physical address.
31  */
32 #define isa_virt_to_bus virt_to_phys
33 #define isa_bus_to_virt phys_to_virt
34 
35 /*
36  * Atomic MMIO-wide IO modify
37  */
38 extern void atomic_io_modify(void __iomem *reg, u32 mask, u32 set);
39 extern void atomic_io_modify_relaxed(void __iomem *reg, u32 mask, u32 set);
40 
41 /*
42  * Generic IO read/write.  These perform native-endian accesses.  Note
43  * that some architectures will want to re-define __raw_{read,write}w.
44  */
45 void __raw_writesb(volatile void __iomem *addr, const void *data, int bytelen);
46 void __raw_writesw(volatile void __iomem *addr, const void *data, int wordlen);
47 void __raw_writesl(volatile void __iomem *addr, const void *data, int longlen);
48 
49 void __raw_readsb(const volatile void __iomem *addr, void *data, int bytelen);
50 void __raw_readsw(const volatile void __iomem *addr, void *data, int wordlen);
51 void __raw_readsl(const volatile void __iomem *addr, void *data, int longlen);
52 
53 #if __LINUX_ARM_ARCH__ < 6
54 /*
55  * Half-word accesses are problematic with RiscPC due to limitations of
56  * the bus. Rather than special-case the machine, just let the compiler
57  * generate the access for CPUs prior to ARMv6.
58  */
59 #define __raw_writew __raw_writew
60 static __no_kasan_or_inline void __raw_writew(u16 val, volatile void __iomem *addr)
61 {
62 	__chk_io_ptr(addr);
63 	*(volatile unsigned short __force *)addr = val;
64 }
65 
66 #define __raw_readw __raw_readw
67 static __no_kasan_or_inline u16 __raw_readw(const volatile void __iomem *addr)
68 {
69 	__chk_io_ptr(addr);
70 	return *(const volatile unsigned short __force *)addr;
71 }
72 #else
73 /*
74  * When running under a hypervisor, we want to avoid I/O accesses with
75  * writeback addressing modes as these incur a significant performance
76  * overhead (the address generation must be emulated in software).
77  */
78 #define __raw_writew __raw_writew
79 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
80 {
81 	asm volatile("strh %1, %0"
82 		     : : "Q" (*(volatile u16 __force *)addr), "r" (val));
83 }
84 
85 #define __raw_readw __raw_readw
86 static inline u16 __raw_readw(const volatile void __iomem *addr)
87 {
88 	u16 val;
89 	asm volatile("ldrh %0, %1"
90 		     : "=r" (val)
91 		     : "Q" (*(volatile u16 __force *)addr));
92 	return val;
93 }
94 #endif
95 
96 #define __raw_writeb __raw_writeb
97 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
98 {
99 	asm volatile("strb %1, %0"
100 		     : : "Qo" (*(volatile u8 __force *)addr), "r" (val));
101 }
102 
103 #define __raw_writel __raw_writel
104 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
105 {
106 	asm volatile("str %1, %0"
107 		     : : "Qo" (*(volatile u32 __force *)addr), "r" (val));
108 }
109 
110 #define __raw_readb __raw_readb
111 static inline u8 __raw_readb(const volatile void __iomem *addr)
112 {
113 	u8 val;
114 	asm volatile("ldrb %0, %1"
115 		     : "=r" (val)
116 		     : "Qo" (*(volatile u8 __force *)addr));
117 	return val;
118 }
119 
120 #define __raw_readl __raw_readl
121 static inline u32 __raw_readl(const volatile void __iomem *addr)
122 {
123 	u32 val;
124 	asm volatile("ldr %0, %1"
125 		     : "=r" (val)
126 		     : "Qo" (*(volatile u32 __force *)addr));
127 	return val;
128 }
129 
130 /*
131  * Architecture ioremap implementation.
132  */
133 #define MT_DEVICE		0
134 #define MT_DEVICE_NONSHARED	1
135 #define MT_DEVICE_CACHED	2
136 #define MT_DEVICE_WC		3
137 /*
138  * types 4 onwards can be found in asm/mach/map.h and are undefined
139  * for ioremap
140  */
141 
142 /*
143  * __arm_ioremap takes CPU physical address.
144  * __arm_ioremap_pfn takes a Page Frame Number and an offset into that page
145  * The _caller variety takes a __builtin_return_address(0) value for
146  * /proc/vmalloc to use - and should only be used in non-inline functions.
147  */
148 extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
149 	void *);
150 extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
151 extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
152 void __arm_iomem_set_ro(void __iomem *ptr, size_t size);
153 
154 extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
155 	unsigned int, void *);
156 
157 /*
158  * Bad read/write accesses...
159  */
160 extern void __readwrite_bug(const char *fn);
161 
162 /*
163  * A typesafe __io() helper
164  */
165 static inline void __iomem *__typesafe_io(unsigned long addr)
166 {
167 	return (void __iomem *)addr;
168 }
169 
170 #define IOMEM(x)	((void __force __iomem *)(x))
171 
172 /* IO barriers */
173 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
174 #include <asm/barrier.h>
175 #define __iormb()		rmb()
176 #define __iowmb()		wmb()
177 #else
178 #define __iormb()		do { } while (0)
179 #define __iowmb()		do { } while (0)
180 #endif
181 
182 /* PCI fixed i/o mapping */
183 #define PCI_IO_VIRT_BASE	0xfee00000
184 #define PCI_IOBASE		((void __iomem *)PCI_IO_VIRT_BASE)
185 
186 #if defined(CONFIG_PCI) || IS_ENABLED(CONFIG_PCMCIA)
187 void pci_ioremap_set_mem_type(int mem_type);
188 #else
189 static inline void pci_ioremap_set_mem_type(int mem_type) {}
190 #endif
191 
192 struct resource;
193 
194 #define pci_remap_iospace pci_remap_iospace
195 int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
196 
197 /*
198  * PCI configuration space mapping function.
199  *
200  * The PCI specification does not allow configuration write
201  * transactions to be posted. Add an arch specific
202  * pci_remap_cfgspace() definition that is implemented
203  * through strongly ordered memory mappings.
204  */
205 #define pci_remap_cfgspace pci_remap_cfgspace
206 void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size);
207 /*
208  * Now, pick up the machine-defined IO definitions
209  */
210 #ifdef CONFIG_NEED_MACH_IO_H
211 #include <mach/io.h>
212 #else
213 #if IS_ENABLED(CONFIG_PCMCIA) || defined(CONFIG_PCI)
214 #define IO_SPACE_LIMIT	((resource_size_t)0xfffff)
215 #else
216 #define IO_SPACE_LIMIT ((resource_size_t)0)
217 #endif
218 #define __io(a)		__typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
219 #endif
220 
221 /*
222  *  IO port access primitives
223  *  -------------------------
224  *
225  * The ARM doesn't have special IO access instructions; all IO is memory
226  * mapped.  Note that these are defined to perform little endian accesses
227  * only.  Their primary purpose is to access PCI and ISA peripherals.
228  *
229  * Note that for a big endian machine, this implies that the following
230  * big endian mode connectivity is in place, as described by numerous
231  * ARM documents:
232  *
233  *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
234  *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
235  *
236  * The machine specific io.h include defines __io to translate an "IO"
237  * address to a memory address.
238  *
239  * Note that we prevent GCC re-ordering or caching values in expressions
240  * by introducing sequence points into the in*() definitions.  Note that
241  * __raw_* do not guarantee this behaviour.
242  *
243  * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
244  */
245 #ifdef __io
246 #define outb(v,p)	({ __iowmb(); __raw_writeb(v,__io(p)); })
247 #define outw(v,p)	({ __iowmb(); __raw_writew((__force __u16) \
248 					cpu_to_le16(v),__io(p)); })
249 #define outl(v,p)	({ __iowmb(); __raw_writel((__force __u32) \
250 					cpu_to_le32(v),__io(p)); })
251 
252 #define inb(p)	({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
253 #define inw(p)	({ __u16 __v = le16_to_cpu((__force __le16) \
254 			__raw_readw(__io(p))); __iormb(); __v; })
255 #define inl(p)	({ __u32 __v = le32_to_cpu((__force __le32) \
256 			__raw_readl(__io(p))); __iormb(); __v; })
257 
258 #define outsb(p,d,l)		__raw_writesb(__io(p),d,l)
259 #define outsw(p,d,l)		__raw_writesw(__io(p),d,l)
260 #define outsl(p,d,l)		__raw_writesl(__io(p),d,l)
261 
262 #define insb(p,d,l)		__raw_readsb(__io(p),d,l)
263 #define insw(p,d,l)		__raw_readsw(__io(p),d,l)
264 #define insl(p,d,l)		__raw_readsl(__io(p),d,l)
265 #endif
266 
267 /*
268  * String version of IO memory access ops:
269  */
270 extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
271 extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
272 extern void _memset_io(volatile void __iomem *, int, size_t);
273 
274 /*
275  *  Memory access primitives
276  *  ------------------------
277  *
278  * These perform PCI memory accesses via an ioremap region.  They don't
279  * take an address as such, but a cookie.
280  *
281  * Again, these are defined to perform little endian accesses.  See the
282  * IO port primitives for more information.
283  */
284 #ifndef readl
285 #define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
286 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
287 					__raw_readw(c)); __r; })
288 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
289 					__raw_readl(c)); __r; })
290 
291 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
292 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
293 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
294 
295 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
296 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
297 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
298 
299 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
300 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
301 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
302 
303 #define readsb(p,d,l)		__raw_readsb(p,d,l)
304 #define readsw(p,d,l)		__raw_readsw(p,d,l)
305 #define readsl(p,d,l)		__raw_readsl(p,d,l)
306 
307 #define writesb(p,d,l)		__raw_writesb(p,d,l)
308 #define writesw(p,d,l)		__raw_writesw(p,d,l)
309 #define writesl(p,d,l)		__raw_writesl(p,d,l)
310 
311 #ifndef __ARMBE__
312 static inline void memset_io(volatile void __iomem *dst, unsigned c,
313 	size_t count)
314 {
315 	extern void mmioset(void *, unsigned int, size_t);
316 	mmioset((void __force *)dst, c, count);
317 }
318 #define memset_io(dst,c,count) memset_io(dst,c,count)
319 
320 static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
321 	size_t count)
322 {
323 	extern void mmiocpy(void *, const void *, size_t);
324 	mmiocpy(to, (const void __force *)from, count);
325 }
326 #define memcpy_fromio(to,from,count) memcpy_fromio(to,from,count)
327 
328 static inline void memcpy_toio(volatile void __iomem *to, const void *from,
329 	size_t count)
330 {
331 	extern void mmiocpy(void *, const void *, size_t);
332 	mmiocpy((void __force *)to, from, count);
333 }
334 #define memcpy_toio(to,from,count) memcpy_toio(to,from,count)
335 
336 #else
337 #define memset_io(c,v,l)	_memset_io(c,(v),(l))
338 #define memcpy_fromio(a,c,l)	_memcpy_fromio((a),c,(l))
339 #define memcpy_toio(c,a,l)	_memcpy_toio(c,(a),(l))
340 #endif
341 
342 #endif	/* readl */
343 
344 /*
345  * ioremap() and friends.
346  *
347  * ioremap() takes a resource address, and size.  Due to the ARM memory
348  * types, it is important to use the correct ioremap() function as each
349  * mapping has specific properties.
350  *
351  * Function		Memory type	Cacheability	Cache hint
352  * ioremap()		Device		n/a		n/a
353  * ioremap_cache()	Normal		Writeback	Read allocate
354  * ioremap_wc()		Normal		Non-cacheable	n/a
355  * ioremap_wt()		Normal		Non-cacheable	n/a
356  *
357  * All device mappings have the following properties:
358  * - no access speculation
359  * - no repetition (eg, on return from an exception)
360  * - number, order and size of accesses are maintained
361  * - unaligned accesses are "unpredictable"
362  * - writes may be delayed before they hit the endpoint device
363  *
364  * All normal memory mappings have the following properties:
365  * - reads can be repeated with no side effects
366  * - repeated reads return the last value written
367  * - reads can fetch additional locations without side effects
368  * - writes can be repeated (in certain cases) with no side effects
369  * - writes can be merged before accessing the target
370  * - unaligned accesses can be supported
371  * - ordering is not guaranteed without explicit dependencies or barrier
372  *   instructions
373  * - writes may be delayed before they hit the endpoint memory
374  *
375  * The cache hint is only a performance hint: CPUs may alias these hints.
376  * Eg, a CPU not implementing read allocate but implementing write allocate
377  * will provide a write allocate mapping instead.
378  */
379 void __iomem *ioremap(resource_size_t res_cookie, size_t size);
380 #define ioremap ioremap
381 
382 /*
383  * Do not use ioremap_cache for mapping memory. Use memremap instead.
384  */
385 void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size);
386 #define ioremap_cache ioremap_cache
387 
388 void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
389 #define ioremap_wc ioremap_wc
390 #define ioremap_wt ioremap_wc
391 
392 void iounmap(volatile void __iomem *io_addr);
393 #define iounmap iounmap
394 
395 void *arch_memremap_wb(phys_addr_t phys_addr, size_t size, unsigned long flags);
396 #define arch_memremap_wb arch_memremap_wb
397 
398 /*
399  * io{read,write}{16,32}be() macros
400  */
401 #define ioread16be(p)		({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
402 #define ioread32be(p)		({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
403 
404 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
405 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
406 
407 #ifndef ioport_map
408 #define ioport_map ioport_map
409 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
410 #endif
411 #ifndef ioport_unmap
412 #define ioport_unmap ioport_unmap
413 extern void ioport_unmap(void __iomem *addr);
414 #endif
415 
416 struct pci_dev;
417 
418 #define pci_iounmap pci_iounmap
419 extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
420 
421 #include <asm-generic/io.h>
422 
423 #ifdef CONFIG_MMU
424 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
425 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
426 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
427 extern bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
428 					unsigned long flags);
429 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
430 #endif
431 
432 /*
433  * Register ISA memory and port locations for glibc iopl/inb/outb
434  * emulation.
435  */
436 extern void register_isa_ports(unsigned int mmio, unsigned int io,
437 			       unsigned int io_shift);
438 
439 #endif	/* __KERNEL__ */
440 #endif	/* __ASM_ARM_IO_H */
441