xref: /openbmc/linux/arch/arm/include/asm/io.h (revision 7d545e77)
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/memory.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_readw(a)         (__chk_io_ptr(a), *(volatile unsigned short __force *)(a))
60 #define __raw_writew(v,a)      ((void)(__chk_io_ptr(a), *(volatile unsigned short __force *)(a) = (v)))
61 #else
62 /*
63  * When running under a hypervisor, we want to avoid I/O accesses with
64  * writeback addressing modes as these incur a significant performance
65  * overhead (the address generation must be emulated in software).
66  */
67 #define __raw_writew __raw_writew
68 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
69 {
70 	asm volatile("strh %1, %0"
71 		     : : "Q" (*(volatile u16 __force *)addr), "r" (val));
72 }
73 
74 #define __raw_readw __raw_readw
75 static inline u16 __raw_readw(const volatile void __iomem *addr)
76 {
77 	u16 val;
78 	asm volatile("ldrh %0, %1"
79 		     : "=r" (val)
80 		     : "Q" (*(volatile u16 __force *)addr));
81 	return val;
82 }
83 #endif
84 
85 #define __raw_writeb __raw_writeb
86 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
87 {
88 	asm volatile("strb %1, %0"
89 		     : : "Qo" (*(volatile u8 __force *)addr), "r" (val));
90 }
91 
92 #define __raw_writel __raw_writel
93 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
94 {
95 	asm volatile("str %1, %0"
96 		     : : "Qo" (*(volatile u32 __force *)addr), "r" (val));
97 }
98 
99 #define __raw_readb __raw_readb
100 static inline u8 __raw_readb(const volatile void __iomem *addr)
101 {
102 	u8 val;
103 	asm volatile("ldrb %0, %1"
104 		     : "=r" (val)
105 		     : "Qo" (*(volatile u8 __force *)addr));
106 	return val;
107 }
108 
109 #define __raw_readl __raw_readl
110 static inline u32 __raw_readl(const volatile void __iomem *addr)
111 {
112 	u32 val;
113 	asm volatile("ldr %0, %1"
114 		     : "=r" (val)
115 		     : "Qo" (*(volatile u32 __force *)addr));
116 	return val;
117 }
118 
119 /*
120  * Architecture ioremap implementation.
121  */
122 #define MT_DEVICE		0
123 #define MT_DEVICE_NONSHARED	1
124 #define MT_DEVICE_CACHED	2
125 #define MT_DEVICE_WC		3
126 /*
127  * types 4 onwards can be found in asm/mach/map.h and are undefined
128  * for ioremap
129  */
130 
131 /*
132  * __arm_ioremap takes CPU physical address.
133  * __arm_ioremap_pfn takes a Page Frame Number and an offset into that page
134  * The _caller variety takes a __builtin_return_address(0) value for
135  * /proc/vmalloc to use - and should only be used in non-inline functions.
136  */
137 extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
138 	void *);
139 extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
140 extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
141 extern void __iounmap(volatile void __iomem *addr);
142 
143 extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
144 	unsigned int, void *);
145 extern void (*arch_iounmap)(volatile void __iomem *);
146 
147 /*
148  * Bad read/write accesses...
149  */
150 extern void __readwrite_bug(const char *fn);
151 
152 /*
153  * A typesafe __io() helper
154  */
155 static inline void __iomem *__typesafe_io(unsigned long addr)
156 {
157 	return (void __iomem *)addr;
158 }
159 
160 #define IOMEM(x)	((void __force __iomem *)(x))
161 
162 /* IO barriers */
163 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
164 #include <asm/barrier.h>
165 #define __iormb()		rmb()
166 #define __iowmb()		wmb()
167 #else
168 #define __iormb()		do { } while (0)
169 #define __iowmb()		do { } while (0)
170 #endif
171 
172 /* PCI fixed i/o mapping */
173 #define PCI_IO_VIRT_BASE	0xfee00000
174 #define PCI_IOBASE		((void __iomem *)PCI_IO_VIRT_BASE)
175 
176 #if defined(CONFIG_PCI)
177 void pci_ioremap_set_mem_type(int mem_type);
178 #else
179 static inline void pci_ioremap_set_mem_type(int mem_type) {}
180 #endif
181 
182 extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
183 
184 /*
185  * PCI configuration space mapping function.
186  *
187  * The PCI specification does not allow configuration write
188  * transactions to be posted. Add an arch specific
189  * pci_remap_cfgspace() definition that is implemented
190  * through strongly ordered memory mappings.
191  */
192 #define pci_remap_cfgspace pci_remap_cfgspace
193 void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size);
194 /*
195  * Now, pick up the machine-defined IO definitions
196  */
197 #ifdef CONFIG_NEED_MACH_IO_H
198 #include <mach/io.h>
199 #elif defined(CONFIG_PCI)
200 #define IO_SPACE_LIMIT	((resource_size_t)0xfffff)
201 #define __io(a)		__typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
202 #else
203 #define __io(a)		__typesafe_io((a) & IO_SPACE_LIMIT)
204 #endif
205 
206 /*
207  * This is the limit of PC card/PCI/ISA IO space, which is by default
208  * 64K if we have PC card, PCI or ISA support.  Otherwise, default to
209  * zero to prevent ISA/PCI drivers claiming IO space (and potentially
210  * oopsing.)
211  *
212  * Only set this larger if you really need inb() et.al. to operate over
213  * a larger address space.  Note that SOC_COMMON ioremaps each sockets
214  * IO space area, and so inb() et.al. must be defined to operate as per
215  * readb() et.al. on such platforms.
216  */
217 #ifndef IO_SPACE_LIMIT
218 #if defined(CONFIG_PCMCIA_SOC_COMMON) || defined(CONFIG_PCMCIA_SOC_COMMON_MODULE)
219 #define IO_SPACE_LIMIT ((resource_size_t)0xffffffff)
220 #elif defined(CONFIG_PCI) || defined(CONFIG_ISA) || defined(CONFIG_PCCARD)
221 #define IO_SPACE_LIMIT ((resource_size_t)0xffff)
222 #else
223 #define IO_SPACE_LIMIT ((resource_size_t)0)
224 #endif
225 #endif
226 
227 /*
228  *  IO port access primitives
229  *  -------------------------
230  *
231  * The ARM doesn't have special IO access instructions; all IO is memory
232  * mapped.  Note that these are defined to perform little endian accesses
233  * only.  Their primary purpose is to access PCI and ISA peripherals.
234  *
235  * Note that for a big endian machine, this implies that the following
236  * big endian mode connectivity is in place, as described by numerous
237  * ARM documents:
238  *
239  *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
240  *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
241  *
242  * The machine specific io.h include defines __io to translate an "IO"
243  * address to a memory address.
244  *
245  * Note that we prevent GCC re-ordering or caching values in expressions
246  * by introducing sequence points into the in*() definitions.  Note that
247  * __raw_* do not guarantee this behaviour.
248  *
249  * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
250  */
251 #ifdef __io
252 #define outb(v,p)	({ __iowmb(); __raw_writeb(v,__io(p)); })
253 #define outw(v,p)	({ __iowmb(); __raw_writew((__force __u16) \
254 					cpu_to_le16(v),__io(p)); })
255 #define outl(v,p)	({ __iowmb(); __raw_writel((__force __u32) \
256 					cpu_to_le32(v),__io(p)); })
257 
258 #define inb(p)	({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
259 #define inw(p)	({ __u16 __v = le16_to_cpu((__force __le16) \
260 			__raw_readw(__io(p))); __iormb(); __v; })
261 #define inl(p)	({ __u32 __v = le32_to_cpu((__force __le32) \
262 			__raw_readl(__io(p))); __iormb(); __v; })
263 
264 #define outsb(p,d,l)		__raw_writesb(__io(p),d,l)
265 #define outsw(p,d,l)		__raw_writesw(__io(p),d,l)
266 #define outsl(p,d,l)		__raw_writesl(__io(p),d,l)
267 
268 #define insb(p,d,l)		__raw_readsb(__io(p),d,l)
269 #define insw(p,d,l)		__raw_readsw(__io(p),d,l)
270 #define insl(p,d,l)		__raw_readsl(__io(p),d,l)
271 #endif
272 
273 /*
274  * String version of IO memory access ops:
275  */
276 extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
277 extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
278 extern void _memset_io(volatile void __iomem *, int, size_t);
279 
280 /*
281  *  Memory access primitives
282  *  ------------------------
283  *
284  * These perform PCI memory accesses via an ioremap region.  They don't
285  * take an address as such, but a cookie.
286  *
287  * Again, these are defined to perform little endian accesses.  See the
288  * IO port primitives for more information.
289  */
290 #ifndef readl
291 #define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
292 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
293 					__raw_readw(c)); __r; })
294 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
295 					__raw_readl(c)); __r; })
296 
297 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
298 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
299 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
300 
301 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
302 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
303 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
304 
305 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
306 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
307 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
308 
309 #define readsb(p,d,l)		__raw_readsb(p,d,l)
310 #define readsw(p,d,l)		__raw_readsw(p,d,l)
311 #define readsl(p,d,l)		__raw_readsl(p,d,l)
312 
313 #define writesb(p,d,l)		__raw_writesb(p,d,l)
314 #define writesw(p,d,l)		__raw_writesw(p,d,l)
315 #define writesl(p,d,l)		__raw_writesl(p,d,l)
316 
317 #ifndef __ARMBE__
318 static inline void memset_io(volatile void __iomem *dst, unsigned c,
319 	size_t count)
320 {
321 	extern void mmioset(void *, unsigned int, size_t);
322 	mmioset((void __force *)dst, c, count);
323 }
324 #define memset_io(dst,c,count) memset_io(dst,c,count)
325 
326 static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
327 	size_t count)
328 {
329 	extern void mmiocpy(void *, const void *, size_t);
330 	mmiocpy(to, (const void __force *)from, count);
331 }
332 #define memcpy_fromio(to,from,count) memcpy_fromio(to,from,count)
333 
334 static inline void memcpy_toio(volatile void __iomem *to, const void *from,
335 	size_t count)
336 {
337 	extern void mmiocpy(void *, const void *, size_t);
338 	mmiocpy((void __force *)to, from, count);
339 }
340 #define memcpy_toio(to,from,count) memcpy_toio(to,from,count)
341 
342 #else
343 #define memset_io(c,v,l)	_memset_io(c,(v),(l))
344 #define memcpy_fromio(a,c,l)	_memcpy_fromio((a),c,(l))
345 #define memcpy_toio(c,a,l)	_memcpy_toio(c,(a),(l))
346 #endif
347 
348 #endif	/* readl */
349 
350 /*
351  * ioremap() and friends.
352  *
353  * ioremap() takes a resource address, and size.  Due to the ARM memory
354  * types, it is important to use the correct ioremap() function as each
355  * mapping has specific properties.
356  *
357  * Function		Memory type	Cacheability	Cache hint
358  * ioremap()		Device		n/a		n/a
359  * ioremap_nocache()	Device		n/a		n/a
360  * ioremap_cache()	Normal		Writeback	Read allocate
361  * ioremap_wc()		Normal		Non-cacheable	n/a
362  * ioremap_wt()		Normal		Non-cacheable	n/a
363  *
364  * All device mappings have the following properties:
365  * - no access speculation
366  * - no repetition (eg, on return from an exception)
367  * - number, order and size of accesses are maintained
368  * - unaligned accesses are "unpredictable"
369  * - writes may be delayed before they hit the endpoint device
370  *
371  * ioremap_nocache() is the same as ioremap() as there are too many device
372  * drivers using this for device registers, and documentation which tells
373  * people to use it for such for this to be any different.  This is not a
374  * safe fallback for memory-like mappings, or memory regions where the
375  * compiler may generate unaligned accesses - eg, via inlining its own
376  * memcpy.
377  *
378  * All normal memory mappings have the following properties:
379  * - reads can be repeated with no side effects
380  * - repeated reads return the last value written
381  * - reads can fetch additional locations without side effects
382  * - writes can be repeated (in certain cases) with no side effects
383  * - writes can be merged before accessing the target
384  * - unaligned accesses can be supported
385  * - ordering is not guaranteed without explicit dependencies or barrier
386  *   instructions
387  * - writes may be delayed before they hit the endpoint memory
388  *
389  * The cache hint is only a performance hint: CPUs may alias these hints.
390  * Eg, a CPU not implementing read allocate but implementing write allocate
391  * will provide a write allocate mapping instead.
392  */
393 void __iomem *ioremap(resource_size_t res_cookie, size_t size);
394 #define ioremap ioremap
395 #define ioremap_nocache ioremap
396 
397 /*
398  * Do not use ioremap_cache for mapping memory. Use memremap instead.
399  */
400 void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size);
401 #define ioremap_cache ioremap_cache
402 
403 /*
404  * Do not use ioremap_cached in new code. Provided for the benefit of
405  * the pxa2xx-flash MTD driver only.
406  */
407 void __iomem *ioremap_cached(resource_size_t res_cookie, size_t size);
408 
409 void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
410 #define ioremap_wc ioremap_wc
411 #define ioremap_wt ioremap_wc
412 
413 void iounmap(volatile void __iomem *iomem_cookie);
414 #define iounmap iounmap
415 
416 void *arch_memremap_wb(phys_addr_t phys_addr, size_t size);
417 #define arch_memremap_wb arch_memremap_wb
418 
419 /*
420  * io{read,write}{16,32}be() macros
421  */
422 #define ioread16be(p)		({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
423 #define ioread32be(p)		({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
424 
425 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
426 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
427 
428 #ifndef ioport_map
429 #define ioport_map ioport_map
430 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
431 #endif
432 #ifndef ioport_unmap
433 #define ioport_unmap ioport_unmap
434 extern void ioport_unmap(void __iomem *addr);
435 #endif
436 
437 struct pci_dev;
438 
439 #define pci_iounmap pci_iounmap
440 extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
441 
442 /*
443  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
444  * access
445  */
446 #define xlate_dev_mem_ptr(p)	__va(p)
447 
448 /*
449  * Convert a virtual cached pointer to an uncached pointer
450  */
451 #define xlate_dev_kmem_ptr(p)	p
452 
453 #include <asm-generic/io.h>
454 
455 #ifdef CONFIG_MMU
456 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
457 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
458 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
459 extern int devmem_is_allowed(unsigned long pfn);
460 #endif
461 
462 /*
463  * Register ISA memory and port locations for glibc iopl/inb/outb
464  * emulation.
465  */
466 extern void register_isa_ports(unsigned int mmio, unsigned int io,
467 			       unsigned int io_shift);
468 
469 #endif	/* __KERNEL__ */
470 #endif	/* __ASM_ARM_IO_H */
471