xref: /openbmc/linux/arch/arm/include/asm/io.h (revision 113094f7)
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_page_to_bus page_to_phys
34 #define isa_bus_to_virt phys_to_virt
35 
36 /*
37  * Atomic MMIO-wide IO modify
38  */
39 extern void atomic_io_modify(void __iomem *reg, u32 mask, u32 set);
40 extern void atomic_io_modify_relaxed(void __iomem *reg, u32 mask, u32 set);
41 
42 /*
43  * Generic IO read/write.  These perform native-endian accesses.  Note
44  * that some architectures will want to re-define __raw_{read,write}w.
45  */
46 void __raw_writesb(volatile void __iomem *addr, const void *data, int bytelen);
47 void __raw_writesw(volatile void __iomem *addr, const void *data, int wordlen);
48 void __raw_writesl(volatile void __iomem *addr, const void *data, int longlen);
49 
50 void __raw_readsb(const volatile void __iomem *addr, void *data, int bytelen);
51 void __raw_readsw(const volatile void __iomem *addr, void *data, int wordlen);
52 void __raw_readsl(const volatile void __iomem *addr, void *data, int longlen);
53 
54 #if __LINUX_ARM_ARCH__ < 6
55 /*
56  * Half-word accesses are problematic with RiscPC due to limitations of
57  * the bus. Rather than special-case the machine, just let the compiler
58  * generate the access for CPUs prior to ARMv6.
59  */
60 #define __raw_readw(a)         (__chk_io_ptr(a), *(volatile unsigned short __force *)(a))
61 #define __raw_writew(v,a)      ((void)(__chk_io_ptr(a), *(volatile unsigned short __force *)(a) = (v)))
62 #else
63 /*
64  * When running under a hypervisor, we want to avoid I/O accesses with
65  * writeback addressing modes as these incur a significant performance
66  * overhead (the address generation must be emulated in software).
67  */
68 #define __raw_writew __raw_writew
69 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
70 {
71 	asm volatile("strh %1, %0"
72 		     : : "Q" (*(volatile u16 __force *)addr), "r" (val));
73 }
74 
75 #define __raw_readw __raw_readw
76 static inline u16 __raw_readw(const volatile void __iomem *addr)
77 {
78 	u16 val;
79 	asm volatile("ldrh %0, %1"
80 		     : "=r" (val)
81 		     : "Q" (*(volatile u16 __force *)addr));
82 	return val;
83 }
84 #endif
85 
86 #define __raw_writeb __raw_writeb
87 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
88 {
89 	asm volatile("strb %1, %0"
90 		     : : "Qo" (*(volatile u8 __force *)addr), "r" (val));
91 }
92 
93 #define __raw_writel __raw_writel
94 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
95 {
96 	asm volatile("str %1, %0"
97 		     : : "Qo" (*(volatile u32 __force *)addr), "r" (val));
98 }
99 
100 #define __raw_readb __raw_readb
101 static inline u8 __raw_readb(const volatile void __iomem *addr)
102 {
103 	u8 val;
104 	asm volatile("ldrb %0, %1"
105 		     : "=r" (val)
106 		     : "Qo" (*(volatile u8 __force *)addr));
107 	return val;
108 }
109 
110 #define __raw_readl __raw_readl
111 static inline u32 __raw_readl(const volatile void __iomem *addr)
112 {
113 	u32 val;
114 	asm volatile("ldr %0, %1"
115 		     : "=r" (val)
116 		     : "Qo" (*(volatile u32 __force *)addr));
117 	return val;
118 }
119 
120 /*
121  * Architecture ioremap implementation.
122  */
123 #define MT_DEVICE		0
124 #define MT_DEVICE_NONSHARED	1
125 #define MT_DEVICE_CACHED	2
126 #define MT_DEVICE_WC		3
127 /*
128  * types 4 onwards can be found in asm/mach/map.h and are undefined
129  * for ioremap
130  */
131 
132 /*
133  * __arm_ioremap takes CPU physical address.
134  * __arm_ioremap_pfn takes a Page Frame Number and an offset into that page
135  * The _caller variety takes a __builtin_return_address(0) value for
136  * /proc/vmalloc to use - and should only be used in non-inline functions.
137  */
138 extern void __iomem *__arm_ioremap_caller(phys_addr_t, size_t, unsigned int,
139 	void *);
140 extern void __iomem *__arm_ioremap_pfn(unsigned long, unsigned long, size_t, unsigned int);
141 extern void __iomem *__arm_ioremap_exec(phys_addr_t, size_t, bool cached);
142 extern void __iounmap(volatile void __iomem *addr);
143 
144 extern void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
145 	unsigned int, void *);
146 extern void (*arch_iounmap)(volatile void __iomem *);
147 
148 /*
149  * Bad read/write accesses...
150  */
151 extern void __readwrite_bug(const char *fn);
152 
153 /*
154  * A typesafe __io() helper
155  */
156 static inline void __iomem *__typesafe_io(unsigned long addr)
157 {
158 	return (void __iomem *)addr;
159 }
160 
161 #define IOMEM(x)	((void __force __iomem *)(x))
162 
163 /* IO barriers */
164 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
165 #include <asm/barrier.h>
166 #define __iormb()		rmb()
167 #define __iowmb()		wmb()
168 #else
169 #define __iormb()		do { } while (0)
170 #define __iowmb()		do { } while (0)
171 #endif
172 
173 /* PCI fixed i/o mapping */
174 #define PCI_IO_VIRT_BASE	0xfee00000
175 #define PCI_IOBASE		((void __iomem *)PCI_IO_VIRT_BASE)
176 
177 #if defined(CONFIG_PCI)
178 void pci_ioremap_set_mem_type(int mem_type);
179 #else
180 static inline void pci_ioremap_set_mem_type(int mem_type) {}
181 #endif
182 
183 extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
184 
185 /*
186  * PCI configuration space mapping function.
187  *
188  * The PCI specification does not allow configuration write
189  * transactions to be posted. Add an arch specific
190  * pci_remap_cfgspace() definition that is implemented
191  * through strongly ordered memory mappings.
192  */
193 #define pci_remap_cfgspace pci_remap_cfgspace
194 void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size);
195 /*
196  * Now, pick up the machine-defined IO definitions
197  */
198 #ifdef CONFIG_NEED_MACH_IO_H
199 #include <mach/io.h>
200 #elif defined(CONFIG_PCI)
201 #define IO_SPACE_LIMIT	((resource_size_t)0xfffff)
202 #define __io(a)		__typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
203 #else
204 #define __io(a)		__typesafe_io((a) & IO_SPACE_LIMIT)
205 #endif
206 
207 /*
208  * This is the limit of PC card/PCI/ISA IO space, which is by default
209  * 64K if we have PC card, PCI or ISA support.  Otherwise, default to
210  * zero to prevent ISA/PCI drivers claiming IO space (and potentially
211  * oopsing.)
212  *
213  * Only set this larger if you really need inb() et.al. to operate over
214  * a larger address space.  Note that SOC_COMMON ioremaps each sockets
215  * IO space area, and so inb() et.al. must be defined to operate as per
216  * readb() et.al. on such platforms.
217  */
218 #ifndef IO_SPACE_LIMIT
219 #if defined(CONFIG_PCMCIA_SOC_COMMON) || defined(CONFIG_PCMCIA_SOC_COMMON_MODULE)
220 #define IO_SPACE_LIMIT ((resource_size_t)0xffffffff)
221 #elif defined(CONFIG_PCI) || defined(CONFIG_ISA) || defined(CONFIG_PCCARD)
222 #define IO_SPACE_LIMIT ((resource_size_t)0xffff)
223 #else
224 #define IO_SPACE_LIMIT ((resource_size_t)0)
225 #endif
226 #endif
227 
228 /*
229  *  IO port access primitives
230  *  -------------------------
231  *
232  * The ARM doesn't have special IO access instructions; all IO is memory
233  * mapped.  Note that these are defined to perform little endian accesses
234  * only.  Their primary purpose is to access PCI and ISA peripherals.
235  *
236  * Note that for a big endian machine, this implies that the following
237  * big endian mode connectivity is in place, as described by numerous
238  * ARM documents:
239  *
240  *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
241  *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
242  *
243  * The machine specific io.h include defines __io to translate an "IO"
244  * address to a memory address.
245  *
246  * Note that we prevent GCC re-ordering or caching values in expressions
247  * by introducing sequence points into the in*() definitions.  Note that
248  * __raw_* do not guarantee this behaviour.
249  *
250  * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
251  */
252 #ifdef __io
253 #define outb(v,p)	({ __iowmb(); __raw_writeb(v,__io(p)); })
254 #define outw(v,p)	({ __iowmb(); __raw_writew((__force __u16) \
255 					cpu_to_le16(v),__io(p)); })
256 #define outl(v,p)	({ __iowmb(); __raw_writel((__force __u32) \
257 					cpu_to_le32(v),__io(p)); })
258 
259 #define inb(p)	({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
260 #define inw(p)	({ __u16 __v = le16_to_cpu((__force __le16) \
261 			__raw_readw(__io(p))); __iormb(); __v; })
262 #define inl(p)	({ __u32 __v = le32_to_cpu((__force __le32) \
263 			__raw_readl(__io(p))); __iormb(); __v; })
264 
265 #define outsb(p,d,l)		__raw_writesb(__io(p),d,l)
266 #define outsw(p,d,l)		__raw_writesw(__io(p),d,l)
267 #define outsl(p,d,l)		__raw_writesl(__io(p),d,l)
268 
269 #define insb(p,d,l)		__raw_readsb(__io(p),d,l)
270 #define insw(p,d,l)		__raw_readsw(__io(p),d,l)
271 #define insl(p,d,l)		__raw_readsl(__io(p),d,l)
272 #endif
273 
274 /*
275  * String version of IO memory access ops:
276  */
277 extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
278 extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
279 extern void _memset_io(volatile void __iomem *, int, size_t);
280 
281 /*
282  *  Memory access primitives
283  *  ------------------------
284  *
285  * These perform PCI memory accesses via an ioremap region.  They don't
286  * take an address as such, but a cookie.
287  *
288  * Again, these are defined to perform little endian accesses.  See the
289  * IO port primitives for more information.
290  */
291 #ifndef readl
292 #define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
293 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
294 					__raw_readw(c)); __r; })
295 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
296 					__raw_readl(c)); __r; })
297 
298 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
299 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
300 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
301 
302 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
303 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
304 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
305 
306 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
307 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
308 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
309 
310 #define readsb(p,d,l)		__raw_readsb(p,d,l)
311 #define readsw(p,d,l)		__raw_readsw(p,d,l)
312 #define readsl(p,d,l)		__raw_readsl(p,d,l)
313 
314 #define writesb(p,d,l)		__raw_writesb(p,d,l)
315 #define writesw(p,d,l)		__raw_writesw(p,d,l)
316 #define writesl(p,d,l)		__raw_writesl(p,d,l)
317 
318 #ifndef __ARMBE__
319 static inline void memset_io(volatile void __iomem *dst, unsigned c,
320 	size_t count)
321 {
322 	extern void mmioset(void *, unsigned int, size_t);
323 	mmioset((void __force *)dst, c, count);
324 }
325 #define memset_io(dst,c,count) memset_io(dst,c,count)
326 
327 static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
328 	size_t count)
329 {
330 	extern void mmiocpy(void *, const void *, size_t);
331 	mmiocpy(to, (const void __force *)from, count);
332 }
333 #define memcpy_fromio(to,from,count) memcpy_fromio(to,from,count)
334 
335 static inline void memcpy_toio(volatile void __iomem *to, const void *from,
336 	size_t count)
337 {
338 	extern void mmiocpy(void *, const void *, size_t);
339 	mmiocpy((void __force *)to, from, count);
340 }
341 #define memcpy_toio(to,from,count) memcpy_toio(to,from,count)
342 
343 #else
344 #define memset_io(c,v,l)	_memset_io(c,(v),(l))
345 #define memcpy_fromio(a,c,l)	_memcpy_fromio((a),c,(l))
346 #define memcpy_toio(c,a,l)	_memcpy_toio(c,(a),(l))
347 #endif
348 
349 #endif	/* readl */
350 
351 /*
352  * ioremap() and friends.
353  *
354  * ioremap() takes a resource address, and size.  Due to the ARM memory
355  * types, it is important to use the correct ioremap() function as each
356  * mapping has specific properties.
357  *
358  * Function		Memory type	Cacheability	Cache hint
359  * ioremap()		Device		n/a		n/a
360  * ioremap_nocache()	Device		n/a		n/a
361  * ioremap_cache()	Normal		Writeback	Read allocate
362  * ioremap_wc()		Normal		Non-cacheable	n/a
363  * ioremap_wt()		Normal		Non-cacheable	n/a
364  *
365  * All device mappings have the following properties:
366  * - no access speculation
367  * - no repetition (eg, on return from an exception)
368  * - number, order and size of accesses are maintained
369  * - unaligned accesses are "unpredictable"
370  * - writes may be delayed before they hit the endpoint device
371  *
372  * ioremap_nocache() is the same as ioremap() as there are too many device
373  * drivers using this for device registers, and documentation which tells
374  * people to use it for such for this to be any different.  This is not a
375  * safe fallback for memory-like mappings, or memory regions where the
376  * compiler may generate unaligned accesses - eg, via inlining its own
377  * memcpy.
378  *
379  * All normal memory mappings have the following properties:
380  * - reads can be repeated with no side effects
381  * - repeated reads return the last value written
382  * - reads can fetch additional locations without side effects
383  * - writes can be repeated (in certain cases) with no side effects
384  * - writes can be merged before accessing the target
385  * - unaligned accesses can be supported
386  * - ordering is not guaranteed without explicit dependencies or barrier
387  *   instructions
388  * - writes may be delayed before they hit the endpoint memory
389  *
390  * The cache hint is only a performance hint: CPUs may alias these hints.
391  * Eg, a CPU not implementing read allocate but implementing write allocate
392  * will provide a write allocate mapping instead.
393  */
394 void __iomem *ioremap(resource_size_t res_cookie, size_t size);
395 #define ioremap ioremap
396 #define ioremap_nocache ioremap
397 
398 /*
399  * Do not use ioremap_cache for mapping memory. Use memremap instead.
400  */
401 void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size);
402 #define ioremap_cache ioremap_cache
403 
404 /*
405  * Do not use ioremap_cached in new code. Provided for the benefit of
406  * the pxa2xx-flash MTD driver only.
407  */
408 void __iomem *ioremap_cached(resource_size_t res_cookie, size_t size);
409 
410 void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
411 #define ioremap_wc ioremap_wc
412 #define ioremap_wt ioremap_wc
413 
414 void iounmap(volatile void __iomem *iomem_cookie);
415 #define iounmap iounmap
416 
417 void *arch_memremap_wb(phys_addr_t phys_addr, size_t size);
418 #define arch_memremap_wb arch_memremap_wb
419 
420 /*
421  * io{read,write}{16,32}be() macros
422  */
423 #define ioread16be(p)		({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
424 #define ioread32be(p)		({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
425 
426 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
427 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
428 
429 #ifndef ioport_map
430 #define ioport_map ioport_map
431 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
432 #endif
433 #ifndef ioport_unmap
434 #define ioport_unmap ioport_unmap
435 extern void ioport_unmap(void __iomem *addr);
436 #endif
437 
438 struct pci_dev;
439 
440 #define pci_iounmap pci_iounmap
441 extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
442 
443 /*
444  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
445  * access
446  */
447 #define xlate_dev_mem_ptr(p)	__va(p)
448 
449 /*
450  * Convert a virtual cached pointer to an uncached pointer
451  */
452 #define xlate_dev_kmem_ptr(p)	p
453 
454 #include <asm-generic/io.h>
455 
456 #ifdef CONFIG_MMU
457 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
458 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
459 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
460 extern int devmem_is_allowed(unsigned long pfn);
461 #endif
462 
463 /*
464  * Register ISA memory and port locations for glibc iopl/inb/outb
465  * emulation.
466  */
467 extern void register_isa_ports(unsigned int mmio, unsigned int io,
468 			       unsigned int io_shift);
469 
470 #endif	/* __KERNEL__ */
471 #endif	/* __ASM_ARM_IO_H */
472