xref: /openbmc/linux/arch/arm/include/asm/io.h (revision da1d9caf)
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 void __arm_iomem_set_ro(void __iomem *ptr, size_t size);
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) || IS_ENABLED(CONFIG_PCMCIA)
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 struct resource;
184 
185 #define pci_remap_iospace pci_remap_iospace
186 int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
187 
188 /*
189  * PCI configuration space mapping function.
190  *
191  * The PCI specification does not allow configuration write
192  * transactions to be posted. Add an arch specific
193  * pci_remap_cfgspace() definition that is implemented
194  * through strongly ordered memory mappings.
195  */
196 #define pci_remap_cfgspace pci_remap_cfgspace
197 void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size);
198 /*
199  * Now, pick up the machine-defined IO definitions
200  */
201 #ifdef CONFIG_NEED_MACH_IO_H
202 #include <mach/io.h>
203 #else
204 #if IS_ENABLED(CONFIG_PCMCIA) || defined(CONFIG_PCI)
205 #define IO_SPACE_LIMIT	((resource_size_t)0xfffff)
206 #else
207 #define IO_SPACE_LIMIT ((resource_size_t)0)
208 #endif
209 #define __io(a)		__typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
210 #endif
211 
212 /*
213  *  IO port access primitives
214  *  -------------------------
215  *
216  * The ARM doesn't have special IO access instructions; all IO is memory
217  * mapped.  Note that these are defined to perform little endian accesses
218  * only.  Their primary purpose is to access PCI and ISA peripherals.
219  *
220  * Note that for a big endian machine, this implies that the following
221  * big endian mode connectivity is in place, as described by numerous
222  * ARM documents:
223  *
224  *    PCI:  D0-D7   D8-D15 D16-D23 D24-D31
225  *    ARM: D24-D31 D16-D23  D8-D15  D0-D7
226  *
227  * The machine specific io.h include defines __io to translate an "IO"
228  * address to a memory address.
229  *
230  * Note that we prevent GCC re-ordering or caching values in expressions
231  * by introducing sequence points into the in*() definitions.  Note that
232  * __raw_* do not guarantee this behaviour.
233  *
234  * The {in,out}[bwl] macros are for emulating x86-style PCI/ISA IO space.
235  */
236 #ifdef __io
237 #define outb(v,p)	({ __iowmb(); __raw_writeb(v,__io(p)); })
238 #define outw(v,p)	({ __iowmb(); __raw_writew((__force __u16) \
239 					cpu_to_le16(v),__io(p)); })
240 #define outl(v,p)	({ __iowmb(); __raw_writel((__force __u32) \
241 					cpu_to_le32(v),__io(p)); })
242 
243 #define inb(p)	({ __u8 __v = __raw_readb(__io(p)); __iormb(); __v; })
244 #define inw(p)	({ __u16 __v = le16_to_cpu((__force __le16) \
245 			__raw_readw(__io(p))); __iormb(); __v; })
246 #define inl(p)	({ __u32 __v = le32_to_cpu((__force __le32) \
247 			__raw_readl(__io(p))); __iormb(); __v; })
248 
249 #define outsb(p,d,l)		__raw_writesb(__io(p),d,l)
250 #define outsw(p,d,l)		__raw_writesw(__io(p),d,l)
251 #define outsl(p,d,l)		__raw_writesl(__io(p),d,l)
252 
253 #define insb(p,d,l)		__raw_readsb(__io(p),d,l)
254 #define insw(p,d,l)		__raw_readsw(__io(p),d,l)
255 #define insl(p,d,l)		__raw_readsl(__io(p),d,l)
256 #endif
257 
258 /*
259  * String version of IO memory access ops:
260  */
261 extern void _memcpy_fromio(void *, const volatile void __iomem *, size_t);
262 extern void _memcpy_toio(volatile void __iomem *, const void *, size_t);
263 extern void _memset_io(volatile void __iomem *, int, size_t);
264 
265 /*
266  *  Memory access primitives
267  *  ------------------------
268  *
269  * These perform PCI memory accesses via an ioremap region.  They don't
270  * take an address as such, but a cookie.
271  *
272  * Again, these are defined to perform little endian accesses.  See the
273  * IO port primitives for more information.
274  */
275 #ifndef readl
276 #define readb_relaxed(c) ({ u8  __r = __raw_readb(c); __r; })
277 #define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16) \
278 					__raw_readw(c)); __r; })
279 #define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32) \
280 					__raw_readl(c)); __r; })
281 
282 #define writeb_relaxed(v,c)	__raw_writeb(v,c)
283 #define writew_relaxed(v,c)	__raw_writew((__force u16) cpu_to_le16(v),c)
284 #define writel_relaxed(v,c)	__raw_writel((__force u32) cpu_to_le32(v),c)
285 
286 #define readb(c)		({ u8  __v = readb_relaxed(c); __iormb(); __v; })
287 #define readw(c)		({ u16 __v = readw_relaxed(c); __iormb(); __v; })
288 #define readl(c)		({ u32 __v = readl_relaxed(c); __iormb(); __v; })
289 
290 #define writeb(v,c)		({ __iowmb(); writeb_relaxed(v,c); })
291 #define writew(v,c)		({ __iowmb(); writew_relaxed(v,c); })
292 #define writel(v,c)		({ __iowmb(); writel_relaxed(v,c); })
293 
294 #define readsb(p,d,l)		__raw_readsb(p,d,l)
295 #define readsw(p,d,l)		__raw_readsw(p,d,l)
296 #define readsl(p,d,l)		__raw_readsl(p,d,l)
297 
298 #define writesb(p,d,l)		__raw_writesb(p,d,l)
299 #define writesw(p,d,l)		__raw_writesw(p,d,l)
300 #define writesl(p,d,l)		__raw_writesl(p,d,l)
301 
302 #ifndef __ARMBE__
303 static inline void memset_io(volatile void __iomem *dst, unsigned c,
304 	size_t count)
305 {
306 	extern void mmioset(void *, unsigned int, size_t);
307 	mmioset((void __force *)dst, c, count);
308 }
309 #define memset_io(dst,c,count) memset_io(dst,c,count)
310 
311 static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
312 	size_t count)
313 {
314 	extern void mmiocpy(void *, const void *, size_t);
315 	mmiocpy(to, (const void __force *)from, count);
316 }
317 #define memcpy_fromio(to,from,count) memcpy_fromio(to,from,count)
318 
319 static inline void memcpy_toio(volatile void __iomem *to, const void *from,
320 	size_t count)
321 {
322 	extern void mmiocpy(void *, const void *, size_t);
323 	mmiocpy((void __force *)to, from, count);
324 }
325 #define memcpy_toio(to,from,count) memcpy_toio(to,from,count)
326 
327 #else
328 #define memset_io(c,v,l)	_memset_io(c,(v),(l))
329 #define memcpy_fromio(a,c,l)	_memcpy_fromio((a),c,(l))
330 #define memcpy_toio(c,a,l)	_memcpy_toio(c,(a),(l))
331 #endif
332 
333 #endif	/* readl */
334 
335 /*
336  * ioremap() and friends.
337  *
338  * ioremap() takes a resource address, and size.  Due to the ARM memory
339  * types, it is important to use the correct ioremap() function as each
340  * mapping has specific properties.
341  *
342  * Function		Memory type	Cacheability	Cache hint
343  * ioremap()		Device		n/a		n/a
344  * ioremap_cache()	Normal		Writeback	Read allocate
345  * ioremap_wc()		Normal		Non-cacheable	n/a
346  * ioremap_wt()		Normal		Non-cacheable	n/a
347  *
348  * All device mappings have the following properties:
349  * - no access speculation
350  * - no repetition (eg, on return from an exception)
351  * - number, order and size of accesses are maintained
352  * - unaligned accesses are "unpredictable"
353  * - writes may be delayed before they hit the endpoint device
354  *
355  * All normal memory mappings have the following properties:
356  * - reads can be repeated with no side effects
357  * - repeated reads return the last value written
358  * - reads can fetch additional locations without side effects
359  * - writes can be repeated (in certain cases) with no side effects
360  * - writes can be merged before accessing the target
361  * - unaligned accesses can be supported
362  * - ordering is not guaranteed without explicit dependencies or barrier
363  *   instructions
364  * - writes may be delayed before they hit the endpoint memory
365  *
366  * The cache hint is only a performance hint: CPUs may alias these hints.
367  * Eg, a CPU not implementing read allocate but implementing write allocate
368  * will provide a write allocate mapping instead.
369  */
370 void __iomem *ioremap(resource_size_t res_cookie, size_t size);
371 #define ioremap ioremap
372 
373 /*
374  * Do not use ioremap_cache for mapping memory. Use memremap instead.
375  */
376 void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size);
377 #define ioremap_cache ioremap_cache
378 
379 void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size);
380 #define ioremap_wc ioremap_wc
381 #define ioremap_wt ioremap_wc
382 
383 void iounmap(volatile void __iomem *iomem_cookie);
384 #define iounmap iounmap
385 
386 void *arch_memremap_wb(phys_addr_t phys_addr, size_t size);
387 #define arch_memremap_wb arch_memremap_wb
388 
389 /*
390  * io{read,write}{16,32}be() macros
391  */
392 #define ioread16be(p)		({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(); __v; })
393 #define ioread32be(p)		({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(); __v; })
394 
395 #define iowrite16be(v,p)	({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
396 #define iowrite32be(v,p)	({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
397 
398 #ifndef ioport_map
399 #define ioport_map ioport_map
400 extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
401 #endif
402 #ifndef ioport_unmap
403 #define ioport_unmap ioport_unmap
404 extern void ioport_unmap(void __iomem *addr);
405 #endif
406 
407 struct pci_dev;
408 
409 #define pci_iounmap pci_iounmap
410 extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
411 
412 /*
413  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
414  * access
415  */
416 #define xlate_dev_mem_ptr(p)	__va(p)
417 
418 #include <asm-generic/io.h>
419 
420 #ifdef CONFIG_MMU
421 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
422 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
423 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
424 extern bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
425 					unsigned long flags);
426 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
427 #endif
428 
429 /*
430  * Register ISA memory and port locations for glibc iopl/inb/outb
431  * emulation.
432  */
433 extern void register_isa_ports(unsigned int mmio, unsigned int io,
434 			       unsigned int io_shift);
435 
436 #endif	/* __KERNEL__ */
437 #endif	/* __ASM_ARM_IO_H */
438