1 /* SPDX-License-Identifier: GPL-2.0 */
6 * This file contains the definitions for the x86 IO instructions
7 * inb/inw/inl/outb/outw/outl and the "string versions" of the same
8 * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
9 * versions of the single-IO instructions (inb_p/inw_p/..).
11 * This file is not meant to be obfuscating: it's just complicated
12 * to (a) handle it all in a way that makes gcc able to optimize it
13 * as well as possible and (b) trying to avoid writing the same thing
14 * over and over again with slight variations and possibly making a
19 * Thanks to James van Artsdalen for a better timing-fix than
20 * the two short jumps: using outb's to a nonexistent port seems
21 * to guarantee better timings even on fast machines.
23 * On the other hand, I'd like to be sure of a non-existent port:
24 * I feel a bit unsafe about using 0x80 (should be safe, though)
30 * Bit simplified and optimized by Jan Hubicka
31 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
33 * isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
34 * isa_read[wl] and isa_write[wl] fixed
35 * - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
38 #define ARCH_HAS_IOREMAP_WC
39 #define ARCH_HAS_IOREMAP_WT
41 #include <linux/string.h>
42 #include <linux/compiler.h>
44 #include <asm/early_ioremap.h>
45 #include <asm/pgtable_types.h>
47 #define build_mmio_read(name, size, type, reg, barrier) \
48 static inline type name(const volatile void __iomem *addr) \
49 { type ret; asm volatile("mov" size " %1,%0":reg (ret) \
50 :"m" (*(volatile type __force *)addr) barrier); return ret; }
52 #define build_mmio_write(name, size, type, reg, barrier) \
53 static inline void name(type val, volatile void __iomem *addr) \
54 { asm volatile("mov" size " %0,%1": :reg (val), \
55 "m" (*(volatile type __force *)addr) barrier); }
57 build_mmio_read(readb, "b", unsigned char, "=q", :"memory")
58 build_mmio_read(readw, "w", unsigned short, "=r", :"memory")
59 build_mmio_read(readl, "l", unsigned int, "=r", :"memory")
61 build_mmio_read(__readb, "b", unsigned char, "=q", )
62 build_mmio_read(__readw, "w", unsigned short, "=r", )
63 build_mmio_read(__readl, "l", unsigned int, "=r", )
65 build_mmio_write(writeb, "b", unsigned char, "q", :"memory")
66 build_mmio_write(writew, "w", unsigned short, "r", :"memory")
67 build_mmio_write(writel, "l", unsigned int, "r", :"memory")
69 build_mmio_write(__writeb, "b", unsigned char, "q", )
70 build_mmio_write(__writew, "w", unsigned short, "r", )
71 build_mmio_write(__writel, "l", unsigned int, "r", )
76 #define readb_relaxed(a) __readb(a)
77 #define readw_relaxed(a) __readw(a)
78 #define readl_relaxed(a) __readl(a)
79 #define __raw_readb __readb
80 #define __raw_readw __readw
81 #define __raw_readl __readl
86 #define writeb_relaxed(v, a) __writeb(v, a)
87 #define writew_relaxed(v, a) __writew(v, a)
88 #define writel_relaxed(v, a) __writel(v, a)
89 #define __raw_writeb __writeb
90 #define __raw_writew __writew
91 #define __raw_writel __writel
93 #define mmiowb() barrier()
97 build_mmio_read(readq, "q", unsigned long, "=r", :"memory")
98 build_mmio_read(__readq, "q", unsigned long, "=r", )
99 build_mmio_write(writeq, "q", unsigned long, "r", :"memory")
100 build_mmio_write(__writeq, "q", unsigned long, "r", )
102 #define readq_relaxed(a) __readq(a)
103 #define writeq_relaxed(v, a) __writeq(v, a)
105 #define __raw_readq __readq
106 #define __raw_writeq __writeq
108 /* Let people know that we have them */
110 #define writeq writeq
115 * virt_to_phys - map virtual addresses to physical
116 * @address: address to remap
118 * The returned physical address is the physical (CPU) mapping for
119 * the memory address given. It is only valid to use this function on
120 * addresses directly mapped or allocated via kmalloc.
122 * This function does not give bus mappings for DMA transfers. In
123 * almost all conceivable cases a device driver should not be using
127 static inline phys_addr_t virt_to_phys(volatile void *address)
129 return __pa(address);
131 #define virt_to_phys virt_to_phys
134 * phys_to_virt - map physical address to virtual
135 * @address: address to remap
137 * The returned virtual address is a current CPU mapping for
138 * the memory address given. It is only valid to use this function on
139 * addresses that have a kernel mapping
141 * This function does not handle bus mappings for DMA transfers. In
142 * almost all conceivable cases a device driver should not be using
146 static inline void *phys_to_virt(phys_addr_t address)
148 return __va(address);
150 #define phys_to_virt phys_to_virt
153 * Change "struct page" to physical address.
155 #define page_to_phys(page) ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
158 * ISA I/O bus memory addresses are 1:1 with the physical address.
159 * However, we truncate the address to unsigned int to avoid undesirable
160 * promitions in legacy drivers.
162 static inline unsigned int isa_virt_to_bus(volatile void *address)
164 return (unsigned int)virt_to_phys(address);
166 #define isa_page_to_bus(page) ((unsigned int)page_to_phys(page))
167 #define isa_bus_to_virt phys_to_virt
170 * However PCI ones are not necessarily 1:1 and therefore these interfaces
171 * are forbidden in portable PCI drivers.
173 * Allow them on x86 for legacy drivers, though.
175 #define virt_to_bus virt_to_phys
176 #define bus_to_virt phys_to_virt
179 * The default ioremap() behavior is non-cached; if you need something
180 * else, you probably want one of the following.
182 extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
183 #define ioremap_nocache ioremap_nocache
184 extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size);
185 #define ioremap_uc ioremap_uc
187 extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
188 #define ioremap_cache ioremap_cache
189 extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
190 #define ioremap_prot ioremap_prot
193 * ioremap - map bus memory into CPU space
194 * @offset: bus address of the memory
195 * @size: size of the resource to map
197 * ioremap performs a platform specific sequence of operations to
198 * make bus memory CPU accessible via the readb/readw/readl/writeb/
199 * writew/writel functions and the other mmio helpers. The returned
200 * address is not guaranteed to be usable directly as a virtual
203 * If the area you are trying to map is a PCI BAR you should have a
204 * look at pci_iomap().
206 static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
208 return ioremap_nocache(offset, size);
210 #define ioremap ioremap
212 extern void iounmap(volatile void __iomem *addr);
213 #define iounmap iounmap
215 extern void set_iounmap_nonlazy(void);
219 #include <asm-generic/iomap.h>
222 * ISA space is 'always mapped' on a typical x86 system, no need to
223 * explicitly ioremap() it. The fact that the ISA IO space is mapped
224 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
225 * are physical addresses. The following constant pointer can be
226 * used as the IO-area pointer (it can be iounmapped as well, so the
227 * analogy with PCI is quite large):
229 #define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))
234 * This needed for two cases
235 * 1. Out of order aware processors
236 * 2. Accidentally out of order processors (PPro errata #51)
239 static inline void flush_write_buffers(void)
241 #if defined(CONFIG_X86_PPRO_FENCE)
242 asm volatile("lock; addl $0,0(%%esp)": : :"memory");
246 #endif /* __KERNEL__ */
248 extern void native_io_delay(void);
250 extern int io_delay_type;
251 extern void io_delay_init(void);
253 #if defined(CONFIG_PARAVIRT)
254 #include <asm/paravirt.h>
257 static inline void slow_down_io(void)
260 #ifdef REALLY_SLOW_IO
269 #define BUILDIO(bwl, bw, type) \
270 static inline void out##bwl(unsigned type value, int port) \
272 asm volatile("out" #bwl " %" #bw "0, %w1" \
273 : : "a"(value), "Nd"(port)); \
276 static inline unsigned type in##bwl(int port) \
278 unsigned type value; \
279 asm volatile("in" #bwl " %w1, %" #bw "0" \
280 : "=a"(value) : "Nd"(port)); \
284 static inline void out##bwl##_p(unsigned type value, int port) \
286 out##bwl(value, port); \
290 static inline unsigned type in##bwl##_p(int port) \
292 unsigned type value = in##bwl(port); \
297 static inline void outs##bwl(int port, const void *addr, unsigned long count) \
299 asm volatile("rep; outs" #bwl \
300 : "+S"(addr), "+c"(count) : "d"(port) : "memory"); \
303 static inline void ins##bwl(int port, void *addr, unsigned long count) \
305 asm volatile("rep; ins" #bwl \
306 : "+D"(addr), "+c"(count) : "d"(port) : "memory"); \
326 #define outb_p outb_p
327 #define outw_p outw_p
328 #define outl_p outl_p
333 extern void *xlate_dev_mem_ptr(phys_addr_t phys);
334 extern void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
336 #define xlate_dev_mem_ptr xlate_dev_mem_ptr
337 #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
339 extern int ioremap_change_attr(unsigned long vaddr, unsigned long size,
340 enum page_cache_mode pcm);
341 extern void __iomem *ioremap_wc(resource_size_t offset, unsigned long size);
342 #define ioremap_wc ioremap_wc
343 extern void __iomem *ioremap_wt(resource_size_t offset, unsigned long size);
344 #define ioremap_wt ioremap_wt
346 extern bool is_early_ioremap_ptep(pte_t *ptep);
352 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
353 const struct bio_vec *vec2);
355 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
356 (__BIOVEC_PHYS_MERGEABLE(vec1, vec2) && \
357 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
358 #endif /* CONFIG_XEN */
360 #define IO_SPACE_LIMIT 0xffff
362 #include <asm-generic/io.h>
366 extern int __must_check arch_phys_wc_index(int handle);
367 #define arch_phys_wc_index arch_phys_wc_index
369 extern int __must_check arch_phys_wc_add(unsigned long base,
371 extern void arch_phys_wc_del(int handle);
372 #define arch_phys_wc_add arch_phys_wc_add
375 #ifdef CONFIG_X86_PAT
376 extern int arch_io_reserve_memtype_wc(resource_size_t start, resource_size_t size);
377 extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size);
378 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
381 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
383 unsigned long flags);
384 #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap
386 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
389 #endif /* _ASM_X86_IO_H */