linux/include/asm-x86/io_64.h

#ifndef _ASM_IO_H
#define _ASM_IO_H


/*
 * This file contains the definitions for the x86 IO instructions
 * inb/inw/inl/outb/outw/outl and the "string versions" of the same
 * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
 * versions of the single-IO instructions (inb_p/inw_p/..).
 *
 * This file is not meant to be obfuscating: it's just complicated
 * to (a) handle it all in a way that makes gcc able to optimize it
 * as well as possible and (b) trying to avoid writing the same thing
 * over and over again with slight variations and possibly making a
 * mistake somewhere.
 */

/*
 * Thanks to James van Artsdalen for a better timing-fix than
 * the two short jumps: using outb's to a nonexistent port seems
 * to guarantee better timings even on fast machines.
 *
 * On the other hand, I'd like to be sure of a non-existent port:
 * I feel a bit unsafe about using 0x80 (should be safe, though)
 *
 *		Linus
 */

 /*
  *  Bit simplified and optimized by Jan Hubicka
  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999.
  *
  *  isa_memset_io, isa_memcpy_fromio, isa_memcpy_toio added,
  *  isa_read[wl] and isa_write[wl] fixed
  *  - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  */

extern void native_io_delay(void);

extern int io_delay_type;
extern void io_delay_init(void);

#if defined(CONFIG_PARAVIRT)
#include <asm/paravirt.h>
#else

static inline void slow_down_io(void)
{
	native_io_delay();
#ifdef REALLY_SLOW_IO
	native_io_delay();
	native_io_delay();
	native_io_delay();
#endif
}
#endif

/*
 * Talk about misusing macros..
 */
#define __OUT1(s, x)							\
static inline void out##s(unsigned x value, unsigned short port) {

#define __OUT2(s, s1, s2)				\
asm volatile ("out" #s " %" s1 "0,%" s2 "1"

#ifndef REALLY_SLOW_IO
#define REALLY_SLOW_IO
#define UNSET_REALLY_SLOW_IO
#endif

#define __OUT(s, s1, x)							\
	__OUT1(s, x) __OUT2(s, s1, "w") : : "a" (value), "Nd" (port));	\
	}								\
	__OUT1(s##_p, x) __OUT2(s, s1, "w") : : "a" (value), "Nd" (port)); \
	slow_down_io();							\
}

#define __IN1(s)							\
static inline RETURN_TYPE in##s(unsigned short port)			\
{									\
	RETURN_TYPE _v;

#define __IN2(s, s1, s2)						\
	asm volatile ("in" #s " %" s2 "1,%" s1 "0"

#define __IN(s, s1, i...)						\
	__IN1(s) __IN2(s, s1, "w") : "=a" (_v) : "Nd" (port), ##i);	\
	return _v;							\
	}								\
	__IN1(s##_p) __IN2(s, s1, "w") : "=a" (_v) : "Nd" (port), ##i);	\
	slow_down_io(); \
	return _v; }

#ifdef UNSET_REALLY_SLOW_IO
#undef REALLY_SLOW_IO
#endif

#define __INS(s)							\
static inline void ins##s(unsigned short port, void *addr,		\
			  unsigned long count)				\
{									\
	asm volatile ("rep ; ins" #s					\
		      : "=D" (addr), "=c" (count)			\
		      : "d" (port), "0" (addr), "1" (count));		\
}

#define __OUTS(s)							\
static inline void outs##s(unsigned short port, const void *addr,	\
			   unsigned long count)				\
{									\
	asm volatile ("rep ; outs" #s					\
		      : "=S" (addr), "=c" (count)			\
		      : "d" (port), "0" (addr), "1" (count));		\
}

#define RETURN_TYPE unsigned char
__IN(b, "")
#undef RETURN_TYPE
#define RETURN_TYPE unsigned short
__IN(w, "")
#undef RETURN_TYPE
#define RETURN_TYPE unsigned int
__IN(l, "")
#undef RETURN_TYPE

__OUT(b, "b", char)
__OUT(w, "w", short)
__OUT(l, , int)

__INS(b)
__INS(w)
__INS(l)

__OUTS(b)
__OUTS(w)
__OUTS(l)

#define IO_SPACE_LIMIT 0xffff

#if defined(__KERNEL__) && defined(__x86_64__)

#include <linux/vmalloc.h>

#ifndef __i386__
/*
 * Change virtual addresses to physical addresses and vv.
 * These are pretty trivial
 */
static inline unsigned long virt_to_phys(volatile void *address)
{
	return __pa(address);
}

static inline void *phys_to_virt(unsigned long address)
{
	return __va(address);
}
#endif

/*
 * Change "struct page" to physical address.
 */
#define page_to_phys(page)    ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)

#include <asm-generic/iomap.h>

extern void *early_ioremap(unsigned long addr, unsigned long size);
extern void early_iounmap(void *addr, unsigned long size);

/*
 * This one maps high address device memory and turns off caching for that area.
 * it's useful if some control registers are in such an area and write combining
 * or read caching is not desirable:
 */
extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size);
extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);

/*
 * The default ioremap() behavior is non-cached:
 */
static inline void __iomem *ioremap(resource_size_t offset, unsigned long size)
{
	return ioremap_nocache(offset, size);
}

extern void iounmap(volatile void __iomem *addr);

extern void __iomem *fix_ioremap(unsigned idx, unsigned long phys);

/*
 * ISA I/O bus memory addresses are 1:1 with the physical address.
 */
#define isa_virt_to_bus virt_to_phys
#define isa_page_to_bus page_to_phys
#define isa_bus_to_virt phys_to_virt

/*
 * However PCI ones are not necessarily 1:1 and therefore these interfaces
 * are forbidden in portable PCI drivers.
 *
 * Allow them on x86 for legacy drivers, though.
 */
#define virt_to_bus virt_to_phys
#define bus_to_virt phys_to_virt

/*
 * readX/writeX() are used to access memory mapped devices. On some
 * architectures the memory mapped IO stuff needs to be accessed
 * differently. On the x86 architecture, we just read/write the
 * memory location directly.
 */

static inline __u8 __readb(const volatile void __iomem *addr)
{
	return *(__force volatile __u8 *)addr;
}

static inline __u16 __readw(const volatile void __iomem *addr)
{
	return *(__force volatile __u16 *)addr;
}

static __always_inline __u32 __readl(const volatile void __iomem *addr)
{
	return *(__force volatile __u32 *)addr;
}

static inline __u64 __readq(const volatile void __iomem *addr)
{
	return *(__force volatile __u64 *)addr;
}

#define readb(x) __readb(x)
#define readw(x) __readw(x)
#define readl(x) __readl(x)
#define readq(x) __readq(x)
#define readb_relaxed(a) readb(a)
#define readw_relaxed(a) readw(a)
#define readl_relaxed(a) readl(a)
#define readq_relaxed(a) readq(a)
#define __raw_readb readb
#define __raw_readw readw
#define __raw_readl readl
#define __raw_readq readq

#define mmiowb()

static inline void __writel(__u32 b, volatile void __iomem *addr)
{
	*(__force volatile __u32 *)addr = b;
}

static inline void __writeq(__u64 b, volatile void __iomem *addr)
{
	*(__force volatile __u64 *)addr = b;
}

static inline void __writeb(__u8 b, volatile void __iomem *addr)
{
	*(__force volatile __u8 *)addr = b;
}

static inline void __writew(__u16 b, volatile void __iomem *addr)
{
	*(__force volatile __u16 *)addr = b;
}

#define writeq(val, addr) __writeq((val), (addr))
#define writel(val, addr) __writel((val), (addr))
#define writew(val, addr) __writew((val), (addr))
#define writeb(val, addr) __writeb((val), (addr))
#define __raw_writeb writeb
#define __raw_writew writew
#define __raw_writel writel
#define __raw_writeq writeq

void __memcpy_fromio(void *, unsigned long, unsigned);
void __memcpy_toio(unsigned long, const void *, unsigned);

static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
				 unsigned len)
{
	__memcpy_fromio(to, (unsigned long)from, len);
}

static inline void memcpy_toio(volatile void __iomem *to, const void *from,
			       unsigned len)
{
	__memcpy_toio((unsigned long)to, from, len);
}

void memset_io(volatile void __iomem *a, int b, size_t c);

/*
 * ISA space is 'always mapped' on a typical x86 system, no need to
 * explicitly ioremap() it. The fact that the ISA IO space is mapped
 * to PAGE_OFFSET is pure coincidence - it does not mean ISA values
 * are physical addresses. The following constant pointer can be
 * used as the IO-area pointer (it can be iounmapped as well, so the
 * analogy with PCI is quite large):
 */
#define __ISA_IO_base ((char __iomem *)(PAGE_OFFSET))

#define flush_write_buffers()

extern int iommu_bio_merge;
#define BIO_VMERGE_BOUNDARY iommu_bio_merge

/*
 * Convert a virtual cached pointer to an uncached pointer
 */
#define xlate_dev_kmem_ptr(p)	p

#endif /* __KERNEL__ */

#endif