u-boot/include/asm-i386/io.h
Kumar Gala 65e43a1063 Introduce virt_to_phys()
virt_to_phys() returns the physical address given a virtual. In most
cases this will be just the input value as the vast majority of
systems run in a 1:1 mode.

However in systems that are not running this way it should report the
physical address or ~0 if no mapping exists for the given virtual
address.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-12-15 22:04:29 +01:00

237 lines
6.2 KiB
C

#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>
*/
#define IO_SPACE_LIMIT 0xffff
#ifdef __KERNEL__
/*
* 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.
*/
#define readb(addr) (*(volatile unsigned char *) (addr))
#define readw(addr) (*(volatile unsigned short *) (addr))
#define readl(addr) (*(volatile unsigned int *) (addr))
#define __raw_readb readb
#define __raw_readw readw
#define __raw_readl readl
#define writeb(b,addr) (*(volatile unsigned char *) (addr) = (b))
#define writew(b,addr) (*(volatile unsigned short *) (addr) = (b))
#define writel(b,addr) (*(volatile unsigned int *) (addr) = (b))
#define __raw_writeb writeb
#define __raw_writew writew
#define __raw_writel writel
#define memset_io(a,b,c) memset((a),(b),(c))
#define memcpy_fromio(a,b,c) memcpy((a),(b),(c))
#define memcpy_toio(a,b,c) memcpy((a),(b),(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_readb(a) readb((a))
#define isa_readw(a) readw((a))
#define isa_readl(a) readl((a))
#define isa_writeb(b,a) writeb(b,(a))
#define isa_writew(w,a) writew(w,(a))
#define isa_writel(l,a) writel(l,(a))
#define isa_memset_io(a,b,c) memset_io((a),(b),(c))
#define isa_memcpy_fromio(a,b,c) memcpy_fromio((a),(b),(c))
#define isa_memcpy_toio(a,b,c) memcpy_toio((a),(b),(c))
static inline int check_signature(unsigned long io_addr,
const unsigned char *signature, int length)
{
int retval = 0;
do {
if (readb(io_addr) != *signature)
goto out;
io_addr++;
signature++;
length--;
} while (length);
retval = 1;
out:
return retval;
}
/**
* isa_check_signature - find BIOS signatures
* @io_addr: mmio address to check
* @signature: signature block
* @length: length of signature
*
* Perform a signature comparison with the ISA mmio address io_addr.
* Returns 1 on a match.
*
* This function is deprecated. New drivers should use ioremap and
* check_signature.
*/
static inline int isa_check_signature(unsigned long io_addr,
const unsigned char *signature, int length)
{
int retval = 0;
do {
if (isa_readb(io_addr) != *signature)
goto out;
io_addr++;
signature++;
length--;
} while (length);
retval = 1;
out:
return retval;
}
#endif /* __KERNEL__ */
#ifdef SLOW_IO_BY_JUMPING
#define __SLOW_DOWN_IO "\njmp 1f\n1:\tjmp 1f\n1:"
#else
#define __SLOW_DOWN_IO "\noutb %%al,$0x80"
#endif
#ifdef REALLY_SLOW_IO
#define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO __SLOW_DOWN_IO
#else
#define __FULL_SLOW_DOWN_IO __SLOW_DOWN_IO
#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"
#define __OUT(s,s1,x) \
__OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "Nd" (port)); } \
__OUT1(s##_p,x) __OUT2(s,s1,"w") __FULL_SLOW_DOWN_IO : : "a" (value), "Nd" (port));}
#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") __FULL_SLOW_DOWN_IO : "=a" (_v) : "Nd" (port) ,##i ); return _v; }
#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)
static inline void sync(void)
{
}
/*
* Given a physical address and a length, return a virtual address
* that can be used to access the memory range with the caching
* properties specified by "flags".
*/
#define MAP_NOCACHE (0)
#define MAP_WRCOMBINE (0)
#define MAP_WRBACK (0)
#define MAP_WRTHROUGH (0)
static inline void *
map_physmem(phys_addr_t paddr, unsigned long len, unsigned long flags)
{
return (void *)paddr;
}
/*
* Take down a mapping set up by map_physmem().
*/
static inline void unmap_physmem(void *vaddr, unsigned long flags)
{
}
static inline phys_addr_t virt_to_phys(void * vaddr)
{
return (phys_addr_t)(vaddr);
}
#endif