Skip to content
Snippets Groups Projects
io.h 6.17 KiB
Newer Older
  • Learn to ignore specific revisions
  • #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
    
    Wolfgang Denk's avatar
    Wolfgang Denk committed
     *	@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.
     */
    
    Wolfgang Denk's avatar
    Wolfgang Denk committed
    
    
    
    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)); } \
    
    Wolfgang Denk's avatar
    Wolfgang Denk committed
    __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; } \
    
    Wolfgang Denk's avatar
    Wolfgang Denk committed
    __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)
    
    
    /*
     * 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)
    {
    
    }
    
    
    Kumar Gala's avatar
    Kumar Gala committed
    static inline phys_addr_t virt_to_phys(void * vaddr)
    {
    	return (phys_addr_t)(vaddr);
    }