include/asm-m68knommu/io_hw_swap.h

   1 #ifndef _M68K_IO_HW_SWAP_H
   2 #define _M68K_IO_HW_SWAP_H
   3
   4 /*
   5  * swap functions are sometimes needed to interface little-endian hardware
   6  */
   7 static inline unsigned short _swapw(volatile unsigned short v)
   8 {
   9     return ((v << 8) | (v >> 8));
  10 }
  11
  12 static inline unsigned int _swapl(volatile unsigned long v)
  13 {
  14     return ((v << 24) | ((v & 0xff00) << 8) | ((v & 0xff0000) >> 8) | (v >> 24));
  15 }
  16
  17 /*
  18  * readX/writeX() are used to access memory mapped devices. On some
  19  * architectures the memory mapped IO stuff needs to be accessed
  20  * differently. On the m68k architecture, we just read/write the
  21  * memory location directly.
  22  */
  23 /* ++roman: The assignments to temp. vars avoid that gcc sometimes generates
  24  * two accesses to memory, which may be undesireable for some devices.
  25  */
  26 #define readb(addr) \
  27     ({ unsigned char __v = (*(volatile unsigned char *) (addr)); __v; })
  28 #define readw(addr) \
  29     ({ unsigned short __v = (*(volatile unsigned short *) (addr)); __v; })
  30 #define readl(addr) \
  31     ({ unsigned int __v = (*(volatile unsigned int *) (addr)); __v; })
  32
  33 #define writeb(b,addr) ((*(volatile unsigned char *) (addr)) = (b))
  34 #define writew(b,addr) ((*(volatile unsigned short *) (addr)) = (b))
  35 #define writel(b,addr) ((*(volatile unsigned int *) (addr)) = (b))
  36
  37 /* There is no difference between I/O and memory on 68k, these are the same */
  38 #define inb(addr) \
  39     ({ unsigned char __v = (*(volatile unsigned char *) (addr)); __v; })
  40 #define inw(addr) \
  41     ({ unsigned short __v = (*(volatile unsigned short *) (addr)); \
  42        _swapw(__v); })
  43 #define inl(addr) \
  44     ({ unsigned int __v = (*(volatile unsigned int *) (addr)); _swapl(__v); })
  45
  46 #define outb(b,addr) ((*(volatile unsigned char *) (addr)) = (b))
  47 #define outw(b,addr) ((*(volatile unsigned short *) (addr)) = (_swapw(b)))
  48 #define outl(b,addr) ((*(volatile unsigned int *) (addr)) = (_swapl(b)))
  49
  50 /* FIXME: these need to be optimized.  Watch out for byte swapping, they
  51  * are used mostly for Intel devices... */
  52 #define outsw(addr,buf,len) \
  53     ({ unsigned short * __p = (unsigned short *)(buf); \
  54        unsigned short * __e = (unsigned short *)(__p) + (len); \
  55        while (__p < __e) { \
  56           *(volatile unsigned short *)(addr) = *__p++;\
  57        } \
  58      })
  59
  60 #define insw(addr,buf,len) \
  61     ({ unsigned short * __p = (unsigned short *)(buf); \
  62        unsigned short * __e = (unsigned short *)(__p) + (len); \
  63        while (__p < __e) { \
  64           *(__p++) = *(volatile unsigned short *)(addr); \
  65        } \
  66      })
  67
  68
  69 static inline unsigned char get_user_byte_io(const char * addr)
  70 {
  71         register unsigned char _v;
  72
  73         __asm__ __volatile__ ("moveb %1,%0":"=dm" (_v):"m" (*addr));
  74         return _v;
  75 }
  76 #define inb_p(addr) get_user_byte_io((char *)(addr))
  77
  78 static inline void put_user_byte_io(char val,char *addr)
  79 {
  80         __asm__ __volatile__ ("moveb %0,%1"
  81                               : /* no outputs */
  82                               :"idm" (val),"m" (*addr)
  83                               : "memory");
  84 }
  85 #define outb_p(x,addr) put_user_byte_io((x),(char *)(addr))
  86
  87 /*
  88  * Change virtual addresses to physical addresses and vv.
  89  * These are trivial on the 1:1 Linux/i386 mapping (but if we ever
  90  * make the kernel segment mapped at 0, we need to do translation
  91  * on the i386 as well)
  92  */
  93 extern unsigned long mm_vtop(unsigned long addr);
  94 extern unsigned long mm_ptov(unsigned long addr);
  95
  96 extern inline unsigned long virt_to_phys(volatile void * address)
  97 {
  98         return (unsigned long) mm_vtop((unsigned long)address);
  99 }
 100
 101 extern inline void * phys_to_virt(unsigned long address)
 102 {
 103         return (void *) mm_ptov(address);
 104 }
 105
 106 /*
 107  * IO bus memory addresses are also 1:1 with the physical address
 108  */
 109 #define virt_to_bus virt_to_phys
 110 #define bus_to_virt phys_to_virt
 111
 112
 113 #endif /* _M68K_IO_HW_SWAP_H */