x86_io.h File Reference

gPXE I/O API for x86 More...

Go to the source code of this file.

Defines
#define	IOAPI_PREFIX_x86   __x86_
#define	X86_READX(_api_func, _type)
#define	X86_WRITEX(_api_func, _type)
#define	X86_INX(_insn_suffix, _type, _reg_prefix)
#define	X86_OUTX(_insn_suffix, _type, _reg_prefix)
Functions
	FILE_LICENCE (GPL2_OR_LATER)
static __always_inline unsigned long	IOAPI_INLINE (x86, phys_to_bus)(unsigned long phys_addr)
static __always_inline unsigned long	IOAPI_INLINE (x86, bus_to_phys)(unsigned long bus_addr)
static __always_inline void *	IOAPI_INLINE (x86, ioremap)(unsigned long bus_addr
	X86_READX (readw, uint16_t)
	X86_READX (readl, uint32_t)
	X86_WRITEX (writeb, uint8_t)
	X86_WRITEX (writew, uint16_t)
	X86_WRITEX (writel, uint32_t)
	X86_INX (b, uint8_t,"b")
	X86_INX (w, uint16_t,"w")
	X86_INX (l, uint32_t,"k")
	X86_OUTX (b, uint8_t,"b")
	X86_OUTX (w, uint16_t,"w")
	X86_OUTX (l, uint32_t,"k")
static __always_inline void	IOAPI_INLINE (x86, iodelay)(void)
static __always_inline void	IOAPI_INLINE (x86, mb)(void)

---

Detailed Description

gPXE I/O API for x86

i386 uses direct pointer dereferences for accesses to memory-mapped I/O space, and the inX/outX instructions for accesses to port-mapped I/O space.

64-bit atomic accesses (readq() and writeq()) use MMX instructions, and will crash original Pentium and earlier CPUs. Fortunately, no hardware that requires atomic 64-bit accesses will physically fit into a machine with such an old CPU anyway.

Definition in file x86_io.h.

---

Define Documentation

#define IOAPI_PREFIX_x86   __x86_

Definition at line 23 of file x86_io.h.

#define X86_READX	(	_api_func,
		_type		)

Value:

static inline __always_inline _type                                           \
IOAPI_INLINE ( x86, _api_func ) ( volatile _type *io_addr ) {                 \
        return *io_addr;                                                      \
}

#define X86_WRITEX	(	_api_func,
		_type		)

Value:

static inline __always_inline void                                            \
IOAPI_INLINE ( x86, _api_func ) ( _type data,                                 \
                                  volatile _type *io_addr ) {                 \
        *io_addr = data;                                                      \
}

Definition at line 75 of file x86_io.h.

#define X86_INX	(	_insn_suffix,
		_type,
		_reg_prefix		)

Value:

static inline __always_inline _type                                           \
IOAPI_INLINE ( x86, in ## _insn_suffix ) ( volatile _type *io_addr ) {        \
        _type data;                                                           \
        __asm__ __volatile__ ( "in" #_insn_suffix " %w1, %" _reg_prefix "0"   \
                               : "=a" ( data ) : "Nd" ( io_addr ) );          \
        return data;                                                          \
}                                                                             \
static inline __always_inline void                                            \
IOAPI_INLINE ( x86, ins ## _insn_suffix ) ( volatile _type *io_addr,          \
                                            _type *data,                      \
                                            unsigned int count ) {            \
        unsigned int discard_D;                                               \
        __asm__ __volatile__ ( "rep ins" #_insn_suffix                        \
                               : "=D" ( discard_D )                           \
                               : "d" ( io_addr ), "c" ( count ),              \
                                 "0" ( data ) );                              \
}

Definition at line 90 of file x86_io.h.

#define X86_OUTX	(	_insn_suffix,
		_type,
		_reg_prefix		)

Value:

static inline __always_inline void                                            \
IOAPI_INLINE ( x86, out ## _insn_suffix ) ( _type data,                       \
                                            volatile _type *io_addr ) {       \
        __asm__ __volatile__ ( "out" #_insn_suffix " %" _reg_prefix "0, %w1"  \
                               : : "a" ( data ), "Nd" ( io_addr ) );          \
}                                                                             \
static inline __always_inline void                                            \
IOAPI_INLINE ( x86, outs ## _insn_suffix ) ( volatile _type *io_addr,         \
                                             const _type *data,               \
                                             unsigned int count ) {           \
        unsigned int discard_S;                                               \
        __asm__ __volatile__ ( "rep outs" #_insn_suffix                       \
                               : "=S" ( discard_S )                           \
                               : "d" ( io_addr ), "c" ( count ),              \
                                 "0" ( data ) );                              \
}

Definition at line 112 of file x86_io.h.

---

Function Documentation

FILE_LICENCE

(

GPL2_OR_LATER

)

static __always_inline unsigned long IOAPI_INLINE	(	x86	,
		phys_to_bus
	)			[inline, static]

Definition at line 37 of file x86_io.h.

                                                              {
        return phys_addr;
}

static __always_inline unsigned long IOAPI_INLINE	(	x86	,
		bus_to_phys
	)			[inline, static]

Definition at line 42 of file x86_io.h.

                                                             {
        return bus_addr;
}

static __always_inline void* IOAPI_INLINE	(	x86	,
		ioremap
	)			[inline, static]

X86_READX	(	readw	,
		uint16_t
	)

X86_READX	(	readl	,
		uint32_t
	)

X86_WRITEX	(	writeb	,
		uint8_t
	)

X86_WRITEX	(	writew	,
		uint16_t
	)

X86_WRITEX	(	writel	,
		uint32_t
	)

X86_INX	(	b	,
		uint8_t	,
		"b"
	)

X86_INX	(	w	,
		uint16_t	,
		"w"
	)

X86_INX	(	l	,
		uint32_t	,
		"k"
	)

X86_OUTX	(	b	,
		uint8_t	,
		"b"
	)

X86_OUTX	(	w	,
		uint16_t	,
		"w"
	)

X86_OUTX	(	l	,
		uint32_t	,
		"k"
	)

static __always_inline void IOAPI_INLINE	(	x86	,
		iodelay
	)			[inline, static]

Definition at line 139 of file x86_io.h.

References __asm__().

                                       {
        __asm__ __volatile__ ( "outb %al, $0x80" );
}

static __always_inline void IOAPI_INLINE	(	x86	,
		mb
	)			[inline, static]

Definition at line 149 of file x86_io.h.

References __asm__().

                                  {
        __asm__ __volatile__ ( "lock; addl $0, 0(%%esp)" : : : "memory" );
}