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#ifndef _IPXE_BITBASH_H
#define _IPXE_BITBASH_H
/** @file
*
* Bit-bashing interfaces
*
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
struct bit_basher;
/** Bit-bashing operations */
struct bit_basher_operations {
/**
* Open bit-bashing interface (optional)
*
* @v basher Bit-bashing interface
*/
void ( * open ) ( struct bit_basher *basher );
/**
* Close bit-bashing interface (optional)
*
* @v basher Bit-bashing interface
*/
void ( * close ) ( struct bit_basher *basher );
/**
* Set/clear output bit
*
* @v basher Bit-bashing interface
* @v bit_id Bit number
* @v data Value to write
*
* @c data will be 0 if a logic 0 should be written (i.e. the
* bit should be cleared), or -1UL if a logic 1 should be
* written (i.e. the bit should be set). This is done so that
* the method may simply binary-AND @c data with the
* appropriate bit mask.
*/
void ( * write ) ( struct bit_basher *basher, unsigned int bit_id,
unsigned long data );
/**
* Read input bit
*
* @v basher Bit-bashing interface
* @v bit_id Bit number
* @ret zero Input is a logic 0
* @ret non-zero Input is a logic 1
*/
int ( * read ) ( struct bit_basher *basher, unsigned int bit_id );
};
/** A bit-bashing interface */
struct bit_basher {
/** Bit-bashing operations */
struct bit_basher_operations *op;
};
/**
* Open bit-bashing interface
*
* @v basher Bit-bashing interface
*/
static inline void open_bit ( struct bit_basher *basher ) {
if ( basher->op->open )
basher->op->open ( basher );
}
/**
* Close bit-bashing interface
*
* @v basher Bit-bashing interface
*/
static inline void close_bit ( struct bit_basher *basher ) {
if ( basher->op->close )
basher->op->close ( basher );
}
extern void write_bit ( struct bit_basher *basher, unsigned int bit_id,
unsigned long data );
extern int read_bit ( struct bit_basher *basher, unsigned int bit_id );
#endif /* _IPXE_BITBASH_H */
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