mirror of https://github.com/ipxe/ipxe.git
51 lines
1.2 KiB
C
51 lines
1.2 KiB
C
#ifndef _GPXE_BITBASH_H
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#define _GPXE_BITBASH_H
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/** @file
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*
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* Bit-bashing interfaces
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*
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*/
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struct bit_basher;
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/** Bit-bashing operations */
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struct bit_basher_operations {
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/**
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* Set/clear output bit
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*
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* @v basher Bit-bashing interface
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* @v bit_id Bit number
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* @v data Value to write
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*
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* @c data will be 0 if a logic 0 should be written (i.e. the
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* bit should be cleared), or -1UL if a logic 1 should be
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* written (i.e. the bit should be set). This is done so that
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* the method may simply binary-AND @c data with the
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* appropriate bit mask.
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*/
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void ( * write ) ( struct bit_basher *basher, unsigned int bit_id,
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unsigned long data );
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/**
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* Read input bit
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*
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* @v basher Bit-bashing interface
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* @v bit_id Bit number
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* @ret zero Input is a logic 0
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* @ret non-zero Input is a logic 1
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*/
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int ( * read ) ( struct bit_basher *basher, unsigned int bit_id );
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};
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/** A bit-bashing interface */
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struct bit_basher {
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/** Bit-bashing operations */
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struct bit_basher_operations *op;
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};
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extern void write_bit ( struct bit_basher *basher, unsigned int bit_id,
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unsigned long data );
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extern int read_bit ( struct bit_basher *basher, unsigned int bit_id );
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#endif /* _GPXE_BITBASH_H */
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