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	This helps to clean up the include/ directory so that it only contains non-architecture-specific headers and also matches Linux's directory layout which many U-Boot developers are already familiar with. Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
		
			
				
	
	
		
			113 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			113 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *	FILE		bitfield.h
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|  *
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|  *	Version		1.1
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|  *	Author		Copyright (c) Marc A. Viredaz, 1998
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|  *			DEC Western Research Laboratory, Palo Alto, CA
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|  *	Date		April 1998 (April 1997)
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|  *	System		Advanced RISC Machine (ARM)
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|  *	Language	C or ARM Assembly
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|  *	Purpose		Definition of macros to operate on bit fields.
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|  */
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| 
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| 
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| #ifndef __BITFIELD_H
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| #define __BITFIELD_H
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| 
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| #ifndef __ASSEMBLY__
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| #define UData(Data)	((unsigned long) (Data))
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| #else
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| #define UData(Data)	(Data)
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| #endif
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| 
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| 
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| /*
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|  * MACRO: Fld
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|  *
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|  * Purpose
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|  *    The macro "Fld" encodes a bit field, given its size and its shift value
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|  *    with respect to bit 0.
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|  *
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|  * Note
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|  *    A more intuitive way to encode bit fields would have been to use their
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|  *    mask. However, extracting size and shift value information from a bit
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|  *    field's mask is cumbersome and might break the assembler (255-character
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|  *    line-size limit).
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|  *
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|  * Input
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|  *    Size		Size of the bit field, in number of bits.
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|  *    Shft		Shift value of the bit field with respect to bit 0.
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|  *
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|  * Output
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|  *    Fld		Encoded bit field.
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|  */
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| 
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| #define Fld(Size, Shft)	(((Size) << 16) + (Shft))
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| 
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| 
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| /*
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|  * MACROS: FSize, FShft, FMsk, FAlnMsk, F1stBit
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|  *
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|  * Purpose
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|  *    The macros "FSize", "FShft", "FMsk", "FAlnMsk", and "F1stBit" return
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|  *    the size, shift value, mask, aligned mask, and first bit of a
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|  *    bit field.
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|  *
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|  * Input
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|  *    Field		Encoded bit field (using the macro "Fld").
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|  *
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|  * Output
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|  *    FSize		Size of the bit field, in number of bits.
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|  *    FShft		Shift value of the bit field with respect to bit 0.
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|  *    FMsk		Mask for the bit field.
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|  *    FAlnMsk		Mask for the bit field, aligned on bit 0.
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|  *    F1stBit		First bit of the bit field.
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|  */
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| 
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| #define FSize(Field)	((Field) >> 16)
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| #define FShft(Field)	((Field) & 0x0000FFFF)
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| #define FMsk(Field)	(((UData (1) << FSize (Field)) - 1) << FShft (Field))
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| #define FAlnMsk(Field)	((UData (1) << FSize (Field)) - 1)
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| #define F1stBit(Field)	(UData (1) << FShft (Field))
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| 
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| 
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| /*
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|  * MACRO: FInsrt
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|  *
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|  * Purpose
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|  *    The macro "FInsrt" inserts a value into a bit field by shifting the
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|  *    former appropriately.
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|  *
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|  * Input
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|  *    Value		Bit-field value.
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|  *    Field		Encoded bit field (using the macro "Fld").
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|  *
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|  * Output
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|  *    FInsrt		Bit-field value positioned appropriately.
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|  */
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| 
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| #define FInsrt(Value, Field) \
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| 			(UData (Value) << FShft (Field))
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| 
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| 
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| /*
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|  * MACRO: FExtr
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|  *
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|  * Purpose
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|  *    The macro "FExtr" extracts the value of a bit field by masking and
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|  *    shifting it appropriately.
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|  *
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|  * Input
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|  *    Data		Data containing the bit-field to be extracted.
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|  *    Field		Encoded bit field (using the macro "Fld").
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|  *
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|  * Output
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|  *    FExtr		Bit-field value.
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|  */
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| 
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| #define FExtr(Data, Field) \
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| 			((UData (Data) >> FShft (Field)) & FAlnMsk (Field))
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| 
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| 
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| #endif /* __BITFIELD_H */
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