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diff --git a/arch/arm/include/asm/arch-sa1100/bitfield.h b/arch/arm/include/asm/arch-sa1100/bitfield.h
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+/*
+ *	FILE		bitfield.h
+ *
+ *	Version		1.1
+ *	Author		Copyright (c) Marc A. Viredaz, 1998
+ *			DEC Western Research Laboratory, Palo Alto, CA
+ *	Date		April 1998 (April 1997)
+ *	System		Advanced RISC Machine (ARM)
+ *	Language	C or ARM Assembly
+ *	Purpose		Definition of macros to operate on bit fields.
+ */
+
+
+#ifndef __BITFIELD_H
+#define __BITFIELD_H
+
+#ifndef __ASSEMBLY__
+#define UData(Data)	((unsigned long) (Data))
+#else
+#define UData(Data)	(Data)
+#endif
+
+
+/*
+ * MACRO: Fld
+ *
+ * Purpose
+ *    The macro "Fld" encodes a bit field, given its size and its shift value
+ *    with respect to bit 0.
+ *
+ * Note
+ *    A more intuitive way to encode bit fields would have been to use their
+ *    mask. However, extracting size and shift value information from a bit
+ *    field's mask is cumbersome and might break the assembler (255-character
+ *    line-size limit).
+ *
+ * Input
+ *    Size		Size of the bit field, in number of bits.
+ *    Shft		Shift value of the bit field with respect to bit 0.
+ *
+ * Output
+ *    Fld		Encoded bit field.
+ */
+
+#define Fld(Size, Shft)	(((Size) << 16) + (Shft))
+
+
+/*
+ * MACROS: FSize, FShft, FMsk, FAlnMsk, F1stBit
+ *
+ * Purpose
+ *    The macros "FSize", "FShft", "FMsk", "FAlnMsk", and "F1stBit" return
+ *    the size, shift value, mask, aligned mask, and first bit of a
+ *    bit field.
+ *
+ * Input
+ *    Field		Encoded bit field (using the macro "Fld").
+ *
+ * Output
+ *    FSize		Size of the bit field, in number of bits.
+ *    FShft		Shift value of the bit field with respect to bit 0.
+ *    FMsk		Mask for the bit field.
+ *    FAlnMsk		Mask for the bit field, aligned on bit 0.
+ *    F1stBit		First bit of the bit field.
+ */
+
+#define FSize(Field)	((Field) >> 16)
+#define FShft(Field)	((Field) & 0x0000FFFF)
+#define FMsk(Field)	(((UData (1) << FSize (Field)) - 1) << FShft (Field))
+#define FAlnMsk(Field)	((UData (1) << FSize (Field)) - 1)
+#define F1stBit(Field)	(UData (1) << FShft (Field))
+
+
+/*
+ * MACRO: FInsrt
+ *
+ * Purpose
+ *    The macro "FInsrt" inserts a value into a bit field by shifting the
+ *    former appropriately.
+ *
+ * Input
+ *    Value		Bit-field value.
+ *    Field		Encoded bit field (using the macro "Fld").
+ *
+ * Output
+ *    FInsrt		Bit-field value positioned appropriately.
+ */
+
+#define FInsrt(Value, Field) \
+			(UData (Value) << FShft (Field))
+
+
+/*
+ * MACRO: FExtr
+ *
+ * Purpose
+ *    The macro "FExtr" extracts the value of a bit field by masking and
+ *    shifting it appropriately.
+ *
+ * Input
+ *    Data		Data containing the bit-field to be extracted.
+ *    Field		Encoded bit field (using the macro "Fld").
+ *
+ * Output
+ *    FExtr		Bit-field value.
+ */
+
+#define FExtr(Data, Field) \
+			((UData (Data) >> FShft (Field)) & FAlnMsk (Field))
+
+
+#endif /* __BITFIELD_H */