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diff --git a/arch/arm/mach-sa1100/include/mach/bitfield.h b/arch/arm/mach-sa1100/include/mach/bitfield.h
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@@ -0,0 +1,113 @@
+/*
+ *      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 */