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@@ -27,6 +27,12 @@
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* old = bitfield_extract(old_reg_val, 10, 5);
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* new_reg_val = bitfield_replace(old_reg_val, 10, 5, new);
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*
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+ * or
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+ *
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+ * mask = bitfield_mask(10, 5);
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+ * old = bitfield_extract_by_mask(old_reg_val, mask);
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+ * new_reg_val = bitfield_replace_by_mask(old_reg_val, mask, new);
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+ *
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* The numbers 10 and 5 could for example come from data
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* tables which describe all bitfields in all registers.
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*/
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@@ -56,3 +62,29 @@ static inline uint bitfield_replace(uint reg_val, uint shift, uint width,
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return (reg_val & ~mask) | ((bitfield_val << shift) & mask);
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}
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+
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+/* Produces a shift of the bitfield given a mask */
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+static inline uint bitfield_shift(uint mask)
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+{
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+ return mask ? ffs(mask) - 1 : 0;
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+}
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+
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+/* Extract the value of a bitfield found within a given register value */
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+static inline uint bitfield_extract_by_mask(uint reg_val, uint mask)
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+{
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+ uint shift = bitfield_shift(mask);
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+
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+ return (reg_val & mask) >> shift;
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+}
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+
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+/*
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+ * Replace the value of a bitfield found within a given register value
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+ * Returns the newly modified uint value with the replaced field.
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+ */
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+static inline uint bitfield_replace_by_mask(uint reg_val, uint mask,
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+ uint bitfield_val)
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+{
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+ uint shift = bitfield_shift(mask);
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+
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+ return (reg_val & ~mask) | ((bitfield_val << shift) & mask);
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+}
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