Signed-off-by: Jason Fan <fanja...@google.com>
---
include/qemu/bitops.h | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/include/qemu/bitops.h b/include/qemu/bitops.h
index 2c0a2fe751..d01c4b42f2 100644
--- a/include/qemu/bitops.h
+++ b/include/qemu/bitops.h
@@ -459,6 +459,32 @@ static inline int64_t sextract64(uint64_t value, int
start, int length)
return ((int64_t)(value << (64 - length - start))) >> (64 - length);
}
+/**
+ * deposit8:
+ * @value: initial value to insert bit field into
+ * @start: the lowest bit in the bit field (numbered from 0)
+ * @length: the length of the bit field
+ * @fieldval: the value to insert into the bit field
+ *
+ * Deposit @fieldval into the 8 bit @value at the bit field specified
+ * by the @start and @length parameters, and return the modified
+ * @value. Bits of @value outside the bit field are not modified.
+ * Bits of @fieldval above the least significant @length bits are
+ * ignored. The bit field must lie entirely within the 8 bit word.
+ * It is valid to request that all 8 bits are modified (ie @length
+ * 8 and @start 0).
+ *
+ * Returns: the modified @value.
+ */
+static inline uint8_t deposit8(uint8_t value, int start, int length,
+ uint8_t fieldval)
+{
+ uint8_t mask = 0xFF;
+ assert(start >= 0 && length > 0 && length <= 8 - start);
+ mask = (mask >> (8 - length)) << start;
+ return (value & ~mask) | ((fieldval << start) & mask);
+}
+
/**
* deposit32:
* @value: initial value to insert bit field into
--
2.46.0.295.g3b9ea8a38a-goog
