[POWERPC] add clrsetbits macros

Timur Tabi timur at freescale.com
Thu Aug 23 03:47:16 EST 2007


This patch adds the clrsetbits() macro, which is used to set and clear
multiple bits in a single read-modify-write operation.  Specify the bits to
clear in the 'clear' parameter and the bits to set in the 'set' parameter.
These macros can also be used to set a multiple-bit bit pattern using a mask,
by specifying the mask in the 'clear' parameter and the new bit pattern in the
'set' parameter.  The 'type' parameter is used to specify the size and endian.

Signed-off-by: Timur Tabi <timur at freescale.com>
---

Replace multiple macros with a single one that uses macro concatenation to
handle the endian/size.

 include/asm-powerpc/io.h |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/include/asm-powerpc/io.h b/include/asm-powerpc/io.h
index 4c0b550..030ed4e 100644
--- a/include/asm-powerpc/io.h
+++ b/include/asm-powerpc/io.h
@@ -737,6 +737,19 @@ static inline void * bus_to_virt(unsigned long address)
 #define setbits8(_addr, _v) out_8((_addr), in_8(_addr) |  (_v))
 #define clrbits8(_addr, _v) out_8((_addr), in_8(_addr) & ~(_v))
 
+/* Clear and set bits in one shot.  This macrocan be used to clear and set
+ * multiple bits in a register using a single read-modify-write.  It can
+ * also be used to set a multiple-bit bit pattern using a mask, by
+ * specifying the mask in the 'clear' parameter and the new bit pattern in
+ * the 'set' parameter.
+ *
+ * For 'type', specify 8, le16, be16, le32, be32, le64, or be64.  The latter
+ * two only work on 64-bit PowerPC (__powerpc64__ is defined).
+ */
+
+#define clrsetbits(type, addr, clear, set) \
+	out_##type((addr), (in_##type(addr) & ~(clear)) | (set))
+
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_POWERPC_IO_H */
-- 
1.5.2.4




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