Hi Wolfgang,

PPC: add accessor macros to clear and set bits in one shot

Although I think this is a good idea, I do not particularly like some details.

This patch adds macros from linux/include/asm-powerpc/io.h to clear and set bits in one shot using the in_be32, out_be32, etc. accessor functions. They are very handy to manipulate bits it I/O registers.

This patch is required for my forthcoming FSL NAND UPM driver re-write and the support for the TQM8548 module.

Signed-off-by: Wolfgang Grandegger wg@grandegger.com

include/asm-ppc/io.h | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)

Index: u-boot/include/asm-ppc/io.h

--- u-boot.orig/include/asm-ppc/io.h +++ u-boot/include/asm-ppc/io.h @@ -238,6 +238,34 @@ extern inline void out_be32(volatile uns __asm__ __volatile__("sync; stw%U0%X0 %1,%0" : "=m" (*addr) : "r" (val)); }

+/* access ports */ +#define setbits32(_addr, _v) out_be32((_addr), in_be32(_addr) | (_v)) +#define clrbits32(_addr, _v) out_be32((_addr), in_be32(_addr) & ~(_v))

+#define setbits16(_addr, _v) out_be16((_addr), in_be16(_addr) | (_v)) +#define clrbits16(_addr, _v) out_be16((_addr), in_be16(_addr) & ~(_v))

Below are versions for _{be,le} which makes total sense to me, but the variants here miss the endianness, _implicitely_ doing big-endian transfers. That is neither consistent, nor usable, i.e. how do I set a bit in a le-register?

+#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. These macros can be used to clear and

• • set multiple bits in a register using a single read-modify-write. 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.
• */

+#define clrsetbits(type, addr, clear, set) \

• out_##type((addr), (in_##type(addr) & ~(clear)) | (set))

+#define clrsetbits_be32(addr, clear, set) clrsetbits(be32, addr, clear, set) +#define clrsetbits_le32(addr, clear, set) clrsetbits(le32, addr, clear, set)

+#define clrsetbits_be16(addr, clear, set) clrsetbits(be16, addr, clear, set) +#define clrsetbits_le16(addr, clear, set) clrsetbits(le32, addr, clear, set)

Error --------------------------------------------------^^^^

+#define clrsetbits_8(addr, clear, set) clrsetbits(8, addr, clear, set)

/*

• Given a physical address and a length, return a virtual address
• that can be used to access the memory range with the caching

Cheers Detlev