Hi Detlev,
Detlev Zundel wrote:
> 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 <[EMAIL PROTECTED]>
>> ---
>> 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 --------------------------------------------------^^^^
Ah, oh, I blindly copied that code from Linux include/asm-powerpc/io.h.
A revised patch addressing the above issues will follow.
Wolfgang.
-------------------------------------------------------------------------
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://sourceforge.net/services/buy/index.php
_______________________________________________
U-Boot-Users mailing list
U-Boot-Users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/u-boot-users
