[PATCH] dmaengine: pl330: Fix linker error "undefined reference to `__aeabi_uldivmod'"

Joe Perches joe at perches.com
Thu Nov 13 10:28:44 PST 2014

On Thu, 2014-11-13 at 18:19 +0000, Jon Medhurst (Tixy) wrote:
> There are many ways to code the limiting of the burst width, but as it
> starts out as the data bus width the DMA can handle (maximum 16 bytes)
> then at most we'll be going round the existing while loop 4 times so I
> don't think it's that much overhead, and probably less code size than
> using ffs.

For arm, isn't ffs just a few instruction with no loops?

> And as the driver has been broken for the unaligned memcpy case since
> the day it was added then I can't see that anyone is actually using it
> that way anyway, so all existing users (if any) must already be doing
> bus aligned copies and the current while loop will iterate zero times.

That's probably right, I just don't like reading
while loops where ffs/fls might be suitable.

> That's probably enough bikeshedding from me :-)

;)  Me too.  cheers, Joe

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