Re: simple framebuffer slower by factor of 20, on socfpga (arm) platform

[Pavel Machek]

Hi!

On Fri 2015-04-10 12:35:52, Archit Taneja wrote:
> >That said, if the fb is in RAM, and is only written by the CPU, I think
> >a normal memcpy() for fb_memcpy_fromfb() should be fine...
> 
> I didn't test for performance regressions when I posted this patch.
> 
> A look at _memcpy_fromio in arch/arm/kernel/io.c shows that readb() is used
> all the time, even when the source and destination addresses are aligned for
> larger reads to be possible. Other archs seem to use readl() or readq() when
> they can. Maybe that makes memcpy_fromio slower than the implementation of
> memcpy on arm?

Ok, can you prepare a patch for me to try? Or should we just revert
the original commit?
									Pavel
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