Messages in this thread | | | Date | Fri, 24 Jan 2020 15:07:51 +0100 | From | Thomas Bogendoerfer <> | Subject | Re: [PATCH] MIPS: Introduce aligned IO memory operations |
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On Wed, Jan 22, 2020 at 10:45:06AM -0800, Paul Burton wrote: > Hi Jiaxun, > > On Tue, Jan 14, 2020 at 08:23:43PM +0800, Jiaxun Yang wrote: > > Some platforms, such as Loongson64 or QEMU/KVM, don't support unaligned > > instructions like lwl or lwr in IO memory access. However, our current > > IO memcpy/memset is wired to the generic implementation, which leads > > to a fatal result. > > Hmm, I wonder if we should just do this unconditionally on all systems. > I can't think of a reason it'd ever be a good idea to use lwl/lwr on an > MMIO device. Any thoughts on that?
depends on the type of device. I can see benefits for framebuffers and memory devices since memset/memcpy are more optimised than the function in this patch.
Thomas.
-- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]
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