Re: [PATCH 13/21] arc: dma-mapping: skip invalidating before bidirectional DMA
Shahab Vahedi <[email protected]>
| Newsgroups | gmane.linux.ports.m68k,gmane.linux.kernel,gmane.linux.kernel.arc,gmane.linux.ports.arm.kernel,gmane.linux.ports.hexagon,gmane.linux.ports.mips,gmane.linux.ports.parisc,gmane.linux.ports.ppc64.devel,gmane.linux.ports.riscv,gmane.linux.ports.sh.devel,gmane.linux.ports.sparc |
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| Message-ID | <[email protected]> |
On 4/2/23 08:52, Vineet Gupta wrote: > CC Shahab > > On 3/27/23 17:43, Arnd Bergmann wrote: >> From: Arnd Bergmann<[email protected]> >> >> Some architectures that need to invalidate buffers after bidirectional >> DMA because of speculative prefetching only do a simpler writeback >> before that DMA, while architectures that don't need to do the second >> invalidate tend to have a combined writeback+invalidate before the >> DMA. >> >> arc is one of the architectures that does both, which seems unnecessary. >> >> Change it to behave like arm/arm64/xtensa instead, and use just a >> writeback before the DMA when we do the invalidate afterwards. >> >> Signed-off-by: Arnd Bergmann<[email protected]> > > Reviewed-by: Vineet Gupta <[email protected]> > > Shahab can you give this a spin on hsdk - run glibc testsuite over ssh and make sure nothing strange happens. > > Thx, > -Vineet On it. -- Shahab