On Thu, May 23, 2019 at 11:04:03AM +0000, S.j. Wang wrote: > > On Thu, May 23, 2019 at 09:53:42AM +0000, S.j. Wang wrote: > > > > > + /* > > > > > + * Add fifo reset here, because the regcache_sync will > > > > > + * write one more data to ETDR. > > > > > + * Which will cause channel shift. > > > > > > > > Sounds like a bug to me...should fix it first by marking the data > > > > registers as volatile. > > > > > > > The ETDR is a writable register, it is not volatile. Even we change it > > > to Volatile, I don't think we can't avoid this issue. for the > > > regcache_sync Just to write this register, it is correct behavior. > > > > Is that so? Quoting the comments of regcache_sync(): > > "* regcache_sync - Sync the register cache with the hardware. > > * > > * @map: map to configure. > > * > > * Any registers that should not be synced should be marked as > > * volatile." > > > > If regcache_sync() does sync volatile registers too as you said, I don't > > mind > > having this FIFO reset WAR for now, though I think this mismatch between > > the comments and the actual behavior then should get people's attention. > > > > Thank you > > ETDR is not volatile, if we mark it is volatile, is it correct?
Well, you have a point -- it might not be ideally true, but it sounds like a correct fix to me according to this comments. We can wait for Mark's comments or just send a patch to the mail list for review. Thanks you
