On Tue, 17 Apr 2018, 'Christoph Hellwig' wrote: > On Tue, Apr 17, 2018 at 10:54:37AM +0200, Thomas Gleixner wrote: > > The question was rather to have a list of PCI IDs for those chipsets which > > have the problem and set the 'disable' flag only for those. That makes a lot > > more sense than making a list of new chips which disable the disable flag. > > Agreed. > > There are a few other things I'd like to do in this area while we're > at it (I'm happy to do the work, not trying to offload it to David > or Thomas): > > (1) make the nodac flag a per-device flag. Set for every device > under one of the affected VIA bridges, or for all PCI devices > if the nodac command line option is used > (2) move that flag into the common struct device (or the to be > designed dma struct hanging off it in the future) and make that > bit handled in common code as there is a common Xilinx host > bridge with a 32-bit dma limitation > (3) kill of the forcesac option, which was a strange performance > tweak back in plain PCI days, which probably didn't even work > as expected to start with.
Sounds good.
