On Sat, May 1, 2010 at 3:44 PM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > On Sat, May 01, 2010 at 03:00:09PM -0700, Dan Williams wrote: >> Just to clarify are you nak'ing these patches for upstream inclusion >> until this testing occurs? Or do we just need a !ARCH_VERSATILE >> somewhere to allow any incompatibilities to be worked out later >> in-tree? > > What I don't want to do is to get into the situation where we throw > this patchset into the kernel and then find that we have to invent a > whole new implementation in the various primecell drivers to support > the Versatile hardware. > > Versatile has some MUXing on three of the DMA signals, so (eg) we > really don't want UARTs claiming DMAs just because they're in existence > and not in use - that would prevent DMAs from being used for (eg) AACI > or MMC. > > The alternative is that we could just take the attitude that Versatile/ > Realview will never have DMA support implemented, but that seems rather > silly, as they've tended to be the first platforms I get new CPU > architectures for. (This is why DMA coherency stuff on new architectures > tends to be left for others to do...) Ok, it will be good to have this approach vetted on a challenging arch. We'll see where things stand when the merge window opens. -- Dan -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
