On Mon, Sep 15, 2014 at 05:32:05PM +0100, Jon Masters wrote: > On 09/15/2014 11:52 AM, Catalin Marinas wrote: > > Hi Jon, > > > > On Sun, Sep 14, 2014 at 03:38:07AM +0100, Jon Masters wrote: > >> commit 6ecba8eb51b7d23fda66388a5420be7d8688b186 > >> Author: Catalin Marinas <catalin.mari...@arm.com> > >> Date: Fri Apr 25 15:31:45 2014 +0100 > >> > >> arm64: Use bus notifiers to set per-device coherent DMA ops > >> > >> Thus at this point, on 32-bit systems, we have defined this function: > >> > >> set_arch_dma_coherent_ops > > > > It was a timing issue that they are not in sync. I would have used > > set_arch_dma_coherent_ops() but it wasn't very clear when it gets merged > > and changing the default on arm64 broke some other assumptions, so a > > temporary fix. > > Ok. So arm64 will automatically switch over to set_arch_dma_coherent_ops > (once it's there, it will be called automatically anyway because it's in > the callchain anyway already).
I still need to figure out if set_arch_dma_coherent_ops() is called for AMBA devices. > For the moment, on our internal PCI trees, we'll add a notifier and wait > for upstream to get PCI support and figure this out as part of that > activity. In the case of ACPI, I'm still pushing for _CCA methods to be > added by default because it makes sense to be verbose in describing > platform hardware devices, even in spite of default. Anyway, with ACPI it would probably make sense to keep the hooks (with the recursive parent check), so set_arch_dma_coherent_ops() wouldn't buy us much (especially if it's only for platform devices). -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
