Re: [PATCH v4 00/14] DMA Engine support for AM33XX
On Friday 11 January 2013, Matt Porter wrote: > We have tightly coupled the link-time dependency for > omap_dma_filter_fn by going down the path of using > dma_request_slave_channel_compat() as Tony suggested to avoid extra > ifdefry. > > That dependency will go away naturally if all the "legacy" OMAP platforms > were required to only boot from DT...just as a newly added SoCs are. > > Are you suggesting unwinding the _compat() approach? No, I was thinking we could define omap_dma_filter_fn to NULL for the DT-only case. Arnd ___ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
Re: [PATCH v4 00/14] DMA Engine support for AM33XX
On Fri, Jan 11, 2013 at 11:40:41AM +, Arnd Bergmann wrote: > On Friday 11 January 2013, Matt Porter wrote: > > The approach taken is similar to how OMAP DMA is being converted to > > DMA Engine support. With the functional EDMA private API already > > existing in mach-davinci/dma.c, we first move that to an ARM common > > area so it can be shared. Adding DT and runtime PM support to the > > private EDMA API implementation allows it to run on AM33xx. AM33xx > > only boots using DT so we leverage Jon's generic DT DMA helpers to > > register EDMA DMAC with the of_dma framework and then add support > > for calling the dma_request_slave_channel() API to both the mmc > > and spi drivers. > > I think this looks very good. What I wonder is whether we should > make the non-DT parts of the dmaengine driver compile-time > conditional on CONFIG_ATAGS though, so the slave drivers don't > have a link-time dependency on the dmaengine driver's > omap_dma_filter_fn symbol when building without ATAGS support. We have tightly coupled the link-time dependency for omap_dma_filter_fn by going down the path of using dma_request_slave_channel_compat() as Tony suggested to avoid extra ifdefry. That dependency will go away naturally if all the "legacy" OMAP platforms were required to only boot from DT...just as a newly added SoCs are. Are you suggesting unwinding the _compat() approach? -Matt ___ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
Re: [PATCH v4 00/14] DMA Engine support for AM33XX
On Friday 11 January 2013, Matt Porter wrote: > The approach taken is similar to how OMAP DMA is being converted to > DMA Engine support. With the functional EDMA private API already > existing in mach-davinci/dma.c, we first move that to an ARM common > area so it can be shared. Adding DT and runtime PM support to the > private EDMA API implementation allows it to run on AM33xx. AM33xx > only boots using DT so we leverage Jon's generic DT DMA helpers to > register EDMA DMAC with the of_dma framework and then add support > for calling the dma_request_slave_channel() API to both the mmc > and spi drivers. I think this looks very good. What I wonder is whether we should make the non-DT parts of the dmaengine driver compile-time conditional on CONFIG_ATAGS though, so the slave drivers don't have a link-time dependency on the dmaengine driver's omap_dma_filter_fn symbol when building without ATAGS support. Arnd ___ Davinci-linux-open-source mailing list Davinci-linux-open-source@linux.davincidsp.com http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
