* Philip Balister <philip@xxxxxxxxxxxx> [100224 14:28]: > On 02/24/2010 12:35 PM, Tony Lindgren wrote: > >* Philip Balister<philip@xxxxxxxxxxxx> [100224 11:31]: > >>I am trying to setup a dma operation to copy memory from GPMC > >>address space into RAM. The only examples using the omap-dma api use > >>hardware triggers. > >> > >>When I start a transfer, I end up with a DMA transaction error when > >>I start the transfer. > >> > >>Does anyone have a good example of a software transfer? Currently, I > >>am tracing the omap dma api to see how things map into the registers > >>.... > > > >Enjoy the GPMC timings. I recommend attaching a logic analyzer there > >to verify the things are right for the key lines if you have chance. > > > >Hmm I thought the hardware triggers were optional in at least > >drivers/usb/musb/tusb6010_omap.c.. Maybe I don't remember correctly. > > GPMC is easy :) Sounds like you just got lucky! :) > Basically, I have a device attached to a GPMC chip select and I need > to read/write to it. The GPNC bit is fine, we'd just like to use the > DMA controller to move the data. That should work, at least there has been several memory-to-memory dma test modules posted here over the years. Have you tried using OMAP_DMA_NO_DEVICE for omap_request_dma? Also search for omap dmatest or similar. Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
