On Thursday 16 December 2010 18:37:38 David Sin wrote: > I'm not sure exactly how DRM/GEM works.. What functionality do you think is > overlapping? The main feature, aside from reduced page accesses, of the DMM > hw block is to provide physically contiguous 2 dimensional memory blocks for > image and video processing. This hw sits between the interconnect and the > ext memory interface in the OMAP, and contains an MMU-like address traslator > for "virtually" physically contiguous memory and sdram pages. As far as I can tell, both DMM and GEM at a high level manage objects in video memory. The IOMMU that you have on the Omap hardware seems to resemble the GART that sits between PC-style video cards and main memory. I don't know any details, but google quickly finds http://lwn.net/Articles/283798/ with a description of the initial GEM design. My main thought when looking over the DMM code was that this should not be tied too closely to a specific hardware, and GEM seems to be an existing abstraction that may fit what you need. Arnd -- 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
