On 3/15/2013 8:21 AM, Marek Szyprowski wrote:
This scheme of associating devices with CMA regions by base does not work if you want to let CMA figure out where to place the region (base = 0). Can we use the name to associate the device with the region? I had been working on something similar internally and that was the only solution I had come up with to associate arbitrary CMA nodes with devices.
Right, support for base = 0 requires different handling, but I thought that if we use the device tree approach, the designer already knows the complete memory configuration, so providing the correct base address is not that hard.
Not necessarily. The sizes of and number of regions may change depending on use cases. It's much easier to let Linux figure out where to place the regions vs. having to manually place everything each time. (This also gets into the fact that some of the way we use CMA is a 'grey' area that isn't actually hardware related)
Thanks, Laura