On 02/25/2013 07:28 AM, Peter De Schrijver wrote: > On Sat, Feb 23, 2013 at 05:31:17AM +0100, Stephen Warren wrote: ... >> Peter, can you confirm exactly which [PMC] HW versions, if any, are 100% >> backwards-compatible? >> > > The major difference between the PMCs are the powerdomain IDs. The Tegra30 IDs > are a strict superset of the Tegra20 IDs, but the Tegra114 IDs are not. There > are differences in the CPU domains and 3D. The CPU domains aren't a problem I > think because we won't powergate those domains directly using the PMC. We > always program the flowcontroller to do the powergating on WFI. 3D is a > different story however. We do powergate 3D under software control and the > sequencing is different between Tegra30 and Tegra114. Also Tegra30 has 2 > domains for 3D while Tegra114 has only 1. Then of course Tegra114 lacks the > SATA and PCIe domains because those features are missing compared to Tegra30. > But the IDs haven't been reused. All in all I think it's best to explicitly > require the driver to support the various SoCs. That does sound like a good idea; a separate compatible value for each SoC. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
