[PATCH 1/4] ARM: tegra: pmc: convert PMC driver to support DT only

Joseph Lo josephl at nvidia.com
Mon Feb 25 21:27:42 EST 2013


On Mon, 2013-02-25 at 23:43 +0800, Stephen Warren wrote:
> 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.

OK. Will add another patch to fix the PMC compatibility in Tegra30 and
Tegra114 dts file. And also in the DT match table of PMC driver.

Thanks,
Joseph




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