Re: [PATCH 0/8] Tegra124 EMC (external memory controller) support

From: Thierry Reding
Date: Tue Aug 26 2014 - 03:48:01 EST


On Tue, Aug 26, 2014 at 10:42:21AM +0300, Mikko Perttunen wrote:
> On 25/08/14 20:40, Stephen Warren wrote:
> >On 07/11/2014 08:18 AM, Mikko Perttunen wrote:
> >>Hi everyone,
> >>
> >>this series adds support for the EMC (external memory controller) clock
> >>in the Tegra124 system-on-chip. The series has been tested on Jetson TK1.
> >>
> >>The first two patches remove the old "emc_mux" and "emc" clocks from the
> >>clock tree and the device tree bindings. This is, of course, not
> >>backwards
> >>compatible, but as these clocks have never been useful for anything
> >>(apart from maybe reading the boot rate of the EMC clock). If this is
> >>still
> >>not acceptable, the second patch can be dropped.
> >...
> >
> >Mikko, this series had some comments, especially on the DT binding
> >(patch 5/8) and how the MC/EMC drivers interact. Is there an updated
> >version of the series? Or, is the series replaced by Tomeu Vizoso's work?
>
> Yes, I have a v2 with these comments addressed. One concern, though, is the
> part writing to CLK_SOURCE_EMC. If some other driver also wants to read this
> register (MC, likely), we might need to have an API for it in the CAR
> driver. On the other hand, maybe not, since it's only one register. Thierry?

I don't think any of these drivers should directly access registers that
aren't in the memory region that they've claimed. If they need to access
functionality provided by some other driver then they should do so via a
custom API.

Thierry

Attachment: pgpT3FCnxTnMS.pgp
Description: PGP signature