Re: [PATCH 01/14] staging: media: tegra-vde: Support BSEV clock and reset

[Thierry Reding <thierry.reding@gmail.com>]

[-- Attachment #1.1: Type: text/plain, Size: 1181 bytes --]

On Mon, Aug 13, 2018 at 06:09:46PM +0300, Dmitry Osipenko wrote:
> On Monday, 13 August 2018 17:50:14 MSK Thierry Reding wrote:
> > From: Thierry Reding <treding@nvidia.com>
> > 
> > The BSEV clock has a separate gate bit and can not be assumed to be
> > always enabled. Add explicit handling for the BSEV clock and reset.
> > 
> > This fixes an issue on Tegra124 where the BSEV clock is not enabled
> > by default and therefore accessing the BSEV registers will hang the
> > CPU if the BSEV clock is not enabled and the reset not deasserted.
> > 
> > Signed-off-by: Thierry Reding <treding@nvidia.com>
> > ---
> 
> Are you sure that BSEV clock is really needed for T20/30? I've tried already 
> to disable the clock explicitly and everything kept working, though I'll try 
> again.

I think you're right that these aren't strictly required for VDE to work
on Tegra20 and Tegra30. However, the BSEV clock and reset do exist on
those platforms, so I didn't see a reason why they shouldn't be handled
uniformly across all generations.

> The device-tree changes should be reflected in the binding documentation.

Indeed, I forgot to update that.

Thierry

[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

[-- Attachment #2: Type: text/plain, Size: 169 bytes --]

_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel