Am Montag, dem 17.05.2021 um 10:23 -0300 schrieb Ezequiel Garcia:

On Mon, 2021-05-17 at 12:52 +0200, Lucas Stach wrote:

quoted

Hi Ezequiel,

Am Sonntag, dem 16.05.2021 um 19:40 -0300 schrieb Ezequiel Garcia:

quoted

Hi Lucas,

On Fri, 2021-04-16 at 12:54 +0200, Lucas Stach wrote:

quoted

Am Mittwoch, dem 07.04.2021 um 09:35 +0200 schrieb Benjamin Gaignard:

quoted

In order to be able to share the control hardware block between
VPUs use a syscon instead a ioremap it in the driver.
To keep the compatibility with older DT if 'nxp,imx8mq-vpu-ctrl'
phandle is not found look at 'ctrl' reg-name.
With the method it becomes useless to provide a list of register
names so remove it.

Sorry for putting a spoke in the wheel after many iterations of the
series.

We just discussed a way forward on how to handle the clocks and resets
provided by the blkctl block on i.MX8MM and later and it seems there is
a consensus on trying to provide virtual power domains from a blkctl
driver, controlling clocks and resets for the devices in the power
domain. I would like to avoid introducing yet another way of handling
the blkctl and thus would like to align the i.MX8MQ VPU blkctl with
what we are planning to do on the later chip generations.

CC'ing Jacky Bai and Peng Fan from NXP, as they were going to give this
virtual power domain thing a shot.

It seems the i.MX8MM BLK-CTL series are moving forward:

https://patchwork.kernel.org/project/linux-arm-kernel/list/?series=479175

... but I'm unable to wrap my head around how this affects the
devicetree VPU modelling for i.MX8MQ (and also i.MX8MM, i.MX8MP, ...).

For the i.MX8MQ we want to have the same virtual power-domains provided
by a BLK-CTRL driver for the VPUs, as on i.MX8MM. This way we should be
able to use the same DT bindings for the VPUs on i.MX8MQ and i.MX8MM,
even though the SoC integration with the blk-ctrl is a little
different.

AFAICS, there's not support for i.MX8MP VPU power domains. I suppose
we should make sure we'll be able to cover those as well.

Will i.MX8MP need its own driver as well?

quoted

I haven't looked too closely at the 8MP VPU subsystem yet, but I expect
it to be slightly different again so it will need changes to the blk-
ctrl driver. But that's the whole point of this virtual power domain
exercise: abstract away the SoC specific things in the blk-ctrl driver,
so the VPU driver doesn't need to care about them.

Regards,
Lucas


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel