Re: [RFC 0/3] clk: imx: Implement blk-ctl driver for i.MX8MN

From: Abel Vesa
Date: Sun Oct 25 2020 - 08:05:51 EST


On 20-10-24 16:03:17, Adam Ford wrote:
> On Sat, Oct 24, 2020 at 3:23 PM Abel Vesa <abel.vesa@xxxxxxx> wrote:
> >
> > On 20-10-24 11:20:12, Adam Ford wrote:
> > > There are some less-documented registers which control clocks and
> > > resets for the multimedia block which controls the LCDIF, ISI, MIPI
> > > CSI, and MIPI DSI.
> > >
> > > The i.Mx8M Nano appears to have a subset of the i.MX8MP registers with
> > > a couple shared registers with the i.MX8MM. This series builds on the
> > > series that have been submitted for both of those other two platforms.
> > >
> > > This is an RFC because when enabling the corresponding DTS node, the
> > > system freezes on power on. There are a couple of clocks that don't
> > > correspond to either the imx8mp nor the imx8mm, so I might have something
> > > wrong, and I was hoping for some constructive feedback in order to get
> > > the imx8m Nano to a similar point of the Mini and Plus.
> > >
> >
> > Thanks for the effort.
>
> Sure thing!
>
> >
> > I'm assuming this relies on the following patchset, right ?
> > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2020%2F10%2F24%2F139&amp;data=04%7C01%7Cabel.vesa%40nxp.com%7C00007fdffcb44af4bbe808d8786044cf%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637391702150893977%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=RIdR4O2Qx3q7ovfAO7O3kc%2BpXXMPzLQJWPoUAH305%2Bs%3D&amp;reserved=0
> Abell,
>
> Your link points right back to this e-mail. ;-)

Sorry about that. Was kinda late here yesterday.

>
> I based this work off:
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.spinics.net%2Flists%2Farm-kernel%2Fmsg843906.html&amp;data=04%7C01%7Cabel.vesa%40nxp.com%7C00007fdffcb44af4bbe808d8786044cf%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637391702150893977%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=6B3UHZNULMB%2FtMzdWHckIOFlqFxEYwYdQclzqDtJ%2FNQ%3D&amp;reserved=0 from Marek
> which I beleive is based on
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.spinics.net%2Flists%2Farm-kernel%2Fmsg836165.html&amp;data=04%7C01%7Cabel.vesa%40nxp.com%7C00007fdffcb44af4bbe808d8786044cf%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637391702150893977%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=I%2FfgIjzqwnjuSGOPfVKa%2BPbx950Be008sOon%2FDwSO1o%3D&amp;reserved=0 from you.
>
> I also have a GPC patch series located:
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.spinics.net%2Flists%2Farm-kernel%2Fmsg847925.html&amp;data=04%7C01%7Cabel.vesa%40nxp.com%7C00007fdffcb44af4bbe808d8786044cf%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637391702150893977%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=dF%2Bgth7dwopoB2rvQ8IqspTZ7kWxvMYGS0dY%2F0gWgXE%3D&amp;reserved=0
>
> Together, both the GPC and the clk-blk driver should be able to pull
> the multimedia block out of reset. Currently, the GPC can handle the
> USB OTG and the GPU, but the LCDIF and MIPI DSI appear to be gated by
> the clock block
>
> My original patch RFC didn't include the imx8mn node, because it
> hangs, but the node I added looks like:
>
> media_blk_ctl: clock-controller@32e28000 {
> compatible = "fsl,imx8mn-media-blk-ctl", "syscon";
> reg = <0x32e28000 0x1000>;
> #clock-cells = <1>;
> #reset-cells = <1>;
> };
>
> I was hoping you might have some feedback on the 8mn clk-blk driver
> since you did the 8mp clk-blk drive and they appear to be very
> similar.
>

I'll do you one better still. I'll apply the patch in my tree and give it
a test tomorrow morning.

> adam
>
>
> >
> > > Adam Ford (3):
> > > dt-bindings: clock: imx8mn: Add media blk_ctl clock IDs
> > > dt-bindings: reset: imx8mn: Add media blk_ctl reset IDs
> > > clk: imx: Add blk-ctl driver for i.MX8MN
> > >
> > > drivers/clk/imx/clk-blk-ctl-imx8mn.c | 80 ++++++++++++++++++++++++
> > > include/dt-bindings/clock/imx8mn-clock.h | 11 ++++
> > > include/dt-bindings/reset/imx8mn-reset.h | 22 +++++++
> > > 3 files changed, 113 insertions(+)
> > > create mode 100644 drivers/clk/imx/clk-blk-ctl-imx8mn.c
> > > create mode 100644 include/dt-bindings/reset/imx8mn-reset.h
> > >
> > > --
> > > 2.25.1
> > >