Messages in this thread | | | From | Dmitry Baryshkov <> | Date | Mon, 30 Aug 2021 04:17:32 +0300 | Subject | Re: [PATCH 2/3] drm/msm/dsi: Use "ref" fw clock instead of global name for VCO parent |
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On Mon, 30 Aug 2021 at 00:53, Marijn Suijten <marijn.suijten@somainline.org> wrote: > > Hi Dmitry, > > On 8/29/21 10:39 PM, Dmitry Baryshkov wrote: > > Hi, > > > > On Sun, 29 Aug 2021 at 23:30, Marijn Suijten > > <marijn.suijten@somainline.org> wrote: > >> > >> All DSI PHY/PLL drivers were referencing their VCO parent clock by a > >> global name, most of which don't exist or have been renamed. These > >> clock drivers seem to function fine without that except the 14nm driver > >> for the sdm6xx [1]. > >> > >> At the same time all DTs provide a "ref" clock as per the requirements > >> of dsi-phy-common.yaml, but the clock is never used. This patchset puts > >> that clock to use without relying on a global clock name, so that all > >> dependencies are explicitly defined in DT (the firmware) in the end. > > > > msm8974 (28nm-hpm) does not define the "ref" clock. So you'd have to: > > 1) add ref clock to the dtsi (should come in a separate patch). > > > Thanks for double-checking and noticing this! I've queued up this patch > for v2. > > > 2) add .name = "xo" as a fallback to the 28nm driver (to be compatible > > with older devices) > > > Are there msm8974 devices out there that might upgrade kernels, but not > firmware (DT)? On other boards (sdm630) I'm removing these from various > drivers as to not have any possibility of relying on global names, in > favour of having the clock dependencies fully specified in the DT.
IIUC it is a general policy of trying to be (somewhat) backwards-compatible. For example because your dts might come from a different source/be a part of different build process/etc.
> > > Other than that this looks good to me. > > > Any r-b/a-b/t-b I can pick up for the next round?
Let's get those issues fixed and I'll respond with R-B tags
-- With best wishes Dmitry
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