[PATCH] octeon: fix unstable eMMC on ER-8

[Brian Norris]

Hi Yu,

On Fri, Sep 02, 2022 at 05:34:21PM -0600, Yu Zhao wrote:
> On Thu, Sep 1, 2022 at 12:54 AM Brian Norris
> <computersforpeace at gmail.com> wrote:
> > On Mon, Aug 01, 2022 at 01:50:36AM -0600, Yu Zhao via openwrt-devel wrote:
> > > This patch adds the DTS [8] from the stock firmware [2], and makes
> > > ER-8 use it. Interestingly, the only change in the device tree after
> > > this patch is the eMMC clock speed [9].
> >
> > This usually means it'd be a better idea to share the DTS source
> > (probably as a DTSI) and only override a single property.
> >
> > I haven't built a full octeon image yet nor grokked this target's
> > Makefile device definitions; what DTS are you replacing, anyway?
> 
> Currently the kernel uses DTS passed in from the bootloader. Please
> read the whole commit message :)

Sorry, I did miss that. So that means we don't necessarily have a good
starting point (like a per-SoC DTSI file).

> > Seems
> > very likely that you're repeating too much. At a minimum, I bet a large
> > chunk of this file can be replaced with just:
> >
> > #include "cn71xx.dtsi"
> 
> One of the reasons is that cn61xx is too different from cn71xx.

OK, I didn't do a proper diff -- in part because this DTS isn't really
in a readable form. If it's truly not related to SoCs for which we
already have DTSI files, then maybe the '#include' comments can be
ignored.

I still would recommend looking at the other comments about phandles and
DTS style.

> > >     # dtc -I fs -O dts /proc/device-tree/ -o ubnt_e200.dts
> 
> The second reason is that I consider this new DTS file "auto
> generated". IOW, it's not supposed to be edited.

What about the next person who finds a problem they need to fix?

> I see no need to study the DTS as long as it works.

This sounds like you're suggesting that decompiled assembly files are
also acceptable source material to merge into OpenWrt. Sure, they might
work, but they are not the preferred form to work with in the event they
need future fixes.

Anyway, I only showed up since I like to see stuff get reviewed and
merged (and you pinged the list for merging). I suspect anybody
reviewing your work for merging would have essentially the same sorts of
comments about how to write DTS files. But I'm not an OpenWrt committer,
and you're free to continue to wait around for one to respond, and see
what they say.

Regards,
Brian