From: Rob Clark <robdclark@gmail.com>
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: dri-devel <dri-devel@lists.freedesktop.org>,
linux-arm-msm <linux-arm-msm@vger.kernel.org>,
freedreno <freedreno@lists.freedesktop.org>,
aarch64-laptops@lists.linaro.org,
Rob Clark <robdclark@chromium.org>,
Ard Biesheuvel <ard.biesheuvel@linaro.org>,
Catalin Marinas <catalin.marinas@arm.com>,
"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
<devicetree@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>,
Julien Thierry <julien.thierry@arm.com>,
"open list:EXTENSIBLE FIRMWARE INTERFACE (EFI)"
<linux-efi@vger.kernel.org>,
open list <linux-kernel@vger.kernel.org>,
Lukas Wunner <lukas@wunner.de>,
Steve Capper <steve.capper@arm.com>,
Will Deacon <will@kernel.org>
Subject: Re: [PATCH 0/4] drm+dt+efi: support devices with multiple possible panels
Date: Sun, 30 Jun 2019 14:05:21 -0700 [thread overview]
Message-ID: <CAF6AEGvA-wVyC4jJC-nZU-pdVH=KYtye9twDgup-Nq0C_+wtvQ@mail.gmail.com> (raw)
In-Reply-To: <20190630204723.GH7043@pendragon.ideasonboard.com>
On Sun, Jun 30, 2019 at 1:47 PM Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hi Rob,
>
> Thank you for the patch.
>
> On Sun, Jun 30, 2019 at 01:36:04PM -0700, Rob Clark wrote:
> > From: Rob Clark <robdclark@chromium.org>
> >
> > Now that we can deal gracefully with bootloader (firmware) initialized
> > display on aarch64 laptops[1], the next step is to deal with the fact
> > that the same model of laptop can have one of multiple different panels.
> > (For the yoga c630 that I have, I know of at least two possible panels,
> > there might be a third.)
>
> I have to ask the obvious question: why doesn't the boot loader just
> pass a correct DT to Linux ? There's no point in passing a list of
> panels that are not there, this seems quite a big hack to me. A proper
> boot loader should construct the DT based on hardware detection.
Hi Laurent,
Actually the bootloader on these devices is passing *no* dt (they boot
ACPI, we are loading dtb from grub currently)
I think normally a device built w/ dt in mind would populate
/chosen/panel-id directly (rather than the way it is currently
populated based on reading an efi variable prior to ExitBootServices).
But that is considerably easier ask than having it re-write of_graph
bindings. Either way, we aren't in control of the bootloader on these
devices, so it is a matter of coming up with something that works on
actual hw that we don't like rather than idealized hw that we don't
have ;-)
BR,
-R
next prev parent reply other threads:[~2019-06-30 21:05 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-30 20:36 [PATCH 0/4] drm+dt+efi: support devices with multiple possible panels Rob Clark
2019-06-30 20:36 ` [PATCH 2/4] efi/libstub: detect panel-id Rob Clark
2019-07-02 20:26 ` Ard Biesheuvel
2019-07-02 20:35 ` Ard Biesheuvel
2019-07-02 21:01 ` Rob Clark
2019-07-02 21:53 ` Ard Biesheuvel
2019-07-02 22:36 ` Rob Clark
2019-07-02 21:59 ` Leif Lindholm
2019-07-02 22:48 ` Rob Clark
2019-07-03 16:33 ` Leif Lindholm
2019-07-03 17:41 ` Rob Clark
2019-07-03 17:54 ` Ard Biesheuvel
2019-06-30 20:47 ` [PATCH 0/4] drm+dt+efi: support devices with multiple possible panels Laurent Pinchart
2019-06-30 21:05 ` Rob Clark [this message]
2019-06-30 21:15 ` Laurent Pinchart
2019-06-30 21:35 ` Rob Clark
2019-07-02 12:50 ` Rob Clark
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAF6AEGvA-wVyC4jJC-nZU-pdVH=KYtye9twDgup-Nq0C_+wtvQ@mail.gmail.com' \
--to=robdclark@gmail.com \
--cc=aarch64-laptops@lists.linaro.org \
--cc=ard.biesheuvel@linaro.org \
--cc=catalin.marinas@arm.com \
--cc=devicetree@vger.kernel.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=freedreno@lists.freedesktop.org \
--cc=julien.thierry@arm.com \
--cc=laurent.pinchart@ideasonboard.com \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lukas@wunner.de \
--cc=mingo@kernel.org \
--cc=robdclark@chromium.org \
--cc=steve.capper@arm.com \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).