linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Konrad Dybcio <konradybcio@gmail.com>
To: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Will Deacon <will@kernel.org>,
	skrzynka@konradybcio.pl, Robin Murphy <robin.murphy@arm.com>,
	Joerg Roedel <joro@8bytes.org>, Rob Herring <robh+dt@kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	iommu@lists.linux-foundation.org,
	DTML <devicetree@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	jcrouse@codeaurora.org, John Stultz <john.stultz@linaro.org>
Subject: Re: [PATCH 1/1] iommu/arm-smmu: Implement qcom,skip-init
Date: Tue, 21 Jul 2020 17:04:11 +0200	[thread overview]
Message-ID: <CAMS8qEWO-1mNd12Zs-2WogCrgNF5=6RkF=Z1pTeOZxSuKjx+qg@mail.gmail.com> (raw)
In-Reply-To: <20200705033511.GR388985@builder.lan>

So.. is this a no-no?

I of course would like to omit this entirely, but SMMUs on sdm630 and
friends are REALLY picky.. What seems to happen is that when the
driver tries to do things the "standard" way, hypervisor decides to
hang the platform or force a reboot. Not very usable.


This thing is needed for the platform to even boot properly and one
more [1] is required to make mdss work with video mode panels (the
fact that CMD-mode panels work is kinda hilarious to me).

To be honest, there are even more qcom quirks (of which at least
qcom,dynamic and qcom-use-3-lvl-tables are used on 630).. [2]

Looking forward to your answers and possibly better solutions.

[1] https://github.com/konradybcio/linux/commit/83ac38af259968f92b6a8b7eab90096c78469f87
[2] https://github.com/sonyxperiadev/kernel/blob/aosp/LA.UM.7.1.r1/drivers/iommu/arm-smmu.c#L404-L415

Regards
Konrad

  reply	other threads:[~2020-07-21 15:04 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-04 12:28 [PATCH 1/1] iommu/arm-smmu: Implement qcom,skip-init Konrad Dybcio
2020-07-04 13:09 ` Will Deacon
2020-07-04 13:20   ` Konrad Dybcio
2020-07-05  3:35   ` Bjorn Andersson
2020-07-21 15:04     ` Konrad Dybcio [this message]
2020-07-21 15:44       ` Jordan Crouse
2020-07-21 16:20         ` Konrad Dybcio
2020-07-21 23:56           ` Bjorn Andersson
2020-07-22 20:11             ` Konrad Dybcio
2020-07-31  5:48               ` Bjorn Andersson
2020-08-03 23:57                 ` Konrad Dybcio

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='CAMS8qEWO-1mNd12Zs-2WogCrgNF5=6RkF=Z1pTeOZxSuKjx+qg@mail.gmail.com' \
    --to=konradybcio@gmail.com \
    --cc=bjorn.andersson@linaro.org \
    --cc=devicetree@vger.kernel.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=jcrouse@codeaurora.org \
    --cc=john.stultz@linaro.org \
    --cc=joro@8bytes.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=robh+dt@kernel.org \
    --cc=robin.murphy@arm.com \
    --cc=skrzynka@konradybcio.pl \
    --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).