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Message-ID: <f638e848-36c5-4cea-c2c8-841a003b1863@quicinc.com>
Date: Thu, 14 Mar 2024 16:39:26 -0700
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Subject: Re: [RESEND v4 3/3] arm64: dts: qcom: sc7280: Add power-domains for
 cpuidle states
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To: Doug Anderson <dianders@chromium.org>,
        Maulik Shah
	<quic_mkshah@quicinc.com>
CC: <andersson@kernel.org>, <ulf.hansson@linaro.org>, <swboyd@chromium.org>,
        <wingers@google.com>, <daniel.lezcano@linaro.org>, <rafael@kernel.org>,
        <linux-arm-msm@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-pm@vger.kernel.org>, <sudeep.holla@arm.com>,
        <jwerner@chromium.org>, <quic_lsrao@quicinc.com>,
        <quic_rjendra@quicinc.com>, <devicetree@vger.kernel.org>,
        Jessica Zhang <quic_jesszhan@quicinc.com>,
        "Rob
 Clark" <robdclark@chromium.org>
References: <20230703085555.30285-1-quic_mkshah@quicinc.com>
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From: Abhinav Kumar <quic_abhinavk@quicinc.com>
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Hi Doug

On 3/14/2024 4:20 PM, Doug Anderson wrote:
> Hi,
> 
> On Mon, Jul 3, 2023 at 1:56 AM Maulik Shah <quic_mkshah@quicinc.com> wrote:
>>
>> Add power-domains for cpuidle states to use psci os-initiated idle states.
>>
>> Cc: devicetree@vger.kernel.org
>> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
>> Signed-off-by: Maulik Shah <quic_mkshah@quicinc.com>
>> ---
>>   arch/arm64/boot/dts/qcom/sc7280.dtsi | 98 +++++++++++++++++++++-------
>>   1 file changed, 73 insertions(+), 25 deletions(-)
> 
> FWIW, I dug up an old sc7280-herobrine board to test some other change
> and found it no longer booted. :( I bisected it and this is the change
> that breaks it. Specifically, I can make mainline boot with:
> 
> git revert --no-edit db5d137e81bc # arm64: dts: qcom: sc7280: Update
> domain-idle-states for cluster sleep
> git revert --no-edit 7925ca85e956 # arm64: dts: qcom: sc7280: Add
> power-domains for cpuidle states
> 

We noticed that some variants of sc7280 herobrine boards didnt boot but 
some did atleast till linux 6.8 rc-6. I have not tested linux 6.9 rc-1 yet.

We did not narrow down which change broke some of the boards, I can go 
back and confirm if its this one next week.

> (I get an ath11k crash after that, but that's easy to hack out since I
> don't need WiFi)
> 

hmm, wifi worked alright on 6.8 rc-6 for us.

> I suppose the two options here are to either:
> 
> 1. Track the problem down and figure out why the breaks boot and then
> fix it. I'm personally not going to track this down, but if someone
> wants me to test a patch I can do that.
> 

Can Maulik help us do that?

> 2. Delete all the herobrine dts files.
> 
> So far we've been keeping the herobrine dts files alive because I
> thought some graphics folks (Rob, Abhinav, Jessica, for instance) were
> still using it. ...but Rob says he hasn't booted his in a while. No
> idea if Abhinav and Jessica are using theirs. Any opinions? Is
> herobrine hardware support near and dear to anyone these days?
> 

Yes, so we have been using sc7280 herobrine devices even till the last 
cycle and quite a bit of feature development was actually done on that.

It was the only device having eDP other than sc8280xp till x1e80100 
landed last cycle.

I do want to start using sc8280xp as well because from the experience we 
got, it has more visibility in terms of users. So that will address my 
eDP concern.

But, the nice thing about chromebooks is we really like to use them for 
IGT development / CI debug as CrOS provides a nice environment to 
cros-deploy IGT.

We can continue to use sc7180 for IGT development but if we want to 
debug issues with eDP + IGT, sc7280 is a really useful platform for that.

sc8280xp or x1e80100 is not a CrOS supported device. So we will have to 
develop and test IGT directly on the device (which is a bit of a pain) 
unless someone has a better way of "cross-compilation" for IGT on 
non-CrOS images.


> 
> -Doug