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Message-ID: <d80ece40-fdd7-f304-3989-47ae152d5ac9@linaro.org>
Date:   Wed, 13 Apr 2022 16:02:00 -0500
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Subject: Re: [PATCH 1/2] interconnect: qcom: sc7180: Drop IP0 interconnects
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To:     Doug Anderson <dianders@chromium.org>,
        Stephen Boyd <swboyd@chromium.org>
Cc:     Georgi Djakov <djakov@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, patches@lists.linux.dev,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>,
        Linux PM <linux-pm@vger.kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Taniya Das <quic_tdas@quicinc.com>,
        Mike Tipton <quic_mdtipton@quicinc.com>
References: <20220412220033.1273607-1-swboyd@chromium.org>
 <20220412220033.1273607-2-swboyd@chromium.org>
 <CAD=FV=UFbOhs0ggxDbVwKM_8x=ELT85zFd-Wk6dJ_M+Awz+Pxw@mail.gmail.com>
From:   Alex Elder <elder@linaro.org>
In-Reply-To: <CAD=FV=UFbOhs0ggxDbVwKM_8x=ELT85zFd-Wk6dJ_M+Awz+Pxw@mail.gmail.com>
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On 4/13/22 3:55 PM, Doug Anderson wrote:
> Hi,
> 
> On Tue, Apr 12, 2022 at 4:20 PM Stephen Boyd <swboyd@chromium.org> wrote:
>>
>> @@ -519,8 +500,6 @@ static const struct of_device_id qnoc_of_match[] = {
>>            .data = &sc7180_dc_noc},
>>          { .compatible = "qcom,sc7180-gem-noc",
>>            .data = &sc7180_gem_noc},
>> -       { .compatible = "qcom,sc7180-ipa-virt",
>> -         .data = &sc7180_ipa_virt},
>>          { .compatible = "qcom,sc7180-mc-virt",
>>            .data = &sc7180_mc_virt},
>>          { .compatible = "qcom,sc7180-mmss-noc",
> 
> I have no objection to ${SUBJECT} change landing and based on all your
> research and Alex's review/testing I think it's good to go.
> 
> However, now that you're removed the driver that cared about
> "qcom,sc7180-ipa-virt", should we also be removing it from the
> `bindings/interconnect/qcom,rpmh.yaml` file and the `sc7180.dtsi`
> file? I think that removing it from _either_ the driver (like your
> patch here does) _or_ the sc7180.dtsi file would fix the bug, right?
> ...and then removing it from the yaml would just be cleanup...

That's a good point, I hadn't thought about that but you're right.

I think we were too pleased about identifying the problem and
proving it could happen (and cause a crash), so we didn't think
hard enough about this other piece.

Stephen, I think you should re-spin the series and add the
proper change to the binding.  You can keep the tags I gave
before.

I've got a note to follow up with similar changes to other
platforms where the interconnect driver includes resource "IP0"
and will plan to do what Doug suggests there too.

					-Alex

> -Doug