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Message-ID: <1cbd12ad-4147-5d97-ef7f-4104b630244b@linaro.org>
Date:   Tue, 17 May 2022 15:56:06 -0500
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Subject: Re: [PATCH] arm64: dts: qcom: sc7180: Remove ipa_fw_mem node on
 trogdor
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To:     Stephen Boyd <swboyd@chromium.org>, Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>
Cc:     linux-kernel@vger.kernel.org, patches@lists.linux.dev,
        linux-arm-msm@vger.kernel.org, Matthias Kaehlcke <mka@chromium.org>
References: <20220517193307.3034602-1-swboyd@chromium.org>
 <ceb32b66-1341-d54f-a60a-5c342119c784@linaro.org>
 <CAE-0n50rUW7Lqk4CwfSUgKYEJzwjXuVohAnbj9uKA=kEkXikyw@mail.gmail.com>
From:   Alex Elder <elder@linaro.org>
In-Reply-To: <CAE-0n50rUW7Lqk4CwfSUgKYEJzwjXuVohAnbj9uKA=kEkXikyw@mail.gmail.com>
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On 5/17/22 3:06 PM, Stephen Boyd wrote:
> Quoting Alex Elder (2022-05-17 12:51:34)
>> On 5/17/22 2:33 PM, Stephen Boyd wrote:
>>> We don't use this carveout on trogdor boards, and having it defined in
>>> the sc7180 SoC file causes an overlap message to be printed at boot.
>>>
>>>    OF: reserved mem: OVERLAP DETECTED!
>>>    memory@86000000 (0x0000000086000000--0x000000008ec00000) overlaps with memory@8b700000 (0x000000008b700000--0x000000008b710000)
>>>
>>> Delete the node in the trogdor dtsi file to fix the overlap problem and
>>> remove the error message.'
>>
>> Is the mpss_mem node (which defines 0x86000000-0x8ec00000) correct?
> 
> I think it is. Modem is working for me.
> 
>>
>> You're right, we don't use that memory on Chrome OS, but I just
>> wondered whether the other node might also have a problem.
> 
> What sort of problem are you thinking about?

At some point in the past I think some of these carved out
areas got updated (perhaps on sdm845?).  I.e. they were
wrong, and got corrected later.  Some things worked despite
that.  So the problem, for example, might be that the
mpss region is bigger than it needs to be.

I don't *assume* there's a problem, I was just asking,
and maybe Bjorn or someone else can verify what's right.

I'm done for the day right now; otherwise I'd spend a
little more time trying to track the information down
myself...

					-Alex


>>
>> I don't actually know...  Bjorn, do you?
>>