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Date: Thu, 19 Sep 2024 12:07:29 +0200
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Subject: Re: [RFC PATCH 00/11] Affirm SMMU coherent pagetable walker
 capability on RPMh SoCs
To: Luca Weiss <luca.weiss@fairphone.com>,
 Konrad Dybcio <konradybcio@kernel.org>,
 Bjorn Andersson <andersson@kernel.org>, Rob Herring <robh@kernel.org>,
 Krzysztof Kozlowski <krzk+dt@kernel.org>, Conor Dooley
 <conor+dt@kernel.org>, cros-qcom-dts-watchers@chromium.org
Cc: Marijn Suijten <marijn.suijten@somainline.org>,
 linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
 linux-kernel@vger.kernel.org, Konrad Dybcio <quic_kdybcio@quicinc.com>
References: <20240919-topic-apps_smmu_coherent-v1-0-5b3a8662403d@quicinc.com>
 <D4A2FKPTXHS5.3AHU7ZEKFVMGG@fairphone.com>
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From: Konrad Dybcio <konradybcio@kernel.org>
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On 19.09.2024 9:00 AM, Luca Weiss wrote:
> On Thu Sep 19, 2024 at 12:57 AM CEST, Konrad Dybcio wrote:
>> I only read back the SMMU config on X1E & 7280, but I have it on good
>> authority that this concerns all RPMh SoCs. Sending as RFC just in case.
>>
>> Lacking coherency can hurt performance, but claiming coherency where it's
>> absent would lead to a kaboom.
> 
> Hi Konrad!
> 
> You want people with the affected SoCs to test this I imagine?

Yeah, would be nice to confirm

> 
> Just boot it and see if it doesn't implode, or do you have any more
> elaborate test plan for this?

No, booting should be enough of a test

Konrad