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Date: Thu, 22 Jan 2026 12:12:53 +0000
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Subject: Re: [PATCH] iommu/arm-smmu-qcom: do not register driver in probe()
To: Danilo Krummrich <dakr@kernel.org>, Ioana Ciornei <ioana.ciornei@nxp.com>
Cc: gregkh@linuxfoundation.org, rafael@kernel.org, broonie@kernel.org,
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References: <20260121141215.29658-1-dakr@kernel.org>
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From: Robin Murphy <robin.murphy@arm.com>
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On 2026-01-22 11:52 am, Danilo Krummrich wrote:
> On Thu Jan 22, 2026 at 10:21 AM CET, Ioana Ciornei wrote:
>> The boot lockup was visible also on the NXP LX2160ARDB. This patch fixes
>> it.
> 
> Interesting, this means that qcom_smmu_impl_init() must be called on this
> machine, is this expected?

Yup, same as on the Juno boards and probably others - an Arm SMMU is 
present, which means if ARM_SMMU_QCOM is enabled then 
arm_smmu_impl_init() is going to offer it to ask "hey, is this one of 
yours that you might want to do something with based on your extensive 
and complicated match list that we don't want to maintain in the common 
impl code?", wherein qcom_smmu_impl_init() *should* return without doing 
anything at all as it's not a match...

Cheers,
Robin.

> 
>> Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> #LX2160ARDB
> 
> Thanks for testing!