Re: [PATCH 2/6] arm64: dts: qcom: sm8250: add apps_smmu node

[Bjorn Andersson]

On Mon 25 May 04:53 PDT 2020, Jonathan Marek wrote:
[..]
> I guess the commit message is ambiguous, that's not what I meant. Is "Now
> that the kernel initializes the iommu, the bypass mappings set by the
> bootloader are cleared. Adding the iommus property is required so that new
> mappings are created for UFS." better?
> 

This looks better, but it's actually not a bypass mapping that we
inherit from the bootloader, it's the stream mapping pointing to a
disabled (~ARM_SMMU_SCTLR_M) context bank. So when we wipe the stream
mappings we will fault on the unmatched stream - which secure world
"handles" for us...

As such, I think you should replace "bypass" with "stream".

Regards,
Bjorn