Re: [PATCH 0/2] iommu/arm-smmu: Add an optional "input-address-size" property

[Nicolin Chen]

On Fri, Oct 11, 2019 at 10:16:28AM +0100, Robin Murphy wrote:
> On 2019-10-11 4:46 am, Nicolin Chen wrote:
> > This series of patches add an optional DT property to allow an SoC to
> > specify how many bits being physically connected to its SMMU instance,
> > depending on the SoC design.
> 
> This has come up before, and it doesn't work in general because a single
> SMMU instance can have many master interfaces, with potentially different
> sizes of address bus wired up to each. It's also a conceptually-wrong
> approach anyway, since this isn't a property of the SMMU; it's a property of
> the interconnect(s) upstream of the SMMU.
> 
> IIRC you were working on Tegra - if so, Thierry already has a plan, see this
> thread:
> https://lore.kernel.org/linux-arm-kernel/20190930133510.GA1904140@ulmo/

Thanks for the reply and link!