Re: [PATCH] arm64: dts: sdm845: Add iommus property to qup1

Bjorn Andersson
2019-06-04T22:56:33Z

On Tue 04 Jun 15:48 PDT 2019, Doug Anderson wrote:

> Hi,
>
> On Tue, Jun 4, 2019 at 3:37 PM Bjorn Andersson
> <bjorn.andersson@linaro.org> wrote:
> >
> > On Tue 04 Jun 15:29 PDT 2019, Stephen Boyd wrote:
> >
> > > The SMMU that sits in front of the QUP needs to be programmed properly
> > > so that the i2c geni driver can allocate DMA descriptors. Failure to do
> > > this leads to faults when using devices such as an i2c touchscreen where
> > > the transaction is larger than 32 bytes and we use a DMA buffer.
> > >
> >
> > I'm pretty sure I've run into this problem, but before we marked the
> > smmu bypass_disable and as such didn't get the fault, thanks.
> >
> > > arm-smmu 15000000.iommu: Unexpected global fault, this could be serious
> > > arm-smmu 15000000.iommu: GFSR 0x00000002, GFSYNR0 0x00000002, GFSYNR1 0x000006c0, GFSYNR2 0x00000000
> > >
> > > Add the right SID and mask so this works.
> > >
> > > Cc: Sibi Sankar <sibis@codeaurora.org>
> > > Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> > > ---
> > > arch/arm64/boot/dts/qcom/sdm845.dtsi | 1 +
> > > 1 file changed, 1 insertion(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/qcom/sdm845.dtsi b/arch/arm64/boot/dts/qcom/sdm845.dtsi
> > > index fcb93300ca62..2e57e861e17c 100644
> > > --- a/arch/arm64/boot/dts/qcom/sdm845.dtsi
> > > +++ b/arch/arm64/boot/dts/qcom/sdm845.dtsi
> > > @@ -900,6 +900,7 @@
> > > #address-cells = <2>;
> > > #size-cells = <2>;
> > > ranges;
> > > + iommus = <&apps_smmu 0x6c0 0x3>;
> >
> > According to the docs this stream belongs to TZ, the HLOS stream should
> > be 0x6c3.
>
> Since you've already got the docs in front of you, how about looking
> up the value for qup0 so we can fix both of 'em?
>

Good thinking. QUP_1 is at stream 0x3.

Regards,
Bjorn