On Mon, 17 Jul 2023 at 16:15, Stephan Gerhold <stephan@xxxxxxxxxxx> wrote:
>
> On Mon, Jul 17, 2023 at 04:02:35PM +0530, Bhupesh Sharma wrote:
> > Add the Embedded USB Debugger(EUD) device tree node for
> > SM6115 / SM4250 SoC.
> >
> > The node contains EUD base register region, EUD mode manager
> > register region and TCSR Base register region along with the
> > interrupt entry.
> >
> > [...]
> >
> > Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
> > Signed-off-by: Bhupesh Sharma <bhupesh.sharma@xxxxxxxxxx>
> > ---
> > arch/arm64/boot/dts/qcom/sm6115.dtsi | 50 ++++++++++++++++++++++++++++
> > 1 file changed, 50 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/sm6115.dtsi b/arch/arm64/boot/dts/qcom/sm6115.dtsi
> > index 839c603512403..db45337c1082c 100644
> > --- a/arch/arm64/boot/dts/qcom/sm6115.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/sm6115.dtsi
> > [...]
> > @@ -789,6 +801,37 @@ gcc: clock-controller@1400000 {
> > #power-domain-cells = <1>;
> > };
> >
> > + eud: eud@1610000 {
> > + compatible = "qcom,sm6115-eud", "qcom,eud";
> > + reg = <0x0 0x01610000 0x0 0x2000>,
> > + <0x0 0x01612000 0x0 0x1000>,
> > + <0x0 0x003c0000 0x0 0x40000>;
> > + reg-names = "eud-base", "eud-mode-mgr", "tcsr-base";
>
> TCSR is a separate hardware block unrelated to the EUD. IMHO it
> shouldn't be listed as "reg" here.
>
> Typically we describe it as syscon and then reference it from other
> nodes. See e.g. sm8450.dtsi "tcsr: syscon@1fc0000" referenced in &scm
> "qcom,dload-mode = <&tcsr 0x13000>". This is pretty much exactly the
> same use case as you have. It also uses this to write something with
> qcom_scm_io_writel() at the end.
That was discussed a bit during v1 patchset review. Basically, if we
use a tcsr syscon approach here, we will need to define a 'qcom,xx'
vendor specific dt-property and use something like this in the eud
node:
qcom,eud-sec-reg = <&tcsr_reg yyyy>
which would be then used by the eud driver (via
syscon_regmap_lookup_by_phandle()).
But for sm6115 / qcm2290 this would be an over complicated solution as
normally the eud driver (say sc7280) doesn't need tcsr based secure
mode manager access. So defining a new soc / vendor specific
dt-property might be an overkill.
Thanks,
Bhupesh
