Re: [PATCH v5 2/4] dts: zynqmp: add properties for TCM in remoteproc

[Mathieu Poirier <mathieu.poirier@linaro.org>]

On Mon, Oct 02, 2023 at 03:54:30PM -0500, Tanmay Shah wrote:
> 
> On 10/2/23 3:17 PM, Mathieu Poirier wrote:
> > On Mon, 2 Oct 2023 at 11:12, Tanmay Shah <tanmay.shah@amd.com> wrote:
> > >
> > >
> > > On 10/2/23 11:25 AM, Tanmay Shah wrote:
> > > > Hi Mathieu,
> > > >
> > > > Thanks for the reviews. Please find my comments below.
> > > >
> > > > On 10/2/23 10:55 AM, Mathieu Poirier wrote:
> > > > > On Thu, Sep 28, 2023 at 08:58:58AM -0700, Tanmay Shah wrote:
> > > > > > Add properties as per new bindings in zynqmp remoteproc node
> > > > > > to represent TCM address and size. This patch configures
> > > > > > RPU in split mode and adds TCM information accordingly.
> > > > > >
> > > > >
> > > > > Why is this changed from lockstep to split mode?  What about all the people out
> > > > > there that are expecting a lockstep mode?
> > > >
> > > > I agree, this should have been in split mode in the first place as we would like to demonstrate use of both
> > > >
> > > > RPUs with two separate demo firmwares which is the best use of the
> > > >
> > > > hardware and the most preferred use of zynqmp platform by people. That motivates to change
> > > >
> > > > this to split mode.
> > > >
> > > >
> > > > Now changing this may not be problem for lot of people with following reasons.
> > > >
> > > > The firmwares that are only using first 64KB of TCM memory, they can easily run in split mode as well.
> > > >
> > > > Also rpmsg vring information isn't available in device-tree yet, so I am hoping that firmware that
> > > >
> > > > are using upstream device-tree are not that big yet.
> > > >
> > > > If we change this to split mode before introducing rpmsg related nodes, I bet it will affect very less number of people.
> > > >
> > > >
> > > > For lockstep mode the example is available in dt-bindings document.
> > > >
> >
> > I could use the same argument for the split mode, i.e default is
> > lockstep and there is an example in the dt-bindings document for split
> > mode.
> >
> > > > So, if people need lockstep mode for any reason, all they need to change is xlnx,cluster-mode property from 0 to 1 and TCM nodes
> > > >
> > > > from bindings document.
> > > >
> > > >
> > > > If you think it's crucial to mention all above, I can send new patch with all above info in commit message.
> > >
> > > Something to add to this. So, let's say if we don't change it now, what would be good time to change it?
> > >
> >
> > The best way to go about this is to introduce another DT that is
> > tailored for split mode.  That way people can choose to boot their
> > device in a specific mode using the DT.  If you decide to go this way,
> > look at how ST has split their DT for different boards - search for
> > "m4_rproc" under " arch/arm/boot/dts/st".
> 
> Thanks for the suggestion. I looked at the example and I think it will work.
> 
> I have following idea.
> 
> So, if I understand this correctly, we introduce two separate nodes in device-tree.
> 
> SOC dtsi file: zynqmp.dtsi
> 
> remoteproc_lockstep: remoteproc@... {
> 
> . . .
> 
> status = "disabled";

I don't think you need the "status"

> 
> };
> 
> 
> remoteproc_split: remoteproc@... {
> 
>  . . .
> 
> status = "disabled";
> 
> };
> 
> 
> And then in board dts enable whatever mode is needed for that board:
> 
> *zcu102*.dts
> 
> &remoteproc_split {
> 
> status = "okay";
> 
> };

Exactly.  Again, I don't think the "status" is needed.

> 
> This sounds like good idea, I hope this is what you mean.
> 
> Please let me know if I am missing something.
> 
> 
> >
> > > As I am hopping to use RPU1 as well with upstream device-tree. Please let me know some suggestion to work this.
> > >
> > > Thanks and again as always appreciate complete reviews,
> > >
> > > Tanmay
> > >
> > >
> > > >
> > > >
> > > > >
> > > > > > Signed-off-by: Tanmay Shah <tanmay.shah@amd.com>
> > > > > > ---
> > > > > >  arch/arm64/boot/dts/xilinx/zynqmp.dtsi | 28 ++++++++++++++++++++------
> > > > > >  1 file changed, 22 insertions(+), 6 deletions(-)
> > > > > >
> > > > > > diff --git a/arch/arm64/boot/dts/xilinx/zynqmp.dtsi b/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> > > > > > index b61fc99cd911..01e12894c88e 100644
> > > > > > --- a/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> > > > > > +++ b/arch/arm64/boot/dts/xilinx/zynqmp.dtsi
> > > > > > @@ -247,19 +247,35 @@ fpga_full: fpga-full {
> > > > > >           ranges;
> > > > > >   };
> > > > > >
> > > > > > - remoteproc {
> > > > > > + remoteproc@ffe00000 {
> > > > > >           compatible = "xlnx,zynqmp-r5fss";
> > > > > > -         xlnx,cluster-mode = <1>;
> > > > > > +         xlnx,cluster-mode = <0>;
> > > > > >
> > > > > > -         r5f-0 {
> > > > > > +         #address-cells = <2>;
> > > > > > +         #size-cells = <2>;
> > > > > > +
> > > > > > +         ranges = <0x0 0x0 0x0 0xffe00000 0x0 0x10000>,
> > > > > > +                  <0x0 0x20000 0x0 0xffe20000 0x0 0x10000>,
> > > > > > +                  <0x1 0x0 0x0 0xffe90000 0x0 0x10000>,
> > > > > > +                  <0x1 0x20000 0x0 0xffeb0000 0x0 0x10000>;
> > > > > > +
> > > > > > +         r5f@0 {
> > > > > >                   compatible = "xlnx,zynqmp-r5f";
> > > > > > -                 power-domains = <&zynqmp_firmware PD_RPU_0>;
> > > > > > +                 reg = <0x0 0x0 0x0 0x10000>, <0x0 0x20000 0x0 0x10000>;
> > > > > > +                 reg-names = "atcm", "btcm";
> > > > > > +                 power-domains = <&zynqmp_firmware PD_RPU_0>,
> > > > > > +                                 <&zynqmp_firmware PD_R5_0_ATCM>,
> > > > > > +                                 <&zynqmp_firmware PD_R5_0_BTCM>;
> > > > > >                   memory-region = <&rproc_0_fw_image>;
> > > > > >           };
> > > > > >
> > > > > > -         r5f-1 {
> > > > > > +         r5f@1 {
> > > > > >                   compatible = "xlnx,zynqmp-r5f";
> > > > > > -                 power-domains = <&zynqmp_firmware PD_RPU_1>;
> > > > > > +                 reg = <0x1 0x0 0x0 0x10000>, <0x1 0x20000 0x0 0x10000>;
> > > > > > +                 reg-names = "atcm", "btcm";
> > > > > > +                 power-domains = <&zynqmp_firmware PD_RPU_1>,
> > > > > > +                                 <&zynqmp_firmware PD_R5_1_ATCM>,
> > > > > > +                                 <&zynqmp_firmware PD_R5_1_BTCM>;
> > > > > >                   memory-region = <&rproc_1_fw_image>;
> > > > > >           };
> > > > > >   };
> > > > > > --
> > > > > > 2.25.1
> > > > > >