Re: [PATCH v3 08/10] riscv: dts: renesas: Add minimal DTS for Renesas RZ/Five SMARC EVK

From: Lad, Prabhakar
Date: Thu Sep 15 2022 - 18:52:00 EST


On Thu, Sep 15, 2022 at 11:44 PM <Conor.Dooley@xxxxxxxxxxxxx> wrote:
>
>
>
> On 15/09/2022 23:41, Lad, Prabhakar wrote:
> > Hi Conor,
> >
> > Thank you for the review.
> >
> > On Thu, Sep 15, 2022 at 10:56 PM <Conor.Dooley@xxxxxxxxxxxxx> wrote:
> >>
> >> On 15/09/2022 19:15, Prabhakar wrote:
> >>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> >>>
> >>> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> >>>
> >>> Enable the minimal blocks required for booting the Renesas RZ/Five
> >>> SMARC EVK with initramfs.
> >>>
> >>> Below are the blocks enabled:
> >>> - CPG
> >>> - CPU0
> >>> - DDR (memory regions)
> >>> - PINCTRL
> >>> - PLIC
> >>> - SCIF0
> >>>
> >>> Note we have deleted the nodes from the DT for which support needs to be
> >>> added for RZ/Five SoC and are enabled by RZ/G2UL SMARC EVK SoM/carrier
> >>> board DTS/I.
> >>
> >> idk, I am not sure what to think of this approach.
> >>
> >> What do you mean by "for which support needs to be added"? If the support
> >> does not exist yet, then is surely you can just add the nodes and it will
> >> be fine?
> >>
> > As pointed out previously, I am re-using the below files [1] (SoM) and
> > [2] (Carrier board) as the RZ/Five SMARC EVK is pin compatible. Since
> > [1] and [2] enable almost all the peripherals (status = okay) on the
> > RZ/G2UL SMARC EVK which are supported. For example [1] enables SDHI0/1
> > this high speed block needs DMA and without cache management fixed on
> > Andes core we cannot enable this on RZ/Five SoC so currently a
> > placeholder is added for it in the RZ/FIve SoC DTSI and is deleted in
> > the board DTS file.
> >
> > Below blocks suffer the cache management issue:
> > - DMAC
> > - ETH
> > - SDHI
> > - USB
> >
> > Rest of the blocks will be gradually enabled (as soon as this initial
> > patchset is merged) along with the DT binding doc updates.
> >
> > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/renesas/rzg2ul-smarc-som.dtsi?h=v6.0-rc5
> > [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/renesas/rzg2ul-smarc.dtsi?h=v6.0-rc5
>
>
> Explanations are reasonable, but again - that information is important
> and really needs to be included in the commit message etc.
>
Sure, I will update the commit message while sending the v4.

Cheers,
Prabhakar