[PATCH 0/4] Use just one DTS file for all Espressobin variants

[Pali Rohár]

On Wednesday 02 December 2020 09:09:15 Stefan Roese wrote:
> On 02.12.20 01:33, Pali Rohár wrote:
> > On Wednesday 25 November 2020 19:20:06 Pali Rohár wrote:
> > > This patch series change Espressobin code to use in U-Boot just one DTS
> > > file for all Espressobin variants. Therefore DT compatible string
> > > globalscale,espressobin-emmc is not used anymore as it is not needed.
> > > 
> > > It means that setup and compilation of U-Boot for Espressobin is less
> > > complicated and more simple. As there is no need to check for HW details
> > > and just one U-Boot binary would work for all Espressobin variants.
> > > 
> > > First two patches just revert previous eMMC support and next two patches
> > > add support for eMMC in way that just one DTS file is used and fdtfile
> > > env variable is correctly set for any Espressobin variant.
> > > 
> > > We have tested that fdtfile env variable is correctly set on Espressobin
> > > variants with eMMC, without eMMC, with DDR3 RAM and also with DDR4 RAM.
> > > Also that eMMC is working on Espressobin variant with eMMC.
> > 
> > Stefan, could you please review this patch series?
> 
> I like the approach in general to simplify things. One comment though:
> 
> AFAICT, Linux uses multiple dts/dtsi files for espressobin. So your
> approach to move to one single file contradicts the (planned after
> comphy conversion) move to the Linux dts/dtsi files.

After comphy conversion we can use e.g. Linux dtsi file and create one
main U-Boot dts file which would contain all nodes enabled and in U-Boot
code disable nodes which are not present/relevant. This patch series
allows to detect all variants v5, v7, with emmc, without emmc; so we can
reconstruct dts file at U-Boot runtime. In Linux we also simplified dts
files as much as possible, so all options are in common dtsi file and
only variant relevant changes (enable/disable nodes) are in dts files.

> > Andre, are you fine with these changes? I would like to get your
> > acknowledgment or review comment what needs to be changed or improved as
> > this patch series basically rework your code (which is first reverted
> > and them implemented in different way).
> 
> Yes. Andre please also comment on this.
> 
> Thanks,
> Stefan
> 
> > > Pali Rohár (4):
> > >    Revert "arm64: dts: armada-3720-espressobin: split common parts to
> > >      .dtsi"
> > >    Revert "arm64: dts: a3720: add support for espressobin with populated
> > >      emmc"
> > >    arm: mvebu: Espressobin: Add support for emmc into dts file
> > >    arm: mvebu: Espressobin: Detect presence of emmc at runtime
> > > 
> > >   arch/arm/dts/Makefile                         |   1 -
> > >   arch/arm/dts/armada-3720-espressobin-emmc.dts |  44 -----
> > >   arch/arm/dts/armada-3720-espressobin.dts      | 186 +++++++++++++++++-
> > >   arch/arm/dts/armada-3720-espressobin.dtsi     | 167 ----------------
> > >   board/Marvell/mvebu_armada-37xx/board.c       |   6 +-
> > >   doc/README.marvell                            |   7 +-
> > >   6 files changed, 186 insertions(+), 225 deletions(-)
> > >   delete mode 100644 arch/arm/dts/armada-3720-espressobin-emmc.dts
> > >   delete mode 100644 arch/arm/dts/armada-3720-espressobin.dtsi
> > > 
> > > -- 
> > > 2.20.1
> > > 
> 
> 
> Viele Grüße,
> Stefan
> 
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