Re: [PATCH v2 0/4] Add overlays to disable optional hardware in k3-am6xx-phycore-som boards

[Wadim Egorov]

Add: Daniel Schultz

Am 03.06.24 um 19:41 schrieb Vignesh Raghavendra:
> Hi Nathan,
>
> On 29/05/24 04:21, Nathan Morrisson wrote:
> > Add three overlays to disable the eth phy, rtc, and spi nor. These
> > overlays will be used to disable device tree nodes for components
> > that are optionally not populated.
> >
> > v2:
> >    - Add build time tests in makefile
> >
> > Nathan Morrisson (4):
> >    arm64: dts: ti: k3-am64-phycore-som: Add serial_flash label
>
>
> >    arm64: dts: ti: k3-am6xx-phycore-som: Add overlay to disable eth phy
> >    arm64: dts: ti: k3-am6xx-phycore-som: Add overlay to disable rtc
> >    arm64: dts: ti: k3-am6xx-phycore-som: Add overlay to disabl spi nor
> >
> >   arch/arm64/boot/dts/ti/Makefile               | 17 +++++++++++++++++
> >   .../boot/dts/ti/k3-am64-phycore-som.dtsi      |  2 +-
> >   .../ti/k3-am6xx-phycore-disable-eth-phy.dtso  | 19 +++++++++++++++++++
> >   .../dts/ti/k3-am6xx-phycore-disable-rtc.dtso  | 15 +++++++++++++++
> >   .../ti/k3-am6xx-phycore-disable-spi-nor.dtso  | 15 +++++++++++++++
> >   5 files changed, 67 insertions(+), 1 deletion(-)
>
> >   create mode 100644 arch/arm64/boot/dts/ti/k3-am6xx-phycore-disable-eth-phy.dtso
> >   create mode 100644 arch/arm64/boot/dts/ti/k3-am6xx-phycore-disable-rtc.dtso
> >   create mode 100644 arch/arm64/boot/dts/ti/k3-am6xx-phycore-disable-spi-nor.dtso
>
> I am not sure if this a common practice to have overlays to disable
> missing components (at least I dont see such dtso in kernel). I would
> like to see an what DT maintainers feel as such dtsos can explode in
> numbers.
>
> Is this something that U-Boot can detect and fix up for the Linux DT?
>
> Unpopulated SPI flash and RTC should ideally not be an issue as drivers
> would gracefully fail albeit with some sort of error msg.
> Not so sure about Eth PHYs though.
>
> Also, Are these dtso's mutually exclusive? ie can SoM have SPI flash but
> not RTC, have RTC and SPI Flash but no ETH PHY?