[PATCH 3/3] ARM: dts: at91: sam9x60: Add spi0 node (flexcom 0)

[Alexander Dahl]

Hello Eugen,

Am Tue, Nov 11, 2025 at 02:33:31PM +0200 schrieb Eugen Hristev:
> 
> 
> On 11/11/25 14:15, Alexander Dahl wrote:
> > Hello Eugen,
> > 
> > Am Tue, Nov 11, 2025 at 01:34:35PM +0200 schrieb Eugen Hristev:
> >>
> >>
> >> On 11/11/25 13:26, Alexander Dahl wrote:
> >>> Copied from linux kernel v6.18-rc4.  Stripped attributes not supported
> >>> by U-Boot drivers (dma, interrupt, fifo-size).
> >>
> >> Hello Alexander,
> >>
> >> Have you tried to configure the build to use upstream DTS ? this should
> >> be available in the U-boot dir. CONFIG_OF_UPSTREAM I believe.
> > 
> > Quick try with _just_ enabling CONFIG_OF_UPSTREAM and adding the
> > obligatory folder to CONFIG_DEFAULT_DEVICE_TREE leads to the expected
> > build errors:
> > 
> >   DTC     dts/upstream/src/arm/microchip/at91-sam9x60_curiosity.dtb
> > Error: …/u-boot/arch/arm/dts/at91-sam9x60_curiosity-u-boot.dtsi:43.1-7 Label or path clk32 not found
> > Error: …/u-boot/arch/arm/dts/at91-sam9x60_curiosity-u-boot.dtsi:51.1-9 Label or path main_rc not found
> > Error: …/u-boot/arch/arm/dts/at91-sam9x60_curiosity-u-boot.dtsi:67.1-16 Label or path pinctrl_sdhci0 not found
> > Error: …/u-boot/arch/arm/dts/at91-sam9x60_curiosity-u-boot.dtsi:79.1-9 Label or path pit64b0 not found
> > Error: …/u-boot/arch/arm/dts/at91-sam9x60_curiosity-u-boot.dtsi:87.1-8 Label or path sdhci0 not found
> > Error: …/u-boot/arch/arm/dts/at91-sam9x60_curiosity-u-boot.dtsi:91.1-13 Label or path slow_rc_osc not found
> > FATAL ERROR: Syntax error parsing input tree
> > 
> > Not bad for the first shot, but I guess at least the clock related
> > issues might get challenging.  However I need to put this aside for later.
> > 
> > One question though, while we are at it:  Would it be possible to
> > define a custom dts in U-Boot and include an upstream .dtsi?
> 
> There is a custom dts in U-boot, in your case sam9x60-u-boot.dtsi, and
> this should be automatically included by the build tool.
> This applies on top of the upstream dts if you select it, or, the
> in-tree DTS.
> You want to do some combo of both or something ? I didn't fully
> understand it.

Sorry, was not clear enough.  For the sam9x60_curiosity case of course
at91-sam9x60_curiosity.dts _and_ sam9x60.dtsi should come from
UPSTREAM, with u-boot specific quirks coming from in-tree
…-u-boot.dtsi files as usual, for both parts.

A custom board dts missing in upstream, would be added to (downstream)
U-Boot in-tree, but it should pick up upstream sam9x60.dtsi,
especially if U-Boot in-tree dtsi gets removed eventually.  Wonder if
that's possible?  Alas, one could simply try, later. ;-)

> In the case of the above errors, it appears the *-u-boot.dtsi  is at
> fault for referencing non-upstream nodes

Probably.

Greets
Alex


> 
> > 
> > Greets
> > Alex
> > 
> >>
> >> Also, if you really want to update this u-boot DT, you would have to
> >> copy it as-is, no stripping. Even if the props are unused. The only real
> >> issue would be if Uboot stops working or gets confused by these extra props
> >>
> >> Eugen>
> >>> Signed-off-by: Alexander Dahl <ada at thorsis.com>
> >>> ---
> >>>  arch/arm/dts/sam9x60.dtsi | 10 ++++++++++
> >>>  1 file changed, 10 insertions(+)
> >>>
> >>> diff --git a/arch/arm/dts/sam9x60.dtsi b/arch/arm/dts/sam9x60.dtsi
> >>> index a33c0d57398..1ee30422518 100644
> >>> --- a/arch/arm/dts/sam9x60.dtsi
> >>> +++ b/arch/arm/dts/sam9x60.dtsi
> >>> @@ -182,6 +182,16 @@
> >>>  				ranges = <0x0 0xf801c000 0x800>;
> >>>  				status = "disabled";
> >>>  
> >>> +				spi0: spi at 400 {
> >>> +					compatible = "microchip,sam9x60-spi", "atmel,at91rm9200-spi";
> >>> +					reg = <0x400 0x200>;
> >>> +					#address-cells = <1>;
> >>> +					#size-cells = <0>;
> >>> +					clocks = <&pmc PMC_TYPE_PERIPHERAL 5>;
> >>> +					clock-names = "spi_clk";
> >>> +					status = "disabled";
> >>> +				};
> >>> +
> >>>  				i2c0: i2c at 600 {
> >>>  					compatible = "microchip,sam9x60-i2c";
> >>>  					reg = <0x600 0x200>;
> >>
> > 
>