[PATCH 0/5] riscv: dts: spacemit: serial/i2c/ethernet improvements for the K3 Pico-ITX board

[PATCH 0/5] riscv: dts: spacemit: serial/i2c/ethernet improvements for the K3 Pico-ITX board

[Aurelien Jarno]

This patch series tries to improve the K3 Pico-ITX board DTS by configuring the
default baud rate for the serial port, enabling the 24c02 eeprom on i2c2,
adding aliases for i2c2 and i2c8 ports, and enabling power saving features on
the RTL8211F PHY.

Aurelien Jarno (5):
  riscv: dts: spacemit: set console baud rate on K3 Pico-ITX board
  riscv: dts: spacemit: enable the i2c2 adapter on K3 Pico-ITX board
  riscv: dts: spacemit: add 24c02 eeprom on K3 Pico-ITX board
  riscv: dts: spacemit: add i2c aliases on K3 Pico-ITX board
  riscv: dts: spacemit: improve RTL8211F PHY configuration on K3
    Pico-ITX board

 arch/riscv/boot/dts/spacemit/k3-pico-itx.dts | 42 +++++++++++++++++++-
 arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi | 11 +++++
 2 files changed, 52 insertions(+), 1 deletion(-)

-- 
2.53.0

[PATCH 1/5] riscv: dts: spacemit: set console baud rate on K3 Pico-ITX board

[Aurelien Jarno]

Because the default console's baud rate is not set, defconfig kernels do
not have any serial output on this platform. Set the baud rate to
115200, matching what is used by U-Boot etc on this platform.

Fixes: 7a6131804986 ("riscv: dts: spacemit: add K3 Pico-ITX board support")
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
 arch/riscv/boot/dts/spacemit/k3-pico-itx.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
index b89c1521e6649..509cebc0c9568 100644
--- a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
+++ b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
@@ -18,7 +18,7 @@ aliases {
 	};
 
 	chosen {
-		stdout-path = "serial0";
+		stdout-path = "serial0:115200n8";
 	};
 
 	memory@100000000 {
-- 
2.53.0

Re: [PATCH 1/5] riscv: dts: spacemit: set console baud rate on K3 Pico-ITX board

[Guodong Xu]

Hi Aurelien,

On 2026-06-20 08:22, Aurelien Jarno wrote:
>Because the default console's baud rate is not set, defconfig kernels do
>not have any serial output on this platform. Set the baud rate to
>115200, matching what is used by U-Boot etc on this platform.
>
>Fixes: 7a6131804986 ("riscv: dts: spacemit: add K3 Pico-ITX board support")
>Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

Thanks for the patch.

Reviewed-by: Guodong Xu <docular.xu@gmail.com>

>---
> arch/riscv/boot/dts/spacemit/k3-pico-itx.dts | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
>index b89c1521e6649..509cebc0c9568 100644
>--- a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
>+++ b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
>@@ -18,7 +18,7 @@ aliases {
> 	};
>
> 	chosen {
>-		stdout-path = "serial0";
>+		stdout-path = "serial0:115200n8";
> 	};
>
> 	memory@100000000 {
>-- 
>2.53.0
>
>
>_______________________________________________
>linux-riscv mailing list
>linux-riscv@lists.infradead.org
>http://lists.infradead.org/mailman/listinfo/linux-riscv

[PATCH 2/5] riscv: dts: spacemit: enable the i2c2 adapter on K3 Pico-ITX board

[Aurelien Jarno]

Define I2C2 pinctrl properties, and enable it on the K3 Pico-ITX board.
It will be used by the 24c02 eeprom.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
 arch/riscv/boot/dts/spacemit/k3-pico-itx.dts |  6 ++++++
 arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi | 11 +++++++++++
 2 files changed, 17 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
index 509cebc0c9568..5fe9041ec5702 100644
--- a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
+++ b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
@@ -43,6 +43,12 @@ reg_aux_vcc5v: regulator-aux-vcc5v {
 	};
 };
 
+&i2c2 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&i2c2_1_cfg>;
+	status = "okay";
+};
+
 &i2c8 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c8_cfg>;
diff --git a/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi b/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
index 3ee1471f37985..2017aa14fb424 100644
--- a/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
@@ -78,6 +78,17 @@ gmac1-phy-0-pins {
 		};
 	};
 
+	/omit-if-no-ref/
+	i2c2_1_cfg: i2c2-1-cfg {
+		i2c2-0-pins {
+			pinmux = <K3_PADCONF(46, 5)>,	/* i2c2 scl */
+				 <K3_PADCONF(47, 5)>;	/* i2c2 sda */
+
+			bias-pull-up= <0>;
+			drive-strength = <25>;
+		};
+	};
+
 	/omit-if-no-ref/
 	i2c8_cfg: i2c8-cfg {
 		i2c8-pins {
-- 
2.53.0

Re: [PATCH 2/5] riscv: dts: spacemit: enable the i2c2 adapter on K3 Pico-ITX board

[Aurelien Jarno]

Both issues reported by Sashiko AI (see below) are valid, I'll submit a 
v2 fixing them, but I'll first leave a few more days for humans to also 
have a look at the patches.

Regards
Aurelien

On 2026-06-20 06:29, sashiko-bot@kernel.org wrote:
> Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
> - [Low] The pinctrl subnode is named `i2c2-0-pins` but belongs to the `i2c2-1-cfg` parent node.
> - [Low] Missing space before the assignment operator in `bias-pull-up= <0>;`.
> --
> 
> commit 4dc6c92d42831e85b38f3350c15707d0e2b3af18
> Author: Aurelien Jarno <aurelien@aurel32.net>
> 
> riscv: dts: spacemit: enable the i2c2 adapter on K3 Pico-ITX board
> 
> This commit defines the I2C2 pinctrl properties and enables the adapter
> on the K3 Pico-ITX board. It will be used by the 24c02 eeprom.
> 
> > diff --git a/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi b/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
> > index 23899d3f308a0..c9fe9c2e5aeee 100644
> > --- a/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
> > +++ b/arch/riscv/boot/dts/spacemit/k3-pinctrl.dtsi
> 
> [ ... ]
> 
> > @@ -45,6 +45,17 @@ gmac0-phy-0-pins {
> >  		};
> >  	};
> >  
> > +	/omit-if-no-ref/
> > +	i2c2_1_cfg: i2c2-1-cfg {
> > +		i2c2-0-pins {
> 
> [Severity: Low]
> This isn't a bug, but should this subnode be named i2c2-1-pins to match
> the i2c2-1-cfg parent node? It seems to diverge from the standard naming
> pattern where the suffix of the parent and child matches.
> 
> > +			pinmux = <K3_PADCONF(46, 5)>,	/* i2c2 scl */
> > +				 <K3_PADCONF(47, 5)>;	/* i2c2 sda */
> > +
> > +			bias-pull-up= <0>;
> 
> [Severity: Low]
> This isn't a bug, but there is a missing space before the equals sign
> here, which diverges from the spacing used in the surrounding code.
> 
> > +			drive-strength = <25>;
> > +		};
> > +	};
> 
> -- 
> Sashiko AI review · https://sashiko.dev/#/patchset/20260620062238.3199108-1-aurelien@aurel32.net?part=2
> 

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
aurelien@aurel32.net                     http://aurel32.net

[PATCH 3/5] riscv: dts: spacemit: add 24c02 eeprom on K3 Pico-ITX board

[Aurelien Jarno]

The K3 Pico-ITX board includes a 24c02 eeprom, that stores the product
name, the part name, the MAC address of the network interfaces and the
board's serial number. These values are also exposed via an
onie,tlv-layout nvmem layout.

The eeprom is marked as read-only since its contents are not supposed to
be modified.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
 arch/riscv/boot/dts/spacemit/k3-pico-itx.dts | 30 ++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
index 5fe9041ec5702..0a0c221c99e74 100644
--- a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
+++ b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
@@ -47,6 +47,36 @@ &i2c2 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&i2c2_1_cfg>;
 	status = "okay";
+
+	eeprom@50 {
+		compatible = "atmel,24c02";
+		reg = <0x50>;
+		pagesize = <8>;
+		read-only;
+		size = <256>;
+		status = "okay";
+
+		nvmem-layout {
+			compatible = "onie,tlv-layout";
+
+			mac-address {
+				#nvmem-cell-cells = <1>;
+			};
+
+			num-macs {
+			};
+
+			part-number {
+			};
+
+			product-name {
+			};
+
+			serial-number {
+			};
+
+		};
+	};
 };
 
 &i2c8 {
-- 
2.53.0

[PATCH 4/5] riscv: dts: spacemit: add i2c aliases on K3 Pico-ITX board

[Aurelien Jarno]

Add i2c aliases for i2c2 and i2c8 on K3 Pico-ITX board. This is useful
to keep a stable number for the /dev entries after loading the i2c-dev
module.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
 arch/riscv/boot/dts/spacemit/k3-pico-itx.dts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
index 0a0c221c99e74..bf64b6c6f867f 100644
--- a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
+++ b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
@@ -14,6 +14,8 @@ / {
 
 	aliases {
 		ethernet0 = &eth0;
+		i2c2 = &i2c2;
+		i2c8 = &i2c8;
 		serial0 = &uart0;
 	};
 
-- 
2.53.0

[PATCH 5/5] riscv: dts: spacemit: improve RTL8211F PHY configuration on K3 Pico-ITX board

[Aurelien Jarno]

Vendor kernel enabled ALDPS (Advanced Link Down Power Saving) on the
RTL8211F PHY to save power when link down.

Vendor kernel also disabled the 125MHz clkout clock signal, and indeed
the schematics confirms that it only goes to a test point (TP14), so
let's do the same.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
 arch/riscv/boot/dts/spacemit/k3-pico-itx.dts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
index bf64b6c6f867f..e12d798b48a49 100644
--- a/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
+++ b/arch/riscv/boot/dts/spacemit/k3-pico-itx.dts
@@ -234,6 +234,8 @@ phy0: phy@1 {
 			reset-gpios = <&gpio 0 15 GPIO_ACTIVE_LOW>;
 			reset-assert-us = <10000>;
 			reset-deassert-us = <10000>;
+			realtek,aldps-enable;
+			realtek,clkout-disable;
 		};
 	};
 };
-- 
2.53.0