arm64: dts: imx95-19x19-evk: Add supports-clkreq property to PCIe M.2 port

According to PCIe r6.1, sec 5.5.1.

The following rules define how the L1.1 and L1.2 substates are entered:
Both the Upstream and Downstream Ports must monitor the logical state of
the CLKREQ# signal.

Typical implement is using open drain, which connect RC's clkreq# to
EP's clkreq# together and pull up clkreq#.

imx95-19x19-evk matches this requirement, so add supports-clkreq to
allow PCIe device enter ASPM L1 Sub-State.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

diff --git a/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts b/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
index 9f968feccef67c1963cf5518b1c7176508566a60..0f470d3eb9af48c4118d120ecfc25b839aa387b1 100644 (file)
--- a/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
+++ b/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
@@ -542,6 +542,7 @@
        pinctrl-names = "default";
        reset-gpio = <&i2c7_pcal6524 5 GPIO_ACTIVE_LOW>;
        vpcie-supply = <&reg_pcie0>;
+       supports-clkreq;
        status = "okay";
 };