[PATCH v6 03/11] arm64: dts: imx8mm-evk: Add supports-clkreq property to PCIe M.2 port

[Richard Zhu]

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#.

imx8mm-evk matches this requirement, so add supports-clkreq to allow
PCIe device enter ASPM L1 Sub-State.

Signed-off-by: Richard Zhu <hongxing.zhu at nxp.com>
---
 arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
index ff7ca20752309..6eab8a6001dbf 100644
--- a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
@@ -542,6 +542,7 @@ &pcie0 {
 	assigned-clock-parents = <&clk IMX8MM_SYS_PLL2_50M>,
 				 <&clk IMX8MM_SYS_PLL2_250M>;
 	vpcie-supply = <&reg_pcie0>;
+	supports-clkreq;
 	status = "okay";
 };
 
-- 
2.37.1