Add supports-clkreq and the corresponding pinmux configurations for PCIe
ASPM L1 substates on the Rock 5B, 5B+ and 5T.
The supports-clkreq flag informs the PCIe controller that the hardware
routing for the CLKREQ# sideband signal is present. This enables support
for PCIe ASPM (Active State Power Management) L1 substates, allowing for
better power efficiency.

Cc: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Anand Moon <redacted>
---
Rock5b schematics.
[1]  https://dl.radxa.com/rock5/5b+/docs/hw/radxa_rock5bp_v1.2_schematic.pdf
v2: drop the clkreq pinctrl for pcie3x4 as suggeested by Shwan Lin.
[2] https://lore.kernel.org/all/20260311115502.7353-1-linux.amoon@gmail.com/ (local)
---
 arch/arm64/boot/dts/rockchip/rk3588-rock-5b-5bp-5t.dtsi | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3588-rock-5b-5bp-5t.dtsi b/arch/arm64/boot/dts/rockchip/rk3588-rock-5b-5bp-5t.dtsi
index b3e76ad2d8694..bf4a1d2e55ca3 100644
--- a/arch/arm64/boot/dts/rockchip/rk3588-rock-5b-5bp-5t.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3588-rock-5b-5bp-5t.dtsi

@@ -468,7 +468,8 @@ map1 {
 
 &pcie2x1l0 {
 	pinctrl-names = "default";
-	pinctrl-0 = <&pcie2_0_rst>;
+	pinctrl-0 = <&pcie2_0_rst>, <&pcie30x1m1_0_clkreqn>;
+	supports-clkreq;
 	reset-gpios = <&gpio4 RK_PA5 GPIO_ACTIVE_HIGH>;
 	vpcie3v3-supply = <&vcc3v3_pcie2x1l0>;
 	status = "okay";

@@ -476,7 +477,8 @@ &pcie2x1l0 {
 
 &pcie2x1l2 {
 	pinctrl-names = "default";
-	pinctrl-0 = <&pcie2_2_rst>;
+	pinctrl-0 = <&pcie2_2_rst>, <&pcie20x1m0_clkreqn>;
+	supports-clkreq;
 	reset-gpios = <&gpio3 RK_PB0 GPIO_ACTIVE_HIGH>;
 	vpcie3v3-supply = <&vcc3v3_pcie2x1l2>;
 	status = "okay";

base-commit: f338e77383789c0cae23ca3d48adcc5e9e137e3c
-- 
2.50.1