[PATCH v12 14/14] arm64: dts: rockchip: enable the NPU on rk3576-rock-4d

[Jiaxing Hu <gahing@gahingwoo.com>]

Enable both RKNN cores and their IOMMUs on the Radxa ROCK 4D, and hand
vdd_npu_s0 to the NPU power domain as its domain-supply, so the rail is
switched by the domain that gates the block.

Measured on a ROCK 4D with this in place. The rail's regulator debugfs
reports open_count 1, so the domain is the consumer that took it. A sampler
running beside an inference caught use_count at 1, and three reads at rest
report use_count 0 with the rail disabled, so it follows the domain rather
than staying on. Over the same run the genpd active_time of all four NPU
domains rises by roughly 60ms per inference, and the inferences either side
of that are 128 of 128 channels against the CPU reference.

Both cores keep npu-supply on the same rail, which the binding requires.
v11 enabled rknn_core_0 alone and left the second to whoever could test it;
it has been tested since. Both cores probe, each with its IOMMU, and a
runtime that deals its submits across the two returns text identical to the
one-core run over nine language models.

Signed-off-by: Jiaxing Hu <gahing@gahingwoo.com>
---
 .../boot/dts/rockchip/rk3576-rock-4d.dts      | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts b/arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts
index 272af1012..93d59c0a9 100644
--- a/arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3576-rock-4d.dts
@@ -722,6 +722,10 @@ &pcie0 {
 	status = "okay";
 };
 
+&pd_npu {
+	domain-supply = <&vdd_npu_s0>;
+};
+
 &pinctrl {
 	hdmi {
 		hdmi_tx_on_h: hdmi-tx-on-h {
@@ -779,6 +783,24 @@ wifi_en_h: wifi-en-h {
 	};
 };
 
+&rknn_core_0 {
+	npu-supply = <&vdd_npu_s0>;
+	status = "okay";
+};
+
+&rknn_mmu_0 {
+	status = "okay";
+};
+
+&rknn_core_1 {
+	npu-supply = <&vdd_npu_s0>;
+	status = "okay";
+};
+
+&rknn_mmu_1 {
+	status = "okay";
+};
+
 &sai6 {
 	status = "okay";
 };
-- 
2.43.0