Re: [PATCH 4/5] arm64: dts: rockchip: Enable all 3 USBs on Turing RK1

From: Jonas Karlman
Date: Thu Sep 12 2024 - 15:53:51 EST


Hi Sam,

On 2024-09-12 04:50, Sam Edwards wrote:
> The Turing RK1 contains 3 different USBs:
> - USB0: USB 2.0, OTG
> - USB1: USB 3.0, host
> - USB2: USB 2.0, host
>
> This patch activates the necessary DT nodes to enable all 3 buses.
>
> Future work will be needed on USB0: it is not USB 3.0, but Linux creates
> an unused USB 3.0 root hub and the controller also requires that USBDP0
> be powered up. However, it is possible to remove this dependency. By
> either patching the xHCI driver to ignore the enumerated USB 3.0 port or
> setting usb3otg0_host_num_u3_port=0 in the GRF to stop the controller
> from enumerating a USB 3.0 port in the first place, neither Linux nor
> the controller will expect USB 3.0 capability, and USBDP0 can then
> safely be removed from the `phys` property.
>
> Signed-off-by: Sam Edwards <CFSworks@xxxxxxxxx>
> ---
> .../boot/dts/rockchip/rk3588-turing-rk1.dtsi | 64 +++++++++++++++++++
> 1 file changed, 64 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/rockchip/rk3588-turing-rk1.dtsi b/arch/arm64/boot/dts/rockchip/rk3588-turing-rk1.dtsi
> index f6a12fe12d45..6036c4fe6727 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3588-turing-rk1.dtsi
> +++ b/arch/arm64/boot/dts/rockchip/rk3588-turing-rk1.dtsi
> @@ -666,3 +666,67 @@ &uart9 {
> pinctrl-0 = <&uart9m0_xfer>;
> status = "okay";
> };
> +
> +/* USB 0: USB 2.0 only, OTG-capable */
> +&u2phy0 {
> + status = "okay";
> +};
> +
> +&u2phy0_otg {
> + status = "okay";
> +};
> +
> +&usbdp_phy0 {
> + /*
> + * TODO: On the RK1, USBDP0 drives the DisplayPort pins, and is not
> + * involved in this USB2-only bus. However, if the USB3 port is
> + * enabled in the xHCI below, the controller will expect this PHY to be
> + * powered up and holding RX_STATUS idle, or else it will generate an
> + * endless stream of CSC events whenever a device is plugged in. Until
> + * there is a way to communicate to usb_host0_xhci that it doesn't have
> + * a USB3 port, we have no choice but to power up USBDP0.
> + */

Sounds like this may be missing

rockchip,dp-lane-mux = <0 1 2 3>;

or

rockchip,dp-lane-mux = <3 2 1 0>;

if all lanes are used for DP and none are used for USB.

It should help describe the hw and also help the driver set mode to
UDPHY_MODE_DP and that should disable the u3 port, or there may be an
issue to fix in the phy driver.

> + status = "okay";
> +};
> +
> +&usb_host0_xhci {
> + extcon = <&u2phy0>;
> + maximum-speed = "high-speed";

If this only use the USB2 phy, this should probably also override the
default phys and phy-names props with:

phys = <&u2phy0_otg>;
phy-names = "usb2-phy";

Regards,
Jonas

> + status = "okay";
> +};
> +
> +/* USB 1: USB 3.0, host only */
> +&u2phy1 {
> + status = "okay";
> +};
> +
> +&u2phy1_otg {
> + status = "okay";
> +};
> +
> +&usbdp_phy1 {
> + status = "okay";
> +};
> +
> +&usb_host1_xhci {
> + extcon = <&u2phy1>;
> + dr_mode = "host";
> + status = "okay";
> +};
> +
> +/* USB 2: USB 2.0, host only */
> +&u2phy2 {
> + status = "okay";
> +};
> +
> +&u2phy2_host {
> + status = "okay";
> +};
> +
> +&usb_host0_ehci {
> + status = "okay";
> +};
> +
> +&usb_host0_ohci {
> + status = "okay";
> +};