Re: [PATCH] arm64: dts: ti: k3-j721e-beagleboneai64: Enable ACSPCIE output for PCIe1

[Krzysztof Kozlowski <krzk@kernel.org>]

On 26/11/2024 18:33, Romain Naour wrote:
> From: Romain Naour <romain.naour@skf.com>
> 
> Unlike the SK-TDA4VM (k3-j721e-sk) board, there is no clock generator
> (CDCI6214RGET) on the BeagleBone AI-64 (k3-j721e-beagleboneai64) to
> provide PCIe refclk signal to PCIe Endponts. So the ACSPCIE module must
> provide refclk through PCIe_REFCLK pins.
> 
> Use the new "ti,syscon-acspcie-proxy-ctrl" property to enable ACSPCIE
> module's PAD IO Buffers.
> 
> Signed-off-by: Romain Naour <romain.naour@skf.com>
> ---
> With this patch, we can remove "HACK: Sierra: Drive clock out" patch
> applied on vendor kernel for BeagleBone AI-64:
> https://openbeagle.org/beagleboard/linux/-/commit/ad65d7ef675966cdbc5d75f2bd545fad1914ba9b
> ---
>  arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts |  4 ++++
>  arch/arm64/boot/dts/ti/k3-j721e-main.dtsi          | 10 ++++++++--
>  2 files changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts b/arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts
> index fb899c99753e..681e3af7ce6e 100644
> --- a/arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts
> +++ b/arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts
> @@ -859,6 +859,10 @@ &pcie1_rc {
>  	num-lanes = <2>;
>  	max-link-speed = <3>;
>  	reset-gpios = <&main_gpio0 22 GPIO_ACTIVE_HIGH>;
> +	/* There is no on-board or external reference clock generators,

Please use generic style comments, not netdev.

> +	 * use refclk from the ACSPCIE module's PAD IO Buffers.
> +	 */
> +	ti,syscon-acspcie-proxy-ctrl = <&acspcie0_proxy_ctrl 0x3>;
>  };
>  
>  &ufs_wrapper {
> diff --git a/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi b/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi
> index 0da785be80ff..9f47e7672922 100644
> --- a/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi
> @@ -5,6 +5,7 @@
>   * Copyright (C) 2016-2024 Texas Instruments Incorporated - https://www.ti.com/
>   */
>  #include <dt-bindings/phy/phy.h>
> +#include <dt-bindings/phy/phy-cadence.h>
>  #include <dt-bindings/phy/phy-ti.h>
>  #include <dt-bindings/mux/mux.h>
>  
> @@ -82,6 +83,11 @@ ehrpwm_tbclk: clock-controller@4140 {
>  			reg = <0x4140 0x18>;
>  			#clock-cells = <1>;
>  		};
> +
> +		acspcie0_proxy_ctrl: acspcie0-ctrl@18090 {

Node names should be generic. See also an explanation and list of
examples (not exhaustive) in DT specification:
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation


> +			compatible = "ti,j784s4-acspcie-proxy-ctrl", "syscon";

I am not familiar with naming, so is this j784s4 or j721e or K3 SoC?
Compatible should be SoC specific.

Best regards,
Krzysztof