[PATCH v4 2/2] arm64: dts: ti: k3-j721e-beagleboneai64: Enable ACSPCIE output for PCIe1

[Siddharth Vadapalli]

On Thu, Jan 09, 2025 at 11:26:27AM +0100, Romain Naour wrote:

Hello Romain,

> From: Romain Naour <romain.naour at 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.
> 
> Cc: Siddharth Vadapalli <s-vadapalli at ti.com>
> Signed-off-by: Romain Naour <romain.naour at 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

[trimmed]

> diff --git a/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi b/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi
> index af3d730154ac..32a232a90100 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 at 4140 {
>  			reg = <0x4140 0x18>;
>  			#clock-cells = <1>;
>  		};
> +
> +		acspcie0_proxy_ctrl: syscon at 18090 {
> +			compatible = "ti,j721e-acspcie-proxy-ctrl", "syscon";
> +			reg = <0x18090 0x4>;

0x_0011_8090 is probably *not* the "PROXY" register i.e. it could be
locked with the help of "CTRLMMR_LOCK0_KICK0" and "CTRLMMR_LOCK0_KICK1"
registers, in which case the CTRL_MMR region needs to be unlocked to write
to that register. On J784S4, that happens to be true, which is why the
proxy register 0x_0011_a090 was used at [0]. Please test with 0x_0011_a090
which is the "PROXY" register on J721E as well, i.e. it can be written to
unconditionally.

[0]:
https://lore.kernel.org/r/20240930111505.3101047-1-s-vadapalli@ti.com/

[trimmed]

Regards,
Siddharth.