Re: [PATCH 2/2] arm: dts: rk356x: rock3a: disable pcie3x2

[Marco Felsch <m.felsch@pengutronix.de>]

Hi Ahmad,

On 26-01-20, Ahmad Fatoum wrote:
> The board hangs occasionally on PCI probe after:
> 
>   phy7: lane number 0, val 1
> 
> On other boots, it continues to:
> 
>   rockchip-dw-pcie 3c0800000.pcie@fe280000.of: Phy link never came up
> 
> In both cases, the hang affects the second PCIe host controller
> to probe and the first probe never hangs:
> 
>   rockchip-dw-pcie 3c0000000.pcie@fe260000.of: Phy link never came up
> 
> This hang happens on the very first read access to the PCI controller
> at register PCIE_ATU_VIEWPORT. Reading Linux code, the first access
> seems to be to PCIE_VERSION_NUMBER (0x8F8), but accessing that in
> barebox equally hangs from time to time.
> 
> My board doesn't have any PCIe devices connected and this hang
> doesn't happen in Linux and doesn't happen on the QNAP
> TS433-eU, which is also RK3568, but actually has PCIe devices, which are
> probed normally.
> 
> Disable the device in barebox, so the board is usable with
> rockchip_v8_defconfig, which enables the PCI driver.
> barebox,status is used, so the Linux device tree is not affected.

The barebox internal device-tree is passed to Linux? Else we just can
make use of the "normal" status field since it would be not propagated
to Linux as well.

Regards,
  Marco

> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  arch/arm/dts/rk3568-rock-3a.dts | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/arch/arm/dts/rk3568-rock-3a.dts b/arch/arm/dts/rk3568-rock-3a.dts
> index bcbfab14a580..b7258d7e61b3 100644
> --- a/arch/arm/dts/rk3568-rock-3a.dts
> +++ b/arch/arm/dts/rk3568-rock-3a.dts
> @@ -55,3 +55,7 @@ environment_sd: partition@408000 {
>  		};
>  	};
>  };
> +
> +&pcie3x2 {
> +	barebox,status = "disabled";
> +};
> -- 
> 2.47.3
> 
> 
> 

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