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

[Marco Felsch]

On 26-01-21, 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 at 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 at 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.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>

Reviewed-by: Marco Felsch <m.felsch at pengutronix.de>