On Wed, Nov 21, 2018 at 08:08:08AM -0800, Simon Horman wrote:
> From: Takeshi Kihara <takeshi.kihara.df@xxxxxxxxxxx>
>
> It is incorrect to specify the no-ether-link property for the AVB device on
> the Ebisu board. This is because the property should only be used when a
> board does not provide a proper AVB_LINK signal. However, the Ebisu board
> does provide this signal.
>
> As per 87c059e9c39d ("arm64: dts: renesas: salvator-x: Remove renesas,
> no-ether-link property") this fixes a bug:
>
> Steps to reproduce:
> - start AVB TX stream (Using aplay via MSE),
> - disconnect+reconnect the eth cable,
> - after a reconnection the eth connection goes iteratively up/down
> without user interaction,
> - this may heal after some seconds or even stay for minutes.
>
> As the documentation specifies, the "renesas,no-ether-link" option
> should be used when a board does not provide a proper AVB_LINK signal.
> There is no need for this option enabled on RCAR H3/M3 Salvator-X/XS
> and ULCB starter kits since the AVB_LINK is correctly handled by HW.
>
> Choosing to keep or remove the "renesas,no-ether-link" option will have
> impact on the code flow in the following ways:
> - keeping this option enabled may lead to unexpected behavior since the
> RX & TX are enabled/disabled directly from adjust_link function
> without any HW interrogation,
> - removing this option, the RX & TX will only be enabled/disabled after
> HW interrogation. The HW check is made through the LMON pin in PSR
> register which specifies AVB_LINK signal value (0 - at low level;
> 1 - at high level).
>
> In conclusion, the present change is also a safety improvement because
> it removes the "renesas,no-ether-link" option leading to a proper way
> of detecting the link state based on HW interrogation and not on
> software heuristic.
>
> Fixes: 8441ef643d7d ("arm64: dts: renesas: r8a77990: ebisu: Enable EthernetAVB")
> Signed-off-by: Takeshi Kihara <takeshi.kihara.df@xxxxxxxxxxx>
> [simon: updated changelog]
> Signed-off-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
This seems to have fallen through the cracks.
I have applied it for inclusion in v5.3.
