4.14-stable review patch. If anyone has any objections, please let me know.
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From: Bogdan Mirea Bogdan-Stefan_Mirea@mentor.com
[ Upstream commit 7d2901f809c110bd9a261e879d59efe62e3bc758 ]
The present change is a bug fix for AVB link iteratively up/down.
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: dc36965a8905 ("arm64: dts: r8a7796: salvator-x: Enable EthernetAVB") Fixes: 6fa501c549aa ("arm64: dts: r8a7795: enable EthernetAVB on Salvator-X") Signed-off-by: Bogdan Mirea Bogdan-Stefan_Mirea@mentor.com Signed-off-by: Vladimir Zapolskiy vladimir_zapolskiy@mentor.com Signed-off-by: Simon Horman horms+renesas@verge.net.au Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/boot/dts/renesas/ulcb.dtsi | 1 - 1 file changed, 1 deletion(-)
--- a/arch/arm64/boot/dts/renesas/ulcb.dtsi +++ b/arch/arm64/boot/dts/renesas/ulcb.dtsi @@ -145,7 +145,6 @@ &avb { pinctrl-0 = <&avb_pins>; pinctrl-names = "default"; - renesas,no-ether-link; phy-handle = <&phy0>; status = "okay";