4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Bogdan Mirea <Bogdan-Stefan_Mirea@xxxxxxxxxx>
[ 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@xxxxxxxxxx>
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@xxxxxxxxxx>
Signed-off-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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";