port-arm/53216: sunxi awge is unreliable at gigabit speed

[bouyer%antioche.eu.org@localhost]

>Number:         53216
>Category:       port-arm
>Synopsis:       sunxi awge is unreliable at gigabit speed
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    port-arm-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Apr 26 08:25:00 +0000 2018
>Originator:     Manuel Bouyer
>Release:        NetBSD 8.99.14
>Organization:
>Environment:
System: NetBSD lime2 8.99.14 NetBSD 8.99.14 (SUNXI_CAN) #21: Wed Apr 25 14:57:43 CEST 2018 bouyer%bip.soc.lip6.fr@localhost:/dsk/l1/misc/bouyer/tmp/evbarm-earmhf/obj/dsk/l1/misc/bouyer/HEAD/clean/src/sys/arch/evbarm/compile/SUNXI_CAN evbarm
Architecture: earmv7hf
Machine: evbarm

>Description:
	On a olimex Lime2 board with:
awge0 at fdt1 (/soc@1c00000/ethernet@1c50000)fdt: [ethernet@1c50000] decoded addr #0: 1c50000 -> 1c50000
: GMAC
awge0: interrupting on GIC irq 117
awge0: Ethernet address: 02:c7:04:82:c2:37
rgephy0 at awge0 phy 0: RTL8169S/8110S/8211 1000BASE-T media interface, rev. 5
rgephy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseT, 1000baseT-FDX, auto
rgephy1 at awge0 phy 1: RTL8169S/8110S/8211 1000BASE-T media interface, rev. 5
rgephy1: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseT, 1000baseT-FDX, auto
awge0: WARNING: power management not supported

	(note that the PHY attaches twice), the network is sometimes
	unreliable. When connected to a 100Mbs cisco switch everything
	works fine. When connected to a 1Gbs dlink switch, the green led
	on the board's ethernet connector (link state) flashes at about
	1s and there are packet loss:
100 packets transmitted, 96 packets received, 4.0% packet loss
round-trip min/avg/max/stddev = 0.286974/1.172346/10.286504/2.295635 ms
	(scp also has much lower speed than it should).
	The link on the switch side, and in ifconfig output doens't
	show this down/up problem.
	While the green led is off on the board's ethenet connector, the
	yellow led (link activity) seems to still be flashing as usual.
	Also, the ping's packet loss doens't reflect the led off/on ratio.

>How-To-Repeat:
	connect a lime2 to a 1Gbs switch
>Fix:
	unknown