sanosis:

The gigabit port works on 17.01.2 when connected to fast ethernet but when connected to gigabit switch the speed is negotiated as GBit, the switch sees the mac of 1166, but no correct packets are sent (at least I can't see any with tcpdump on the other end), but something is being sent, as counters both on the switch and 1166 go up.

andapanda:

Workaround is as simple as reverting [[https://dev.openwrt.org/changeset/47346/trunk/target/linux/ramips/mt7620/config-3.18|this post-CC change.]] Just add a #. So either the IP1001 phy driver is broken, or it's changing something that is correct by default or bootloader setup to something incorrect for this router.

Why was the driver added in the first place? It works fine with the generic driver. [[https://lists.openwrt.org/pipermail/openwrt-devel/2015-October/036807.html|A post on the OpenWRT mailing list]] indicates the only gain is APS support, but [[http://www.icplus.com.tw/data/datasheet/ip1001_ds_r17_20101013.pdf|page 24 on the datasheet]] says it's already enabled by default.

In the icplus.c init, in addition to setting APS, it also appears to set the RGMII delay mode. This is also not done by the generic driver. Datasheet page 37 says these are initialized by pins at poweron. Overwriting this with the wrong value could explain the problem.

If that's the problem, then a better fix could be setting phy-mode to rgmii-id or rgmii-rxid in the dts. Unfortunately this probably will not work because I can not find anything similar to [[https://patchwork.kernel.org/patch/9152099/|this patch.]] The comments there seem to support my theory. Another fix could be making icplus.c respect the hardware configuration, but this would affect many more devices. The bad software design is probably to make up for bad hardware design somewhere else on some other architecture.

mkresin:

First of all, excellent bug report and analysis of the issue.

Why was the driver added in the first place?

Most likely because the phy driver is required to change the chip defaults RGMII delay mode settings.

If that's the problem, then a better fix could be setting phy-mode to rgmii-id or rgmii-rxid in the dts

Would you please give the images from https://www.kresin.me/files/lede-17.01.2/targets/ramips/mt7620/ a try. One of them should fix the issue and I need to know which it is. The images should be completely compatible to the official LEDE 17.01.2 release.

lippi:

Just tried all three of your images, and the -rxid seems to fix the problem.