Re: MT7621 ethernet does not get probed on net-next branch after 5.15 merge

["Andrey Jr. Melnikov" <temnota.am@gmail.com>]

In gmane.comp.embedded.openwrt.devel Sergio Paracuellos <sergio.paracuellos@gmail.com> wrote:
> Hi Qingfang,

> On Fri, Oct 15, 2021 at 4:23 PM DENG Qingfang <dqfext@gmail.com> wrote:
> >
> > Hi,
> >
> > After the merge of 5.15.y into net-next, MT7621 ethernet
> > (mtk_eth_soc.c) does not get probed at all.
> >
> > Kernel log before 5.15 merge:
> > ...
> > libphy: Fixed MDIO Bus: probed
> > libphy: mdio: probed
> > mt7530 mdio-bus:1f: MT7530 adapts as multi-chip module
> > mtk_soc_eth 1e100000.ethernet eth0: mediatek frame engine at 0xbe100000, irq 20
> > mt7621-pci 1e140000.pcie: host bridge /pcie@1e140000 ranges:
> > ...
> >
> > Kernel log after 5.15 merge:
> > ...
> > libphy: Fixed MDIO Bus: probed
> > mt7621-pci 1e140000.pcie: host bridge /pcie@1e140000 ranges:
> > ...
> >
> >
> > I tried adding debug prints into the .mtk_probe function, but it did
> > not execute.
> > There are no dts changes for MT7621 between 5.14 and 5.15, so I
> > believe it should be something else.
> >
> > Any ideas?

> I had time to create a new image for my gnubee board using kernel 5.15
> and this problem does not exist on my side. Since no more mails have
> come for a while I guess this was a problem from your configuration,
> but just in case I preferred to answer to let you know. I am currently
> using v5.15.7 from linux-stable with some other patches that will be
> for 5.16. Just in case, you can check the kernel tree [0] I am
> currently using.

There is problem with reset controller and devlink commutication. reset
controller is abent in mainline, devlink defer all drivers which use reset
lines until reset-controller become available - so no drivers probed.
I'm create for myself this patch:
https://drive.google.com/file/d/1AiKlfvIgtrBsxtI-2XFBvaxGoE0S-s9d/view?usp=sharing