Re: [PATCH v1 1/2] driver core: fw_devlink: Add support for FWNODE_FLAG_BROKEN_PARENT

Andrew Lunn
2021-09-30T13:15:22Z

On Wed, Sep 29, 2021 at 10:33:16PM -0700, Saravana Kannan wrote:
> On Tue, Aug 31, 2021 at 4:18 PM Vladimir Oltean <olteanv@gmail.com> wrote:
> >
> > On Wed, Sep 01, 2021 at 01:02:09AM +0200, Andrew Lunn wrote:
> > > Rev B is interesting because switch0 and switch1 got genphy, while
> > > switch2 got the correct Marvell PHY driver. switch2 PHYs don't have
> > > interrupt properties, so don't loop back to their parent device.
> >
> > This is interesting and not what I really expected to happen. It goes to
> > show that we really need more time to understand all the subtleties of
> > device dependencies before jumping on patching stuff.
> >
> > In case the DSA tree contains more than one switch, different things
> > will happen in dsa_register_switch().
> > The tree itself is only initialized when the last switch calls
> > dsa_register_switch(). All the other switches just mark themselves as
> > present and exit probing early. See this piece of code in dsa_tree_setup:
> >
> > complete = dsa_tree_setup_routing_table(dst);
> > if (!complete)
> > return 0;
>
> Hi Vladimir,
>
> Can you point me to an example dts file that has a DSA tree with more
> than one switch and also point me to the switches that form the tree?
>
> I'm working on a RFC series that tries to improve some stuff and
> having an example DTS to look at would help.

Some of the Zodiac boards have multiple switches. They are all Marvell
switches, using the mv88e6xxx driver.

arch/arm/boot/dts/vf610-zii-dev-rev-b.dts
arch/arm/boot/dts/vf610-zii-dev-rev-c.dts
arch/arm/boot/dts/vf610-zii-scu4-aib.dts

Andrew