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

Vladimir Oltean
2021-09-30T13:44:11Z

Hi Saravana,

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.
>
> Thanks,
> Saravana

Andrew is testing with arch/arm/boot/dts/vf610-zii-dev-rev-b.dts.

Graphically it looks like this:

+-----------------------------+
| VF610 SoC |
| +--------+ |
| | fec1 | |
+----------+--------+---------+
| DSA master
|
| ethernet = <&fec1>;
+--------+----------+---------------------------+
| | port@6 | |
| +----------+ |
| | CPU port | dsa,member = <0 0>; |
| +----------+ -> tree 0, switch 0 |
| | cpu | |
| +----------+ |
| |
| switch0 |
| |
+-----------+-----------+-----------+-----------+
| port@0 | port@1 | port@2 | port@5 |
+-----------+-----------+-----------+-----------+
|switch0phy0|switch0phy1|switch0phy2| no PHY |
+-----------+-----------+-----------+-----------+
| user port | user port | user port | DSA port |
+-----------+-----------+-----------+-----------+
| lan0 | lan1 | lan2 | dsa |
+-----------+-----------+-----------+-----------+
| link = <&switch1port6 &switch2port9>;
|
|
|
| link = <&switch0port5>;
+----------+----------+-------------------------+
| | port@6 | |
| +----------+ |
| | DSA port | dsa,member = <0 1>; |
| +----------+ -> tree 0, switch 1 |
| | dsa | |
| +----------+ |
| |
| switch1 |
| |
+-----------+-----------+-----------+-----------+
| port@0 | port@1 | port@2 | port@5 |
+-----------+-----------+-----------+-----------+
|switch1phy0|switch1phy1|switch2phy2| no PHY |
+-----------+-----------+-----------+-----------+
| user port | user port | user port | DSA port |
+-----------+-----------+-----------+-----------+
| lan3 | lan4 | lan5 | dsa |
+-----------+-----------+-----------+-----------+
| link = <&switch2port9>;
|
|
|
| link = <&switch1port5 &switch0port5>;
+----------+----------+-------------------------------------+
| | port@9 | |
| +----------+ |
| | DSA port | dsa,member = <0 2>; |
| +----------+ -> tree 0, switch 2 |
| | dsa | |
| +----------+ |
| |
| switch2 |
| |
+-----------+-----------+-----------+-----------+-----------+
| port@0 | port@1 | port@2 | port@3 | port@4 |
+-----------+-----------+-----------+-----------+-----------+
|switch2phy0|switch2phy1|switch2phy2| no PHY | no PHY |
+-----------+-----------+-----------+-----------+-----------+
| user port | user port | user port | user port | user port |
+-----------+-----------+-----------+-----------+-----------+
| lan6 | lan7 | lan8 | optical3 | optical4 |
+-----------+-----------+-----------+-----------+-----------+