Re: [PATCH net v1 1/2] net: dsa: microchip: fix devicetree parsing of cpu node

On Tue, Dec 8, 2020 at 11:52 AM Jakub Kicinski [off-list ref] wrote:

What I was talking about in the email yesterday was 0x8794 support
in ksz8795.c. Is the cpu port configuration going to work there?
Isn't the CPU port always port 5 (index 4)?

Understood. You expressed concern that .cpu_ports = 0x10 even on the 3-port
switch.

I noticed that .cpu_ports is never used in ksz8794.c, so I hoped the fix
would be fine. But digging a bit deeper, I see in ksz8795.c:

        dev->mib_port_cnt = TOTAL_PORT_NUM; /* = 5 */
        ...
        dev->cpu_port = dev->mib_port_cnt - 1; /* = 4 */

And that is unlikely to work on the 3-port switch.
So yeah, you are right, my patch won't fix the general issues here :(