Re: [net-next: PATCH v3 5/6] net: mvpp2: enable using phylink with ACPI

Hi,

śr., 23 cze 2021 o 22:37 Andrew Lunn [off-list ref] napisał(a):

quoted

+static bool mvpp2_use_acpi_compat_mode(struct fwnode_handle *port_fwnode)
+{
+     if (!is_acpi_node(port_fwnode))
+             return false;
+
+     return (!fwnode_property_present(port_fwnode, "phy-handle") &&
+             !fwnode_property_present(port_fwnode, "managed") &&
+             !fwnode_get_named_child_node(port_fwnode, "fixed-link"));

I'm not too sure about this last one. You only use fixed-link when
connecting to an Ethernet switch. I doubt anybody will try ACPI and a
switch. It has been agreed, ACPI is for simple hardware, and you need
to use DT for advanced hardware configurations.

What is your use case for fixed-link?

Regardless of the "simple hardware" definition or whether DSA + ACPI
feasibility, you can still have e.g. the switch left in "unmanaged"
mode (or whatever the firmware configures), connected via fixed-link
to the MAC. The same effect as booting with DT, but not loading the
DSA/switch driver - the "CPU port" can be used as a normal netdev
interface.

I'd also prefer to have all 3 major interface types supported in
phylink, explicitly checked in the driver - it has not been supported
yet, but can be in the future, so let's have them covered in the
backward compatibility check.

Best regards,
Marcin