From: Jiri Pirko <jiri@resnulli.us>
Sent: Saturday, June 10, 2023 6:37 PM

Fri, Jun 09, 2023 at 02:18:51PM CEST, arkadiusz.kubalewski@intel.com wrote:

[...]

quoted

+static int ice_dpll_mode_get(const struct dpll_device *dpll, void *priv,
+			     enum dpll_mode *mode,
+			     struct netlink_ext_ack *extack)
+{
+	*mode = DPLL_MODE_AUTOMATIC;

I don't understand how the automatic mode could work with SyncE. The
There is one pin exposed for one netdev. The SyncE daemon should select
exacly one pin. How do you achieve that?
Is is by setting DPLL_PIN_STATE_SELECTABLE on the pin-netdev you want to
select and DPLL_PIN_STATE_DISCONNECTED on the rest?


[...]

AUTOMATIC mode autoselects highest priority valid signal.
As you have pointed out, for SyncE selection, the user must be able to manually
select a pin state to enable recovery of signal from particular port.

In "ice" case there are 2 pins for network PHY clock signal recovery, and both
are parent pins (MUX-type). There are also 4 pins assigned to netdevs (one per
port). Thus passing a signal from PHY to the pin is done through the MUX-pin,
by selecting proper state on pin-parent pair (where parent pins is highest prio
pin on dpll).

Thank you!
Arkadiusz