Re: [RFC PATCH v8 08/10] ice: implement dpll interface to control cgu

From: Jiri Pirko
Date: Wed Jun 21 2023 - 08:30:09 EST


Mon, Jun 19, 2023 at 10:34:12PM CEST, arkadiusz.kubalewski@xxxxxxxxx wrote:
>>From: Jiri Pirko <jiri@xxxxxxxxxxx>
>>Sent: Saturday, June 10, 2023 6:37 PM
>>
>>Fri, Jun 09, 2023 at 02:18:51PM CEST, arkadiusz.kubalewski@xxxxxxxxx wrote:
>>
>>[...]
>>
>>
>>>+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).

Could you show me some examples please?


>
>Thank you!
>Arkadiusz