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Message-Id: <20191114.150900.1936363085147930639.davem@davemloft.net>
Date: Thu, 14 Nov 2019 15:09:00 -0800 (PST)
From: David Miller <davem@...emloft.net>
To: olteanv@...il.com
Cc: f.fainelli@...il.com, vivien.didelot@...il.com, andrew@...n.ch,
vinicius.gomes@...el.com, richardcochran@...il.com,
netdev@...r.kernel.org
Subject: Re: [PATCH net-next 0/2] PTP clock source for SJA1105 tc-taprio
offload
From: Vladimir Oltean <olteanv@...il.com>
Date: Tue, 12 Nov 2019 02:11:52 +0200
> This series makes the IEEE 802.1Qbv egress scheduler of the sja1105
> switch use a time reference that is synchronized to the network. This
> enables quite a few real Time Sensitive Networking use cases, since in
> this mode the switch can offer its clients a TDMA sort of access to the
> network, and guaranteed latency for frames that are properly scheduled
> based on the common PTP time.
>
> The driver needs to do a 2-part activity:
> - Program the gate control list into the static config and upload it
> over SPI to the switch (already supported)
> - Write the activation time of the scheduler (base-time) into the
> PTPSCHTM register, and set the PTPSTRTSCH bit.
> - Monitor the activation of the scheduler at the planned time and its
> health.
>
> Ok, 3 parts.
>
> The time-aware scheduler cannot be programmed to activate at a time in
> the past, and there is some logic to avoid that.
>
> PTPCLKCORP is one of those "black magic" registers that just need to be
> written to the length of the cycle. There is a 40-line long comment in
> the second patch which explains why.
Series applied to net-next, thank you.
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