Re: [PATCH net-next RFC 2/9] net: dsa: mv88e6xxx: expose switch time as a PTP hardware clock

Andrew Lunn
2017-09-28T16:56:43Z

On Thu, Sep 28, 2017 at 10:25:34AM -0500, Brandon Streiff wrote:
> This patch adds basic support for exposing the 32-bit timestamp counter
> inside the mv88e6xxx switch code as a ptp_clock.
>
> Signed-off-by: Brandon Streiff <brandon.streiff@ni.com>
> ---
> drivers/net/dsa/mv88e6xxx/Kconfig | 10 +++
> drivers/net/dsa/mv88e6xxx/Makefile | 1 +
> drivers/net/dsa/mv88e6xxx/chip.c | 20 +++++
> drivers/net/dsa/mv88e6xxx/chip.h | 16 ++++
> drivers/net/dsa/mv88e6xxx/ptp.c | 180 +++++++++++++++++++++++++++++++++++++
> drivers/net/dsa/mv88e6xxx/ptp.h | 83 +++++++++++++++++
> 6 files changed, 310 insertions(+)
> create mode 100644 drivers/net/dsa/mv88e6xxx/ptp.c
> create mode 100644 drivers/net/dsa/mv88e6xxx/ptp.h
>
> diff --git a/drivers/net/dsa/mv88e6xxx/Kconfig b/drivers/net/dsa/mv88e6xxx/Kconfig
> index 1aaa7a9..ae9e7f7 100644
> --- a/drivers/net/dsa/mv88e6xxx/Kconfig
> +++ b/drivers/net/dsa/mv88e6xxx/Kconfig
> @@ -18,3 +18,13 @@ config NET_DSA_MV88E6XXX_GLOBAL2
>
> It is required on most chips. If the chip you compile the support for
> doesn't have such registers set, say N here. In doubt, say Y.
> +
> +config NET_DSA_MV88E6XXX_PTP
> + bool "PTP support for Marvell 88E6xxx"
> + default n
> + depends on NET_DSA_MV88E6XXX_GLOBAL2
> + imply NETWORK_PHY_TIMESTAMPING

Hi Brandon

Cool to see this code.

One probably dumb question so far..

It is the MAC which is doing the time stamping, not they PHY?
So why NETWORK_PHY_TIMESTAMPING?

Andrew