[PATCH v4 2/2] ARM: imx6plus: enable internal routing of clk_enet_ref where possible

Fabio Estevam festevam at gmail.com
Mon Jun 29 09:09:59 EDT 2020

Hi Sven,

On Thu, Jun 25, 2020 at 11:01 AM Sven Van Asbroeck <thesven73 at gmail.com> wrote:
> On imx6, the ethernet reference clock (clk_enet_ref) can be generated
> by either the imx6, or an external source (e.g. an oscillator or the
> PHY). When generated by the imx6, the clock source (from ANATOP)
> must be routed to the input of clk_enet_ref via two pads on the SoC,
> typically via a dedicated track on the PCB.
> On an imx6 plus however, there is a new setting which enables this
> clock to be routed internally on the SoC, from its ANATOP clock
> source, straight to clk_enet_ref, without having to go through
> the SoC pads.
> Board designs where the clock is generated by the imx6 should not
> be affected by routing the clock internally. Therefore on a plus,
> we can enable internal routing by default.
> Signed-off-by: Sven Van Asbroeck <TheSven73 at gmail.com>

I have tested this series on an imx6qp sabresd and unfortunately, it
breaks Ethernet as I can no longer get an IP address from the DHCP

Without this series, IP address can normally be retrieved.

Therefore I suggest to create a device tree property for this feature
and only enable it when such device tree property is present.

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