Re: [PATCHv1 3/3] net: stmmac: dwmac-meson8b: Add reset controller for ethernet phy

From: Martin Blumenstingl
Date: Tue Aug 03 2021 - 16:45:29 EST


Hi Anand,

On Thu, Jul 29, 2021 at 10:11 PM Anand Moon <linux.amoon@xxxxxxxxx> wrote:
>
> Add reset controller for Ethernet phy reset on every boot for
> Amlogic SoC.
I think this description does not match what's going on inside the SoC:
- for all SoCs earlier than GXL the PHY is external so the reset for
the PHY is a GPIO
- the reset line you are passing in the .dts belongs to the Ethernet
controller on SoCs earlier than GXL
- I *believe* that the rset line which you're passing in the .dts
belongs to the Ethernet controller AND the built-in MDIO mux on GXL
and newer, see also [0]
- from how the PRG_ETH registers work I doubt that these are connected
to a reset line (as they're managing mostly delays and protocol - so I
don't see what would be reset). This is speculation though.


Best regards,
Martin


[0] https://lore.kernel.org/linux-amlogic/553e127c-9839-d15b-d435-c01f18c7be48@xxxxxxxxx/