Re: [PATCH v3 3/3] net: phy: dp83867: Recover from "port mirroring" N/A MODE4

From: Andrew Lunn
Date: Tue Feb 07 2017 - 08:04:19 EST


On Tue, Feb 07, 2017 at 06:20:24AM +0100, Lukasz Majewski wrote:
> The DP83867 when not properly bootstrapped - especially with LED_0 pin -
> can enter N/A MODE4 for "port mirroring" feature.
>
> To provide normal operation of the PHY, one needs not only to explicitly
> disable the port mirroring feature, but as well stop some IC internal
> testing (which disables RGMII communication).
>
> To do that the STRAP_STS1 (0x006E) register must be read and RESERVED bit
> 11 examined. When it is set, the another RESERVED bit (11) at PHYCR
> (0x0010) register must be clear to disable testing mode and enable RGMII
> communication.
>
> Thorough explanation of the problem can be found at following e2e thread:
> "DP83867IR: Problem with RESERVED bits in PHY Control Register (PHYCR) -
> Linux driver"
>
> https://e2e.ti.com/support/interface/ethernet/f/903/p/571313/2096954#2096954
>
> Signed-off-by: Lukasz Majewski <lukma@xxxxxxx>

Reviewed-by: Andrew Lunn <andrew@xxxxxxx>

Andrew