Re: [PATCH v2] net/phy/vitesse: Configure RGMII skew on VSC8601, if needed

From: David Miller
Date: Wed Nov 16 2016 - 17:54:30 EST

From: Alexandru Gagniuc <alex.g@xxxxxxxxxxxx>
Date: Wed, 16 Nov 2016 01:02:33 -0800

> With RGMII, we need a 1.5 to 2ns skew between clock and data lines. The
> VSC8601 can handle this internally. While the VSC8601 can set more
> fine-grained delays, the standard skew settings work out of the box.
> The same heuristic is used to determine when this skew should be enabled
> as in vsc824x_config_init().
> Tested on custom board with AM3352 SOC and VSC801 PHY.
> Signed-off-by: Alexandru Gagniuc <alex.g@xxxxxxxxxxxx>
> ---
> Changes since v1:
> * Added comment detailing applicability to different RGMII interfaces.