On Mon, Feb 16, 2026 at 04:44:27AM +0000, Yao Zi wrote:

On Fri, Feb 13, 2026 at 06:47:14PM +0000, Russell King (Oracle) wrote:

quoted

On Fri, Feb 13, 2026 at 06:26:44PM +0000, Yao Zi wrote:

quoted

Hi folks,

I was looking through the RGMII delay setup logic found in
rk_gmac_powerup() of dwmac-rk.c, and found its behavior is strange,

dwmac-rk is very broken and is unfixable thanks to Rockchip not
understanding the RGMII interface modes used by the kernel.

It is what it is, we can't change it without causing regressions.
Please do not try to fix it.

Thanks for confirming. I understand concerns about regressions and
agree keeping the driver/dts as-is is better.

However, should we mention the difference between "phy-mode" defined
ethernet-controller.yaml and "phy-mode" understood by dwmac-rk
driver in rockchip-dwmac.yaml to avoid confusion in the future?

I've been telling DT developers to set the correct phy-mode,
'rgmii-id', and the vendor properties for MAC delays to 0. That works,
and it consistent with the documentation.

As far as i know, dwmac-rk only gets things wrong when you try to get
the MAC to add the 2ns delays. And that is not a recommended
configuration. So i don't think it is too important to document a not
recommended configuration is broken.

	Andrew