于 2020年10月25日 GMT+08:00 下午10:18:25, Andrew Lunn <and...@lunn.ch> 写到:
>On Sun, Oct 25, 2020 at 04:55:56PM +0800, Icenowy Zheng wrote:
>> Currently there are many boards that just set "rgmii" as phy-mode in
>the
>> device tree, and leave the hardware [TR]XDLY pins to set PHY delay
>mode.
>>
>> In order to keep old device tree working, omit setting delay for just
>> "RGMII" without any internal delay suffix, otherwise many devices are
>> broken.
>
>Hi Icenowy
>
>We have been here before with the Atheros PHY. It did not correctly
>implement one of the delay modes, until somebody really did need that
>mode. So the driver was fixed. And we then found a number of device
>trees were also buggy. It was painful for a while, but all the device
>trees got fixed.
1. As the PHY chip has hardware configuration for configuring delays,
we should at least have a mode that respects what's set on the hardware.
2. As I know, at least Fedora ships a device tree with their bootloader, and
the DT will not be updated with kernel. This enforces compatibility
with old DTs even if they're broken.
Personally I think if someone wants a mode that explicitly disable delays
in the PHY, a new mode may be created now, maybe called "rgmii-noid".
>
>We should do the same here. Please submit patches for the device tree
>files.
>
> Andrew
--
You received this message because you are subscribed to the Google Groups
"linux-sunxi" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to linux-sunxi+unsubscr...@googlegroups.com.
To view this discussion on the web, visit
https://groups.google.com/d/msgid/linux-sunxi/77AAA8B8-2918-4646-BE47-910DDDE38371%40aosc.io.
