On 10/29/23 20:45, Andrew Lunn wrote:
> On Sun, Oct 29, 2023 at 06:27:11AM +0200, Cristian Ciocaltea wrote:
>> The StarFive VisionFive V1 SBC has a Motorcomm YT8521 PHY supporting
>> RGMII-ID, but requires manual adjustment of the RX internal delay to
>> work properly.
>>
>> The default RX delay provided by the driver is 1.95 ns, which proves to
>> be too high. Applying a 50% reduction seems to mitigate the issue.
>
> I'm not so happy this cannot be explained. You are potentially heading
> into horrible backwards compatibility problems with old DT blobs and
> new kernels once this is explained and fixed.
It seems the visionfive-v2 board also required setting some delays, but
unfortunately no details were provided:
0104340a67b1 ("riscv: dts: starfive: visionfive 2: Add configuration of
mac and phy")
Thanks,
Cristian
