[PATCH 0/3] arm64: dts: rockchip: Change gmac phy-mode to rgmii-id for rk3576 board

[Chaoyi Chen]

Hi Andrew,

On 1/21/2026 8:57 PM, Andrew Lunn wrote:
> On Wed, Jan 21, 2026 at 11:15:45AM +0800, Chaoyi Chen wrote:
>> From: Chaoyi Chen <chaoyi.chen at rock-chips.com>
>>
>> According to the description in the net documentation, PHY modes
>> "rgmii", "rgmii-rxid" and "rgmii-txid" modes require the clock signal
>> to be delayed on the PCB.
>>
>> The Rockchip platform has long used the above mentioned PHY modes and
>> private delay prop to describe the internal IO delay settings of the
>> chip, which is inconsistent with what is described in the documentation.
>>
>> Some background, for RK3576, you can assume that:
>>
>>         tx_delay_time(ns) = 0.0579 * delay_line_count + 0.105
> 
> Where did this formula come from? Is it in the datasheet.
> 

These are measured values obtained from hardware signal testing.
They are not documented in the TRM.

-- 
Best, 
Chaoyi