On 7/27/24 04:07, Andrew Lunn wrote:
On Sat, Jul 27, 2024 at 11:25:25AM +0200, Krzysztof Kozlowski wrote:
On 27/07/2024 11:20, Frank.Sae wrote:
The motorcomm phy (yt8821) supports the ability to
config the chip mode of serdes.
The yt8821 serdes could be set to AUTO_BX2500_SGMII or
FORCE_BX2500.
In AUTO_BX2500_SGMII mode, SerDes
speed is determined by UTP, if UTP link up
at 2.5GBASE-T, SerDes will work as
2500BASE-X, if UTP link up at
1000BASE-T/100BASE-Tx/10BASE-T, SerDes will work
as SGMII.
In FORCE_BX2500, SerDes always works
as 2500BASE-X.
When the SERDES is forced to 2500BaseX, does it perform rate
adaptation? e.g. does it insert pause frames to slow down the MAC?
Maybe look at air_en8811h.c.
Andrew
Yes, when the serdes is forced to 2500base-x, it inserts pause frames to
perform rate adaptation to slow down the MAC.
