On Thu, Nov 23, 2023 at 3:15 AM Andrew Lunn <andrew@xxxxxxx> wrote: > > > + They feature 2 SerDes, one for PSGMII or QSGMII connection with > > + MAC, while second one is SGMII for connection to MAC or fiber. > > Can you connect 1/5 of the PSGMII SERDES to the SGMII SERDES? So > making use of the PHY as a media converter to connect to an SFP cage? > I assume the SGMII serdes can also do 1000BaseX? > > How do you describe what the SGMII SERDES is connected to? Hi Andrew, I think that the description is confusing. QCA807x supports 3 different modes: 1. PSGMII (5 copper ports) 2. PSGMII (4 copper ports + 1 combo port) 3. QSGMII+SGMII So, in case option 2 is selected then the combo port can also be used for 1000Base-X and 100Base-FX modules or copper and it will autodetect the exact media. This is supported via the SFP op-s and I have been using it without issues for a while. I have not tested option 3 in combination with SFP to the copper module so I cant say whether that works. >From what I can gather from the typical usage examples in the datasheet, this QSMII+SGMII mode is basically intended as a backward compatibility thing as only QCA SoC-s have PSGMII support so that you could still use SoC-s with QSGMII and SGMII support only. So there is no way to control the SerDes-es individually, only the global mode can be changed via the Chip configuration register in the Combo port. You can see the block diagram of this PHY in this public PDF on page 2[1]. [1] https://content.codico.com/fileadmin/media/download/datasheets/qualcomm/qualcomm_qca8075.pdf > > Andrew > -- Robert Marko Staff Embedded Linux Engineer Sartura Ltd. Lendavska ulica 16a 10000 Zagreb, Croatia Email: robert.marko@xxxxxxxxxx Web: www.sartura.hr
