Hi Andrew, > From: Andrew Lunn, Sent: Friday, September 30, 2022 12:00 AM > > On Thu, Sep 29, 2022 at 12:22:15PM +0000, Yoshihiro Shimoda wrote: > > Hi Andrew, > > > > > From: Andrew Lunn, Sent: Wednesday, September 28, 2022 9:01 PM > > > > > > > > How do you direct a frame from the > > > > > CPU out a specific user port? Via the DMA ring you place it into, or > > > > > do you need a tag on the frame to indicate its egress port? > > > > > > > > Via the DMA ring. > > > > > > Are there bits in the ring descriptor which indicate the user port? > > > Can you set these bits to some other value which causes the switch to > > > use its MAC table to determine the egress interface? > > > > I'm sorry, I misunderstood the hardware behaviors. > > > > 1) From CPU to user port: CPU sends a frame to all user ports. > > 2) From user port to CPU: each user port sends a frame to each DMA ring. > > > > About the 1) above, the switch can have MAC tables and sends a frame to > > a specific user port. However, the driver doesn't support it. > > In order to make STP and PTP work, you need to be able to send a frame > out a specific port. With STP, that port can also be blocked, > i.e. normal frames are not allowed to be transmitted/received, but > these STP frames are allowed. You also need to know what port an STP > frame was received on. I understood it. > So the switch probably has a mechanism to send a frame from the CPU > out one specific port. And frames received from a user port and passed > to the CPU should also be identifiable. There are different ways of > doing this. DSA typically has an extra header on the frame, indicating > where it is from/to. Some switches have extra bits in the DMA buffer > descriptor indicating the port. I'll looking for such a feature in the switch. > > However, if I dropped specific registers setting, it doesn't work correctly. > > I'll investigate why removing speeds of PHY didn't work. > > It could be the PHY is using SGMII, but your MAC needs 1000BaseX? Both the PHY and MAC is using SGMII. For now, I didn't find why. So, I'll continue to investigate this issue too. Best regards, Yoshihiro Shimoda > Andrew
