RE: [PATCH net-next v2 0/2] net: phy: Add Maxio MAE0621A support

[刘 昌杰]

Hi Andrew,

I checked the schematics and tested the broadcast control on an LCKFB Taishan Pi 3M (which has an MAE0621A-Q3C at PHY address 1, ID 0x7b744412).

For the RGMII delays, pin 24 (RXD1/TXDLY) is pulled down (4.7k) and pin 25 (RXD0/RXDLY) is pulled up (4.7k). So the hardware straps are TXDLY=0 and RXDLY=1. Per Table 7-3 in the datasheet, this disables the TX delay and enables a 2ns RX delay. This matches the DT using `phy-mode="rgmii-rxid"` and the RK3576 GMAC `tx_delay=<0x24>`. (I haven't scoped the actual clock skew or found a register that exposes the latched strap values, though).

For the broadcast test: initially, PHYCR1 (page 0xa43, reg 0x18) was 0x2118 (bit 13 set). Reading the PHY ID from both addr 0 and 1 returned 0x7b744412. After clearing bit 13 on addr 1, addr 0 stopped responding (returned 0xffff), while addr 1 kept working. I didn't send any writes to addr 0.

This state survived a BMCR soft reset―PHYCR1 stayed at 0x0118 and addr 0 stayed dead. (Note: I did this via MDIO ioctls on the board's 7.1.0-rc2 kernel, not against the new v3 series. The vendor driver doesn't touch the broadcast disable bit. I haven't tested power cycle persistence or the Q2C variant).

With broadcast disabled, the link came back up at 1000/Full after soft resets and physical cable replugs. Ping and a 10-second iperf3 run were perfectly clean (~941 Mbit/s). Writing the original value back to PHYCR1 brought addr 0 back to life.

Also, a quick heads up: patch 2/5 in the v3 series still carries your withdrawn Reviewed-by tag.