Hi! On Thu, Oct 12, 2023 at 5:02 AM Randy Li via openwrt-devel <openwrt-devel@lists.openwrt.org> wrote: > Subject: [PATCH 1/2] ath79: correct switch PHYs for GMAC0 in ar934x > According to Ethernet Subsystem section of Functional Description > chapter of the datasheet, when GMAC0 connects to the internal > switch, it is MDC/MDIO of the GMAC0 decided which PHY it should > talk to.
The switch decides whether internal PHYs respond to direct PHY access from GMAC MDIO. If the switch built-in MDIO bus is enabled, all the PHYs only respond to switch MDIO requests and ignore the ones from GMAC MDIO. If u-boot enables switch MDIO (many vendor u-boot do so), PHYs defined in GMAC MDIO won't be discovered until a switch reset. Also, I vaguely remembered that the AR934X GMAC0 MDIO is always the external one and the built-in switch is on MDIO1. Have you tested this on existing devices? -- Regards, Chuanhong Guo _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/mailman/listinfo/openwrt-devel
