In Table 5-10 of iMX7D RM, there is external signal CCM_ENET3_REF_CLK with following mux-mode:
Check GPIO1_IO01 pad muxmode, there is:
ALT2_CCM_ENET_REF_CLK3 — Select mux mode: ALT2 mux port: ENET_REF_CLK3 of instance: CCM
and GPIO1_IO09 pad muxmode:
ALT2_CCM_ENET_PHY_REF_CLK — Select mux mode: ALT2 mux port: ENET_PHY_REF_CLK of instance: CCM
and I2C2_SDA pad muxmode:
ALT4_CCM_ENET_PHY_REF_CLK — Select mux mode: ALT4 mux port: ENET_PHY_REF_CLK of instance: CCM
As my understanding, three different signal names represent the same signal, coresponding to IMX7D_ENET_PHY_REF_ROOT_DIV in DTS file. Is it right?