No it is not possible (it will work if speed (and frequency) is fixed 25Mhz=100Mbps, but for speed 10Mbps (2,5MHz) it will not work.+static int stm32mp2_configure_syscfg(struct plat_stmmacenet_data *plat_dat)
+{
+ struct stm32_dwmac *dwmac = plat_dat->bsp_priv;
+ u32 reg = dwmac->mode_reg;
+ int val = 0;
+
+ switch (plat_dat->mac_interface) {
+ case PHY_INTERFACE_MODE_MII:
+ break;
dwmac->enable_eth_ck does not apply to MII mode ? Why ?
It is like MP1 and MP13, nothing to set in syscfg register for case MII mode wo crystal.
Have a look at STM32MP15xx RM0436 Figure 83. Peripheral clock distribution for Ethernet.
If RCC (top-left corner of the figure) generates 25 MHz MII clock (yellow line) on eth_clk_fb (top-right corner), can I set ETH_REF_CLK_SEL to position '1' and ETH_SEL[2] to '0' and feed ETH (right side) clk_rx_i input with 25 MHz clock that way ?
I seems like this should be possible, at least theoretically. Can you check with the hardware/silicon people ?
(you can see than diviser are only for RMII mode)