Arria 10 HPS - DMA EMAC reset issue

Hello,

We are bring-up the custom Arria 10 board, we have some issue with HPS GMAC in U-Boot.

Arria 10 connect to SFP (1 G Ethernet) , our interface is :

HPS EMAC0 → FPGA GMII-to-SGMII Converter → SFP (SGMII PHY)

We are working without MDC/MDIO , in fixed mode.

During our testing we performed ping and after this we read register 0xFF801000 and we received value 0x00020101( Last bit DMA_BUS_MODE.SWR = 1 instead of the 0).

We checked :

1. The input clock of 125 MHz  by oscilloscope - looks ok.
2. Reset Manager:  0xFFD05024 = 0xFF7FBEBE (EMAC0 is released from reset).

3. Bridge is working.

4. GMII-to-SGMII registers are accessible

5.  Device tree addresses were verified agaonst the .sopcinfo file

Looking forward to your response, thanks in advance.