is there a bug in the Ethernet MAC of Arria10 SoC devices?

Hi Eberlazare,

Thanks for your feedback.

This issue is not observed in u-boot but on a running Linux. Our hardware has only one Ethernet connection which use EMAC1 (EMAC0 is disabled). In the Linux device tree the EMAC1 configuration is connected to ethernet0 (aliases section) which result in the naming eth0 on Linux.

Bellow you find the Linux device tree entry for the ethernet configuration.

Do you think there is something wrong? Or what could be the reason for this high Ethernet latency?

hps_gmac: ethernet@ff802000 {
	compatible = "altr,socfpga-stmmac", "snps,dwmac-3.72a", "snps,dwmac";
	altr,sysmgr-syscon = <&sysmgr 0x48 8>;
	reg = <0xff802000 0x2000>;
	interrupts = <0 93 4>;
	interrupt-names = "macirq";
	/* Filled in by bootloader */
	mac-address = [00 00 00 00 00 00];
	snps,multicast-filter-bins = <256>;
	snps,perfect-filter-entries = <128>;
	snps,axi-config = <&socfpga_axi_setup>;
	tx-fifo-depth = <4096>;
	rx-fifo-depth = <16384>;

	clocks = <&l4_mp_clk>, <&peri_emac_ptp_clk>;
	clock-names = "stmmaceth", "ptp_ref";

	resets = <&rst 33>, <&rst 41>;
	reset-names = "stmmaceth", "stmmaceth-ocp";
		
	phy-mode = "rgmii-id";
	max-frame-size = <3800>;
	/* probe for phy addr */
	phy-addr = <0xffffffff>;

	txd0-skew-ps = <420>; /* 0ps */
	txd1-skew-ps = <420>; /* 0ps */
	txd2-skew-ps = <420>; /* 0ps */
	txd3-skew-ps = <420>; /* 0ps */
	rxd0-skew-ps = <420>; /* 0ps */
	rxd1-skew-ps = <420>; /* 0ps */
	rxd2-skew-ps = <420>; /* 0ps */
	rxd3-skew-ps = <420>; /* 0ps */
	txen-skew-ps = <420>; /* 0ps */
	rxdv-skew-ps = <420>; /* 0ps */
	txc-skew-ps = <1440>; /* 540ps */
	rxc-skew-ps = <1680>; /* 780ps */

	status = "okay";
};