Some rockchip boards have issues with tx checksumming for packets larger than 1498 B. An iperf test will tell you that transmissions stop almost immediately. A workaround to this issue is disabling TX checksumming offload, and one of the ways to do that is snps,force_thresh_dma_mode. But after some discussion here it seems there is another path: https://lkml.org/lkml/2019/4/5/148 Setting txpbl is a better-performing (maybe temporary) solution compared to disabling T offload. In my testing with a Libre Computer Renegade, this was the best all-around option, and increasing the MTU doesn't cause a queue timeout anymore. Signed-off-by: Leonidas P. Papadakos <papadakospan@xxxxxxxxx> --- arch/arm64/boot/dts/rockchip/rk3328-roc-cc.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/rockchip/rk3328-roc-cc.dts b/arch/arm64/boot/dts/rockchip/rk3328-roc-cc.dts index 5d499c908..974f2dcdf 100644 --- a/arch/arm64/boot/dts/rockchip/rk3328-roc-cc.dts +++ b/arch/arm64/boot/dts/rockchip/rk3328-roc-cc.dts @@ -141,10 +141,10 @@ phy-mode = "rgmii"; pinctrl-names = "default"; pinctrl-0 = <&rgmiim1_pins>; - snps,force_thresh_dma_mode; snps,reset-gpio = <&gpio1 RK_PC2 GPIO_ACTIVE_LOW>; snps,reset-active-low; snps,reset-delays-us = <0 10000 50000>; + snps,txpbl = <0x4>; tx_delay = <0x24>; rx_delay = <0x18>; status = "okay"; -- 2.21.0
