I improved the dts of Phicomm N1 again.
The reasons are:
1. The Ethernet card of N1 is not very compatible with some switches. When the ethernet phy is activated, the flow control sometimes cannot be turned on, so will get bad results during the speedtest.net . For this reason, I added a dts separately force_thresh_dma_mode, which is equivalent to flow control in software mode. But there are also side effects: tx performance is reduced. In addition, as auxiliary optimization items, set snps, aal; snps, txpbl = <0x8>; snps, rxpbl = <0x4>; their role is to improve the performance of the network card.
2. The phy reset-delay-us value of N1 is sometimes not enough. When running openwrt, sometimes the ethernet phy cannot be enabled, so the reset-delay-us value is increased.
Provide two dts files:
meson-gxl-s905d-phicomm-n1.dts: This is the default dts, used in most occasions, when the flow control can be turned on normally, this is the best choice
meson-gxl-s905d-phicomm-n1-thresh.dts: This is a dts with the force_thresh_dma_mode option enabled. It is applicable when flow control cannot be turned on. You can use force_thresh_dma_mode to control flow at the cost of a small amount of performance loss.
meson-gxl-s905d-phicomm-n1.dts
meson-gxl-s905d-phicomm-n1-thresh.dts