[参考译文] AM5716：PRU-ETH 不可用、无法发送/接收任何数据包。

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1418179/am5716-pru-eth-unavailable-can-not-send-recv-any-packet

工具与软件：

您好、TI 专家：

我在 DSP 上运行 SYS/BIOS、使用 PRU-ETH 发送/接收数据包、并使用 IPC 与 A15内核(运行 A15中 Linux 的主机)进行通信。 在某些情况下、当 PRU-ETH 变得不可用时、就会出现问题：它无法再发送或接收任何数据包。 不过、当我调用该函数时

int32_t ICSS_EmacTxPacket(const ICSS_EmacTxArgument *txArg, void* userArg)

触发此问题的一个已确认的行为是在主机程序和 DSP 程序正常运行：的情况下执行命令

echo 40800000.dsp > /sys/bus/platform/drivers/omap-rproc/unbind
echo 40800000.dsp > /sys/bus/platform/drivers/omap-rproc/bind

会触发"Bug"。

我进行了以下测试：

```bash
root@SunGrow:~# ifconfig eth3 down
[ 4695.832319] prueth pruss2_eth eth3: Link is Down
[ 4695.863972] pruss 4b280000.pruss: unconfigured system_events[63-0] = 00600000,08a00000
[ 4695.879840] pruss 4b280000.pruss: unconfigured host_intr = 0x000002aa
[ 4695.892873] remoteproc remoteproc3: stopped remote processor 4b2b8000.pru
[ 4695.908040] net eth3: stopped
root@SunGrow:~# ifconfig eth3 up
[ 4708.931205] remoteproc remoteproc3: powering up 4b2b8000.pru
[ 4710.965959] remoteproc remoteproc3: loading /lib/firmware/ti-pruss/am57xx-pru1-prueth-fw.elf successfully!    drivers/base/firmware_loader/main.c L349
[ 4710.993076] remoteproc remoteproc3: Booting fw image ti-pruss/am57xx-pru1-prueth-fw.elf, size 6952
[ 4711.012099] pruss 4b280000.pruss: configured system_events[63-0] = 00600000,08a00000
[ 4711.028863] pruss 4b280000.pruss: configured intr_channels = 0x0000032a host_intr = 0x000002aa
[ 4711.048084] remoteproc remoteproc3: remote processor 4b2b8000.pru is now up
[ 4711.076954] net eth3: started
[ 4711.080389] IPv6: ADDRCONF(NETDEV_UP): eth3: link is not ready
[ 4711.089853] prueth pruss2_eth eth3: drivers/net/phy/phy.c L74 Link is Up-- - 100Mbps/Full - flow control off
[ 4711.114863] 8021q: adding VLAN 0 to HW filter on device eth3
[ 4711.126955] IPv6: ADDRCONF(NETDEV_CHANGE): eth3: link becomes ready
root@SunGrow:~# ethtool -S eth3
NIC statistics:
     txBcast: 0
     txMcast: 0
     txUcast: 0
     txOctets: 0
     rxBcast: 0
     rxMcast: 0
     rxUcast: 0
     rxOctets: 0
     tx64byte: 0
     tx65_127byte: 0
     tx128_255byte: 0
     tx256_511byte: 0
     tx512_1023byte: 0
     tx1024byte: 0
     rx64byte: 0
     rx65_127byte: 0
     rx128_255byte: 0
     rx256_511byte: 0
     rx512_1023byte: 0
     rx1024byte: 0
     lateColl: 0
     singleColl: 0
     multiColl: 0
     excessColl: 0
     rxMisAlignmentFrames: 0
     stormPrevCounterBC: 0
     stormPrevCounterMC: 0
     stormPrevCounterUC: 0
     macRxError: 1
     SFDError: 0
     defTx: 0
     macTxError: 0
     rxOverSizedFrames: 0
     rxUnderSizedFrames: 0
     rxCRCFrames: 0
     droppedPackets: 0
     txHWQOverFlow: 0
     txHWQUnderFlow: 0
     emacMulticastDropped: 0
     emacVlanDropped: 0
```

然后我将 eth3连接到笔记本电脑的以太网端口、用工具向 eth3发送数据包。 Wireshark 捕获如下：

但是、当ethtool -S eth3再次使用时、我得到相同的结果。