TMDX654IDKEVM: No Tx traffic with PRU-ICSSG on MII mode

Lukas Libal1

Part Number: TMDX654IDKEVM

Hello,

I am working on IDK board with PHYs on MII. My issue is that the interface does not transmit any frame.
The receiving works, tcpdump capture valid received frames.
Also for received ARP frame system generates corresponding ARP response, which is in capture also, but is not transmitted on the line.

Used versions

TMDX654IDKEVM - PROCA with PG2.1
SDK - PROCESSOR-SDK-LINUX-RT-AM65X 08.02.00.01
GCC - gcc-arm-9.2-2019.12-x86_64-aarch64-none-linux-gnu
PinMuxTool - last available cloud version

Changes which are done

1. HW changes - EVM User's guide (www.ti.com/.../spruim6)
- Applied all changes according to chapter 7.1 Ethernet PHY Initial Conditions and TX Clock Signal Change

2. Generated pin reconfiguration - Used PinMux tool dev.ti.com/.../
- Generated pin configuration for "AM65xx_SR2.0_beta" and only added PRU_ICSSG0_MII_G_RT and PRU_ICSSG1_MII_G_RT without any other changes
- Attached "AM65xMII.syscfg" and generated "devicetree.dtsi"

3. Changed related devicetree file in SDK (k3-am654-idk.dts)
- Used new pin configuration from PinMux for icssg0_eth and icssg1_eth
- Phy mode reconfigured to "mii"
- Attached final updated file "k3-am654-idk.dts"

4. Recompiled devicetree files

$ export PATH=<PATH_TO_COMPILER>/gcc-arm-9.2-2019.12-x86_64-aarch64-none-linux-gnu/bin/:$PATH
$ export ARCH=arm64
$ export CROSS_COMPILE=aarch64-none-linux-gnu-
$ cd <PATH_TO_SDK>/ti-processor-sdk-linux-rt-am65xx-evm-08_02_00_01/board-support/linux-rt-5.10.100+gitAUTOINC+204ec708dc-g204ec708dc
$ make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- tisdk_am65xx-evm-rt_defconfig
$ make ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- dtbs

5. Create SD card with reconfigured devicetree

Create SD card with default SDK system image
$ <PATH_TO_SDK>/bin/mksdboot.sh --device <SDCARD_DEVICE> --pg 2 --sdk ./

Rewrite devicetree files on SDCARD with changed and recompiled devicetree files
$ cd <PATH_TO_SDK>/ti-processor-sdk-linux-rt-am65xx-evm-08_02_00_01/board-support/linux-rt-5.10.100+gitAUTOINC+204ec708dc-g204ec708dc/arch/arm64/boot/dts/ti/
$ cp k3-am654-*.dtb* <SDCARD_ROOTFS>/boot

After these steps system behaves how is described no Tx on the line

My questions are

1. Is the MII working on IDK board with PRU firmware from SDK?

2. Do I have correct devicetree configuration for MII?

3. What are all necessary steps for switch to MII, miss I something?

attachment.tar.gz

Thank you for your support
Lukas

over 2 years ago

0 Pekka Varis over 2 years ago

TI__Mastermind 27050 points

Lukas Libal1 said:
1. Is the MII working on IDK board with PRU firmware from SDK?

Yes this is noted as tested with 8.2 SDK and ICSSG firmware that comes with SDK. But it is not the primary mode (RGMII is), so testing is more limited and manual compared.

Lukas Libal1 said:
2. Do I have correct devicetree configuration for MII?

3. What are all necessary steps for switch to MII, miss I something?

I'm checking with an engineer that has run MII mode. I can confirm so far EtherCAT has been run with RTOS and EtherCAT firmware on ICSSG using MII mode. So the HW modifications should be accurate.

0 Lukas Libal1 over 2 years ago in reply to Pekka Varis

Intellectual 335 points

Hello Pekka,

Thank you for your response.

So we have confirmed that the HW changes should be sufficient.

Do you have new information regarding MII support by software, firmware in the mentioned Linux SDK?

Regards
Lukas

0 Pekka Varis over 2 years ago in reply to Lukas Libal1

TI__Mastermind 27050 points

Apparently there is a register config change needed. "need to swap the PRU mapping in MII RT TXCFG register. Due to SoC integration issue - RGMII TX and MII TX signals are swapped" . I will look at the TRM and get more details unless you are able to proceed with this.

0 Lukas Libal1 over 2 years ago in reply to Pekka Varis

Intellectual 335 points

Hello Pekka,

you refer to TRM (https://www.ti.com/lit/ug/spruid7e/spruid7e.pdf). The TRM specify for TX data switch bit TX_MUX_SELx in register ICSSG_TXCFGx
see in TRM 6.4.14.12.3 ICSSG_TXCFG0 Register and 6.4.14.12.4 ICSSG_TXCFG1 Register
Update: SR2.0 related parts are 6.5.14.11.3 MII_RT_TXCFG0 Register and 6.5.14.11.4 MII_RT_TXCFG1 Register

This MII related configuration is applied by linux driver, the note is in source also.
see https://git.ti.com/cgit/ti-linux-kernel/ti-linux-kernel/tree/drivers/net/ethernet/ti/icssg_config.c?h=08.02.00.001-rt#n158

We found a related forum thread that ends up with the same behavior we are seeing. The thread ends with offline communication and the thread has no outcome. Participants could provide valuable information. https://e2e.ti.com/support/processors-group/processors/f/processors-forum/939934/am6548-where-to-find-pru-firmware-that-works-with-mii/3600414?tisearch=e2e-sitesearch&keymatch=DP83867IR#3600414

Regards,
Lukas

0 Lukas Libal1 over 2 years ago in reply to Lukas Libal1

Intellectual 335 points

According to information from F. Walzer, not exists tested ICSSG SR2.0 PRU Ethernet firmware with MII and Linux.

My issue with MII is not solved. Proposed usage of MII is not possible. We can lock this thread.

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TMDX654IDKEVM: No Tx traffic with PRU-ICSSG on MII mode