LIN Slave Mode Support on TJA1124 with S32G3 VNP-RDB3 Board

[A_VIJAYA7]

Hi NXP Support Team,

We are currently evaluating LIN communication on the S32G3 VNP-RDB3 board, utilizing the LLCE LIN channels connected to the onboard TJA1124 LIN transceiver. Based on available information, the TJA1124 appears to be configured as a commander-channel device by default.

To meet our application requirements, we intend to configure all four LLCE LIN channels as LIN slaves. We would like to confirm whether the TJA1124 transceiver supports slave-mode operation when the LIN controller is configured accordingly.

To verify whether the TJA1124 transceiver is capable of operating in slave mode when interfaced with LLCE LIN channels that are configured as LIN slaves?

Please let us know whether the TJA1124 supports this configuration, or if additional components or firmware adjustments are required.

Thank You.

[alejandro_e]

Hello @A_VIJAYA7,

Thanks for contacting us again. Checking the TJA1124 documentation, you can see that it only supports Master mode. If required you could connect directly to the FLEX_LIN2 lines comming from the S32G2, you can solder a connector in J188 space (which is not populated) and connect an external board to it:

You can also remove R1059 and R1060 to only use the signal for the external board.

The connector is located here:

Please note that we do not offer any example to use LIN as a slave, so I strgonly recommend checking section Chapter 49 LINFlexD of the reference manual [page 2453, S32G3 Reference Manual, Rev. 4, 02/2024]

Let me know if you need more support

[suryashankar]

Hi @alejandro_e ,

The Capgemini India SW team asks:

• TJA1124 can only be configured as LIN Master (commander) and the same is applicable for SJA1124 also. Please confirm.
• Additionally, From the attached document("ah504215-SJA1124 _ TJA1124 Application Hints(1.5)") section 3.3 & the datasheet of SJA1124, we assumed (implicit) that by configuring the MCFG register to 0x00 (Address 0xF0h), the SJA1124 shall act as LIN slave. Please share your feedback.

Kindly review and confirm.

Thanks and Regards,

Suryashankar Dasgupta

[alejandro_e]

Hello @suryashankar and @A_VIJAYA7,

I have reviewed the document, what I understand from is that the R_commander and R_receiver can be enabled and disabled with the MCFG, which are used for signal integrity in the LIN protocol, this does not change the rol of the controller . Please note that my area of expertise is the S32G, not the transceivers of this topic, the conclusions I have shared are from reading the datasheets of the components, to get support from the experts on those components please post a question in Other-NXP-Products, there one of my colleagues with more expertise in those areas will be able to help you.

Let me know if you have more questions

[suryashankar]

Hi @alejandro_e ,

The customer has purchased S32G3 reference board and working on configuring LLCE LIN as slave with TJA1124 for A53 core Linux environment.

But NXP clarified that, TJA1124 cannot be configured as LIN Slave and suggested to use TJA1024 which can be configured either Master or Slave.

Note: They are not going to use LINFlexD outside LLCE.

Please share your inputs to take the decision & proceed further.

• As aligned, LLCE-LINFlexD support only UART mode. And to configure as LIN master/slave, the customer would expect driver support from NXP as similar to LLCE-CAN. Why is that not provided by NXP? They also understand from RTD driver that it is directly accessing the LINFlexD registers which is outside of LLCE. They assume, NXP to provide driver for LLCE-LINFlexD. Please feedback.
• If NXP is not providing the driver for LLCE-LINFlexD, Please share the details of dedicated support from NXP. Timeline and cost to develop & integrate LLCE-LINFlexD driver to configure LLCE LIN as slave?

Kindly review and share your feedback!

Thanks and Regards,

Suryashankar Dasgupta

[alejandro_e]

Hello @suryashankar and @A_VIJAYA7,

Just to clarify, using LLCE or not using it, does not affect the master/slave capabilities of the PHY chips, LLCE is an S32G internal communication accelerator, it only offloads processing from the main cores (A53 or M7).

Regarding the LLCE-LinFlexD drivers, the design of the BSP is handle internally I cannot give you any details on why it is done a certain way since I don't have them. Regading the RTD LLCE examples, they do not come with the standard RTD package, you will need to enter FlexNet and follow this path: Automotive SW – S32G Standard Software > Automotive SW - S32G - LLCE Driver + Firmware, then select the version best suited for your project:

Please avoid using version 1.0.10 as some unrecoverable issues have been found. I would recommend version 1.0.9.

Once installing those packages in S32DS or EB Tresos, you will see examples for LLCE.

Regarding the cost and time for new features added to the BSP, I am not able to help with that, I can only guide you in technical topics. You could reach out to your NXP Sales Representative for more details regarding this, you can also check these links:

NXP Engineering Services | NXP Semiconductors

Professional Support for Processors and Microcontrollers | NXP Semiconductors

Professional Engineering Services Information Request (CAM802 2019) | NXP Semiconductors

Please let me know if this information solved all your questions

[A_VIJAYA7]

Dear NXP Team,

Thank you for your continued support.

We are currently working on the S32G3 platform using the A53 core running Linux, with BSP version 43. We are not using the M7 core or RTD drivers. The existing Linux driver supports LINFlexD in UART mode.

We kindly request your support with the following queries:

Could you please provide a Linux driver for LINFlexD that supports LIN mode
How is LIN functionality validated on the A53 core with Linux, please share documentation and test procedures to validate LIN on a53 core.
In the existing llce_mailbox.c driver, the LLCE firmware appears to be disabled and is currently functioning in UART mode. Could you please provide enable LLCE firmware for LIN functionality


Thanks & Regards,
Vijaya

[alejandro_e]

Hello @A_VIJAYA7,

As mentioned before we do not offer any example nor guide to use LIN mode in Linux, if you require that feature from us you can create a request in the links I shared in my previous reply.

If you decide to develop it yourself you can use the following file bsp43.0-6.6.52-rt/drivers/tty/serial/fsl_linflexuart.c and the RTD example I mentioned before, once you download the installer (S32G_LLCE_GATEWAY_1_0_9_D2408.exe), you will find the FW in C:\NXP\S32G_LLCE_1_0_9\firmware\llce_bin\s32g3\bin, you can find it in ELF, binary and array format. You can also check the bsp43.0-6.6.52-rt/drivers/mfd/llce-core.c file to get familiarized with the flow of how to load the firmware from a Linux device.

I apologize for not being able to cover your requirements, however I can help you in case you find specific problems during your integration or if you have problems contacting professional services to request this feature.

Please let me know if you have more questions

[A_VIJAYA7]

Hi NXP Team,

We are currently working with the LLCE firmware as per the attached LLCE Firmware User Guide, specifically referring to Module 1.5 – LLCE LIN Firmware.

For LIN communication, we are invoking firmware commands via the llce-mail.c driver. However, we are encountering the following issue:

Error: LLCE_LIN_TX_HEADER_ERROR
Description: Unable to transmit LIN frame.

Could you please guide us on how to resolve this issue? Additionally, if you have any validated reference documents or examples related to this module and driver integration, kindly share them.

Best regards,
Vijaya

[alejandro_e]

Hello @A_VIJAYA7,

For what I can see in the code (llce_interface_lin.h#L161), the possible erros are:

/**
* Erroneous header transmission such as:
* - Mismatch between sent and read back data
* - Identifier parity error
* - Physical bus error.
*/

If you need a deeper analysis please create a new post or create a private support ticket, preferable add all the needed details, for example the messages interchanged up to the point of the error or if it is the first message you are trying yo sent to the LLCE subsyste.

Thanks