S32K144 OTA bootloader A-B swap issues

[jackey267]

hi team: 

for S32K144 MCU on FTF-AUT-N1795.pdf 

1 why did you put  two bootloaders at here ？   what did you want to tell?  we were so confused.

2 where is the bootloader should be placed ?  SRAM？Dflash 

3 conflict with AN12323.pdf 

3.1 AN12323.pdf  told us that only one bootloader(16KB) placed at DFLASH at all. 

3.2 how does the memory remapping work of S32K144？ 

thank you for your help .

[jackey267]

hi team： 

for S32K3xx series ：

1.1 how does the memory remapping work? have you released some demo projects about  memory remapping for S32k3xx OTA bootloader as AN12323sw.zip ? 

1.2 what did "Instant switching between firmware" exactly mean? we need more specifics .

2 about S32K3xx firmware update mentioned at  TP-CONNECTS2021-AUT428.pdf  how could you get this done? we need more details .

hope to hear from you soon.thanks.

[lukaszadrapa]

Hi,

there's support in HSE firmware. You can download HSE FW and HSE demo app, HSE OTADEMO from:

https://www.nxp.com/webapp/swlicensing/sso/downloadSoftware.sp?catid=SW32K3-STDSW-D

https://www.nxp.com/webapp/swlicensing/sso/downloadSoftware.sp?catid=SW32K3-REFSW-D

Regards,

Lukas

[jackey267]

hi  Lukas:

there is a project of the automobile body control area . 

1.1 in the past ,we had used S32K144 for our product using the  in place  ways to flash the APP firmware by  UDS CAN bus update .the trouble was the the boot loader itself could not be covered.  

2 but now we are try to use S32K344 to out the S32K144 .

2.1 suppose there are  boot loader_A +APP_A +boot loader_B+APP_B +flash driver(running in SRAM) 5 separate images at all .

2.2 how to arrange the OTA update PLAN  with HSE firmware enabled? Shall we put the boot loader into HSE firmware? 

2.3 requires: 

---the both boot loader_A +APP_A +boot loader_B+APP_B must be covered to update .  

---rolling back .

--- no car downtime during update .

how to make this schema come true  in details ?

thanks .

[lukaszadrapa]

Hi Jack,

FTF-AUT-N1795 seems to be confusing here. But it’s slide for presentation only, there’s no recording or better description of that use case. It’s definitely not about AN12323 – this application note was published about two years later.

Yes, AN12323 has one bootloader only which is placed to Dflash. In case of S32K144 it’s the best solution due to read partitions. Pflash consist of one block only (one read partition). When Pflash is being erased or programmed, the code needs to run from Dflash or from RAM. S32K146 has two Pflash blocks and S32K148 has three Pflash blocks, so this gives us more possibilities (also discussed in AN12323).

S32K144 does not support remapping. There are two options for A/B swap: either compile the code as position independent or track the images and place them to correct flash area.
Notice that S32 Design Studio supports only Position Independent Code (PIC) which can be used for small sections of code. But Position Independent Executable (PIE) is not supported – it’s not possible to create whole project as position independent. AN12323 mentions that IAR compiler can do that.
This has been already solved on S32K3 devices – HW support was added for this.

Regards,
Lukas