i.MX RT1052 + MPU + FreeRTOS v10 hard fault

[cup-a-coffee]

I was trying out the Memory Protection Unit (MPU) feature for RT1052 and found it hard faulting with FreeRTOS. We have an in-house, functional MPU + FreeRTOS v10.2.1 solution for Microchip SAME70, so porting to RT1052 was easy.

Some information about the crash:

• Code runs in XIP on the stock NOR flash on the dev board
• Code crashing upon creating a privileged FreeRTOS task with statically allocated task stack (from DTCM)
• Code doesn’t crash when the MPU is not used

Fault registers (SCB) dump:
SCB->HFSR  = 0x40000000 (Hard fault)
SCB->CFSR  = 0x01000000 (Configurable fault) -> Usage fault: Illegal unaligned load or store
SCB->DFSR  = 0x00000000 (Debug fault)
SCB->AFSR  = 0x00000000 (Auxiliary fault)
SCB->BFAR  = 0x00000000 (Bus fault address)
SCB->MMFAR = 0x00000000 (MemManage fault address)
SCB->ABFSR = 0x00000000 (Auxiliary bus fault)

Questions

1. Is there an example project with RT105X + MPU + FreeRTOS v10 support? The closest I saw is a BOARD_ConfigMPU() generated from the MCUXpresso project.
2. Do you have any suggestions regarding the crash?

[cup-a-coffee]

I reviewed all the NXP MPU demo code, but I don't see any that uses a privileged task.

Is there a sample project in the SDK the uses a privileged task in FreeRTOS?

[jeremyzhou]

Hi @cup-a-coffee ,
Sorry for replying late.
As I mentioned before, the SDK library doesn't provide the MPU-enable FreeRTOS demos, and the developers need to port FreeRTOS-MPU demos to RT1052 by themselves.
Have a great day,
TIC

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[jeremyzhou]

Hi @cup-a-coffee ,
Thank you for your interest in NXP Semiconductor products and for the opportunity to serve you.
1）Is there an example project with RT105X + MPU + FreeRTOS v10 support?
-- Regarding the FreeRTOS, the MPU feature is optional, in the SDK library, it doesn't provide the MPU-enable FreeRTOS demos.
2) Do you have any suggestions regarding the crash?
-- According to the information you provided, I'd like to suggest you refer to FreeRTOS-MPU demos in the library first.
Have a great day,
TIC

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- We are following threads for 7 weeks after the last post, later replies are ignored
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