topic Re: i.MX RT1170 Custom Bootloader in i.MX Processors

i.MX RT1170 Custom Bootloader

joséviníciusmel — Mon, 15 May 2023 23:26:48 GMT

Hi guys,

I will develop a custom bootloader in my custom i.MX RT1170 board. In my case, a flash driver will be read through the USB to update the primary application.

I am studying the "evkmimxrt1170_mcuboot_opensource" and the "ota" examples and I have some doubts and I would appreciate some help.

1) Application jump: I tried to study the "evkmimxrt1170_mcuboot_opensource" example but I don't have the i.MX RT1170 evaluation board to debug. I think that the steps to jump are the following:

// Cleanup:

SCB_DisableICache();
SCB_DisableDCache();
ARM_MPU_Disable();

// Peripherals disable (example, USB):

// ...

// Jump:

__set_CONTROL(0);
__set_MSP(vt->msp);
__ISB();
((void (*)(void))vt->reset)();

Is there more steps to pay attention before the jump?

2) Related with the primary application, in my previous bootloaders I had to set the interrupt vector table again after the jump. How is this done on i.MX RT processors?

Thanks.

Re: i.MX RT1170 Custom Bootloader

jingpan — Wed, 17 May 2023 05:31:32 GMT

Hi @joséviníciusmel ,

Yes, if your application doesn't change vector table address, you must add it here. It's the IOMUXC_GPR26 register.

Regards,

Jing

Re: i.MX RT1170 Custom Bootloader

joséviníciusmel — Thu, 18 May 2023 00:37:39 GMT

Hi,

First, thanks for your reply.

Where is this done in the ota examples (like, evkmimxrt1170_lwip_httpssrv_ota_wifi)?

I tried to find the IOMUXC_LPSR_GPR_GPR26_CM7_INIT_VTOR, but I couldn't see this macro being called.

And related with the jump process, do you think that these commands are ok?

Thanks.

Regards,

Vinícius.

Re: i.MX RT1170 Custom Bootloader

jingpan — Thu, 18 May 2023 07:27:24 GMT

Hi @joséviníciusmel ,

If vector table is changed, VTOR must be reconfigured, either in bootloader or in application.

You jump process is fine.

Regards,

Jing

Re: i.MX RT1170 Custom Bootloader

joséviníciusmel — Thu, 18 May 2023 23:04:44 GMT

Hi Jing,

Thanks!