Add support for MIMXRT1042XJM5B

[MulattoKid]

This PR adds support for MIMXRT1042XJM5B. I've tested this locally on the EVK and a custom PCB, and it works on both.

My approach was:

• search for places where the 1052 was referenced and adding support for the 1042
• run make and fix compilation warnings for both wolfBoot and the test application

I added local support for patching the test app's ELF file to add the signature to it. Doing so I could flash both wolfBoot and the test app through VSCode, and was able to get to both binaries main entrypoints.

I've not tested that this doesn't break any of the other RT targets.

@danielinux This is the support we discussed during our call. Hopefully this can help getting 1042 support included in wolfBoot.

Kind regards,
Daniel

[dgarske]

See ZD 17479

[MulattoKid]

One thing I forgot to mention was that in uart_init in hal/imx_rt.c I had to specifically configure the pins used for debug output like so:

CLOCK_EnableClock(kCLOCK_Iomuxc);
IOMUXC_SetPinMux(IOMUXC_GPIO_AD_B0_12_LPUART1_TX, 0U);
IOMUXC_SetPinMux(IOMUXC_GPIO_AD_B0_13_LPUART1_RX, 0U);
IOMUXC_SetPinConfig(IOMUXC_GPIO_AD_B0_12_LPUART1_TX, 0x10B0U);
IOMUXC_SetPinConfig(IOMUXC_GPIO_AD_B0_13_LPUART1_RX, 0x10B0U);

When not doing this, I didn't get any debug output from the bootloader. I did compile with

DEBUG_UART?=1
PRINTF_ENABLED?=1

in my .config. Not sure if I'm missing something?

[dgarske]

Hi @MulattoKid ,

Thank you so much for this PR. Your contributor agreement has been accepted and placed on file.

We've assigned this PR to @bigbrett for review.

Thanks,
David Garske, wolfSSL

[bigbrett]

Code additions look great, and confirmed no regressions on this branch when building for the RT1052 and RT1054 targets. Note that, since I don't have hardware, I'm unable to test this on the RT 1042.

[bigbrett]

One thing I forgot to mention was that in uart_init in hal/imx_rt.c I had to specifically configure the pins used for debug output like so:

CLOCK_EnableClock(kCLOCK_Iomuxc);
IOMUXC_SetPinMux(IOMUXC_GPIO_AD_B0_12_LPUART1_TX, 0U);
IOMUXC_SetPinMux(IOMUXC_GPIO_AD_B0_13_LPUART1_RX, 0U);
IOMUXC_SetPinConfig(IOMUXC_GPIO_AD_B0_12_LPUART1_TX, 0x10B0U);
IOMUXC_SetPinConfig(IOMUXC_GPIO_AD_B0_13_LPUART1_RX, 0x10B0U);

When not doing this, I didn't get any debug output from the bootloader. I did compile with

DEBUG_UART?=1
PRINTF_ENABLED?=1

in my .config. Not sure if I'm missing something?

@MulattoKid Not sure off the top of my head, I will look into this more. It doesn't appear that the hal layer does this pin mux initialization, which could be why printouts don't show up. Regardless, I don't want this to block your PR.

[dgarske]

Thank you @MulattoKid

[MulattoKid]

Thanks for the quick responses :)