AM2432: Bootloader scratch memory support

Andrea Politano

Part Number: AM2432

Tool/software:

Hi,

I am using AM2432 with the Industrial SDK 11.00.00.08.

I saw that in version 10.01.00 of the SDK the define BOOTLOADER_SCRATCH_MEM_SUPPORT was added in bootloader_soc.h, and in the demo sbl_ospi a new variable gAppimage was added with comment "This buffer needs to be defined for OSPI boot in case of HS device for image decryption and authentication. The size of the buffer should be large enough to accommodate the appimage."
I didn't quite understand in what specific case this memory is needed, why is this needed, and especially how it was possible to boot in previous versions when this memory was not yet used.

My problem is that I am upgrading my custom sbl_ospi project to the new SDK 11 from SDK 9. In this new version if this define is defined, in bootloader.c at the Bootloader_verifyMulticoreImage:728-738 function it says config->args = &gMemBootloaderArgs; while my custom sbl_ospi would expect config->args to remain the ones previously assigned.

What would cause deleting that define?

Could you provide me with extra reference to understand this functionality?

Thank you,

Best regards,

Andrea

3 months ago

0 Vaibhav Kumar 3 months ago

TI__Mastermind 44926 points

Hi,

Allow me sometime to comment on your query.

Regards,

Vaibhav

0 Andrea Politano 3 months ago in reply to Vaibhav Kumar

Prodigy 160 points

Hi Vaibhav,

thank you for your response, are there any updates?

Thank you,

Best regards,

Andrea

0 Vaibhav Kumar 3 months ago

TI__Mastermind 44926 points

Hi Andrea,

Thanks for waiting.

Andrea Politano said:
This buffer needs to be defined for OSPI boot in case of HS device for image decryption and authentication. The size of the buffer should be large enough to accommodate the appimage

I have asked the above from the SW Dev team.

I will respond as soon as I have some feedback on this.

Thanks for your patience again.

Regards,

Vaibhav

0 Vaibhav Kumar 3 months ago in reply to Andrea Politano

TI__Mastermind 44926 points

Hi,

For the buffer introduction in the main.c file for sbl_ospi the following are the comments from the commit id:

Place the encrypted image in the RAM for authentication and decryption
instead of decrypting the image from flash

I will give more detailed explanation to your following questions in sometime:

Andrea Politano said:
I didn't quite understand in what specific case this memory is needed, why is this needed, and especially how it was possible to boot in previous versions when this memory was not yet used.

Respectfully,

Vaibhav

+1 Vaibhav Kumar 3 months ago

TI__Mastermind 44926 points

Update:

Scratch memory was added for supporting booting encrypted image with ospi/emmc boot.
We can't decrypt image in flash memory or emmc memory so we use DDR memory(scratch memory) where we copy the image from flash or emmc memory and decrypt in the DDR memory.

When this implementation did not existed, it used to fail when we used encrypted image for HSSE devices.

Regards,

Vaibhav

0 Andrea Politano 3 months ago in reply to Vaibhav Kumar

Prodigy 160 points

Hi Vaibhav,

thank you for your response.

I have one last doubt, is the encryption only for HSSE variants? Is it mandatory?

Thank you,

Kind Regards,

Andrea

+1 Vaibhav Kumar 3 months ago in reply to Andrea Politano

TI__Mastermind 44926 points

Andrea Politano said:
Is it mandatory?

Yes it is mandatory, it was earlier taken care for GP, HS FS but not for HS SE, hence the fix.

Regards,

Vaibhav

Arm-based microcontrollers

Arm-based microcontrollers forum

AM2432: Bootloader scratch memory support