Hi Antonio,

This might be a good roadmap addition, especially for the systems with large memory, where the benefit of the smaller image size significantly outweighs the additional bootloader size.

Kind Regards,

Tomasz

From: Antonio De Angelis <Antonio.DeAngelis@arm.com>
Sent: Friday, January 19, 2024 6:57 PM
To: tf-m@lists.trustedfirmware.org; Tomasz Jastrzębski <tdjastrzebski@wp.pl>
Subject: Re: [TF-M] Pre-encryption image compression (re-posting as a new topic)

Hi Tomasz,

currently TF-M does not implement support of any kind of compressed image update or delta firmware upgrades.

/Antonio

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From: Tomasz Jastrzębski via TF-M <tf-m@lists.trustedfirmware.org>
Sent: Friday, January 19, 2024 14:05
To: tf-m@lists.trustedfirmware.org <tf-m@lists.trustedfirmware.org>
Subject: [TF-M] Pre-encryption image compression (re-posting as a new topic)

Hello All,

Does the current TF-M version support image compression before image is encrypted?

Needless to say, compression after the image has been encrypted would not yield reasonable compression ratio.

I am showing that *.bin files, even built with MinSizeRel option, zip-compress with minimum 50% compression ratio so probably this would make sense. Tested with STM32U5 target and GCC.

“PSA Certified Firmware Update API” document in sections 3.1 and 3.2 provides for image compression.

Kind regards,

Tomasz Jastrzębski