On Wed, 21 Apr 2021 at 18:56, Glaropoulos, Ioannis via TF-M < tf-m@lists.trustedfirmware.org> wrote:
I would like to ask the community whether these issues have been raised in the past – and if so, please, inform me what the conclusions have been. Are there current activities that attempt to address the problems raised above? Not been able to fully utilize the FP context stacking in Non-Secure Zephyr applications that integrate with TF-M removes value of our TF-M based solutions.
Thanks! I am looking forward to hearing the thoughts of the community.
Hi Ioannis,
The previous technical forum call did discuss FP usage ... I don't think you were on the call at the time, but the presentation and video can be viewed here, and should point to the people to follow up with here on the mailing list of on phabricator, etc.
Presentation: https://www.trustedfirmware.org/docs/FP-support-in-TF-M.pdf
Video link(s) available here: https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
Best rehards, Kevin
Hi Kevin, Thanks for the link to the presentation 😊
I guess, then, Feder Liang, as the author of the presentation, should be able to provide some feedback on the questions I raised?
Once more, I am stressing that our questions concern the usage of FPU in Non-Secure applications that integrate with TF-M today; it is not about future improvements for FPU support inside TF-M, which was (I guess) the main point of this presentation.
Best, Ioannis
From: Kevin Townsend kevin.townsend@linaro.org Sent: Wednesday, April 21, 2021 8:03 PM To: Glaropoulos, Ioannis Ioannis.Glaropoulos@nordicsemi.no Cc: tf-m@lists.trustedfirmware.org Subject: Re: [TF-M] Supporting integrated Non-Secure RTOS applications that use the FPU
On Wed, 21 Apr 2021 at 18:56, Glaropoulos, Ioannis via TF-M <tf-m@lists.trustedfirmware.orgmailto:tf-m@lists.trustedfirmware.org> wrote: I would like to ask the community whether these issues have been raised in the past – and if so, please, inform me what the conclusions have been. Are there current activities that attempt to address the problems raised above? Not been able to fully utilize the FP context stacking in Non-Secure Zephyr applications that integrate with TF-M removes value of our TF-M based solutions.
Thanks! I am looking forward to hearing the thoughts of the community.
Hi Ioannis,
The previous technical forum call did discuss FP usage ... I don't think you were on the call at the time, but the presentation and video can be viewed here, and should point to the people to follow up with here on the mailing list of on phabricator, etc.
Presentation: https://www.trustedfirmware.org/docs/FP-support-in-TF-M.pdfhttps://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.trustedfirmware.org%2Fdocs%2FFP-support-in-TF-M.pdf&data=04%7C01%7CIoannis.Glaropoulos%40nordicsemi.no%7C81e9cabd5935427db16408d904efc744%7C28e5afa2bf6f419a8cf6b31c6e9e5e8d%7C0%7C0%7C637546250559599334%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=sT2OXyRh93HIyqmoc1dcvYhB%2Bzvs0hAnnkKb1ZeDEeY%3D&reserved=0
Video link(s) available here: https://www.trustedfirmware.org/meetings/tf-m-technical-forum/https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.trustedfirmware.org%2Fmeetings%2Ftf-m-technical-forum%2F&data=04%7C01%7CIoannis.Glaropoulos%40nordicsemi.no%7C81e9cabd5935427db16408d904efc744%7C28e5afa2bf6f419a8cf6b31c6e9e5e8d%7C0%7C0%7C637546250559609325%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=RgWDNXjPgTzgzT3rMvx7EUPMDUakFdTk1Tq4uTk2ZYw%3D&reserved=0
Best rehards, Kevin
On Thu, 22 Apr 2021 at 09:23, Glaropoulos, Ioannis < Ioannis.Glaropoulos@nordicsemi.no> wrote:
Once more, I am stressing that our questions concern the usage of FPU in Non-Secure applications that integrate with TF-M today; it is not about future improvements for FPU support inside TF-M, which was (I guess) the main point of this presentation.
Looking at this a bit further it is indeed a serious issue, since most modern applications are going to want to make use of the FPU. This prevents the FPU from being used inside NS interrupts as well.
I’m not sure if there are currently any change requests that identify or fix this problem (I’ll look), but it’s something that should have some sort of test on the NS side, for sure.
Do you mind filing the details on TF-M’s phabricator and it can more easily be tracked there?
Thanks for bringing this up, Kevin
tf-m@lists.trustedfirmware.org
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Glaropoulos, Ioannis -
Kevin Townsend