Added Cortex-M52 (Armv8.1-M) port

[cpussw01]

Fix #518
Add ThreadX port for Cortex-M52, supporting three toolchains:

• GNU (GCC)
• AC6 (Arm Compiler 6)
• IAR

Cortex-M52 is an Armv8.1-M Mainline processor sharing the same architecture profile as Cortex-M55 and Cortex-M85. The port is functionally identical to the existing Cortex-M85 port.

PR checklist

• Updated function header with a short description and version number
• Added test case for bug fix or new feature
• Validated on real hardware

[fdesbiens]

Hi @cpussw01.

Thank you for this contribution! Before we can accept it, you need to sign the Eclipse Contributor Agreement (ECA). The purpose of the ECA is to provide a written record that you have agreed to provide your code and documentation contributions under the licenses used by the Eclipse ThreadX project. It also makes it clear that you are promising that what you are contributing to Eclipse is code you wrote, and you have the necessary rights to contribute it to our projects. And finally, it documents a commitment from you that your open source contributions will be permanently on the public record.

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Be sure to use the same email address when you register for the account that you intend to use on Git commit records. Also, please add your GitHub ID to your Eclipse account. This enables synchronisation between Eclipse-owned infrastructure and GitHub.

Here is the link to sign the ECA:
https://accounts.eclipse.org/user/login?destination=user/eca

[cpussw01]

Hi @cpussw01.

Thank you for this contribution! Before we can accept it, you need to sign the Eclipse Contributor Agreement (ECA). The purpose of the ECA is to provide a written record that you have agreed to provide your code and documentation contributions under the licenses used by the Eclipse ThreadX project. It also makes it clear that you are promising that what you are contributing to Eclipse is code you wrote, and you have the necessary rights to contribute it to our projects. And finally, it documents a commitment from you that your open source contributions will be permanently on the public record.

Signing the ECA requires an Eclipse Foundation account if you do not already have one. You can create one for free at https://accounts.eclipse.org.

Be sure to use the same email address when you register for the account that you intend to use on Git commit records. Also, please add your GitHub ID to your Eclipse account. This enables synchronisation between Eclipse-owned infrastructure and GitHub.

Here is the link to sign the ECA: https://accounts.eclipse.org/user/login?destination=user/eca

Hi @fdesbiens
I have signed the ECA , and my github account @cpussw01 has been linked to this ECA account.
Now, this code contribution work can go on forward.
Thank you.

[fdesbiens]

Hi @cpussw01. Thank you. The ECA check now passes.

I will ask a team member to review.

[rahmanih]

Hi @cpussw01
welcome to the eclipse threadx world 🎉🎉.

Cortex-M52 is an Armv8.1-M Mainline processor sharing the same architecture profile as Cortex-M55 and Cortex-M85. The port is functionally identical to the existing Cortex-M85 port.

indeed, the Cortex-M52 is identical to the Cortex-M85.

would it possible for you to update the script below by adding cortex_m52 then run it to copy the ARMv8.1-M files in the destination folders.

threadx/scripts/copy_armv8_m.sh

Line 10 in 3726d79

target_mcu="cortex_m33 cortex_m55 cortex_m85"

PS: I'm assuming you have tested the commit on a real hardware.

regards
haithem.

[JidongMei]

Hi @cpussw01 welcome to the eclipse threadx world 🎉🎉.

Cortex-M52 is an Armv8.1-M Mainline processor sharing the same architecture profile as Cortex-M55 and Cortex-M85. The port is functionally identical to the existing Cortex-M85 port.

indeed, the Cortex-M52 is identical to the Cortex-M85.

would it possible for you to update the script below by adding cortex_m52 then run it to copy the ARMv8.1-M files in the destination folders.

threadx/scripts/copy_armv8_m.sh

Line 10 in 3726d79

target_mcu="cortex_m33 cortex_m55 cortex_m85"

PS: I'm assuming you have tested the commit on a real hardware.

regards haithem.

Hi haithem
I have updated copy_armv8_m.sh, and using it to update the cortex_m52 port content.
Sure, the cortex_m52 port has been tested on a real Cortex-M52 hardware.
B,R

[cpussw01]

Hi @fdesbiens

Since it comes to the end of 2026.06, which might be the end of 2026-02 KM.
Is there anythings that blokcs this PR? or anythings i can do for help.

Thank you.

[fdesbiens]

Thank you for this, and for doing it the right way round.

The thing I most wanted to check was whether the 63 port files were hand-copied. They are not: the substantive change is one word in scripts/copy_armv8_m.sh, and checking out the branch and re-running the generator produced no diff at all. That means Cortex-M52 will pick up every future Armv8-M fix without anyone porting it by hand, which is the property Cortex-A34 and Cortex-A78 lacked until recently. I also confirmed the output is identical to the Cortex-M85 port modulo the core name, across all three toolchains.

I have retargeted this from master to dev and pushed three things to your branch.

Rebased onto dev, then regenerated. This turned out to matter more than a formality. ports_arch/ARMv8-M has moved since you branched, so regenerating changed twelve files — the port as committed was generated from the older shared source. Among what it picks up: MOV r0, 0 becomes MOV r0, #0 in the schedule and system-return paths, which is the non-canonical immediate form GNU as tolerates and LLVM's assembler rejects; and gnu/src/tx_initialize_low_level.S disappears, because the shared source no longer has it. Nothing for you to do — it is exactly the benefit of generating the port.

Added cmake/cortex_m52.cmake. Every other Cortex-M core has one on dev, and without it the port cannot be selected the documented way. It could not have been in your original change, since those files did not exist on master.

Added a PORT_TARGET entry to scripts/check_clang.sh, so the port is covered by the LLVM assembly check.

Two details worth recording, because both look like a broken port if you meet them cold.

The float ABI is load bearing. -mcpu=cortex-m52 implies Helium, and building soft-float fails on every file with multilib configuration error: No library available for MVE with soft-float ABI. Cortex-M55 and Cortex-M85 already carry -mfloat-abi=hard for the same reason, and the new files do too.

The compiler has to know the core. arm-none-eabi-gcc only learned -mcpu=cortex-m52 in GCC 14; 13.x rejects it outright, and 13.x is what several distributions still ship. The toolchain file therefore pins the project's reference toolchain the way cmake/cortex_r52.cmake does, with an ARM_TOOLCHAIN_PATH override and a guard that falls back to PATH when the pinned directory is absent.

Verified after the changes: scripts/copy_armv8_m.sh is a no-op, so the tree matches its source; scripts/check_ports.sh passes; scripts/check_clang.sh passes with the new core included, 724 of 724 assembly sources and nothing skipped; and the port builds through CMake with Arm GNU Toolchain 14.3.Rel1, producing a 281 KB libthreadx.a. It also compiles cleanly with Arm Toolchain for Embedded 22.1.0.

Still unchecked on the PR is hardware validation. For a port generated from a validated shared source that carries less weight than it would for hand-written assembly, but it is worth saying plainly that nobody has run this on silicon.