Porting to Tiva C Series TM4C123G LaunchPad

[tdwebste]

As a learning exercise I am considering porting Chibios/RT to Tiva C Series TM4C123G LaunchPad

Is this Porting the OS to another MCU using the same core.
stm32f4x The Cortex-M4 core features a Floating point unit (FPU)
and
TM4C123x Cortex M4F

Or is this Porting the OS to a whole new architecture?

I will be doing this in my spare time.
Just want to know what I am getting into.

[Marco]

Hello tdwebste,

The Tiva C Series TM4C123G Launchpad is indeed using the same core.

I'm also porting ChibiOS/RT to this new platform. The ChibiOS/RT 2.6 kernel is already working. The Pal, Serial and I2C driver are already implemented but not ready for release yet.
At the moment i'm trying to get ChibiOS/RT 3.0 running.

Maybe we can work together to get this done?

Marco

[Giovanni]

The Kernel port is exactly the same, you just need to add few files specific for your micro (vectors table). You can use the kernel alone without HAL on any Cortex-M device.

The HAL port has to be written from scratch and that is the heaviest part, device drivers take time.

Edit: I posted just after Marco, a joint effort would be great.

Giovanni

[tdwebste]

Marco

Can you please share the github address of your fork?
Also I think we should move this discussion to Contributions

[Marco]

At the moment there is no git(hub) or svn repository for the Tiva C Series port. All files are local on my pc.

I was figuring out what would be the best way to publish this port.
A github repository with only the Tiva-related files following the ChibiOS directory structure would be ideal in my opinion.
Users who want to use the Tiva HAL could then add the repository to their existing ChibiOS directory.

I'm not really sure if this is possible. If someone knows if this is possible or not please tell me. I'll setup a github repository as soon as possible.

Marco

[Giovanni]

A good approach would be to structure your files in such a way that you can just copy them over the chibios structure.

Note that the structure has changed quite a bit in 3.0, you may decide to target your efforts to that version.

Giovanni

[Marco]

Sounds like a good idea.

I'm aware of the new file structure in 3.0 and was not planning to support and develop for version 2.6.2.

What about the ChibiOS license present in each file in the repository. Does this port needs to add the same licence aswel as this is not an official port (yet )?

Marco

[Giovanni]

It is your work, you don't need any copyright attribution unless it is going to be integrated in the official distribution. You may also use any license you like as far it is compatible with GPL3 (GPL3 itself, apache 2.0, BSD 3-clauses, etc).

Giovanni

[tdwebste]

A github repository with only the Tiva-related files following the ChibiOS directory structure would be ideal in my opinion.

In that case we want to fork and follow chibios 3.0 with git and this subtree is effectively a branch rebased onto of the chibios master.

The files we touch in the git fork are exactly that only the Tiva-related files following the ChibiOS directory structure. And when things change upstream in chibios 3.0 master we pull them commit by commit when things break.

When users want to use the Tiva HAL they will pull from us.

If we want to use different licensing which I actually do not see a need for.
I am fine with using Apache 2.0, but if you prefer another let me know. Is gpl v2 acceptable?
Marco, Who should we assign the copyright to. Or retain it for ourselves?

Than we would create a git submodule and NEVER touch code in the chibios 3.0 tree.
The git submodule will work well if all the Tiva HAL files fall in to a directory which can be copied into the chibios structure.

Marco,
This is weekend work for me. If you can share your current work via a simple github upload. I can do the git structuring work.

[tronicgr]

I just seen this new Tiva C Series TM4C1294 ... Lots of features for just $19 ...!


http://www.ti.com/tool/ek-tm4c1294xl


Thanks
Thanos