Difference between beaglebone-ai64 and beaglebone-ai64-k3r5

Difference between beaglebone-ai64 and beaglebone-ai64-k3r5

[Philip Balister]

I'm looking at the recent update to meta-ti/kirkstone that appears to
add support for the beaglebone ai64 and I am curious why there are two
machines added. I'm going to see if this works ASAP!

Philip

Re: [meta-ti] Difference between beaglebone-ai64 and beaglebone-ai64-k3r5

[Denys Dmytriyenko]

On Sat, Feb 11, 2023 at 01:01:00PM -0500, Philip Balister wrote:
> I'm looking at the recent update to meta-ti/kirkstone that appears to
> add support for the beaglebone ai64 and I am curious why there are two
> machines added. I'm going to see if this works ASAP!

TI K3 family of SoCs utilize a heterogeneous multicore architecture, hence the 
bootflow is quite convoluted... You can read all the details from the official 
docs, also referenced from below links. But, basically, before getting into 
Linux on the main Aarch64 Cortex-A72 cores, it goes through init/boot and 
loads and runs different pieces on 32-bit MCU Cortex-R5F core.

Which means, from OE perspective, you need to be able to build 64-bit Linux 
stack as well as 32-bit bootloader and system firmware. And that means you 
need 2 different toolchains. That is done with OE multiconfig and as a 
byproduct, 2 machine configs. You normally don't use -k3r5 machine config 
directly, as it will be automatically handled by multiconfig dependencies to 
build the necessary MCU bootloader pieces...

You may want to check the first commit that introduced this split:
https://git.yoctoproject.org/meta-ti/commit/?id=f814840465358a6b5429ad20165742ac6e6e6a29

Also, the common k3r5.inc file is rather self-explanatory:
https://git.yoctoproject.org/meta-ti/tree/meta-ti-bsp/conf/machine/include/k3r5.inc
https://patchwork.yoctoproject.org/project/ti/patch/20230211234205.3042518-1-denis@denix.org/

-- 
Denys

Re: [meta-ti] Difference between beaglebone-ai64 and beaglebone-ai64-k3r5

[Philip Balister]

Thanks Denys, this is extremely helpful!

Philip

On 2/11/23 19:24, Denys Dmytriyenko wrote:
> On Sat, Feb 11, 2023 at 01:01:00PM -0500, Philip Balister wrote:
>> I'm looking at the recent update to meta-ti/kirkstone that appears to
>> add support for the beaglebone ai64 and I am curious why there are two
>> machines added. I'm going to see if this works ASAP!
> 
> TI K3 family of SoCs utilize a heterogeneous multicore architecture, hence the
> bootflow is quite convoluted... You can read all the details from the official
> docs, also referenced from below links. But, basically, before getting into
> Linux on the main Aarch64 Cortex-A72 cores, it goes through init/boot and
> loads and runs different pieces on 32-bit MCU Cortex-R5F core.
> 
> Which means, from OE perspective, you need to be able to build 64-bit Linux
> stack as well as 32-bit bootloader and system firmware. And that means you
> need 2 different toolchains. That is done with OE multiconfig and as a
> byproduct, 2 machine configs. You normally don't use -k3r5 machine config
> directly, as it will be automatically handled by multiconfig dependencies to
> build the necessary MCU bootloader pieces...
> 
> You may want to check the first commit that introduced this split:
> https://git.yoctoproject.org/meta-ti/commit/?id=f814840465358a6b5429ad20165742ac6e6e6a29
> 
> Also, the common k3r5.inc file is rather self-explanatory:
> https://git.yoctoproject.org/meta-ti/tree/meta-ti-bsp/conf/machine/include/k3r5.inc
> https://patchwork.yoctoproject.org/project/ti/patch/20230211234205.3042518-1-denis@denix.org/
>