AM62P: Bringing up Android & FreeRTOS in OSPI boot mode

Hi Abhishek,

Is this continuation of below thread or new topic?
SK-AM62-LP: MCU+ SDK Loading android and FreeRTOS from EMMC


The standard Android binaries and the partitions it go in to is mentioned here
https://software-dl.ti.com/processor-sdk-android/esd/AM62PX/10_01_01/docs/devices/AM62PX/android/Application_Notes_Partitions.html

Which binaries from the standard Android boot process you want to not use and replace with something else?


Regards,
Vishal

Hi Vishal,

Vishal Mahaveer said:

Is this continuation of below thread or new topic?
SK-AM62-LP: MCU+ SDK Loading android and FreeRTOS from EMMC

Actually no, I think in this thread they are trying to do it using eMMC, but i am planning to do it with SD card. Based on what i read, i think the idea is kind of same.

Vishal Mahaveer said:

The standard Android binaries and the partitions it go in to is mentioned here
https://software-dl.ti.com/processor-sdk-android/esd/AM62PX/10_01_01/docs/devices/AM62PX/android/Application_Notes_Partitions.html

Which binaries from the standard Android boot process you want to not use and replace with something else?

Since I’m still new to this, I may be missing some parts of the overall flow. My goal is to enable communication from an Android app running on the A53 core to FreeRTOS running on the R5 core. The Android-side development is complete — the app, HAL layer, SE policy configurations, and port setup are all in place.

On the R5 side, I’m using the ipc_rpmsg_echo_linux_am62px-sk_mcu-r5fss0-0_freertos_ti-arm-clang example application to log messages received via IPC. I’ve flashed this example using the default_sbl_ospi_linux_hs_fs.cfg configuration.

I’ve attempted the following boot methods:

1. OSPI Boot Mode (via boot mode pin configuration):
   The R5 core boots and I can see the expected logs. However, Android does not boot in this setup.

2. SD Card Boot Mode (via boot mode pin configuration):
   Android boots successfully in this mode, but the R5 core does not show the custom logs from the example application I flashed. It seems to be running a different image or configuration, which I’m not sure about.

From this, it looks like Android and the R5 firmware are not aligning properly depending on the boot method. I would appreciate any suggestions on the correct or recommended way to boot both Android and FreeRTOS together. Also, if there is a better boot mode for this use case aside from OSPI, I’m open to trying that as well.

Thanks & Regards,
Abhishek

Hi Abhishek,

Which R5 core are you referring to here? MCU R5 or DM R5?

Regards,
Vishal

Hello Vishal,
I am referring to MCU R5.

Regards,
Abhishek

Hi Abhishek,

In that case, only the MCU R5 firmware needs to be placed in the filesystem and the Linux Kernel remoteproc driver should take care of bringing up the MCU R5 core and load the firmware to MCU R5.

It is already done in default SDK
https://git.ti.com/gitweb?p=android/vendor-ti-am62x.git;a=blob;f=firmware/Android.bp;h=f52af8a4eeb52f1d6414c1f43c8af6d920814dda;hb=refs/heads/d-android15-release#l9

The IPC should be working as is.

If you made additional changes to the IPC example and want your custom MCU R5 firmware to be used, replace the file in Android File System source and rebuild Android images.


Regards,
Vishal

Hello Vishal,

Thank you for the clarification. I’ve also gone through the link you shared. From what I understand, I need to place my custom IPC example in the vendor/firmware/ti-ipc directory and rebuild Android to get it working—please correct me if I’m wrong.

I have a few doubts that I hope you can help clarify:

1. After compilation, we typically get .appimage, .appimage.hs_fs, and .out files. Which of these should be placed in the directory mentioned above (vendor/firmware/ti-ipc)?

2. Once the board is booted, how can I view the R5 core logs?

   • Can I use Minicom on /dev/ttyUSB3 (which is where I usually receive R5 logs)?

   • Or is there any Android-side command (e.g., using grep or logcat) to filter logs related to the R5 core?
     
     

Regards, 
Abhishek 

Hi Abhishek,

It should be same as what is used in Linux SDK (Android also uses Linux Kernel).

1. ".out" file
2. remote core logs are not part of logcat. It should come in ttyUSB3.

Regards,
Vishal