RTOS/TI-RTOS: Bootloader and app

The details of boot loading application on AM335x evaluation platforms is provided here:

http://processors.wiki.ti.com/index.php/Processor_SDK_RTOS_BOOT_AM335x/AM437x

The bootloader binary and application binary are separate and need to be flashed in different offset in the SPI flash. the bootloader binary is flashed at 0x000000 and profinet application needs to be flashed at 0x20000 as described in the section Booting from McSPI

Please take a look at let us know if you have any follow up questions.

Regards,

Rahul

Thanks for confirming that you are able to flash and boot from SPI flash on the ICE AM335x.

Yes, when you create your own board, you will need to update the bootloader code to account for the change in DDR and flash.

The RBL is programmed in the silicon, it is designed to initialize clocks and boot media and then just copy over the secondary bootloader to OCMC memory. all of the customization will need to be done in the secondary bootloader. The source for the secondary bootloader is provided in the SDK at the location : pdk_am335x_1_0_8\packages\ti\starterware\bootloader

DDR Configuration: bootloader\src\am335x\sbl_am335x_platform_ddr.c
Flash media configuration : bootloader\src\ sbl_<boot interface>.c

When the bootloader builds, it creates four files, .out, .bin, _ti.bin and .map file. The .out file for the bootloader can be loaded on the device and debugged like any other application. Since SBL runs post boot, you can customize the interface speeds as per your application requirements.

The boot sequence configured on the AM335x ICE has SPI before, SSD/MMC so if you have a valid image on the SPI flash, the RBL will not proceed to SD/MMC boot mode. To be able to boot from SD card again, you need to erase the flash at address 0x00000. Rerun the flash writer and select thte option to erase and erase 1 sectore (4KB) on the SPI flash at offset 0x000000 and then you should be able to boot from SD card again.

Regards,
Rahul