Part Number:SECDEVTOOL-OMAPL138C6748
Hi there,
I am writing a DSP secondary bootloader for secure enabled OMAP-L138 chip and having problem with loading code sections to ARM Local RAM from DSP.
To clarify, when I analyze the content of the ARM+DSP binary application image, there are two sections of code that must be located in ARM local RAM (0xFFFF0000 - 0xFFFFFFFF) during booting process (as showed in bellow).
However, in the datasheet of OMAP-L138, this region of memory can only be accessed from ARM or PRU core. As showed in table 3-4 (page 24), the gray color indicates that DSP cannot directly read from or write to this range of memory.
Therefore, the boot process always suspend when I try to load code/data to ARM local RAM from DSP secondary bootloader (as showed in UART debug screen bellow)
QUESTIONS:
1. I know that I can use PRU0 to load data from SHARED_RAM/DDR_RAM to ARM local RAM, but I don't know how to program it. Could anyone provide me with a PRU code to perform this task?
2. Is there another way to solve this problem, which does not use an ARM secondary bootloader?
Thanks in advance,