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Memory Access of secondary core in U-Boot

Question asked by Mirko Liebender on Oct 19, 2016
Latest reply on Jan 2, 2017 by Mirko Liebender

Hello,

 

I'm using a P4080 Rev 2.0 and I'm trying to get the secondary core to run some standalone code. 

The code is rather simple, accesses a memory location and writes some data.

e.g.:

 

unsigned long volatile * const data_addr = (unsigned long*) 0x0;
*data_addr = 0xffffffff;

This would write 0xffffffff to memory location 0x0.

I'm using the U-Boot command "cpu 1 release ADDR - - -" to get the core out of spin to start the program. ADDR is the memory location of the standalone application. Until this point everything works. The code even executes (BDI3000 tells me, that the pc is set correctly and running...I even confirmed that by changing some registers and reading them via debugger).

My problem is the memory access. I'm not very familiar with the memory subsystem of the P4080 and I guess there are some more steps necessary to be able to access memory, but maybe you could point me in the right direction.

Thanks in advance.

 

Regards, Mirko

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