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Re: printf does not work in user mode on Arm E7T
Pierre Habraken wrote:
I just compiled and ran the test program (sources below) on the E7T
board, using this time Angel and RDI instead of Redboot: the Arm BL
instructions (and thus the call to printf) executes perfectly when the
processor is in user mode. As BL fails to execute when the program is
run against Redboot, I understand that something in the latter goes
wrong as regards user mode execution.
Can someone tell me where I could look in Redboot code in order to
understand the problem ???
Use "set debug remote 1" in GDB and try and find out if anything is not
right in the traffic there. After that you should look in hal/common's
generic-stub.c which is where the GDB packets get read and mostly acted on.
Finally, there's arm/arch's arm_stub.c which contains code to determine
the next PC on a single step. That's definitely worth a look given your
problem, although the odd thing is how this works for others, but maybe
something changed a while back and no-one's noticed yet! I don't have an
arm target here to test I'm afraid.
Jifl
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