On 12/02/2016 07:40 AM, Tom Rini wrote:
Hey,
I'm trying to debug adding sh4 and r2dplus support to test.py. Until my current round of testing is applied you'll need http://patchwork.ozlabs.org/bundle/trini/fix-sh4-support-v2/ in order for us to get a functional U-Boot. After that, I have a "normal" conf file for the board for QEMU that looks like: console_impl=qemu qemu_machine="r2d" qemu_binary="qemu-system-sh4" qemu_extra_args="-nographic -serial null -serial mon:stdio" qemu_kernel_args="-kernel ${U_BOOT_BUILD_DIR}/u-boot.bin" reset_impl=none flash_impl=none
And here's where things get funny. When I kick off test.py with --bd r2dplus --id qemu --build -s -k sleep it will build and launch the board and since I have -s I can see stdio and I see U-Boot come up and give me the prompt, and then test.py says it times out waiting for the prompt. Any ideas where to poke next? I want to say something is funny with respect to what we see and where we see it (in terms of pipes) due to having to say -serial null -serial mon:stdio so that we see port #2 on the "board" rather than port #1 as this is the port that U-Boot and Linux use by default. Thanks!
Does "-serial null -serial mon:stdio" cause qemu to re-open file descriptors rather than just using stdout directly, or something like that? If so, perhaps its output is getting into the overall script's stdout (e.g. your terminal/console?) rather than the pipe that test/py is reading. If so, you'd see the qemu output but test/py wouldn't.
I think you can test this assumption by removing the -s option. If you still see qemu output, then qemu is sending it directly to wherever the overall stdout is going. If you no longer see qemu's output, then test/py must be reading it and only echo'ing it due to the -s option, and so you'd have to look somewhere else.
Is test/py waiting for the exact prompt that U-Boot is actually emitting?
In the past I've debugged such things by editing test/py/u_boot_spawn.py expect() to print some debug spew; I made it dump the current unmatched buffer content and the strings/regexes it was waiting for.