Martin's QEMU bits

Martin Guy, <martinwguy@yahoo.it>

Last updated: 2006-09-27.

I've been patching QEMU to make it run an ARM EABI kernel for the Debian ARM EABI architecture project.

To run QEMU in full-system emulation mode you need at least qemu-0.8.1 (which is currently the lastest in debian testing).

To run a single ARM EABI process in user-emulation mode, you need to apply pbrook's TLS patches. Those patches do not apply automatically with patch, so here is a repackaged version that applies automatically:

	$ tar xfz qemu-0.8.2.tar.gz
	$ cd qemu-0.8.2
	$ patch -p1 < ../patch.qemu*-mg1

Note that these patches are not yet complete and may give subtle failures in programs that use threads heavily.

Fetch, patch, build, install QEMU

I fetch and patch it with

wget http://qemu.org/qemu-0.8.2.tar.gz
tar xfz qemu-0.8.2.tar.gz
cd qemu-0.8.2
patch -p1 < ../patch.qemu*mg1

then build and install it (under /usr/local) with

./configure --cc=gcc-3.4 --host_cc=gcc-3.4 --disable-gfx-check --target-list=arm-user,arm-softmmu
make
make install

Kernel

You also need

a tiny patch to linux-2.6.16 to enable the ARM 1022 and 1026 processors, as used in the only ARM system board emulated by QEMU, the ARM Integrator/CP
and here is pbrook's linux-2.6.16 ARM EABI kernel config for QEMU. pbrook says of this config:
This includes framebuffer support, so you'll may want to add -append "console=ttyAMA0"

I currently build the kernel as part of a crosstool run, fishing the zImage out of build/*/*/linux*/arch/arm/boot, and modifying the arm-test system from QEMU's home page to use this kernel with the old-ABI busybox userland with the command

	qemu-system-arm -kernel zImage.pbrook -M integratorcp1026 \
	   -initrd arm_root.img -nographic -append console=ttyAMA0

which boots into a shell prompt.

On slow machines (400MHz Pentium II), the kernel says it has detected a lockup and barfs stack backtraces but this deosn't happen when running it on faster machines (2 GHz Athlon).

Almost every command says "Using fallback suid method" before running, but that is a busybox configuration issue, not our problem.