Re: [Qemu-ppc] Fwd: running qemu for powerpc (32bits) architecture

[Scott Wood]

[Moved to the QEMU list and CCed Alex Graf]

On Sun, 2016-06-05 at 12:32 +0100, Marwa Hamza wrote:
> 
> ---------- Forwarded message ----------
> From: Scott Wood <address@hidden>
> Date: 2016-06-04 1:23 GMT+01:00
> Subject: Re: running qemu for powerpc (32bits) architecture
> To: Marwa Hamza <address@hidden>, address@hidden
> 
> 
> On Mon, 2016-05-30 at 10:04 +0100, Marwa Hamza wrote:
> > hello everyone
> > I'm trying to run qemu for powerpc architecture but either
> > 1/ i got a black screen with this sentence " QEMU 2.4.0.1 monitor - type
> > help for more information"
> >                        (QEMU)
> > if i run this command ./ppc-softmmu/qemu-system-ppc -M ppce500 -kernel
> > ../linux-4.4.1/arch/powerpc/boot/zImage -initrd powerpc/busybox
> > -1.21.0/rootfs.img.gz -append "root=/dev/ram rdinit=/bin/sh"
> 
> I can't help with the other platforms, but for ppce500, make sure you have
> CONFIG_PPC_QEMU_E500 enabled in the kernel (and that it's an e500 build, of
> course), pass either uImage or vmlinux (not zImage) to -kernel, and specify
> the desired cpu type on the QEMU command line (using -cpu) to match the type
> of kernel you built.  I recommend using e500mc rather than older e500
> because
> then you get standard floating point which your RFS may depend on.
> 
> Also note that this target will have a serial port for output, not a
> display,
> so configure QEMU appropriately with -serial for how you want to access
> that.
> 
> If you need more help (especially with other PPC platforms) I suggest the
> address@hidden mailing list.
> 
> -Scott
> 
> 
> 
> hey
> i tried what you said, 
> ./ppc-softmmu/qemu-system-ppc -M ppce500 -kernel /home/powerpc/linux
> -4.4.1/vmlinux -initrd /home/busybox-1.21.0/rootfs.img.gz -append
> "root=/dev/ram console=ttyAMA0 rdinit=/sbin/init" -serial stdio -cpu e500mc
> an error displayed Qemu can't load kernel vmlinux

Try uImage and/or a stripped vmlinux.  It looks like commit 3812c71ff ("PPC:
e500: Move to u-boot as firmware") tries to put the entire kernel image into
guest memory even if U-Boot is not being used, and your vmlinux might be too
big for that.

What is "ttyAMA0"?

> other thing i didn't understand how i made sure that CONFIG_PPC_QEMU_E500
> enabled in the kernel, what is the default configuration should i use?
> what's the e500 build ? 

e500 is a type of PPC core.  e500mc is a type of e500 that has normal floating
point.  Use corenet32_smp_defconfig and then manually enable
CONFIG_PPC_QEMU_E500 (we really ought to add that to the defconfig), and pass 
-cpu e500mc to QEMU.

-Scott