Re: [microblaze-uclinux] petalinux-v0.40-final released, and other news

[John Williams <john.williams@xxxxxxxxxxxxx>]

Hi Paul,

On Mon, Sep 14, 2009 at 4:55 AM, Paul Hartke <phartke@xxxxxxxxxxxx> wrote:

 

I'm familiar with QEMU from other contexts but the Microblaze support.  If you (and others) can share, I'm interested in how you are applying it and what problems it is helping to address.

One of the major innovations in the recent MicroBlaze kernels is the use of device trees - an abstract representation of the physical hardware system that is passed to the kernel at boot time to describe the complete hardware platform.  We've done the QEMU support for MicroBlaze so that the QEMU simulation model is itself driven by the same flat device tree, so you can simulate arbitrary MicroBlaze systems, address maps etc, driven by the same device tree as the kernel.

The win here is that is lets software developers get started very early, long before any hardware is ready.  We've put a lot of work into making the QEMU virtual networking as easy as possible, so you can test web and network apps inside the simulation environment.  You can even simulate multiple MicroBlaze systems on the same virtual network.

Anyone who remembers the old Virtual Platform that was shipped with a
few EDK versions will remember that it was very slow - booting a Linux
kernel took close to an hour of real time.  QEMU is fast - about 3-5
times faster than real HW in our experience.

The emulation is not limited to Linux, you can boot u-boot, or just about any MicroBlaze software under QEMU if you wish.  So, it will probably find use outside the Linux development flow.

Regards,

John
-- 
John Williams, PhD, B.Eng, B.IT
PetaLogix - Linux Solutions for a Reconfigurable World
w: www.petalogix.com  p: +61-7-30090663  f: +61-7-30090663