= QEMU =


You can run RTEMS in the open source processor emulator [http://fabrice.bellard.free.fr/qemu/ QEMU]. The QEMU emulator runs on a number of hosts including Linux and Windows. It also supports a number of [http://fabrice.bellard.free.fr/qemu/status.html processors].
= QEMU PC Emulator =


The RTEMS PC BSP runs in the QEMU emulator.
= Making a Boot Floppy Disk =


We RTEMS in QEMU by first booting from a floppy disk image. You can use the image we have made by downloading it from the RTEMS ftp server. The following instructions built the image and were run on a Fedora Core 5 Linux host.

Download the latest release of version 2 the [http://grub.enbug.org/FrontPage Grub boot loader] from [ftp://alpha.gnu.org/gnu/grub/]. Build the package with the following configure command:

  $ ../grub-1.94/configure --prefix=/tmp/g2/build
  $ make all install

where the prefix can be anything suitable for your machine. If configure fails with a missing LZO library check you have the lzo-devel package installed.

To make the floppy image follow the instructions in the Grub Wiki at http://grub.enbug.org/TestingOnX86. This script is adapted from the instructions:

 #! /bin/sh -x
 grub=/tmp/g2/build
 workspace=/tmp/g2
 mnt=$workspace/mnt/loop
 file=$workspace/rtems-boot.img
 export PATH=$grub/bin:$grub/sbin:$PATH
 mkdir -p $workspace
 cd $workspace
 grub-mkimage -o core.img _chain ls pc multiboot gpt fat boot reboot configfile cat help
 dd if=/dev/zero of=$file bs=512 count=2880
 /sbin/mkdosfs $file
 mkdir -p $mnt
 mount -o loop -t vfat $file $mnt
 mkdir -p $mnt/boot/grub
 cp $grub/lib/grub/i386-pc/boot.img core.img $grub/lib/grub/i386-pc/*.mod $mnt/boot/grub
 cat "configfile (hd0,0)/rtems-grub.cfg" > $mnt/boot/grub/grub.cfg
 echo '(fd0)' $file > tmp_device.map
 grub-setup -d $mnt/boot/grub -r '(fd0)' -m tmp_device.map '(fd0)'
 rm -f tmp_device.map
 umount $mnt

The default '''grub.cfg''' file will attempt to read a GRUB configuration file called '''rtems-grub.cfg''' from the root directory of the harddisk. This lets you create a specific GRUB configuration for you testing without needing to rebuild the floppy image. An example configuration that lets you run the RTEMS Samples is:

 # RTEMS Grub configuration for the Samples
 
 set default=0
 
 menuentry "RTEMS - Hello" {
  set root=(hd0,0)
  multiboot (hd0,0)/hello/hello.exe
 }
 
 menuentry "RTEMS - Ticker" {
  set root=(hd0,0)
  multiboot (hd0,0)/ticker/ticker.exe
 }
 
 menuentry "RTEMS - Minimum" {
  set root=(hd0,0)
  multiboot (hd0,0)/minimum/minimum.exe
 }
 
 menuentry "RTEMS - Paranoia" {
  set root=(hd0,0)
  multiboot (hd0,0)/paranoia/paranoia.exe
 }
 
 menuentry "RTEMS - File IO" {
  set root=(hd0,0)
  multiboot (hd0,0)/fileio/fileio.exe
 }
 
 menuentry "RTEMS - Unlimited" {
  set root=(hd0,0)
  multiboot (hd0,0)/unlimited/unlimited.exe
 }
 
 menuentry "RTEMS - Loopback" {
  set root=(hd0,0)
  multiboot (hd0,0)/loopback/loopback.exe
 }
 
 menuentry "RTEMS - PPPD" {
  set root=(hd0,0)
  multiboot (hd0,0)/pppd/pppd.exe
 }
  
 menuentry "RTEMS - Base Mulitprocessor" {
  set root=(hd0,0)
  multiboot (hd0,0)/base_mp/base_mp.exe
 }
 
 menuentry "RTEMS - Base Single Processor" {
  set root=(hd0,0)
  multiboot (hd0,0)/base_sp/base_sp.exe
 }
 
 menuentry "RTEMS - C++ Static Constructors" {
  set root=(hd0,0)
  multiboot (hd0,0)/cdtest/cdtest.exe
 }
 
 menuentry "RTEMS - C++ IO Streams" {
  set root=(hd0,0)
  multiboot (hd0,0)/iostream/iostream.exe
 }