[Buildroot] [PATCH v2] manual: add QEMU demo to quick start

[Ciro Santilli <ciro.santilli@gmail.com>]

---
OK, me learning to ues crappy mailing lists now >:-), will this appear v2
on the same thread?

Your software is awesome, and many more people would see that if the
quickstart actually told them how to quickstart and see something happen ;-)

 docs/manual/quickstart.txt | 36 +++++++++++++++++++++++++++++++-----
 1 file changed, 31 insertions(+), 5 deletions(-)

diff --git a/docs/manual/quickstart.txt b/docs/manual/quickstart.txt
index 74158ae249..00afe09e6b 100644
--- a/docs/manual/quickstart.txt
+++ b/docs/manual/quickstart.txt
@@ -8,12 +8,38 @@ is no need to be root to configure and use Buildroot. By running all
 commands as a regular user, you protect your system against packages
 behaving badly during compilation and installation.
 
-The first step when using Buildroot is to create a configuration.
-Buildroot has a nice configuration tool similar to the one you can
-find in the http://www.kernel.org/[Linux kernel] or in
-http://www.busybox.net/[BusyBox].
+=== Try it out with QEMU
 
-From the buildroot directory, run
+If you just want to emulate a simple generic QEMU system to see
+Buildroot at work immediately, run from the buildroot directory:
+
+--------------------
+make qemu_x86_64_defconfig
+make BR2_JLEVEL="$(nproc)"
+qemu-system-x86_64 \
+  -M pc \
+  -kernel output/images/bzImage \
+  -drive file=output/images/rootfs.ext2,if=virtio,format=raw \
+  -append "root=/dev/vda" \
+  -net nic,model=virtio \
+  -net user
+--------------------
+
+Once QEMU boots, login with +root+, and you are now left inside a minimal
+BusyBox based Linux distribution.
+
+The initial build can take several minutes to a few hours since we download
+and compile GCC, the Linux kernel and other basic system components from
+source.
+
+The QEMU command to use is also documented at: +board/qemu/x86/readme.txt+
+
+=== Day-to-day workflow
+
+In your day-to-day workflow, the first step when using Buildroot is to
+create a custom configuration. Buildroot has a nice configuration tool
+similar to the one you can find in the http://www.kernel.org/[Linux kernel]
+or in http://www.busybox.net/[BusyBox]:
 
 --------------------
  $ make menuconfig
-- 
2.19.0