Fiasco.OC and qemu vexpress machine model

[Michele Paolino]

Hello l4hackers,

I'm trying to execute Fiasco.OC along with the hello module using qemu 
and the vexpress machine model. For both A9 and A15 cpus the system 
hangs at "Starting kernel fiasco". It seems that something (the UART 
driver?) prevents the system to log the kernel boot to the screen.

I compiled the image using 'make qemu' in L4RE, and the vm is executed 
with the argument -nographic.

Can you confirm this? Do you have any suggestion to solve it?

Here below you can find the log of the A15 boot process:

L4 Bootstrapper
   Build: #2 Thu Apr 10 12:50:53 CEST 2014, 4.6.3
   Scanning up to 256 MB RAM
   Memory size is 256MB (80000000 - 8fffffff)
   RAM: 0000000080000000 - 000000008fffffff: 262144kB
   Total RAM: 256MB
   mod04: 810bc000-810d5580: hello
   mod03: 810a2000-810bb460: l4re
   mod02: 81070000-810a162c: moe
   mod01: 81066000-8106f344: sigma0
   mod00: 81014000-810652e0: fiasco
   Moving up to 5 modules behind 81100000
   moving module 00 { 81014000-810652df } -> { 811c2000-812132df } [332512]
   moving module 01 { 81066000-8106f343 } -> { 81214000-8121d343 } [37700]
   moving module 02 { 81070000-810a162b } -> { 8121e000-8124f62b } [202284]
   moving module 03 { 810a2000-810bb45f } -> { 81100000-8111945f } [103520]
   moving module 04 { 810bc000-810d557f } -> { 8111a000-8113357f } [103808]
   Scanning fiasco -serial_esc
   Scanning sigma0  Scanning moe --init=rom/hello
   Relocated mbi to [0x8100d000-0x8100d0e2]
   Loading fiasco
   Loading sigma0
   Loading moe
   find kernel info page...
   found kernel info page at 0x80002000
Regions of list 'regions'
     [ 80001000,  80001cbf] {      cc0} Kern   fiasco
     [ 80002000,  8005efff] {    5d000} Kern   fiasco
     [ 80090000,  800963c3] {     63c4} Sigma0 sigma0
     [ 80098000,  8009e17b] {     617c} Sigma0 sigma0
     [ 80140000,  8016ba6b] {    2ba6c} Root   moe
     [ 80170000,  80186f0f] {    16f10} Root   moe
     [ 81000000,  810133f7] {    133f8} Boot   bootstrap
     [ 81009000,  810090a6] {       a7} Boot   mbi
     [ 8100d000,  8100d1df] {      1e0} Root   Multiboot info
     [ 8101304c,  810130a3] {       58} Boot   mbi
     [ 81100000,  8113357f] {    33580} Root   Module
   API Version: (87) experimental
   Sigma0 config    ip:80090100 sp:81012de4
   Roottask config  ip:801401a0 sp:00000000
   Starting kernel fiasco at 800013b0

Regards,
Michele Paolino