spapr: add dumpdtb support

dumpdtb (-machine dumpdtb=<file>) allows one to inspect the generated
device tree of machine types that generate device trees. This is
useful for a) seeing what's there b) debugging/testing device tree
generator patches. It can be used as follows

$QEMU_CMDLINE -machine dumpdtb=dtb
dtc -I dtb -O dts dtb

Signed-off-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 2 insertions, 0 deletions

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index ed0abd8..a69d7e4 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -30,6 +30,7 @@
 #include "hw/fw-path-provider.h"
 #include "elf.h"
 #include "net/net.h"
+#include "sysemu/device_tree.h"
 #include "sysemu/block-backend.h"
 #include "sysemu/cpus.h"
 #include "sysemu/kvm.h"
@@ -831,6 +832,7 @@ static void spapr_finalize_fdt(sPAPRMachineState *spapr,
         exit(1);
     }
 
+    qemu_fdt_dumpdtb(fdt, fdt_totalsize(fdt));
     cpu_physical_memory_write(fdt_addr, fdt, fdt_totalsize(fdt));
 
     g_free(bootlist);