runqemu: try and guess qemu-system binary when MACHINE isn't set

Emulate some logic from the prior, shell based, version of runqemu
to try and infer the correct setting for MACHINE from the kernel
and rootfs filenames.

Signed-off-by: Joshua Lock <joshua.g.lock@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 36 insertions, 0 deletions

diff --git a/scripts/runqemu b/scripts/runqemu
index 5170d875707..591746f6570 100755
--- a/scripts/runqemu
+++ b/scripts/runqemu
@@ -846,9 +846,45 @@ class BaseConfig(object):
 
         self.set('ROOTFS_OPTIONS', self.rootfs_options)
 
+    def guess_qb_system(self):
+        """attempt to determine the appropriate qemu-system binary"""
+        mach = self.get('MACHINE')
+        if not mach:
+            search = '.*(qemux86-64|qemux86|qemuarm64|qemuarm|qemumips64|qemumips|qemuppc).*'
+            if self.rootfs:
+                match = re.match(search, self.rootfs)
+                if match:
+                    mach = match.group(1)
+            elif self.kernel:
+                match = re.match(search, self.kernel)
+                if match:
+                    mach = match.group(1)
+
+        if not mach:
+            return None
+
+        if mach == 'qemuarm':
+            qbsys = 'arm'
+        elif mach == 'qemuarm64':
+            qbsys = 'aarch64'
+        elif mach == 'qemux86':
+            qbsys = 'i386'
+        elif mach == 'qemux86-64':
+            qbsys = 'x86_64'
+        elif mach == 'qemuppc':
+            qbsys = 'ppc'
+        elif mach == 'qemumips':
+            qbsys = 'mips'
+        elif mach == 'qemumips64':
+            qbsys = 'mips64'
+
+        return 'qemu-system-%s' % qbsys
+
     def setup_final(self):
         qemu_system = self.get('QB_SYSTEM_NAME')
         if not qemu_system:
+            qemu_system = self.guess_qb_system()
+        if not qemu_system:
             raise Exception("Failed to boot, QB_SYSTEM_NAME is NULL!")
 
         qemu_bin = '%s/%s' % (self.get('STAGING_BINDIR_NATIVE'), qemu_system)