x86 passthru:: graphics passthrough

This patch supports basic gfx passthrough on xen side:
  - add a VGA type for gfx passthrough, and get the size of VGA bios
  of passthrouged gfx in hvmloader
  - add a config option 'gfx_passthru' for gfx passthrough

Signed-off-by: Ben Lin <ben.y.lin@intel.com>
Signed-off-by: Weidong Han <weidong.han@intel.com>

tools/python/xen/xend/XendConfig.py

@@ -175,6 +175,7 @@ XENAPI_PLATFORM_CFG_TYPES = {
     'pci_msitranslate': int,
     'pci_power_mgmt': int,
     'xen_platform_pci': int,
+    "gfx_passthru": int,
 }
 
 # Xen API console 'other_config' keys.

tools/python/xen/xend/image.py

@@ -807,7 +807,7 @@ class HVMImageHandler(ImageHandler):
 
         dmargs = [ 'boot', 'fda', 'fdb', 'soundhw',
                    'localtime', 'serial', 'stdvga', 'isa',
-                   'acpi', 'usb', 'usbdevice' ]
+                   'acpi', 'usb', 'usbdevice', 'gfx_passthru' ]
 
         for a in dmargs:
             v = vmConfig['platform'].get(a)

tools/python/xen/xm/create.py

@@ -547,6 +547,10 @@ gopts.var('sdl', val='',
           fn=set_value, default=None,
           use="""Should the device model use SDL?""")
 
+gopts.var('gfx_passthru', val='',
+          fn=set_value, default=None,
+          use="""Passthrough graphics card?""")
+
 gopts.var('opengl', val='',
           fn=set_value, default=None,
           use="""Enable\Disable OpenGL""")
@@ -957,7 +961,8 @@ def configure_hvm(config_image, vals):
              'acpi', 'apic', 'usb', 'usbdevice', 'keymap', 'pci', 'hpet',
              'guest_os_type', 'hap', 'opengl', 'cpuid', 'cpuid_check',
              'viridian', 'xen_extended_power_mgmt', 'pci_msitranslate',
-             'vpt_align', 'pci_power_mgmt', 'xen_platform_pci' ]
+             'vpt_align', 'pci_power_mgmt', 'xen_platform_pci',
+             'gfx_passthru' ]
 
     for a in args:
         if a in vals.__dict__ and vals.__dict__[a] is not None: