[PULL 1/1] qxl: introduce hardware revision 5

[Gerd Hoffmann <kraxel@redhat.com>]

The only difference to hardware revision 4 is that the device doesn't
switch to VGA mode in case someone happens to touch a VGA register,
which should make things more robust in configurations with multiple
vga devices.

Swtiching back to VGA mode happens on reset, either full machine
reset or qxl device reset (QXL_IO_RESET ioport command).

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-id: 20200206074358.4274-1-kraxel@redhat.com
---
 hw/display/qxl.h  | 2 +-
 hw/core/machine.c | 2 ++
 hw/display/qxl.c  | 7 ++++++-
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/hw/display/qxl.h b/hw/display/qxl.h
index 80eb0d267269..707631a1f573 100644
--- a/hw/display/qxl.h
+++ b/hw/display/qxl.h
@@ -144,7 +144,7 @@ typedef struct PCIQXLDevice {
         }                                                               \
     } while (0)
 
-#define QXL_DEFAULT_REVISION QXL_REVISION_STABLE_V12
+#define QXL_DEFAULT_REVISION (QXL_REVISION_STABLE_V12 + 1)
 
 /* qxl.c */
 void *qxl_phys2virt(PCIQXLDevice *qxl, QXLPHYSICAL phys, int group_id);
diff --git a/hw/core/machine.c b/hw/core/machine.c
index d8e30e4895d8..84812a1d1cc1 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -34,6 +34,8 @@ GlobalProperty hw_compat_4_2[] = {
     { "vhost-blk-device", "seg_max_adjust", "off"},
     { "usb-host", "suppress-remote-wake", "off" },
     { "usb-redir", "suppress-remote-wake", "off" },
+    { "qxl", "revision", "4" },
+    { "qxl-vga", "revision", "4" },
 };
 const size_t hw_compat_4_2_len = G_N_ELEMENTS(hw_compat_4_2);
 
diff --git a/hw/display/qxl.c b/hw/display/qxl.c
index c33b1915a52c..64884da70857 100644
--- a/hw/display/qxl.c
+++ b/hw/display/qxl.c
@@ -1309,7 +1309,8 @@ static void qxl_vga_ioport_write(void *opaque, uint32_t addr, uint32_t val)
     PCIQXLDevice *qxl = container_of(vga, PCIQXLDevice, vga);
 
     trace_qxl_io_write_vga(qxl->id, qxl_mode_to_string(qxl->mode), addr, val);
-    if (qxl->mode != QXL_MODE_VGA) {
+    if (qxl->mode != QXL_MODE_VGA &&
+        qxl->revision <= QXL_REVISION_STABLE_V12) {
         qxl_destroy_primary(qxl, QXL_SYNC);
         qxl_soft_reset(qxl);
     }
@@ -2121,6 +2122,10 @@ static void qxl_realize_common(PCIQXLDevice *qxl, Error **errp)
         pci_device_rev = QXL_REVISION_STABLE_V12;
         io_size = pow2ceil(QXL_IO_RANGE_SIZE);
         break;
+    case 5: /* qxl-5 */
+        pci_device_rev = QXL_REVISION_STABLE_V12 + 1;
+        io_size = pow2ceil(QXL_IO_RANGE_SIZE);
+        break;
     default:
         error_setg(errp, "Invalid revision %d for qxl device (max %d)",
                    qxl->revision, QXL_DEFAULT_REVISION);
-- 
2.18.2