[PATCH] hw/misc: deprecate the 'sga' device

[PATCH] hw/misc: deprecate the 'sga' device

[Daniel P. Berrangé]

This is obsolete since SeaBIOS 1.11.0 introduced native support for
sending messages to the serial console. The new support can be
activated using -machine graphics=off on x86 targets.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 docs/about/deprecated.rst | 10 ++++++++++
 hw/misc/sga.c             |  2 ++
 2 files changed, 12 insertions(+)

diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 9ee355ec0b..cafca05826 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -280,6 +280,16 @@ full SCSI support.  Use virtio-scsi instead when SCSI passthrough is required.
 Note this also applies to ``-device virtio-blk-pci,scsi=on|off``, which is an
 alias.
 
+``-device sga`` (since 6.2)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The ``sga`` device loads an option ROM for x86 targets which enables
+SeaBIOS to send messages to the serial console. SeaBIOS 1.11.0 onwards
+contains native support for this feature and thus use of the option
+ROM approach is obsolete. The native SeaBIOS support can be activated
+by using ``-machine graphics=off``.
+
+
 Block device options
 ''''''''''''''''''''
 
diff --git a/hw/misc/sga.c b/hw/misc/sga.c
index 4dbe6d78f9..1d04672b01 100644
--- a/hw/misc/sga.c
+++ b/hw/misc/sga.c
@@ -30,6 +30,7 @@
 #include "hw/loader.h"
 #include "qemu/module.h"
 #include "qom/object.h"
+#include "qemu/error-report.h"
 
 #define SGABIOS_FILENAME "sgabios.bin"
 
@@ -42,6 +43,7 @@ struct ISASGAState {
 
 static void sga_realizefn(DeviceState *dev, Error **errp)
 {
+    warn_report("-device sga is deprecated, use -machine graphics=off");
     rom_add_vga(SGABIOS_FILENAME);
 }
 
-- 
2.31.1

Re: [PATCH] hw/misc: deprecate the 'sga' device

[Gerd Hoffmann]

On Thu, Sep 09, 2021 at 01:32:19PM +0100, Daniel P. Berrangé wrote:
> This is obsolete since SeaBIOS 1.11.0 introduced native support for
> sending messages to the serial console. The new support can be
> activated using -machine graphics=off on x86 targets.
> 
> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>