From: Daniel P. Berrangé <berra...@redhat.com> Currently QEMU defaults to a resolution of 1024x768 when exposing EDID info to the guest OS. The EDID default info is important as this will influence what resolution many guest OS will configure the screen with on boot. It can also potentially influence what resolution the firmware will configure the screen with, though until very recently EDK2 would not handle EDID info.
One important thing to bear in mind is that the default graphics card driver provided by Windows will leave the display set to whatever resolution was enabled by the firmware on boot. Even if sufficient VRAM is available, the resolution can't be changed without installing new drivers. IOW, the default resolution choice is quite important for usability of Windows. Modern real world monitor hardware for desktop/laptop has supported resolutions higher than 1024x768 for a long time now, perhaps as long as 15+ years. There are quite a wide variety of native resolutions in use today, however, and in wide screen form factors the height may not be all that tall. None the less, it is considered that there is scope for making the QEMU default resolution slightly larger. In considering what possible new default could be suitable, choices considered were 1280x720 (720p), 1280x800 (WXGA) and 1280x1024 (SXGA). In many ways, vertical space is the most important, and so 720p was discarded due to loosing vertical space, despite being 25% wider. The SXGA resolution would be good, but when taking into account window titlebars/toolbars and window manager desktop UI, this might be a little too tall for some users to fit the guest on their physical montior. This patch thus suggests a modest change to 1280x800 (WXGA). This only consumes 1 MB per colour channel, allowing double buffered framebuffer in 8 MB of VRAM. Width wise this is 25% larger than QEMU's current default, but height wise this only adds 5%, so the difference isn't massive on the QEMU side. Overall there doesn't appear to be a compelling reason to stick with 1024x768 resolution. Signed-off-by: Daniel P. Berrangé <berra...@redhat.com> Reviewed-by: Gerd Hoffmann <kra...@redhat.com> Message-Id: <20211129140508.1745130-1-berra...@redhat.com> Signed-off-by: Gerd Hoffmann <kra...@redhat.com> --- include/hw/virtio/virtio-gpu.h | 4 ++-- hw/display/edid-generate.c | 4 ++-- qemu-edid.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/include/hw/virtio/virtio-gpu.h b/include/hw/virtio/virtio-gpu.h index acfba7c76c10..2179b757037a 100644 --- a/include/hw/virtio/virtio-gpu.h +++ b/include/hw/virtio/virtio-gpu.h @@ -147,8 +147,8 @@ struct VirtIOGPUBaseClass { DEFINE_PROP_UINT32("max_outputs", _state, _conf.max_outputs, 1), \ DEFINE_PROP_BIT("edid", _state, _conf.flags, \ VIRTIO_GPU_FLAG_EDID_ENABLED, true), \ - DEFINE_PROP_UINT32("xres", _state, _conf.xres, 1024), \ - DEFINE_PROP_UINT32("yres", _state, _conf.yres, 768) + DEFINE_PROP_UINT32("xres", _state, _conf.xres, 1280), \ + DEFINE_PROP_UINT32("yres", _state, _conf.yres, 800) typedef struct VGPUDMABuf { QemuDmaBuf buf; diff --git a/hw/display/edid-generate.c b/hw/display/edid-generate.c index f2b874d5e358..6f5ac6a38ad8 100644 --- a/hw/display/edid-generate.c +++ b/hw/display/edid-generate.c @@ -401,10 +401,10 @@ void qemu_edid_generate(uint8_t *edid, size_t size, info->name = "QEMU Monitor"; } if (!info->prefx) { - info->prefx = 1024; + info->prefx = 1280; } if (!info->prefy) { - info->prefy = 768; + info->prefy = 800; } if (info->prefx >= 4096 || info->prefy >= 4096) { large_screen = 1; diff --git a/qemu-edid.c b/qemu-edid.c index c3a9fba10dc4..20c958d9c7eb 100644 --- a/qemu-edid.c +++ b/qemu-edid.c @@ -10,8 +10,8 @@ #include "hw/display/edid.h" static qemu_edid_info info = { - .prefx = 1024, - .prefy = 768, + .prefx = 1280, + .prefy = 800, }; static void usage(FILE *out) -- 2.34.1