On Thu, Aug 28, 2025 at 05:52:59PM +0000, Andrew Keesler wrote:
> In 454f4b0f, we started down the path of supporting separate
> configurations per display head (e.g., you have 2 heads - one with
> EDID name "AAA" and the other with EDID name "BBB").
>
> In this change, we add resolution to this configuration surface (e.g.,
> you have 2 heads - one with resolution 111x222 and the other with
> resolution 333x444).
>
> -display vnc=localhost:0,id=aaa,display=vga,head=0 \
> -display vnc=localhost:1,id=bbb,display=vga,head=1 \
> -device '{"driver":"virtio-vga",
> "max_outputs":2,
> "id":"vga",
> "outputs":[
> {
> "name":"AAA",
> "xres":111,
> "yres":222
> },
> {
> "name":"BBB",
> "xres":333,
> "yres":444
> }
> ]}'
>
> Here is the behavior matrix of the current resolution configuration
> surface (xres/yres) with the new resolution configuration surface
> (outputs[i].xres/yres).
>
> Case: !(xres || yres) && !(outputs[i].xres || outputs[i].yres)
> Behavior: current behavior - outputs[0] enabled with default xres/yres
>
> Case: (xres || yres) && !(outputs[i].xres || outputs[i].yres)
> Behavior: current behavior - outputs[0] enabled with xres/yres
>
> Case: !(xres || yres) && (outputs[i].xres || outputs[i].yres)
> Behavior: new behavior - outputs[i] enabled with outputs[i].xres/yres
>
> Case: (xres || yres) && (outputs[i].xres || outputs[i].yres)
> Behavior: new behavior - outputs[i] enabled with outputs[i].xres/yres
> ---
> hw/display/virtio-gpu-base.c | 10 ++++++++++
> include/hw/virtio/virtio-gpu.h | 2 ++
> qapi/virtio.json | 6 +++++-
> 3 files changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/hw/display/virtio-gpu-base.c b/hw/display/virtio-gpu-base.c
> index 7269477a1c..8bcbe5e837 100644
> --- a/hw/display/virtio-gpu-base.c
> +++ b/hw/display/virtio-gpu-base.c
> @@ -233,6 +233,16 @@ virtio_gpu_base_device_realize(DeviceState *qdev,
> g->req_state[0].width = g->conf.xres;
> g->req_state[0].height = g->conf.yres;
>
> + for (output_idx = 0, node = g->conf.outputs;
> + node && output_idx < g->conf.max_outputs;
> + output_idx++, node = node->next) {
> + if (node->value->xres || node->value->yres) {
This should be
if (node->value->has_xres && node->value->has_yres) {
> + g->enabled_output_bitmask |= (1 << output_idx);
> + g->req_state[output_idx].width = node->value->xres;
> + g->req_state[output_idx].height = node->value->yres;
> + }
> + }
> +
> g->hw_ops = &virtio_gpu_ops;
> for (i = 0; i < g->conf.max_outputs; i++) {
> g->scanout[i].con =
> diff --git a/include/hw/virtio/virtio-gpu.h b/include/hw/virtio/virtio-gpu.h
> index 9f16f89a36..7597e87971 100644
> --- a/include/hw/virtio/virtio-gpu.h
> +++ b/include/hw/virtio/virtio-gpu.h
> @@ -129,6 +129,8 @@ struct virtio_gpu_base_conf {
> uint32_t xres;
> uint32_t yres;
> uint64_t hostmem;
> + // If set, outputs[i].xres/yres takes precedent over xres/yres and
> enables
> + // the ith output.
I mean for that doc to be in the virtio.json file, so it gets into
the public QMP API documentation
> VirtIOGPUOutputList *outputs;
> };
>
> diff --git a/qapi/virtio.json b/qapi/virtio.json
> index 9d652fe4a8..9f753543cb 100644
> --- a/qapi/virtio.json
> +++ b/qapi/virtio.json
> @@ -970,11 +970,15 @@
> #
> # @name: the name of the output
> #
> +# @xres: horizontal resolution of the output in pixels (since 10.2)
> +#
> +# @yres: vertical resolution of the output in pixels (since 10.2)
> +#
> # Since: 10.1
> ##
>
> { 'struct': 'VirtIOGPUOutput',
> - 'data': { 'name': 'str' } }
> + 'data': { 'name': 'str', '*xres': 'uint16', '*yres': 'uint16' } }
>
> ##
> # @DummyVirtioForceArrays:
> --
> 2.51.0.338.gd7d06c2dae-goog
>
With regards,
Daniel
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