This change allows creating contexts of depending on set of context parameters. The meaning of each of the parameters is listed below:
1) VIRTGPU_CONTEXT_PARAM_CAPSET_ID
This determines the type of a context based on the capability set ID. For example, the current capsets:
VIRTIO_GPU_CAPSET_VIRGL VIRTIO_GPU_CAPSET_VIRGL2
define a Gallium, TGSI based "virgl" context. We only need 1 capset ID per context type, though virgl has two due a bug that has since been fixed.
The use case is the "gfxstream" rendering library and "venus" renderer.
gfxstream doesn't do Gallium/TGSI translation and mostly relies on auto-generated API streaming. Certain users prefer gfxstream over virgl for GLES on GLES emulation. {gfxstream vk}/{venus} are also required for Vulkan emulation. The maximum capset ID is 63.
The goal is for guest userspace to choose the optimal context type depending on the situation/hardware.
2) VIRTGPU_CONTEXT_PARAM_NUM_RINGS
This tells the number of independent command rings that the context will use. This value may be zero and is inferred to be zero if VIRTGPU_CONTEXT_PARAM_NUM_RINGS is not passed in. This is for backwards compatibility for virgl, which has one big giant command ring for all commands.
The maxiumum number of rings is 32. In practice, multi-queue or multi-ring submission is used for powerful dGPUs and virtio-gpu may not be the best option in that case (see PCI passthrough or rendernode forwarding).
3) VIRTGPU_CONTEXT_PARAM_POLL_RING_IDX_MASK
This is a mask of ring indices for which the DRM fd is pollable. For example, if VIRTGPU_CONTEXT_PARAM_NUM_RINGS is 2, then the mask may be:
[ring idx] | [1 << ring_idx] | final mask ------------------------------------------- 0 1 1 1 2 3
The "Sommelier" guest Wayland proxy uses this to poll for events from the host compositor.
Signed-off-by: Gurchetan Singh gurchetansingh@chromium.org Acked-by: Lingfeng Yang lfy@google.com Acked-by: Nicholas Verne nverne@chromium.org --- include/uapi/drm/virtgpu_drm.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+)
diff --git a/include/uapi/drm/virtgpu_drm.h b/include/uapi/drm/virtgpu_drm.h index b9ec26e9c646..a13e20cc66b4 100644 --- a/include/uapi/drm/virtgpu_drm.h +++ b/include/uapi/drm/virtgpu_drm.h @@ -47,12 +47,15 @@ extern "C" { #define DRM_VIRTGPU_WAIT 0x08 #define DRM_VIRTGPU_GET_CAPS 0x09 #define DRM_VIRTGPU_RESOURCE_CREATE_BLOB 0x0a +#define DRM_VIRTGPU_CONTEXT_INIT 0x0b
#define VIRTGPU_EXECBUF_FENCE_FD_IN 0x01 #define VIRTGPU_EXECBUF_FENCE_FD_OUT 0x02 +#define VIRTGPU_EXECBUF_RING_IDX 0x04 #define VIRTGPU_EXECBUF_FLAGS (\ VIRTGPU_EXECBUF_FENCE_FD_IN |\ VIRTGPU_EXECBUF_FENCE_FD_OUT |\ + VIRTGPU_EXECBUF_RING_IDX |\ 0)
struct drm_virtgpu_map { @@ -68,6 +71,8 @@ struct drm_virtgpu_execbuffer { __u64 bo_handles; __u32 num_bo_handles; __s32 fence_fd; /* in/out fence fd (see VIRTGPU_EXECBUF_FENCE_FD_IN/OUT) */ + __u32 ring_idx; /* command ring index (see VIRTGPU_EXECBUF_RING_IDX) */ + __u32 pad; };
#define VIRTGPU_PARAM_3D_FEATURES 1 /* do we have 3D features in the hw */ @@ -75,6 +80,8 @@ struct drm_virtgpu_execbuffer { #define VIRTGPU_PARAM_RESOURCE_BLOB 3 /* DRM_VIRTGPU_RESOURCE_CREATE_BLOB */ #define VIRTGPU_PARAM_HOST_VISIBLE 4 /* Host blob resources are mappable */ #define VIRTGPU_PARAM_CROSS_DEVICE 5 /* Cross virtio-device resource sharing */ +#define VIRTGPU_PARAM_CONTEXT_INIT 6 /* DRM_VIRTGPU_CONTEXT_INIT */ +#define VIRTGPU_PARAM_SUPPORTED_CAPSET_IDs 7 /* Bitmask of supported capability set ids */
struct drm_virtgpu_getparam { __u64 param; @@ -173,6 +180,22 @@ struct drm_virtgpu_resource_create_blob { __u64 blob_id; };
+#define VIRTGPU_CONTEXT_PARAM_CAPSET_ID 0x0001 +#define VIRTGPU_CONTEXT_PARAM_NUM_RINGS 0x0002 +#define VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK 0x0003 +struct drm_virtgpu_context_set_param { + __u64 param; + __u64 value; +}; + +struct drm_virtgpu_context_init { + __u32 num_params; + __u32 pad; + + /* pointer to drm_virtgpu_context_set_param array */ + __u64 ctx_set_params; +}; + #define DRM_IOCTL_VIRTGPU_MAP \ DRM_IOWR(DRM_COMMAND_BASE + DRM_VIRTGPU_MAP, struct drm_virtgpu_map)
@@ -212,6 +235,10 @@ struct drm_virtgpu_resource_create_blob { DRM_IOWR(DRM_COMMAND_BASE + DRM_VIRTGPU_RESOURCE_CREATE_BLOB, \ struct drm_virtgpu_resource_create_blob)
+#define DRM_IOCTL_VIRTGPU_CONTEXT_INIT \ + DRM_IOWR(DRM_COMMAND_BASE + DRM_VIRTGPU_CONTEXT_INIT, \ + struct drm_virtgpu_context_init) + #if defined(__cplusplus) } #endif