[RFC PATCH 2/7] drm/i915/gvt: Use meta fbs to stand for vGPU's planes
Zhang, Tina
tina.zhang at intel.com
Mon Dec 3 08:53:16 UTC 2018
> -----Original Message-----
> From: Zhenyu Wang [mailto:zhenyuw at linux.intel.com]
> Sent: Monday, December 3, 2018 4:21 PM
> To: Zhang, Tina <tina.zhang at intel.com>
> Cc: intel-gfx at lists.freedesktop.org; Kondapally, Kalyan
> <kalyan.kondapally at intel.com>; intel-gvt-dev at lists.freedesktop.org; Wang, Zhi
> A <zhi.a.wang at intel.com>
> Subject: Re: [RFC PATCH 2/7] drm/i915/gvt: Use meta fbs to stand for vGPU's
> planes
>
> On 2018.12.03 15:35:17 +0800, Tina Zhang wrote:
> > Create and initialize vGPU meta framebuffers during vGPU's creation.
> > Each meta framebuffer is an intel_framebuffer. Userspace can get the
> > userspace visible identifier of that meta framebuffer by accessing
> > plane_id_index attribute.
> >
> > For example:
> > In "/sys/bus/pci/devices/0000\:00\:02.0/$vGPU_id/intel_vgpu/"
> > directory,
> >
> > /* plane_id_index: pipe#(bit16:8) and plane#(bit7:0)*/
> > echo "0x10" > plane_index_id //Set the index to the plane 0 of pipe
> > 1
> >
> > /*
> > * Dump userspace visible identifier of the meta framebuffer
> > * standing for the primary plane of the vGPU's pipe one
> > */
> > cat plane_index_id //dump the id for plane 0 of pipe 1
> >
> > Then userspace can use this id with the exsting KMS IOCTL, e.g.
> > drmModeSetPlane, to assign a physical plane to this virtual plane.
>
> How does user know which plane/pipe is active for vGPU? Looks from current
> code it has no way to know that. I think for guest display assignment, we need
> to know the display state of vGPU and it looks there's no state tracking, e.g what
> if guest driver switches to another plane for display? How could user know that
> then adjust for assignment?
So far, GVT-g has supported multi-heads. In another word, there is only one priramy
plane for each vGPU.
GVT-g only provides the EDID for one fixed display port and in the guest point
of view, there is only one pipe having a connected monitor, a.k.a only the planes on
one pipe can be used by guest OS.
>
> And really don't like sysfs to r/w file for id, even if doesn't use vfio gfx dmabuf
> interface for guest display object presentation, a vendor specific vfio device ioctl
> if possible is better.
Yeah, we could consider about that.
Thanks.
BR,
Tina
>
> >
> > Signed-off-by: Tina Zhang <tina.zhang at intel.com>
> > Cc: Zhenyu Wang <zhenyuw at linux.intel.com>
> > Cc: Zhi Wang <zhi.a.wang at intel.com>
> > ---
> > drivers/gpu/drm/i915/gvt/display.c | 150
> +++++++++++++++++++++++++++++++++++++
> > drivers/gpu/drm/i915/gvt/gvt.h | 16 ++++
> > drivers/gpu/drm/i915/gvt/kvmgt.c | 46 ++++++++++++
> > 3 files changed, 212 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/gvt/display.c
> > b/drivers/gpu/drm/i915/gvt/display.c
> > index df1e141..a9176a1 100644
> > --- a/drivers/gpu/drm/i915/gvt/display.c
> > +++ b/drivers/gpu/drm/i915/gvt/display.c
> > @@ -442,6 +442,152 @@ void intel_gvt_emulate_vblank(struct intel_gvt
> *gvt)
> > mutex_unlock(&gvt->lock);
> > }
> >
> > +struct intel_vgpu_fb_meta_data {
> > + u32 vgpu_plane_id; /*
> vgpu_id(23:16):vgpu_pipe(15:8):vgpu_plane(7:0)*/
> > + struct intel_vgpu *vgpu; // the vGPU this meta_fb belongs to };
> > +
> > +static void meta_fb_destroy(struct drm_framebuffer *fb) {
> > + struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
> > +
> > + if (intel_fb->meta_fb.type_id != INTEL_META_FB_VGPU)
> > + return;
> > +
> > + kfree(intel_fb->meta_fb.private);
> > + intel_fb->meta_fb.private = NULL;
> > +
> > + drm_framebuffer_cleanup(fb);
> > + kfree(intel_fb);
> > +}
> > +
> > +static void clean_meta_fb(struct intel_vgpu *vgpu) {
> > + enum pipe pipe;
> > + enum plane_id plane_id;
> > + struct intel_framebuffer *intel_fb;
> > +
> > + for (pipe = 0; pipe < I915_MAX_PIPES; pipe++) {
> > + for (plane_id = 0; plane_id < I915_MAX_PLANES; plane_id++) {
> > + intel_fb = vgpu-
> >display.meta_fbs.meta_fb[pipe][plane_id];
> > + if (!intel_fb)
> > + drm_framebuffer_put(&intel_fb->base);
> > +
> > + intel_fb = NULL;
> > + }
> > + }
> > +}
> > +
> > +static int meta_fb_create_handle(struct drm_framebuffer *fb,
> > + struct drm_file *file,
> > + unsigned int *handle)
> > +{
> > + return -ENODEV;
> > +}
> > +
> > +static int meta_fb_dirty(struct drm_framebuffer *fb,
> > + struct drm_file *file,
> > + unsigned int flags,
> > + unsigned int color,
> > + struct drm_clip_rect *clips,
> > + unsigned int num_clips)
> > +{
> > + return 0;
> > +}
> > +
> > +static const struct drm_framebuffer_funcs meta_fb_funcs = {
> > + .destroy = meta_fb_destroy,
> > + .create_handle = meta_fb_create_handle,
> > + .dirty = meta_fb_dirty,
> > +};
> > +
> > +static void meta_fb_update(struct intel_framebuffer *intel_fb,
> > + enum pipe pipe, enum plane_id plane_id) {
> > + struct intel_vgpu_fb_meta_data *meta_data;
> > + struct intel_gvt *gvt;
> > +
> > + if (!intel_fb || intel_fb->meta_fb.type_id != INTEL_META_FB_VGPU)
> > + return;
> > +
> > + meta_data = intel_fb->meta_fb.private;
> > + gvt = meta_data->vgpu->gvt;
> > +
> > + if (gvt->assigned_plane[pipe][plane_id].vgpu_plane_id !=
> > + meta_data->vgpu_plane_id) {
> > + gvt->assigned_plane[pipe][plane_id].vgpu_plane_id =
> > + meta_data->vgpu_plane_id;
> > + gvt->assigned_plane[pipe][plane_id].framebuffer_id =
> > + intel_fb->base.base.id;
> > + intel_fb->meta_fb.ggtt_offset = 0;
> > + intel_fb->meta_fb.should_be_offscreen = true;
> > + } else if (!intel_fb->meta_fb.ggtt_offset) {
> > + intel_fb->meta_fb.should_be_offscreen = true;
> > + } else {
> > + intel_fb->meta_fb.should_be_offscreen = false;
> > + }
> > +}
> > +
> > +static int init_meta_fb(struct intel_vgpu *vgpu) {
> > + struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
> > + struct intel_vgpu_fb_meta_data *meta_data;
> > + struct drm_mode_fb_cmd2 mode_cmd;
> > + struct intel_framebuffer *intel_fb;
> > + enum pipe pipe;
> > + enum plane_id plane_id;
> > + int ret = 0;
> > +
> > + for (pipe = 0; pipe < I915_MAX_PIPES; pipe++) {
> > + for (plane_id = 0; plane_id < I915_MAX_PLANES; plane_id++) {
> > + intel_fb = kzalloc(sizeof(*intel_fb), GFP_KERNEL);
> > + if (!intel_fb)
> > + return -ENOMEM;
> > +
> > + /*
> > + * Create a drm_framebuffer with defaults.
> > + */
> > + mode_cmd.pixel_format = DRM_FORMAT_XRGB8888;
> > + mode_cmd.width = dev_priv-
> >drm.mode_config.max_width;
> > + mode_cmd.height = dev_priv-
> >drm.mode_config.max_height;
> > + mode_cmd.flags = DRM_MODE_FB_MODIFIERS;
> > + mode_cmd.handles[0] = 0;
> > + mode_cmd.pitches[0] = mode_cmd.width * 4;
> > + mode_cmd.offsets[0] = 0;
> > + mode_cmd.modifier[0] =
> DRM_FORMAT_MOD_LINEAR;
> > +
> > + drm_helper_mode_fill_fb_struct(&dev_priv->drm,
> > + &intel_fb->base,
> &mode_cmd);
> > +
> > + ret = drm_framebuffer_init(&dev_priv->drm,
> > + &intel_fb->base,
> &meta_fb_funcs);
> > + if (ret) {
> > + DRM_ERROR("%s: framebuffer init
> failed %d\n",
> > + __func__, ret);
> > + kfree(intel_fb);
> > + return ret;
> > + }
> > +
> > + meta_data = kmalloc(sizeof(struct
> intel_vgpu_fb_meta_data),
> > + GFP_KERNEL);
> > + if (unlikely(!meta_data)) {
> > + return -ENOMEM;
> > + }
> > +
> > + meta_data->vgpu_plane_id = (vgpu->id << 16) |
> > + (pipe << 8) | plane_id;
> > + meta_data->vgpu = vgpu;
> > +
> > + intel_fb->meta_fb.private = meta_data;
> > + intel_fb->meta_fb.update = meta_fb_update;
> > + intel_fb->meta_fb.type_id = INTEL_META_FB_VGPU;
> > +
> > + vgpu->display.meta_fbs.meta_fb[pipe][plane_id] =
> intel_fb;
> > + }
> > + }
> > + return 0;
> > +}
> > +
> > /**
> > * intel_vgpu_clean_display - clean vGPU virtual display emulation
> > * @vgpu: a vGPU
> > @@ -457,6 +603,8 @@ void intel_vgpu_clean_display(struct intel_vgpu
> *vgpu)
> > clean_virtual_dp_monitor(vgpu, PORT_D);
> > else
> > clean_virtual_dp_monitor(vgpu, PORT_B);
> > +
> > + clean_meta_fb(vgpu);
> > }
> >
> > /**
> > @@ -476,6 +624,8 @@ int intel_vgpu_init_display(struct intel_vgpu
> > *vgpu, u64 resolution)
> >
> > intel_vgpu_init_i2c_edid(vgpu);
> >
> > + init_meta_fb(vgpu);
> > +
> > if (IS_SKYLAKE(dev_priv) || IS_KABYLAKE(dev_priv))
> > return setup_virtual_dp_monitor(vgpu, PORT_D, GVT_DP_D,
> > resolution);
> > diff --git a/drivers/gpu/drm/i915/gvt/gvt.h
> > b/drivers/gpu/drm/i915/gvt/gvt.h index 31f6cdb..0ab10b0 100644
> > --- a/drivers/gpu/drm/i915/gvt/gvt.h
> > +++ b/drivers/gpu/drm/i915/gvt/gvt.h
> > @@ -131,10 +131,16 @@ struct intel_vgpu_opregion {
> >
> > #define vgpu_opregion(vgpu) (&(vgpu->opregion))
> >
> > +struct intel_vgpu_meta_fbs {
> > + struct intel_framebuffer
> *meta_fb[I915_MAX_PIPES][I915_MAX_PLANES];
> > + u32 plane_id_index;
> > +};
> > +
> > struct intel_vgpu_display {
> > struct intel_vgpu_i2c_edid i2c_edid;
> > struct intel_vgpu_port ports[I915_MAX_PORTS];
> > struct intel_vgpu_sbi sbi;
> > + struct intel_vgpu_meta_fbs meta_fbs;
> > };
> >
> > struct vgpu_sched_ctl {
> > @@ -301,6 +307,13 @@ struct intel_vgpu_type {
> > enum intel_vgpu_edid resolution;
> > };
> >
> > +struct assigned_plane {
> > + u32 vgpu_plane_id;
> > +
> > + /* userspace visible identifier */
> > + int framebuffer_id;
> > +};
> > +
> > struct intel_gvt {
> > /* GVT scope lock, protect GVT itself, and all resource currently
> > * not yet protected by special locks(vgpu and scheduler lock).
> > @@ -340,6 +353,9 @@ struct intel_gvt {
> > } engine_mmio_list;
> >
> > struct dentry *debugfs_root;
> > +
> > + /* vGPU plane assignment */
> > + struct assigned_plane
> > +assigned_plane[I915_MAX_PIPES][I915_MAX_PLANES];
> > };
> >
> > static inline struct intel_gvt *to_gvt(struct drm_i915_private *i915)
> > diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c
> > b/drivers/gpu/drm/i915/gvt/kvmgt.c
> > index c107214..7f4704d 100644
> > --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> > +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> > @@ -1420,12 +1420,58 @@ hw_id_show(struct device *dev, struct
> device_attribute *attr,
> > return sprintf(buf, "\n");
> > }
> >
> > +static ssize_t
> > +plane_id_index_show(struct device *dev, struct device_attribute *attr,
> > + char *buf)
> > +{
> > + struct mdev_device *mdev = mdev_from_dev(dev);
> > +
> > + if (mdev) {
> > + struct intel_vgpu *vgpu = (struct intel_vgpu *)
> > + mdev_get_drvdata(mdev);
> > + enum pipe pipe = vgpu->display.meta_fbs.plane_id_index &
> > + 0x000000F0;
> > + enum plane_id plane_id = vgpu-
> >display.meta_fbs.plane_id_index &
> > + 0x0000000F;
> > +
> > + if ((pipe < I915_MAX_PIPES || plane_id < I915_MAX_PLANES)
> &&
> > + vgpu->display.meta_fbs.meta_fb[pipe][plane_id]) {
> > + return sprintf(buf, "%u\n",
> > + vgpu->display.meta_fbs.meta_fb[pipe][plane_id]-
> >base.base.id);
> > + }
> > + }
> > + return sprintf(buf, "\n");
> > +}
> > +
> > +static ssize_t
> > +plane_id_index_store(struct device *dev, struct device_attribute *attr,
> > + const char *buf, size_t n)
> > +{
> > + struct mdev_device *mdev = mdev_from_dev(dev);
> > + ssize_t ret;
> > + u32 val;
> > +
> > + ret = kstrtou32(buf, 0, &val);
> > + if (ret)
> > + return ret;
> > +
> > + if (mdev) {
> > + struct intel_vgpu *vgpu = (struct intel_vgpu *)
> > + mdev_get_drvdata(mdev);
> > + vgpu->display.meta_fbs.plane_id_index = val;
> > + }
> > +
> > + return n;
> > +}
> > +
> > static DEVICE_ATTR_RO(vgpu_id);
> > static DEVICE_ATTR_RO(hw_id);
> > +static DEVICE_ATTR_RW(plane_id_index);
> >
> > static struct attribute *intel_vgpu_attrs[] = {
> > &dev_attr_vgpu_id.attr,
> > &dev_attr_hw_id.attr,
> > + &dev_attr_plane_id_index.attr,
> > NULL
> > };
> >
> > --
> > 2.7.4
> >
> > _______________________________________________
> > intel-gvt-dev mailing list
> > intel-gvt-dev at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev
>
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