[PATCH] drm/vkms: Add vblank events simulated by hrtimers

Ville Syrjälä ville.syrjala at linux.intel.com
Mon Jun 25 17:49:55 UTC 2018


On Mon, Jun 25, 2018 at 02:19:22PM -0300, Rodrigo Siqueira wrote:
> This commit adds regular vblank events simulated through hrtimers, which
> is a feature required by VKMS to mimic real hardware. In this sense,
> this commit adopts a default frequency of 60Hz for vblank interval.
> Finally, this commit implements handlers for some of the atomic and
> vblank hooks.
> 
> Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo at gmail.com>
> ---
> Note:
> 	- This patch depends on the patchset "drm/vkms: Updates to meet basic
> 		kms_flip requirements"
> 		link: https://lists.freedesktop.org/archives/dri-devel/2018-June/180823.html
> 
>  drivers/gpu/drm/vkms/vkms_crtc.c | 90 +++++++++++++++++++++++++++++++-
>  drivers/gpu/drm/vkms/vkms_drv.c  |  6 +++
>  drivers/gpu/drm/vkms/vkms_drv.h  |  9 ++++
>  3 files changed, 103 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
> index 84cc05506b09..73aae129c37d 100644
> --- a/drivers/gpu/drm/vkms/vkms_crtc.c
> +++ b/drivers/gpu/drm/vkms/vkms_crtc.c
> @@ -10,6 +10,52 @@
>  #include <drm/drm_atomic_helper.h>
>  #include <drm/drm_crtc_helper.h>
>  
> +static enum hrtimer_restart vkms_vblank_simulate(struct hrtimer *timer)
> +{
> +	struct vkms_output *output = container_of(timer, struct vkms_output,
> +						  vblank_hrtimer);
> +	struct drm_crtc *crtc = &output->crtc;
> +	unsigned long flags;
> +	int ret_overrun;
> +	bool ret;
> +
> +	ret = drm_crtc_handle_vblank(&output->crtc);
> +	if (!ret)
> +		DRM_ERROR("vkms failure on handling vblank");
> +
> +	spin_lock_irqsave(&crtc->dev->event_lock, flags);
> +	if (output->event) {
> +		drm_crtc_send_vblank_event(crtc, output->event);
> +		drm_crtc_vblank_put(crtc);
> +		output->event = NULL;
> +	}
> +	spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
> +
> +	ret_overrun = hrtimer_forward_now(&output->vblank_hrtimer,
> +					  output->period_ns);
> +
> +	return HRTIMER_RESTART;
> +}
> +
> +static int vkms_enable_vblank(struct drm_crtc *crtc)
> +{
> +	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
> +
> +	hrtimer_init(&out->vblank_hrtimer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
> +	out->vblank_hrtimer.function = &vkms_vblank_simulate;
> +	out->period_ns = ktime_set(0, DEFAULT_VBLANK_NS);

Don't you want the vblank interval to roughly match the crtc timings the
user asked for?

> +	hrtimer_start(&out->vblank_hrtimer, out->period_ns, HRTIMER_MODE_ABS);
> +
> +	return 0;
> +}
> +
> +static void vkms_disable_vblank(struct drm_crtc *crtc)
> +{
> +	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
> +
> +	hrtimer_cancel(&out->vblank_hrtimer);
> +}
> +
>  static const struct drm_crtc_funcs vkms_crtc_funcs = {
>  	.set_config             = drm_atomic_helper_set_config,
>  	.destroy                = drm_crtc_cleanup,
> @@ -17,6 +63,8 @@ static const struct drm_crtc_funcs vkms_crtc_funcs = {
>  	.reset                  = drm_atomic_helper_crtc_reset,
>  	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
>  	.atomic_destroy_state   = drm_atomic_helper_crtc_destroy_state,
> +	.enable_vblank		= vkms_enable_vblank,
> +	.disable_vblank		= vkms_disable_vblank,
>  };
>  
>  static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
> @@ -27,12 +75,50 @@ static int vkms_crtc_atomic_check(struct drm_crtc *crtc,
>  
>  static void vkms_crtc_atomic_enable(struct drm_crtc *crtc,
>  				    struct drm_crtc_state *old_state)
> +{
> +	drm_crtc_vblank_on(crtc);
> +}
> +
> +static void vkms_crtc_atomic_begin(struct drm_crtc *crtc,
> +				   struct drm_crtc_state *old_s)
> +{
> +	struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
> +
> +	if (crtc->state->event) {
> +		crtc->state->event->pipe = drm_crtc_index(crtc);
> +		WARN_ON(drm_crtc_vblank_get(crtc) != 0);
> +
> +		vkms_output->event = crtc->state->event;
> +		crtc->state->event = NULL;
> +	}
> +}
> +
> +static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
> +				   struct drm_crtc_state *old_crtc_state)
> +{
> +	struct drm_pending_vblank_event *event = crtc->state->event;
> +
> +	if (!event)
> +		return;
> +
> +	crtc->state->event = NULL;
> +
> +	spin_lock_irq(&crtc->dev->event_lock);
> +	if (drm_crtc_vblank_get(crtc))
> +		drm_crtc_send_vblank_event(crtc, event);
> +	spin_unlock_irq(&crtc->dev->event_lock);
> +}
> +
> +static void vkms_crtc_commit(struct drm_crtc *crtc)
>  {
>  }
>  
>  static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = {
> -	.atomic_check  = vkms_crtc_atomic_check,
> -	.atomic_enable = vkms_crtc_atomic_enable,
> +	.atomic_check	= vkms_crtc_atomic_check,
> +	.atomic_enable	= vkms_crtc_atomic_enable,
> +	.atomic_flush	= vkms_crtc_atomic_flush,
> +	.atomic_begin	= vkms_crtc_atomic_begin,
> +	.commit		= vkms_crtc_commit,
>  };
>  
>  int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
> diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c
> index fe93f8c17997..c56d66d9ec56 100644
> --- a/drivers/gpu/drm/vkms/vkms_drv.c
> +++ b/drivers/gpu/drm/vkms/vkms_drv.c
> @@ -102,6 +102,12 @@ static int __init vkms_init(void)
>  		goto out_fini;
>  	}
>  
> +	ret = drm_vblank_init(&vkms_device->drm, 1);
> +	if (ret) {
> +		DRM_ERROR("Failed to vblank\n");
> +		goto out_fini;
> +	}
> +
>  	ret = vkms_modeset_init(vkms_device);
>  	if (ret)
>  		goto out_unregister;
> diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
> index 76f1720f81a5..f115e7d1ae03 100644
> --- a/drivers/gpu/drm/vkms/vkms_drv.h
> +++ b/drivers/gpu/drm/vkms/vkms_drv.h
> @@ -5,6 +5,7 @@
>  #include <drm/drm.h>
>  #include <drm/drm_gem.h>
>  #include <drm/drm_encoder.h>
> +#include <linux/hrtimer.h>
>  
>  #define XRES_MIN    32
>  #define YRES_MIN    32
> @@ -15,6 +16,8 @@
>  #define XRES_MAX  8192
>  #define YRES_MAX  8192
>  
> +#define DEFAULT_VBLANK_NS 16666666
> +
>  static const u32 vkms_formats[] = {
>  	DRM_FORMAT_XRGB8888,
>  };
> @@ -23,6 +26,9 @@ struct vkms_output {
>  	struct drm_crtc crtc;
>  	struct drm_encoder encoder;
>  	struct drm_connector connector;
> +	struct hrtimer vblank_hrtimer;
> +	ktime_t period_ns;
> +	struct drm_pending_vblank_event *event;
>  };
>  
>  struct vkms_device {
> @@ -37,6 +43,9 @@ struct vkms_gem_object {
>  	struct page **pages;
>  };
>  
> +#define drm_crtc_to_vkms_output(target) \
> +	container_of(target, struct vkms_output, crtc)
> +
>  int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc,
>  		   struct drm_plane *primary, struct drm_plane *cursor);
>  
> -- 
> 2.17.1
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Ville Syrjälä
Intel


More information about the dri-devel mailing list