diff mbox

drm: add a drm_atomic_helper_plane_check_update

Message ID 1436746892-2614-1-git-send-email-zhjwpku@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

John Hunter July 13, 2015, 12:21 a.m. UTC
From: Zhao Junwang <zhjwpku@gmail.com>

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Zhao Junwang <zhjwpku@gmail.com>
---
 drivers/gpu/drm/drm_atomic_helper.c |   55 +++++++++++++++++++++++++++++++++++
 include/drm/drm_atomic_helper.h     |    7 +++++
 2 files changed, 62 insertions(+)

Comments

Daniel Vetter July 13, 2015, 6:38 a.m. UTC | #1
On Mon, Jul 13, 2015 at 08:21:32AM +0800, John Hunter wrote:
> From: Zhao Junwang <zhjwpku@gmail.com>

A bit of text to motivate this would be good - i.e. why is this useful,
how did it blow up in the bochs conversion?

> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Signed-off-by: Zhao Junwang <zhjwpku@gmail.com>
> ---
>  drivers/gpu/drm/drm_atomic_helper.c |   55 +++++++++++++++++++++++++++++++++++
>  include/drm/drm_atomic_helper.h     |    7 +++++
>  2 files changed, 62 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
> index 536ae4d..3d94ff8 100644
> --- a/drivers/gpu/drm/drm_atomic_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_helper.c
> @@ -1336,6 +1336,61 @@ void drm_atomic_helper_swap_state(struct drm_device *dev,
>  EXPORT_SYMBOL(drm_atomic_helper_swap_state);
>  
>  /**
> + * drm_atomic_helper_plane_check_update
> + * @plane: plane object to update
> + * @state: drm plane state
> + * @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
> + * @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
> + * @can_position: is it legal to position the plane such that it
> + *                doesn't cover the entire crtc?  This will generally
> + *                only be false for primary planes.
> + * @can_update_disabled: can the plane be updated while the crtc
> + *                       is disabled?
> + *
> + * Provide a default plane check update handler

It's not a default handler since the signatures don't match. Also I think
we should mention the legacy plane helper function here too. What about

	This provides a helper to be used in a driver's plane atomic_check
	callback. It is the atomic equivalent of
	drm_plane_helper_check_update() and has the exact same semantics,
	except that it looks at the atomit CRTC state in the atomic update
	instead of legacy state directly embedded in struct &drm_crtc.

Also adding a comment to drm_plane_helper_check_update's kerneldoc would
be good, like this:

	Note: When converting over to atomic drivers you need to switch
	over to using drm_atomic_helper_plane_check_update() since only
	that correctly checks atomic state - this function here only looks
	at legacy state and hence will check against stale values in
	atomic updates.

> + *
> + * RETURNS:
> + * Zero on success, error code on failure
> + */
> +int drm_atomic_helper_plane_check_update(struct drm_plane *plane,
> +					 struct drm_plane_state *state,
> +					 int min_scale,
> +					 int max_scale,
> +					 bool can_position,
> +					 bool can_update_disabled,
> +					 bool *visible)
> +{
> +	struct drm_crtc *crtc = state->crtc;
> +	struct drm_framebuffer *fb = state->fb;
> +
> +	if (!fb)
> +		return 0;
> +
> +	struct drm_rect src = {
> +		.x1 = state->src_x,
> +		.y1 = state->src_y,
> +		.x2 = state->src_x + state->src_w,
> +		.y2 = state->src_y + state->src_h,
> +	};
> +	struct drm_rect dest = {
> +		.x1 = state->crtc_x,
> +		.y1 = state->crtc_y,
> +		.x2 = state->crtc_x + state->crtc_w,
> +		.y2 = state->crtc_y + state->crtc_h,
> +	};
> +	const struct drm_rect clip = {
> +		.x2 = crtc->mode.hdisplay,
> +		.y2 = crtc->mode.vdisplay,

crtc->mode is legacy state - we need to look at crtc_state here instead.

> +	};
> +
> +	return drm_plane_helper_check_update(plane, crtc, fb,
> +			&src, &dest, &clip,
> +			min_scale, max_scale,
> +			can_position, can_update_disabled, visible);

This looks at crtc->enabled (which is also legacy state) for
can_update_disabled. If we want to reuse this function we need to check
can_updated_disabled here and it unconditionally to true when calling the
plane helpers.

Cheers, Daniel
> +}
> +EXPORT_SYMBOL(drm_atomic_helper_plane_check_update);
> +
> +/**
>   * drm_atomic_helper_update_plane - Helper for primary plane update using atomic
>   * @plane: plane object to update
>   * @crtc: owning CRTC of owning plane
> diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h
> index cc1fee8..5305a01 100644
> --- a/include/drm/drm_atomic_helper.h
> +++ b/include/drm/drm_atomic_helper.h
> @@ -64,6 +64,13 @@ void drm_atomic_helper_swap_state(struct drm_device *dev,
>  				  struct drm_atomic_state *state);
>  
>  /* implementations for legacy interfaces */
> +int drm_atomic_helper_plane_check_update(struct drm_plane *plane,
> +					 struct drm_plane_state *state,
> +					 int min_scale,
> +					 int max_scale,
> +					 bool can_position,
> +					 bool can_update_disabled,
> +					 bool *visible);
>  int drm_atomic_helper_update_plane(struct drm_plane *plane,
>  				   struct drm_crtc *crtc,
>  				   struct drm_framebuffer *fb,
> -- 
> 1.7.10.4
> 
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
Maarten Lankhorst July 13, 2015, 7:12 a.m. UTC | #2
Op 13-07-15 om 02:21 schreef John Hunter:
> From: Zhao Junwang <zhjwpku@gmail.com>
>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Signed-off-by: Zhao Junwang <zhjwpku@gmail.com>
> ---
>  drivers/gpu/drm/drm_atomic_helper.c |   55 +++++++++++++++++++++++++++++++++++
>  include/drm/drm_atomic_helper.h     |    7 +++++
>  2 files changed, 62 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
> index 536ae4d..3d94ff8 100644
> --- a/drivers/gpu/drm/drm_atomic_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_helper.c
> @@ -1336,6 +1336,61 @@ void drm_atomic_helper_swap_state(struct drm_device *dev,
>  EXPORT_SYMBOL(drm_atomic_helper_swap_state);
>  
>  /**
> + * drm_atomic_helper_plane_check_update
> + * @plane: plane object to update
== plane_state->plane, so can be removed
> + * @state: drm plane state
rename to plane_state
> + * @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
> + * @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
> + * @can_position: is it legal to position the plane such that it
> + *                doesn't cover the entire crtc?  This will generally
> + *                only be false for primary planes.
> + * @can_update_disabled: can the plane be updated while the crtc
> + *                       is disabled?
> + *
If you look carefully at drm_plane_helper_check_update, can_update_disabled will be a noop,
so remove this parameter.

plane_state->crtc != NULL iff plane_state->fb != NULL
Maarten Lankhorst July 13, 2015, 7:17 a.m. UTC | #3
Op 13-07-15 om 09:12 schreef Maarten Lankhorst:
> Op 13-07-15 om 02:21 schreef John Hunter:
>> From: Zhao Junwang <zhjwpku@gmail.com>
>>
>> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
>> Signed-off-by: Zhao Junwang <zhjwpku@gmail.com>
>> ---
>>  drivers/gpu/drm/drm_atomic_helper.c |   55 +++++++++++++++++++++++++++++++++++
>>  include/drm/drm_atomic_helper.h     |    7 +++++
>>  2 files changed, 62 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
>> index 536ae4d..3d94ff8 100644
>> --- a/drivers/gpu/drm/drm_atomic_helper.c
>> +++ b/drivers/gpu/drm/drm_atomic_helper.c
>> @@ -1336,6 +1336,61 @@ void drm_atomic_helper_swap_state(struct drm_device *dev,
>>  EXPORT_SYMBOL(drm_atomic_helper_swap_state);
>>  
>>  /**
>> + * drm_atomic_helper_plane_check_update
>> + * @plane: plane object to update
> == plane_state->plane, so can be removed
>> + * @state: drm plane state
> rename to plane_state
>> + * @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
>> + * @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
>> + * @can_position: is it legal to position the plane such that it
>> + *                doesn't cover the entire crtc?  This will generally
>> + *                only be false for primary planes.
>> + * @can_update_disabled: can the plane be updated while the crtc
>> + *                       is disabled?
>> + *
> If you look carefully at drm_plane_helper_check_update, can_update_disabled will be a noop,
> so remove this parameter.
>
> plane_state->crtc != NULL iff plane_state->fb != NULL
>
Oops, should check harder before I hit send. You can disable a crtc with planes attached, but the clip
will be bogus in that case. When !crtc->enable the clip will be set { 0, 0, 0, 0 }, hiding the plane.

There's still no need for can_update_disabled in the atomic world though, the plane state will be properly recalculated during a modeset.
If you don't want to update a plane while a crtc is disabled, just don't update it in your commit function.
John Hunter July 13, 2015, 7:35 a.m. UTC | #4
So we should remove the can_update_disabled parameter, and set it to true
in the drm_plane_helper_check_update callback?

I am still learning the atomic world, pls forgive if I don't understand it
well

On Mon, Jul 13, 2015 at 3:17 PM, Maarten Lankhorst <
maarten.lankhorst@linux.intel.com> wrote:

> Op 13-07-15 om 09:12 schreef Maarten Lankhorst:
> > Op 13-07-15 om 02:21 schreef John Hunter:
> >> From: Zhao Junwang <zhjwpku@gmail.com>
> >>
> >> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> >> Signed-off-by: Zhao Junwang <zhjwpku@gmail.com>
> >> ---
> >>  drivers/gpu/drm/drm_atomic_helper.c |   55
> +++++++++++++++++++++++++++++++++++
> >>  include/drm/drm_atomic_helper.h     |    7 +++++
> >>  2 files changed, 62 insertions(+)
> >>
> >> diff --git a/drivers/gpu/drm/drm_atomic_helper.c
> b/drivers/gpu/drm/drm_atomic_helper.c
> >> index 536ae4d..3d94ff8 100644
> >> --- a/drivers/gpu/drm/drm_atomic_helper.c
> >> +++ b/drivers/gpu/drm/drm_atomic_helper.c
> >> @@ -1336,6 +1336,61 @@ void drm_atomic_helper_swap_state(struct
> drm_device *dev,
> >>  EXPORT_SYMBOL(drm_atomic_helper_swap_state);
> >>
> >>  /**
> >> + * drm_atomic_helper_plane_check_update
> >> + * @plane: plane object to update
> > == plane_state->plane, so can be removed
> >> + * @state: drm plane state
> > rename to plane_state
> >> + * @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
> >> + * @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
> >> + * @can_position: is it legal to position the plane such that it
> >> + *                doesn't cover the entire crtc?  This will generally
> >> + *                only be false for primary planes.
> >> + * @can_update_disabled: can the plane be updated while the crtc
> >> + *                       is disabled?
> >> + *
> > If you look carefully at drm_plane_helper_check_update,
> can_update_disabled will be a noop,
> > so remove this parameter.
> >
> > plane_state->crtc != NULL iff plane_state->fb != NULL
> >
> Oops, should check harder before I hit send. You can disable a crtc with
> planes attached, but the clip
> will be bogus in that case. When !crtc->enable the clip will be set { 0,
> 0, 0, 0 }, hiding the plane.
>
> There's still no need for can_update_disabled in the atomic world though,
> the plane state will be properly recalculated during a modeset.
> If you don't want to update a plane while a crtc is disabled, just don't
> update it in your commit function.
>
diff mbox

Patch

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 536ae4d..3d94ff8 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1336,6 +1336,61 @@  void drm_atomic_helper_swap_state(struct drm_device *dev,
 EXPORT_SYMBOL(drm_atomic_helper_swap_state);
 
 /**
+ * drm_atomic_helper_plane_check_update
+ * @plane: plane object to update
+ * @state: drm plane state
+ * @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
+ * @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
+ * @can_position: is it legal to position the plane such that it
+ *                doesn't cover the entire crtc?  This will generally
+ *                only be false for primary planes.
+ * @can_update_disabled: can the plane be updated while the crtc
+ *                       is disabled?
+ *
+ * Provide a default plane check update handler
+ *
+ * RETURNS:
+ * Zero on success, error code on failure
+ */
+int drm_atomic_helper_plane_check_update(struct drm_plane *plane,
+					 struct drm_plane_state *state,
+					 int min_scale,
+					 int max_scale,
+					 bool can_position,
+					 bool can_update_disabled,
+					 bool *visible)
+{
+	struct drm_crtc *crtc = state->crtc;
+	struct drm_framebuffer *fb = state->fb;
+
+	if (!fb)
+		return 0;
+
+	struct drm_rect src = {
+		.x1 = state->src_x,
+		.y1 = state->src_y,
+		.x2 = state->src_x + state->src_w,
+		.y2 = state->src_y + state->src_h,
+	};
+	struct drm_rect dest = {
+		.x1 = state->crtc_x,
+		.y1 = state->crtc_y,
+		.x2 = state->crtc_x + state->crtc_w,
+		.y2 = state->crtc_y + state->crtc_h,
+	};
+	const struct drm_rect clip = {
+		.x2 = crtc->mode.hdisplay,
+		.y2 = crtc->mode.vdisplay,
+	};
+
+	return drm_plane_helper_check_update(plane, crtc, fb,
+			&src, &dest, &clip,
+			min_scale, max_scale,
+			can_position, can_update_disabled, visible);
+}
+EXPORT_SYMBOL(drm_atomic_helper_plane_check_update);
+
+/**
  * drm_atomic_helper_update_plane - Helper for primary plane update using atomic
  * @plane: plane object to update
  * @crtc: owning CRTC of owning plane
diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h
index cc1fee8..5305a01 100644
--- a/include/drm/drm_atomic_helper.h
+++ b/include/drm/drm_atomic_helper.h
@@ -64,6 +64,13 @@  void drm_atomic_helper_swap_state(struct drm_device *dev,
 				  struct drm_atomic_state *state);
 
 /* implementations for legacy interfaces */
+int drm_atomic_helper_plane_check_update(struct drm_plane *plane,
+					 struct drm_plane_state *state,
+					 int min_scale,
+					 int max_scale,
+					 bool can_position,
+					 bool can_update_disabled,
+					 bool *visible);
 int drm_atomic_helper_update_plane(struct drm_plane *plane,
 				   struct drm_crtc *crtc,
 				   struct drm_framebuffer *fb,