Re: [PATCH] drm/exynos: switch to universal plane API

[Andrzej Hajda <a.hajda@samsung.com>]

On 09/19/2014 03:02 AM, Joonyoung Shim wrote:
> Hi Andrzej,
>
> On 09/18/2014 10:17 PM, Andrzej Hajda wrote:
>> The patch replaces legacy functions
>> drm_plane_init() / drm_crtc_init() with
>> drm_universal_plane_init() and drm_crtc_init_with_planes().
>> It allows to replace fake primary plane with the real one.
>>
>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>> ---
>> Hi Inki,
>>
>> I have tested this patch with trats board, it looks OK.
>> As a side effect it should solve fb refcounting issues
>> reported by me and Daniel Drake.
>>
>> Regards
>> Andrzej
>> ---
>>  drivers/gpu/drm/exynos/exynos_drm_crtc.c  | 63 ++++++++++++++++---------------
>>  drivers/gpu/drm/exynos/exynos_drm_drv.c   |  5 ++-
>>  drivers/gpu/drm/exynos/exynos_drm_plane.c | 17 +++++----
>>  drivers/gpu/drm/exynos/exynos_drm_plane.h |  3 +-
>>  4 files changed, 47 insertions(+), 41 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
>> index b68e58f..d2f713e 100644
>> --- a/drivers/gpu/drm/exynos/exynos_drm_crtc.c
>> +++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
>> @@ -32,7 +32,6 @@ enum exynos_crtc_mode {
>>   * Exynos specific crtc structure.
>>   *
>>   * @drm_crtc: crtc object.
>> - * @drm_plane: pointer of private plane object for this crtc
>>   * @manager: the manager associated with this crtc
>>   * @pipe: a crtc index created at load() with a new crtc object creation
>>   *	and the crtc object would be set to private->crtc array
>> @@ -46,7 +45,6 @@ enum exynos_crtc_mode {
>>   */
>>  struct exynos_drm_crtc {
>>  	struct drm_crtc			drm_crtc;
>> -	struct drm_plane		*plane;
>>  	struct exynos_drm_manager	*manager;
>>  	unsigned int			pipe;
>>  	unsigned int			dpms;
>> @@ -94,12 +92,12 @@ static void exynos_drm_crtc_commit(struct drm_crtc *crtc)
>>  
>>  	exynos_drm_crtc_dpms(crtc, DRM_MODE_DPMS_ON);
>>  
>> -	exynos_plane_commit(exynos_crtc->plane);
>> +	exynos_plane_commit(crtc->primary);
>>  
>>  	if (manager->ops->commit)
>>  		manager->ops->commit(manager);
>>  
>> -	exynos_plane_dpms(exynos_crtc->plane, DRM_MODE_DPMS_ON);
>> +	exynos_plane_dpms(crtc->primary, DRM_MODE_DPMS_ON);
>>  }
>>  
>>  static bool
>> @@ -123,10 +121,9 @@ exynos_drm_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
>>  {
>>  	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
>>  	struct exynos_drm_manager *manager = exynos_crtc->manager;
>> -	struct drm_plane *plane = exynos_crtc->plane;
>> +	struct drm_framebuffer *fb = crtc->primary->fb;
>>  	unsigned int crtc_w;
>>  	unsigned int crtc_h;
>> -	int ret;
>>  
>>  	/*
>>  	 * copy the mode data adjusted by mode_fixup() into crtc->mode
>> @@ -134,29 +131,21 @@ exynos_drm_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
>>  	 */
>>  	memcpy(&crtc->mode, adjusted_mode, sizeof(*adjusted_mode));
>>  
>> -	crtc_w = crtc->primary->fb->width - x;
>> -	crtc_h = crtc->primary->fb->height - y;
>> +	crtc_w = fb->width - x;
>> +	crtc_h = fb->height - y;
>>  
>>  	if (manager->ops->mode_set)
>>  		manager->ops->mode_set(manager, &crtc->mode);
>>  
>> -	ret = exynos_plane_mode_set(plane, crtc, crtc->primary->fb, 0, 0, crtc_w, crtc_h,
>> -				    x, y, crtc_w, crtc_h);
>> -	if (ret)
>> -		return ret;
>> -
>> -	plane->crtc = crtc;
>> -	plane->fb = crtc->primary->fb;
>> -	drm_framebuffer_reference(plane->fb);
>> -
>> -	return 0;
>> +	return exynos_plane_mode_set(crtc->primary, crtc, fb, 0, 0,
>> +				     crtc_w, crtc_h, x, y, crtc_w, crtc_h);
>>  }
>>  
>>  static int exynos_drm_crtc_mode_set_commit(struct drm_crtc *crtc, int x, int y,
>>  					  struct drm_framebuffer *old_fb)
>>  {
>>  	struct exynos_drm_crtc *exynos_crtc = to_exynos_crtc(crtc);
>> -	struct drm_plane *plane = exynos_crtc->plane;
>> +	struct drm_framebuffer *fb = crtc->primary->fb;
>>  	unsigned int crtc_w;
>>  	unsigned int crtc_h;
>>  	int ret;
>> @@ -167,11 +156,11 @@ static int exynos_drm_crtc_mode_set_commit(struct drm_crtc *crtc, int x, int y,
>>  		return -EPERM;
>>  	}
>>  
>> -	crtc_w = crtc->primary->fb->width - x;
>> -	crtc_h = crtc->primary->fb->height - y;
>> +	crtc_w = fb->width - x;
>> +	crtc_h = fb->height - y;
>>  
>> -	ret = exynos_plane_mode_set(plane, crtc, crtc->primary->fb, 0, 0, crtc_w, crtc_h,
>> -				    x, y, crtc_w, crtc_h);
>> +	ret = exynos_plane_mode_set(crtc->primary, crtc, fb, 0, 0,
>> +				    crtc_w, crtc_h, x, y, crtc_w, crtc_h);
>>  	if (ret)
>>  		return ret;
>>  
>> @@ -279,6 +268,7 @@ static void exynos_drm_crtc_destroy(struct drm_crtc *crtc)
>>  
>>  	private->crtc[exynos_crtc->pipe] = NULL;
>>  
>> +	crtc->primary->funcs->destroy(crtc->primary);
> This is unnecessary.

The question is how these object should be destroyed. In current code
crtc is destroyed in fimd_unbind and it is called before
drm_mode_config_cleanup
which destroys all planes.
In such case primary plane will stay with .crtc pointing to non-existing
crtc.
Maybe performing crtcs cleanup after planes cleanup is better solution???

>
>>  	drm_crtc_cleanup(crtc);
>>  	kfree(exynos_crtc);
>>  }
>> @@ -304,8 +294,7 @@ static int exynos_drm_crtc_set_property(struct drm_crtc *crtc,
>>  			exynos_drm_crtc_commit(crtc);
>>  			break;
>>  		case CRTC_MODE_BLANK:
>> -			exynos_plane_dpms(exynos_crtc->plane,
>> -					  DRM_MODE_DPMS_OFF);
>> +			exynos_plane_dpms(crtc->primary, DRM_MODE_DPMS_OFF);
>>  			break;
>>  		default:
>>  			break;
>> @@ -351,8 +340,10 @@ static void exynos_drm_crtc_attach_mode_property(struct drm_crtc *crtc)
>>  int exynos_drm_crtc_create(struct exynos_drm_manager *manager)
>>  {
>>  	struct exynos_drm_crtc *exynos_crtc;
>> +	struct drm_plane *plane;
>>  	struct exynos_drm_private *private = manager->drm_dev->dev_private;
>>  	struct drm_crtc *crtc;
>> +	int ret;
>>  
>>  	exynos_crtc = kzalloc(sizeof(*exynos_crtc), GFP_KERNEL);
>>  	if (!exynos_crtc)
>> @@ -364,11 +355,11 @@ int exynos_drm_crtc_create(struct exynos_drm_manager *manager)
>>  	exynos_crtc->dpms = DRM_MODE_DPMS_OFF;
>>  	exynos_crtc->manager = manager;
>>  	exynos_crtc->pipe = manager->pipe;
>> -	exynos_crtc->plane = exynos_plane_init(manager->drm_dev,
>> -				1 << manager->pipe, true);
>> -	if (!exynos_crtc->plane) {
>> -		kfree(exynos_crtc);
>> -		return -ENOMEM;
>> +	plane = exynos_plane_init(manager->drm_dev, 1 << manager->pipe,
>> +				  DRM_PLANE_TYPE_PRIMARY);
>> +	if (IS_ERR(plane)) {
>> +		ret = PTR_ERR(plane);
>> +		goto err_plane;
>>  	}
>>  
>>  	manager->crtc = &exynos_crtc->drm_crtc;
>> @@ -376,12 +367,22 @@ int exynos_drm_crtc_create(struct exynos_drm_manager *manager)
>>  
>>  	private->crtc[manager->pipe] = crtc;
>>  
>> -	drm_crtc_init(manager->drm_dev, crtc, &exynos_crtc_funcs);
>> +	ret = drm_crtc_init_with_planes(manager->drm_dev, crtc, plane, NULL,
>> +					&exynos_crtc_funcs);
>> +	if (ret < 0)
>> +		goto err_crtc;
>> +
>>  	drm_crtc_helper_add(crtc, &exynos_crtc_helper_funcs);
>>  
>>  	exynos_drm_crtc_attach_mode_property(crtc);
>>  
>>  	return 0;
>> +
>> +err_crtc:
>> +	plane->funcs->destroy(plane);
>> +err_plane:
>> +	kfree(exynos_crtc);
>> +	return ret;
>>  }
>>  
>>  int exynos_drm_crtc_enable_vblank(struct drm_device *dev, int pipe)
>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c
>> index 9b00e4e..a439452 100644
>> --- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
>> +++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
>> @@ -86,8 +86,9 @@ static int exynos_drm_load(struct drm_device *dev, unsigned long flags)
>>  		struct drm_plane *plane;
>>  		unsigned long possible_crtcs = (1 << MAX_CRTC) - 1;
>>  
>> -		plane = exynos_plane_init(dev, possible_crtcs, false);
>> -		if (!plane)
>> +		plane = exynos_plane_init(dev, possible_crtcs,
>> +					  DRM_PLANE_TYPE_OVERLAY);
>> +		if (IS_ERR(plane))
>>  			goto err_mode_config_cleanup;
>>  	}
>>  
>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_plane.c b/drivers/gpu/drm/exynos/exynos_drm_plane.c
>> index 8371cbd..15e37a0 100644
>> --- a/drivers/gpu/drm/exynos/exynos_drm_plane.c
>> +++ b/drivers/gpu/drm/exynos/exynos_drm_plane.c
>> @@ -139,6 +139,8 @@ int exynos_plane_mode_set(struct drm_plane *plane, struct drm_crtc *crtc,
>>  			overlay->crtc_x, overlay->crtc_y,
>>  			overlay->crtc_width, overlay->crtc_height);
>>  
>> +	plane->crtc = crtc;
>> +
> OK, then we can remove same code from exynos_update_plane().

Right.

>
> One more, plane->crtc is NULL before mode_set or setplane so it's
> problem if call plane->funcs->destroy with plane->crtc == NULL.
> We need checking plane->crtc is NULL in exynos_disable_plane().

I can simply add checks, but why we allow the plane with NULL crtc to be
enabled?

Regards
Andrzej

>
>>  	exynos_drm_crtc_plane_mode_set(crtc, overlay);
>>  
>>  	return 0;
>> @@ -254,25 +256,26 @@ static void exynos_plane_attach_zpos_property(struct drm_plane *plane)
>>  }
>>  
>>  struct drm_plane *exynos_plane_init(struct drm_device *dev,
>> -				    unsigned long possible_crtcs, bool priv)
>> +				    unsigned long possible_crtcs,
>> +				    enum drm_plane_type type)
>>  {
>>  	struct exynos_plane *exynos_plane;
>>  	int err;
>>  
>>  	exynos_plane = kzalloc(sizeof(struct exynos_plane), GFP_KERNEL);
>>  	if (!exynos_plane)
>> -		return NULL;
>> +		return ERR_PTR(-ENOMEM);
>>  
>> -	err = drm_plane_init(dev, &exynos_plane->base, possible_crtcs,
>> -			      &exynos_plane_funcs, formats, ARRAY_SIZE(formats),
>> -			      priv);
>> +	err = drm_universal_plane_init(dev, &exynos_plane->base, possible_crtcs,
>> +				       &exynos_plane_funcs, formats,
>> +				       ARRAY_SIZE(formats), type);
>>  	if (err) {
>>  		DRM_ERROR("failed to initialize plane\n");
>>  		kfree(exynos_plane);
>> -		return NULL;
>> +		return ERR_PTR(err);
>>  	}
>>  
>> -	if (priv)
>> +	if (type == DRM_PLANE_TYPE_PRIMARY)
>>  		exynos_plane->overlay.zpos = DEFAULT_ZPOS;
>>  	else
>>  		exynos_plane_attach_zpos_property(&exynos_plane->base);
>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_plane.h b/drivers/gpu/drm/exynos/exynos_drm_plane.h
>> index 84d464c..0d1986b 100644
>> --- a/drivers/gpu/drm/exynos/exynos_drm_plane.h
>> +++ b/drivers/gpu/drm/exynos/exynos_drm_plane.h
>> @@ -17,4 +17,5 @@ int exynos_plane_mode_set(struct drm_plane *plane, struct drm_crtc *crtc,
>>  void exynos_plane_commit(struct drm_plane *plane);
>>  void exynos_plane_dpms(struct drm_plane *plane, int mode);
>>  struct drm_plane *exynos_plane_init(struct drm_device *dev,
>> -				    unsigned long possible_crtcs, bool priv);
>> +				    unsigned long possible_crtcs,
>> +				    enum drm_plane_type type);
>>
> Thanks.
>