Re: [PATCH v2] drm/meson: Fix atomic mode switching regression

[Neil Armstrong]

On 15/01/2019 13:06, Daniel Vetter wrote:
> On Mon, Jan 14, 2019 at 04:31:18PM +0100, Neil Armstrong wrote:
>> Since commit 2bcd3ecab773 when switching mode from X11 (ubuntu mate for
>> example) the display gets blurry, looking like an invalid framebuffer width.
>>
>> This commit fixed atomic crtc modesetting in a totally wrong way and
>> introduced a local unnecessary ->enabled crtc state.
>>
>> This commit reverts the crctc _begin() and _enable() changes and simply
>> adds drm_atomic_helper_commit_tail_rpm as helper.
>>
>> Reported-by: Tony McKahan <tonymckahan@xxxxxxxxx>
>> Suggested-by: Daniel Vetter <daniel@xxxxxxxx>
>> Fixes: 2bcd3ecab773 ("drm/meson: Fixes for drm_crtc_vblank_on/off support")
>> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> 
> For the record (I already acked this on irc):

Thanks, I got it, I was checking against the known regression to see if it doesn't
add a new one !

> 
> Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx>

Applied to drm-misc-fixes

Neil

>> ---
>>  drivers/gpu/drm/meson/meson_crtc.c | 23 ++---------------------
>>  drivers/gpu/drm/meson/meson_drv.c  |  6 ++++++
>>  2 files changed, 8 insertions(+), 21 deletions(-)
>>
>> Changes since v1:
>> - drop the unecessary local ->enabled logic
>> - use drm_atomic_helper_commit_tail_rpm as atomic_commit_tail helper
>>
>> diff --git a/drivers/gpu/drm/meson/meson_crtc.c b/drivers/gpu/drm/meson/meson_crtc.c
>> index 75d97f1b2e8f..4f5c67f70c4d 100644
>> --- a/drivers/gpu/drm/meson/meson_crtc.c
>> +++ b/drivers/gpu/drm/meson/meson_crtc.c
>> @@ -46,7 +46,6 @@ struct meson_crtc {
>>  	struct drm_crtc base;
>>  	struct drm_pending_vblank_event *event;
>>  	struct meson_drm *priv;
>> -	bool enabled;
>>  };
>>  #define to_meson_crtc(x) container_of(x, struct meson_crtc, base)
>>  
>> @@ -82,7 +81,8 @@ static const struct drm_crtc_funcs meson_crtc_funcs = {
>>  
>>  };
>>  
>> -static void meson_crtc_enable(struct drm_crtc *crtc)
>> +static void meson_crtc_atomic_enable(struct drm_crtc *crtc,
>> +				     struct drm_crtc_state *old_state)
>>  {
>>  	struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
>>  	struct drm_crtc_state *crtc_state = crtc->state;
>> @@ -108,20 +108,6 @@ static void meson_crtc_enable(struct drm_crtc *crtc)
>>  
>>  	drm_crtc_vblank_on(crtc);
>>  
>> -	meson_crtc->enabled = true;
>> -}
>> -
>> -static void meson_crtc_atomic_enable(struct drm_crtc *crtc,
>> -				     struct drm_crtc_state *old_state)
>> -{
>> -	struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
>> -	struct meson_drm *priv = meson_crtc->priv;
>> -
>> -	DRM_DEBUG_DRIVER("\n");
>> -
>> -	if (!meson_crtc->enabled)
>> -		meson_crtc_enable(crtc);
>> -
>>  	priv->viu.osd1_enabled = true;
>>  }
>>  
>> @@ -153,8 +139,6 @@ static void meson_crtc_atomic_disable(struct drm_crtc *crtc,
>>  
>>  		crtc->state->event = NULL;
>>  	}
>> -
>> -	meson_crtc->enabled = false;
>>  }
>>  
>>  static void meson_crtc_atomic_begin(struct drm_crtc *crtc,
>> @@ -163,9 +147,6 @@ static void meson_crtc_atomic_begin(struct drm_crtc *crtc,
>>  	struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
>>  	unsigned long flags;
>>  
>> -	if (crtc->state->enable && !meson_crtc->enabled)
>> -		meson_crtc_enable(crtc);
>> -
>>  	if (crtc->state->event) {
>>  		WARN_ON(drm_crtc_vblank_get(crtc) != 0);
>>  
>> diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c
>> index 3ee4d4a4ecba..a74d861ddceb 100644
>> --- a/drivers/gpu/drm/meson/meson_drv.c
>> +++ b/drivers/gpu/drm/meson/meson_drv.c
>> @@ -75,6 +75,11 @@ static const struct drm_mode_config_funcs meson_mode_config_funcs = {
>>  	.fb_create           = drm_gem_fb_create,
>>  };
>>  
>> +
>> +static const struct drm_mode_config_helper_funcs meson_mode_config_helpers = {
>> +	.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
>> +};
>> +
>>  static irqreturn_t meson_irq(int irq, void *arg)
>>  {
>>  	struct drm_device *dev = arg;
>> @@ -266,6 +271,7 @@ static int meson_drv_bind_master(struct device *dev, bool has_components)
>>  	drm->mode_config.max_width = 3840;
>>  	drm->mode_config.max_height = 2160;
>>  	drm->mode_config.funcs = &meson_mode_config_funcs;
>> +	drm->mode_config.helper_private	= &meson_mode_config_helpers;
>>  
>>  	/* Hardware Initialization */
>>  
>> -- 
>> 2.20.1
>>
>