[RFC,v4,6/7] drm/msm/dpu: Allow NULL FBs in atomic commit

Since solid fill planes allow for a NULL framebuffer in a valid commit,
add NULL framebuffer checks to atomic commit calls within DPU.

Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c  |  9 ++++++-
 drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 45 +++++++++++++++++++------------
 2 files changed, 36 insertions(+), 18 deletions(-)

On 6/30/2023 1:21 AM, Pekka Paalanen wrote:
> On Fri, 30 Jun 2023 03:52:37 +0300
> Dmitry Baryshkov <dmitry.baryshkov@linaro.org> wrote:
> 
>> On 30/06/2023 03:25, Jessica Zhang wrote:
>>> Since solid fill planes allow for a NULL framebuffer in a valid commit,
>>> add NULL framebuffer checks to atomic commit calls within DPU.
>>>
>>> Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com>
>>> ---
>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c  |  9 ++++++-
>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 45 +++++++++++++++++++------------
>>>    2 files changed, 36 insertions(+), 18 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
>>> index 1edf2b6b0a26..d1b37d2cc202 100644
>>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
>>> @@ -451,6 +451,7 @@ static void _dpu_crtc_blend_setup_mixer(struct drm_crtc *crtc,
>>>    	struct drm_plane_state *state;
>>>    	struct dpu_crtc_state *cstate = to_dpu_crtc_state(crtc->state);
>>>    	struct dpu_plane_state *pstate = NULL;
>>> +	const struct msm_format *fmt;
>>>    	struct dpu_format *format;
>>>    	struct dpu_hw_ctl *ctl = mixer->lm_ctl;
>>>    
>>> @@ -470,7 +471,13 @@ static void _dpu_crtc_blend_setup_mixer(struct drm_crtc *crtc,
>>>    		pstate = to_dpu_plane_state(state);
>>>    		fb = state->fb;
>>>    
>>> -		format = to_dpu_format(msm_framebuffer_format(pstate->base.fb));
>>> +		if (state->pixel_source == DRM_PLANE_PIXEL_SOURCE_FB && fb)
>>> +			fmt = msm_framebuffer_format(pstate->base.fb);
>>> +		else
>>> +			fmt = dpu_get_msm_format(&_dpu_crtc_get_kms(crtc)->base,
>>> +					DRM_FORMAT_RGBA8888, 0);
>>
>> The DRM_FORMAT_RGBA8888 should be defined somewhere in patch 1 as format
>> for the solid_fill, then that define can be used in this patch.
> 
> Isn't this just a driver-specific decision to convert a RGB323232
> solid_fill to be presented as a RGBA8888?

Hi Dmitry and Pekka,

Yes, the ABGR8888 format is specific to msm/dpu. In earlier revisions of 
the series, we had come to an agreement that the solid fill property 
should take RGB323232 to match the similar Wayland single pixel buffer 
protocol [1].

[1] 
https://gitlab.freedesktop.org/wayland/wayland-protocols/-/merge_requests/104

> 
> Though, below there is ABGR8888 used for something... inconsistent?

Typo on my part. The format should be consistently ABGR8888.

Thanks,

Jessica Zhang

> 
> 
> Thanks,
> pq
> 
>>
>>> +
>>> +		format = to_dpu_format(fmt);
>>>    
>>>    		if (pstate->stage == DPU_STAGE_BASE && format->alpha_enable)
>>>    			bg_alpha_enable = true;
>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
>>> index 5f0984ce62b1..4476722f03bb 100644
>>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
>>> @@ -837,8 +837,10 @@ static int dpu_plane_atomic_check(struct drm_plane *plane,
>>>    
>>>    	pipe_cfg->dst_rect = new_plane_state->dst;
>>>    
>>> -	fb_rect.x2 = new_plane_state->fb->width;
>>> -	fb_rect.y2 = new_plane_state->fb->height;
>>> +	if (new_plane_state->pixel_source == DRM_PLANE_PIXEL_SOURCE_FB && new_plane_state->fb) {
>>> +		fb_rect.x2 = new_plane_state->fb->width;
>>> +		fb_rect.y2 = new_plane_state->fb->height;
>>> +	}
>>>    
>>>    	/* Ensure fb size is supported */
>>>    	if (drm_rect_width(&fb_rect) > MAX_IMG_WIDTH ||
>>> @@ -848,10 +850,13 @@ static int dpu_plane_atomic_check(struct drm_plane *plane,
>>>    		return -E2BIG;
>>>    	}
>>>    
>>> -	fmt = to_dpu_format(msm_framebuffer_format(new_plane_state->fb));
>>> -
>>>    	max_linewidth = pdpu->catalog->caps->max_linewidth;
>>>    
>>> +	if (drm_plane_solid_fill_enabled(new_plane_state))
>>> +		fmt = dpu_get_dpu_format(DRM_FORMAT_ABGR8888);
>>> +	else
>>> +		fmt = to_dpu_format(msm_framebuffer_format(new_plane_state->fb));
>>> +
>>>    	if (drm_rect_width(&pipe_cfg->src_rect) > max_linewidth) {
>>>    		/*
>>>    		 * In parallel multirect case only the half of the usual width
>>> @@ -1082,21 +1087,32 @@ static void dpu_plane_sspp_atomic_update(struct drm_plane *plane)
>>>    	struct drm_crtc *crtc = state->crtc;
>>>    	struct drm_framebuffer *fb = state->fb;
>>>    	bool is_rt_pipe;
>>> -	const struct dpu_format *fmt =
>>> -		to_dpu_format(msm_framebuffer_format(fb));
>>> +	const struct dpu_format *fmt;
>>>    	struct dpu_sw_pipe_cfg *pipe_cfg = &pstate->pipe_cfg;
>>>    	struct dpu_sw_pipe_cfg *r_pipe_cfg = &pstate->r_pipe_cfg;
>>>    	struct dpu_kms *kms = _dpu_plane_get_kms(&pdpu->base);
>>>    	struct msm_gem_address_space *aspace = kms->base.aspace;
>>>    	struct dpu_hw_fmt_layout layout;
>>>    	bool layout_valid = false;
>>> -	int ret;
>>>    
>>> -	ret = dpu_format_populate_layout(aspace, fb, &layout);
>>> -	if (ret)
>>> -		DPU_ERROR_PLANE(pdpu, "failed to get format layout, %d\n", ret);
>>> -	else
>>> -		layout_valid = true;
>>> +	if (state->pixel_source == DRM_PLANE_PIXEL_SOURCE_FB && fb) {
>>> +		int ret;
>>> +
>>> +		fmt = to_dpu_format(msm_framebuffer_format(fb));
>>> +
>>> +		ret = dpu_format_populate_layout(aspace, fb, &layout);
>>> +		if (ret)
>>> +			DPU_ERROR_PLANE(pdpu, "failed to get format layout, %d\n", ret);
>>> +		else
>>> +			layout_valid = true;
>>> +
>>> +		DPU_DEBUG_PLANE(pdpu, "FB[%u] " DRM_RECT_FP_FMT "->crtc%u " DRM_RECT_FMT
>>> +				", %4.4s ubwc %d\n", fb->base.id, DRM_RECT_FP_ARG(&state->src),
>>> +				crtc->base.id, DRM_RECT_ARG(&state->dst),
>>> +				(char *)&fmt->base.pixel_format, DPU_FORMAT_IS_UBWC(fmt));
>>> +	} else {
>>> +		fmt = dpu_get_dpu_format(DRM_FORMAT_ABGR8888);
>>> +	}
>>>    
>>>    	pstate->pending = true;
>>>    
>>> @@ -1104,11 +1120,6 @@ static void dpu_plane_sspp_atomic_update(struct drm_plane *plane)
>>>    	pstate->needs_qos_remap |= (is_rt_pipe != pdpu->is_rt_pipe);
>>>    	pdpu->is_rt_pipe = is_rt_pipe;
>>>    
>>> -	DPU_DEBUG_PLANE(pdpu, "FB[%u] " DRM_RECT_FP_FMT "->crtc%u " DRM_RECT_FMT
>>> -			", %4.4s ubwc %d\n", fb->base.id, DRM_RECT_FP_ARG(&state->src),
>>> -			crtc->base.id, DRM_RECT_ARG(&state->dst),
>>> -			(char *)&fmt->base.pixel_format, DPU_FORMAT_IS_UBWC(fmt));
>>> -
>>>    	dpu_plane_sspp_update_pipe(plane, pipe, pipe_cfg, fmt,
>>>    				   drm_mode_vrefresh(&crtc->mode),
>>>    				   layout_valid ? &layout : NULL);
>>>    
>>
>