linux-kernel - Re: [PATCH v4 16/25] drm/msm/dpu: Require modeset if clone mode status changes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <x6q3jvoi452wql5wg3bizmrn657iyhyhrc3ffk5g3g26i6e4vo@n6hnqyjtuwg3>
Date: Fri, 20 Dec 2024 07:41:37 +0200
From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To: Jessica Zhang <quic_jesszhan@...cinc.com>
Cc: Rob Clark <robdclark@...il.com>, quic_abhinavk@...cinc.com, 
	Sean Paul <sean@...rly.run>, Marijn Suijten <marijn.suijten@...ainline.org>, 
	David Airlie <airlied@...il.com>, Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, 
	Maxime Ripard <mripard@...nel.org>, Thomas Zimmermann <tzimmermann@...e.de>, 
	Simona Vetter <simona@...ll.ch>, Simona Vetter <simona.vetter@...ll.ch>, 
	quic_ebharadw@...cinc.com, linux-arm-msm@...r.kernel.org, dri-devel@...ts.freedesktop.org, 
	freedreno@...ts.freedesktop.org, linux-kernel@...r.kernel.org, Rob Clark <robdclark@...omium.org>, 
	Ville Syrjälä <ville.syrjala@...ux.intel.com>
Subject: Re: [PATCH v4 16/25] drm/msm/dpu: Require modeset if clone mode
 status changes

On Mon, Dec 16, 2024 at 04:43:27PM -0800, Jessica Zhang wrote:
> If the clone mode enabled status is changing, a modeset needs to happen
> so that the resources can be reassigned
> 
> Signed-off-by: Jessica Zhang <quic_jesszhan@...cinc.com>
> ---
> 
> NOTE: As noted by Sima in the v1 [1], the DPU driver doesn't handle
> crtc_state->mode_changed correctly. However, fixing this is out of the
> scope of this series.
> 
> We will post a separate series addressing these issues across the driver

I'd rather fix the isssue first, as suggested by Sima, then we can see
how this function will evolve.

> 
> [1] https://lore.kernel.org/dri-devel/ZtW_S0j5AEr4g0QW@phenom.ffwll.local/
> ---
>  drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> index b063c8fe4c0594772d84401fa56c9c21afc0ad18..9bb920d28bae2706b3892c167fe2bec3fd8857f4 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> @@ -1297,6 +1297,8 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
>  {
>  	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
>  									  crtc);
> +	struct drm_crtc_state *old_crtc_state = drm_atomic_get_old_crtc_state(state,
> +									      crtc);
>  	struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
>  	struct dpu_crtc_state *cstate = to_dpu_crtc_state(crtc_state);
>  
> @@ -1308,6 +1310,8 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
>  	int rc = 0;
>  
>  	bool needs_dirtyfb = dpu_crtc_needs_dirtyfb(crtc_state);
> +	bool clone_mode_enabled = drm_crtc_in_clone_mode(old_crtc_state);
> +	bool clone_mode_requested = drm_crtc_in_clone_mode(crtc_state);
>  
>  	/* there might be cases where encoder needs a modeset too */
>  	drm_for_each_encoder_mask(drm_enc, crtc->dev, crtc_state->encoder_mask) {
> @@ -1315,6 +1319,10 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
>  			crtc_state->mode_changed = true;
>  	}
>  
> +	if ((clone_mode_requested && !clone_mode_enabled) ||
> +	    (!clone_mode_requested && clone_mode_enabled))
> +		crtc_state->mode_changed = true;
> +
>  	if (drm_atomic_crtc_needs_modeset(crtc_state)) {
>  		rc = dpu_crtc_assign_resources(crtc, crtc_state);
>  		if (rc < 0)
> 
> -- 
> 2.34.1
> 

-- 
With best wishes
Dmitry