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Date:   Thu, 2 Nov 2023 15:55:59 +0100
From:   Francesco Dolcini <francesco@dolcini.it>
To:     Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Cc:     Aradhya Bhatia <a-bhatia1@ti.com>,
        Devarsh Thakkar <devarsht@ti.com>,
        Jyri Sarha <jyri.sarha@iki.fi>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Subject: Re: [PATCH 10/10] drm/tidss: Fix atomic_flush check
Message-ID: <ZUO4f/OjdYW4Paxu@francesco-nb.int.toradex.com>
References: <20231101-tidss-probe-v1-0-45149e0f9415@ideasonboard.com>
 <20231101-tidss-probe-v1-10-45149e0f9415@ideasonboard.com>
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On Wed, Nov 01, 2023 at 11:17:47AM +0200, Tomi Valkeinen wrote:
> tidss_crtc_atomic_flush() checks if the crtc is enabled, and if not,
> returns immediately as there's no reason to do any register changes.
> 
> However, the code checks for 'crtc->state->enable', which does not
> reflect the actual HW state. We should instead look at the
> 'crtc->state->active' flag.
> 
> This causes the tidss_crtc_atomic_flush() to proceed with the flush even
> if the active state is false, which then causes us to hit the
> WARN_ON(!crtc->state->event) check.
> 
> Fix this by checking the active flag, and while at it, fix the related
> debug print which had "active" and "needs modeset" wrong way.

Candidate for stable? Add a Fixes tag?

Francesco