Re: [RFC AFBC 09/12] drm/arm/malidp:- Writeback framebuffer does not support any modifiers

From: Liviu Dudau <Liviu.Dudau@arm.com>
To: Ayan Halder <Ayan.Halder@arm.com>
Cc: Brian Starkey <Brian.Starkey@arm.com>,
	"malidp@foss.arm.com" <malidp@foss.arm.com>,
	"airlied@linux.ie" <airlied@linux.ie>,
	"dri-devel@lists.freedesktop.org"
	<dri-devel@lists.freedesktop.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"maxime.ripard@bootlin.com" <maxime.ripard@bootlin.com>,
	"sean@poorly.run" <sean@poorly.run>,
	"maarten.lankhorst@linux.intel.com" 
	<maarten.lankhorst@linux.intel.com>,
	"corbet@lwn.net" <corbet@lwn.net>,
	"mchehab+samsung@kernel.org" <mchehab+samsung@kernel.org>,
	"gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
	"davem@davemloft.net" <davem@davemloft.net>,
	"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
	"nicolas.ferre@microchip.com" <nicolas.ferre@microchip.com>,
	"arnd@arndb.de" <arnd@arndb.de>,
	"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
	nd <nd@arm.com>
Subject: Re: [RFC AFBC 09/12] drm/arm/malidp:- Writeback framebuffer does not support any modifiers
Date: Tue, 4 Dec 2018 17:50:58 +0000	[thread overview]
Message-ID: <20181204175058.GQ988@e110455-lin.cambridge.arm.com> (raw)
In-Reply-To: <1543836703-8491-10-git-send-email-ayan.halder@arm.com>

On Mon, Dec 03, 2018 at 11:32:03AM +0000, Ayan Halder wrote:
> In malidp, the writeback pipeline does not support writing crtc output
> to a framebuffer with modifiers ie the memory writeback content is
> devoid of any compression or tiling, etc.
> So we have added a commit check in memory writeback encoder helper function
> to validate if the framebuffer has any modifier and if so, return EINVAL.
> 
> Signed-off-by: Ayan Kumar halder <ayan.halder@arm.com>

Acked-by: Liviu Dudau <liviu.dudau@arm.com>

> ---
>  drivers/gpu/drm/arm/malidp_mw.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/gpu/drm/arm/malidp_mw.c b/drivers/gpu/drm/arm/malidp_mw.c
> index 0484744..90c964a 100644
> --- a/drivers/gpu/drm/arm/malidp_mw.c
> +++ b/drivers/gpu/drm/arm/malidp_mw.c
> @@ -141,6 +141,11 @@ malidp_mw_encoder_atomic_check(struct drm_encoder *encoder,
>  		return -EINVAL;
>  	}
>  
> +	if (fb->modifier) {
> +		DRM_DEBUG_KMS("Writeback framebuffer does not support modifiers\n");
> +		return -EINVAL;
> +	}
> +
>  	mw_state->format =
>  		malidp_hw_get_format_id(&malidp->dev->hw->map, SE_MEMWRITE,
>  					fb->format->format, !!fb->modifier);
> -- 
> 2.7.4
> 

-- 
====================
| I would like to |
| fix the world,  |
| but they're not |
| giving me the   |
 \ source code!  /
  ---------------
    ¯\_(ツ)_/¯