From mboxrd@z Thu Jan  1 00:00:00 1970
From: Maxime Ripard <maxime.ripard-LDxbnhwyfcJBDgjK7y7TUQ@public.gmane.org>
Subject: Re: [PATCH v2 01/12] drm/sun4i: sun6i_mipi_dsi: Compute
 burst mode loop N1 instruction delay
Date: Mon, 19 Nov 2018 09:27:07 +0100
Message-ID: <20181119082707.kbsw2gyntxxbh6no@flea>
References: <20181116163916.29621-1-jagan@amarulasolutions.com>
 <20181116163916.29621-2-jagan@amarulasolutions.com>
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To: Jagan Teki <jagan-dyjBcgdgk7Pe9wHmmfpqLFaTQe2KTcn/@public.gmane.org>
Cc: Maarten Lankhorst <maarten.lankhorst-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>, Sean Paul <sean-p7yTbzM4H96eqtR555YLDQ@public.gmane.org>, David Airlie <airlied-cv59FeDIM0c@public.gmane.org>, Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Chen-Yu Tsai <wens-jdAy2FN1RRM@public.gmane.org>, Icenowy Zheng <icenowy-h8G6r0blFSE@public.gmane.org>, Jernej Skrabec <jernej.skrabec-gGgVlfcn5nU@public.gmane.org>, Vasily Khoruzhick <anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Thierry Reding <thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Michael Trimarchi <michael-dyjBcgdgk7Pe9wHmmfpqLFaTQe2KTcn/@public.gmane.org>, TL Lim <tllim-F7SikzrIcFYdnm+yROfE0A@public.gmane.org>, linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, linux-amarula-dyjBcgdgk7Pe9wHmmfpqLFaTQe2KTcn/@public.gmane.org
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On Fri, Nov 16, 2018 at 10:09:05PM +0530, Jagan Teki wrote:
> Loop N1 instruction delay for burst mode lcd panel are
> computed as per BSP code.
> 
> Reference code is available in BSP (from linux-sunxi
> drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c)
> 
> dsi_dev[sel]->dsi_inst_loop_num.bits.loop_n1=
> (panel->lcd_ht-panel->lcd_x)*(150)/(panel->lcd_dclk_freq*8) - 50;
> => (((mode->htotal - mode->hdisplay) * 150) /
>      ((mode->clock / 1000) * 8)) - 50;
> 
> So use the similar computation for loop N1 delay.
> 
> Signed-off-by: Jagan Teki <jagan-dyjBcgdgk7Pe9wHmmfpqLFaTQe2KTcn/@public.gmane.org>

*why* are you doing this? What is it fixing? on which devices?

Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
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