[PATCH 03/10] drm/sun4i: sun6i_mipi_dsi: Setup burst mode timings

From: Jagan Teki <jagan@amarulasolutions.com>
To: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Maxime Ripard <maxime.ripard@bootlin.com>,
	Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
	Rob Herring <robh+dt@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
	Icenowy Zheng <icenowy@aosc.io>,
	Jernej Skrabec <jernej.skrabec@siol.net>,
	Vasily Khoruzhick <anarsoul@gmail.com>,
	Thierry Reding <thierry.reding@gmail.com>,
	Mark Rutland <mark.rutland@arm.com>,
	dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	Michael Trimarchi <michael@amarulasolutions.com>,
	TL Lim <tllim@pine64.org>,
	linux-sunxi@googlegroups.com
Cc: Jagan Teki <jagan@amarulasolutions.com>
Subject: [PATCH 03/10] drm/sun4i: sun6i_mipi_dsi: Setup burst mode timings
Date: Sat,  3 Nov 2018 15:38:53 +0530	[thread overview]
Message-ID: <20181103100900.30313-4-jagan@amarulasolutions.com> (raw)
In-Reply-To: <20181103100900.30313-1-jagan@amarulasolutions.com>

Burst mode display timings are different from convectional
video mode so update the horizontal and vertical timings.

Reference code taken from BSP
(in drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c)
dsi_hsa  = 0;
dsi_hbp  = 0;
dsi_hact = x*dsi_pixel_bits[format]/8;
dsi_hblk = dsi_hact;
dsi_hfp  = 0;
dsi_vblk = 0;

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 108 ++++++++++++++-----------
 1 file changed, 60 insertions(+), 48 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 077b57ec964c..4965b2c71e4c 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -479,59 +479,71 @@ static void sun6i_dsi_setup_timings(struct sun6i_dsi *dsi,
 
 	/* Do all timing calculations up front to allocate buffer space */
 
-	/*
-	 * A sync period is composed of a blanking packet (4 bytes +
-	 * payload + 2 bytes) and a sync event packet (4 bytes). Its
-	 * minimal size is therefore 10 bytes
-	 */
+	if (device->mode_flags == MIPI_DSI_MODE_VIDEO_BURST) {
+		hsa = 0;
+		hbp = 0;
+		hblk = mode->hdisplay * Bpp;
+		hfp = 0;
+		vblk = 0;
+	} else {
+		/*
+		 * A sync period is composed of a blanking packet (4 bytes +
+		 * payload + 2 bytes) and a sync event packet (4 bytes). Its
+		 * minimal size is therefore 10 bytes
+		 */
 #define HSA_PACKET_OVERHEAD	10
-	hsa = max((unsigned int)HSA_PACKET_OVERHEAD,
-		  (mode->hsync_end - mode->hsync_start) * Bpp - HSA_PACKET_OVERHEAD);
-
-	/*
-	 * The backporch is set using a blanking packet (4 bytes +
-	 * payload + 2 bytes). Its minimal size is therefore 6 bytes
-	 */
+		hsa = max((unsigned int)HSA_PACKET_OVERHEAD,
+			  (mode->hsync_end - mode->hsync_start) * Bpp -
+			  HSA_PACKET_OVERHEAD);
+
+		/*
+		 * The backporch is set using a blanking packet (4 bytes +
+		 * payload + 2 bytes). Its minimal size is therefore 6 bytes
+		 */
 #define HBP_PACKET_OVERHEAD	6
-	hbp = max((unsigned int)HBP_PACKET_OVERHEAD,
-		  (mode->htotal - mode->hsync_end) * Bpp - HBP_PACKET_OVERHEAD);
-
-	/*
-	 * hblk seems to be the line + porches length.
-	 * The blank is set using a blanking packet (4 bytes + 4 bytes +
-	 * payload + 2 bytes). So minimal size is 10 bytes
-	 */
+		hbp = max((unsigned int)HBP_PACKET_OVERHEAD,
+			  (mode->htotal - mode->hsync_end) * Bpp -
+			  HBP_PACKET_OVERHEAD);
+
+		/*
+		 * hblk seems to be the line + porches length.
+		 * The blank is set using a blanking packet (4 bytes + 4 bytes
+		 * + payload + 2 bytes). So minimal size is 10 bytes
+		 */
 #define HBLK_PACKET_OVERHEAD	10
-	hblk_max = (mode->htotal - (mode->hsync_end - mode->hsync_start)) * Bpp;
-	hblk_max -= HBLK_PACKET_OVERHEAD;
-	hblk = max_t(unsigned int, HBLK_PACKET_OVERHEAD, hblk_max);
-
-	/*
-	 * The frontporch is set using a blanking packet (4 bytes +
-	 * payload + 2 bytes). Its minimal size is therefore 6 bytes
-	 *
-	 * According to BSP code, extra 10 bytes(which is hblk packet overhead)
-	 * is adding for hfp packet overhead since hfp depends on hblk.
-	 */
+		hblk_max = (mode->htotal -
+			   (mode->hsync_end - mode->hsync_start)) * Bpp;
+		hblk_max -= HBLK_PACKET_OVERHEAD;
+		hblk = max_t(unsigned int, HBLK_PACKET_OVERHEAD, hblk_max);
+
+		/*
+		 * The frontporch is set using a blanking packet (4 bytes +
+		 * payload + 2 bytes). Its minimal size is therefore 6 bytes
+		 *
+		 * According to BSP code, extra 10 bytes(which is hblk packet
+		 * overhead) is adding for hfp packet overhead since hfp
+		 * depends on hblk.
+		 */
 #define HFP_PACKET_OVERHEAD	6
-	hfp_pkt_overhead = (HFP_PACKET_OVERHEAD + HBLK_PACKET_OVERHEAD);
-	hfp = max((unsigned int)hfp_pkt_overhead,
-		  (mode->hsync_start - mode->hdisplay) * Bpp -
-		  hfp_pkt_overhead);
-
-	/*
-	 * The vertical blank is set using a blanking packet (4 bytes +
-	 * payload + 2 bytes). Its minimal size is therefore 6 bytes
-	 */
+		hfp_pkt_overhead = (HFP_PACKET_OVERHEAD + HBLK_PACKET_OVERHEAD);
+		hfp = max((unsigned int)hfp_pkt_overhead,
+			  (mode->hsync_start - mode->hdisplay) * Bpp -
+			  hfp_pkt_overhead);
+
+		/*
+		 * The vertical blank is set using a blanking packet (4 bytes +
+		 * payload + 2 bytes). Its minimal size is therefore 6 bytes
+		 */
 #define VBLK_PACKET_OVERHEAD	6
-	if (device->lanes == 4) {
-		int tmp;
-
-		tmp = (mode->htotal * Bpp) * mode->vtotal -
-		      (hblk + VBLK_PACKET_OVERHEAD);
-		vblk = (device->lanes - tmp % device->lanes);
-	} else {
-		vblk = 0;
+		if (device->lanes == 4) {
+			int tmp;
+
+			tmp = (mode->htotal * Bpp) * mode->vtotal -
+			      (hblk + VBLK_PACKET_OVERHEAD);
+			vblk = (device->lanes - tmp % device->lanes);
+		} else {
+			vblk = 0;
+		}
 	}
 
 	/* How many bytes do we need to send all payloads? */
-- 
2.18.0.321.gffc6fa0e3

