[PATCH v2 03/12] drm/sun4i: sun6i_mipi_dsi: Setup burst mode timings

From: Jagan Teki
Date: Fri Nov 16 2018 - 11:40:05 EST


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

Reference code taken from BSP (from linux-sunxi/
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@xxxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 128 +++++++++++++++----------
1 file changed, 80 insertions(+), 48 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 3ac002c4d8b3..efd08bfd0cb8 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -153,6 +153,14 @@

#define SUN6I_DSI_CMD_TX_REG(n) (0x300 + (n) * 0x04)

+struct sun6i_dsi_timings {
+ u16 hsa;
+ u16 hbp;
+ u16 hblk;
+ u16 hfp;
+ u16 vblk;
+};
+
enum sun6i_dsi_start_inst {
DSI_START_LPRX,
DSI_START_LPTX,
@@ -379,6 +387,60 @@ static u16 sun6i_dsi_get_timings_vblk(struct sun6i_dsi *dsi,
return vblk;
}

+static void sun6i_dsi_get_timings(struct sun6i_dsi *dsi,
+ struct drm_display_mode *mode,
+ struct sun6i_dsi_timings *timings)
+{
+ struct mipi_dsi_device *device = dsi->device;
+ unsigned int Bpp = mipi_dsi_pixel_format_to_bpp(device->format) / 8;
+ u16 hsa, hbp, hblk, hfp, vblk;
+
+ /*
+ * 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
+ */
+#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
+ */
+#define HBLK_PACKET_OVERHEAD 10
+ hblk = max((unsigned int)HBLK_PACKET_OVERHEAD,
+ (mode->htotal - (mode->hsync_end - mode->hsync_start)) *
+ Bpp - HBLK_PACKET_OVERHEAD);
+
+ /*
+ * The frontporch is set using a blanking packet (4 bytes +
+ * payload + 2 bytes). Its minimal size is therefore 6 bytes
+ */
+#define HFP_PACKET_OVERHEAD 6
+ hfp = max((unsigned int)HFP_PACKET_OVERHEAD,
+ (mode->hsync_start - mode->hdisplay) * Bpp -
+ HFP_PACKET_OVERHEAD);
+
+ vblk = sun6i_dsi_get_timings_vblk(dsi, mode, hblk);
+
+ timings->hsa = hsa;
+ timings->hbp = hbp;
+ timings->hblk = hblk;
+ timings->hfp = hfp;
+ timings->vblk = vblk;
+}
+
static u16 sun6i_dsi_setup_inst_delay(struct sun6i_dsi *dsi,
struct drm_display_mode *mode)
{
@@ -506,52 +568,22 @@ static void sun6i_dsi_setup_timings(struct sun6i_dsi *dsi,
{
struct mipi_dsi_device *device = dsi->device;
unsigned int Bpp = mipi_dsi_pixel_format_to_bpp(device->format) / 8;
- u16 hbp, hfp, hsa, hblk, vblk;
+ struct sun6i_dsi_timings timings;
size_t bytes;
u8 *buffer;

/* 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
- */
-#define HSA_PACKET_OVERHEAD 10
- hsa = max((unsigned int)HSA_PACKET_OVERHEAD,
- (mode->hsync_end - mode->hsync_start) * Bpp - HSA_PACKET_OVERHEAD);
+ memset(&timings, 0, sizeof(timings));

- /*
- * 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);
-
- /*
- * The frontporch is set using a blanking packet (4 bytes +
- * payload + 2 bytes). Its minimal size is therefore 6 bytes
- */
-#define HFP_PACKET_OVERHEAD 6
- hfp = max((unsigned int)HFP_PACKET_OVERHEAD,
- (mode->hsync_start - mode->hdisplay) * Bpp -
- HFP_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((unsigned int)HBLK_PACKET_OVERHEAD,
- (mode->htotal - (mode->hsync_end - mode->hsync_start)) *
- Bpp - HBLK_PACKET_OVERHEAD);
-
- vblk = sun6i_dsi_get_timings_vblk(dsi, mode, hblk);
+ if (device->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
+ timings.hblk = (mode->hdisplay * Bpp);
+ else
+ sun6i_dsi_get_timings(dsi, mode, &timings);

/* How many bytes do we need to send all payloads? */
- bytes = max_t(size_t, max(max(hfp, hblk), max(hsa, hbp)), vblk);
+ bytes = max_t(size_t, max(max(timings.hfp, timings.hblk),
+ max(timings.hsa, timings.hbp)), timings.vblk);
buffer = kmalloc(bytes, GFP_KERNEL);
if (WARN_ON(!buffer))
return;
@@ -590,33 +622,33 @@ static void sun6i_dsi_setup_timings(struct sun6i_dsi *dsi,

/* sync */
regmap_write(dsi->regs, SUN6I_DSI_BLK_HSA0_REG,
- sun6i_dsi_build_blk0_pkt(device->channel, hsa));
+ sun6i_dsi_build_blk0_pkt(device->channel, timings.hsa));
regmap_write(dsi->regs, SUN6I_DSI_BLK_HSA1_REG,
- sun6i_dsi_build_blk1_pkt(0, buffer, hsa));
+ sun6i_dsi_build_blk1_pkt(0, buffer, timings.hsa));

/* backporch */
regmap_write(dsi->regs, SUN6I_DSI_BLK_HBP0_REG,
- sun6i_dsi_build_blk0_pkt(device->channel, hbp));
+ sun6i_dsi_build_blk0_pkt(device->channel, timings.hbp));
regmap_write(dsi->regs, SUN6I_DSI_BLK_HBP1_REG,
- sun6i_dsi_build_blk1_pkt(0, buffer, hbp));
+ sun6i_dsi_build_blk1_pkt(0, buffer, timings.hbp));

/* frontporch */
regmap_write(dsi->regs, SUN6I_DSI_BLK_HFP0_REG,
- sun6i_dsi_build_blk0_pkt(device->channel, hfp));
+ sun6i_dsi_build_blk0_pkt(device->channel, timings.hfp));
regmap_write(dsi->regs, SUN6I_DSI_BLK_HFP1_REG,
- sun6i_dsi_build_blk1_pkt(0, buffer, hfp));
+ sun6i_dsi_build_blk1_pkt(0, buffer, timings.hfp));

/* hblk */
regmap_write(dsi->regs, SUN6I_DSI_BLK_HBLK0_REG,
- sun6i_dsi_build_blk0_pkt(device->channel, hblk));
+ sun6i_dsi_build_blk0_pkt(device->channel, timings.hblk));
regmap_write(dsi->regs, SUN6I_DSI_BLK_HBLK1_REG,
- sun6i_dsi_build_blk1_pkt(0, buffer, hblk));
+ sun6i_dsi_build_blk1_pkt(0, buffer, timings.hblk));

/* vblk */
regmap_write(dsi->regs, SUN6I_DSI_BLK_VBLK0_REG,
- sun6i_dsi_build_blk0_pkt(device->channel, vblk));
+ sun6i_dsi_build_blk0_pkt(device->channel, timings.vblk));
regmap_write(dsi->regs, SUN6I_DSI_BLK_VBLK1_REG,
- sun6i_dsi_build_blk1_pkt(0, buffer, vblk));
+ sun6i_dsi_build_blk1_pkt(0, buffer, timings.vblk));

kfree(buffer);
}
--
2.18.0.321.gffc6fa0e3