[PATCH v2 8/9] drm/sun4i: dsi: Add burst support

Maxime Ripard
2019-02-08T09:55:48Z

From: Konstantin Sudakov <k.sudakov@integrasources.com>

The current driver doesn't support the DSI burst operation mode.

Let's add the needed quirks to make it work.

Signed-off-by: Konstantin Sudakov <k.sudakov@integrasources.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
---
drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 171 ++++++++++++++++++++------
1 file changed, 132 insertions(+), 39 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index e0288e7dc64e..4cb715dc9100 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -23,7 +23,9 @@
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_panel.h>

+#include "sun4i_crtc.h"
#include "sun4i_drv.h"
+#include "sun4i_tcon.h"
#include "sun6i_mipi_dsi.h"

#include <video/mipi_display.h>
@@ -32,6 +34,8 @@
#define SUN6I_DSI_CTL_EN BIT(0)

#define SUN6I_DSI_BASIC_CTL_REG 0x00c
+#define SUN6I_DSI_BASIC_CTL_TRAIL_INV(n) (((n) & 0xf) << 4)
+#define SUN6I_DSI_BASIC_CTL_TRAIL_FILL BIT(3)
#define SUN6I_DSI_BASIC_CTL_HBP_DIS BIT(2)
#define SUN6I_DSI_BASIC_CTL_HSA_HSE_DIS BIT(1)
#define SUN6I_DSI_BASIC_CTL_VIDEO_BURST BIT(0)
@@ -152,6 +156,8 @@

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

+#define SUN6I_DSI_SYNC_POINT 40
+
enum sun6i_dsi_start_inst {
DSI_START_LPRX,
DSI_START_LPTX,
@@ -366,13 +372,70 @@ static u16 sun6i_dsi_get_video_start_delay(struct sun6i_dsi *dsi,
return max_t(u16, delay, 1);
}

+static u16 sun6i_dsi_get_line_num(struct sun6i_dsi *dsi,
+ struct drm_display_mode *mode)
+{
+ struct mipi_dsi_device *device = dsi->device;
+ unsigned Bpp = mipi_dsi_pixel_format_to_bpp(device->format) / 8;
+
+ return mode->htotal * Bpp / device->lanes;
+}
+
+static u16 sun6i_dsi_get_drq_edge0(struct sun6i_dsi *dsi,
+ struct drm_display_mode *mode,
+ u16 line_num, u16 edge1)
+{
+ u16 edge0 = edge1;
+
+ edge0 += (mode->hdisplay + 40) * SUN6I_DSI_TCON_DIV / 8;
+
+ if (edge0 > line_num)
+ return edge0 - line_num;
+
+ return 1;
+}
+
+static u16 sun6i_dsi_get_drq_edge1(struct sun6i_dsi *dsi,
+ struct drm_display_mode *mode,
+ u16 line_num)
+{
+ struct mipi_dsi_device *device = dsi->device;
+ unsigned Bpp = mipi_dsi_pixel_format_to_bpp(device->format) / 8;
+ unsigned hbp = mode->htotal - mode->hsync_end;
+ u16 edge1;
+
+ edge1 = SUN6I_DSI_SYNC_POINT;
+ edge1 += (mode->hdisplay + hbp + 20) * Bpp / device->lanes;
+
+ if (edge1 > line_num)
+ return line_num;
+
+ return edge1;
+}
+
static void sun6i_dsi_setup_burst(struct sun6i_dsi *dsi,
struct drm_display_mode *mode)
{
struct mipi_dsi_device *device = dsi->device;
u32 val = 0;

- if ((mode->hsync_start - mode->hdisplay) > 20) {
+ if (device->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
+ u16 line_num = sun6i_dsi_get_line_num(dsi, mode);
+ u16 edge0, edge1;
+
+ edge1 = sun6i_dsi_get_drq_edge1(dsi, mode, line_num);
+ edge0 = sun6i_dsi_get_drq_edge0(dsi, mode, line_num, edge1);
+
+ regmap_write(dsi->regs, SUN6I_DSI_BURST_DRQ_REG,
+ SUN6I_DSI_BURST_DRQ_EDGE0(edge0) |
+ SUN6I_DSI_BURST_DRQ_EDGE1(edge1));
+
+ regmap_write(dsi->regs, SUN6I_DSI_BURST_LINE_REG,
+ SUN6I_DSI_BURST_LINE_NUM(line_num) |
+ SUN6I_DSI_BURST_LINE_SYNC_POINT(SUN6I_DSI_SYNC_POINT));
+
+ val = SUN6I_DSI_TCON_DRQ_ENABLE_MODE;
+ } else if ((mode->hsync_start - mode->hdisplay) > 20) {
/* Maaaaaagic */
u16 drq = (mode->hsync_start - mode->hdisplay) - 20;

@@ -389,8 +452,19 @@ static void sun6i_dsi_setup_burst(struct sun6i_dsi *dsi,
static void sun6i_dsi_setup_inst_loop(struct sun6i_dsi *dsi,
struct drm_display_mode *mode)
{
+ struct mipi_dsi_device *device = dsi->device;
u16 delay = 50 - 1;

+ if (device->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
+ delay = (mode->htotal - mode->hdisplay) * 150;
+ delay /= (mode->clock / 1000) * 8;
+ delay -= 50;
+ }
+
+ regmap_write(dsi->regs, SUN6I_DSI_INST_LOOP_SEL_REG,
+ 2 << (4 * DSI_INST_ID_LP11) |
+ 3 << (4 * DSI_INST_ID_DLY));
+
regmap_write(dsi->regs, SUN6I_DSI_INST_LOOP_NUM_REG(0),
SUN6I_DSI_INST_LOOP_NUM_N0(50 - 1) |
SUN6I_DSI_INST_LOOP_NUM_N1(delay));
@@ -457,52 +531,71 @@ 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;
+ u32 basic_ctl = 0;
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
- */
+ if (device->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
+ hsa = 0;
+ hbp = 0;
+ hfp = 0;
+ hblk = mode->hdisplay * Bpp;
+ vblk = 0;
+ basic_ctl = SUN6I_DSI_BASIC_CTL_VIDEO_BURST |
+ SUN6I_DSI_BASIC_CTL_HSA_HSE_DIS |
+ SUN6I_DSI_BASIC_CTL_HBP_DIS;
+
+ if (device->lanes == 4)
+ basic_ctl |= SUN6I_DSI_BASIC_CTL_TRAIL_FILL |
+ SUN6I_DSI_BASIC_CTL_TRAIL_INV(0xc);
+ } 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);
-
- /*
- * The frontporch is set using a blanking packet (4 bytes +
- * payload + 2 bytes). Its minimal size is therefore 6 bytes
- */
+ 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);
-
- /*
- * The blanking is set using a sync event (4 bytes) and a
- * blanking packet (4 bytes + payload + 2 bytes). Its minimal
- * size is therefore 10 bytes.
- */
+ hfp = max((unsigned int)HFP_PACKET_OVERHEAD,
+ (mode->hsync_start - mode->hdisplay) * Bpp - HFP_PACKET_OVERHEAD);
+
+ /*
+ * The blanking is set using a sync event (4 bytes)
+ * and a blanking packet (4 bytes + payload + 2
+ * bytes). Its minimal size is therefore 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);
-
- /*
- * And I'm not entirely sure what vblk is about. The driver in
- * Allwinner BSP is using a rather convoluted calculation
- * there only for 4 lanes. However, using 0 (the !4 lanes
- * case) even with a 4 lanes screen seems to work...
- */
- vblk = 0;
+ hblk = max((unsigned int)HBLK_PACKET_OVERHEAD,
+ (mode->htotal - (mode->hsync_end - mode->hsync_start)) * Bpp -
+ HBLK_PACKET_OVERHEAD);
+
+ /*
+ * And I'm not entirely sure what vblk is about. The driver in
+ * Allwinner BSP is using a rather convoluted calculation
+ * there only for 4 lanes. However, using 0 (the !4 lanes
+ * case) even with a 4 lanes screen seems to work...
+ */
+ vblk = 0;
+ }

/* How many bytes do we need to send all payloads? */
bytes = max_t(size_t, max(max(hfp, hblk), max(hsa, hbp)), vblk);
@@ -510,7 +603,7 @@ static void sun6i_dsi_setup_timings(struct sun6i_dsi *dsi,
if (WARN_ON(!buffer))
return;

- regmap_write(dsi->regs, SUN6I_DSI_BASIC_CTL_REG, 0);
+ regmap_write(dsi->regs, SUN6I_DSI_BASIC_CTL_REG, basic_ctl);

regmap_write(dsi->regs, SUN6I_DSI_SYNC_HSS_REG,
sun6i_dsi_build_sync_pkt(MIPI_DSI_H_SYNC_START,