[PATCH 4/6] drm/bridge: tc358767: fix timing calculations
Andrey Gusakov
andrey.gusakov at cogentembedded.com
Thu Jul 27 12:47:34 UTC 2017
Fields in HTIM01 and HTIM02 regs should be even.
Recomended thresh_dly value is max_tu_symbol.
Signed-off-by: Andrey Gusakov <andrey.gusakov at cogentembedded.com>
---
drivers/gpu/drm/bridge/tc358767.c | 34 ++++++++++++++++++++--------------
1 file changed, 20 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
index 4aee6178d889..c657a00af508 100644
--- a/drivers/gpu/drm/bridge/tc358767.c
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -659,6 +659,14 @@ static int tc_set_video_mode(struct tc_data *tc, struct drm_display_mode *mode)
int lower_margin = mode->vsync_start - mode->vdisplay;
int vsync_len = mode->vsync_end - mode->vsync_start;
+ /*
+ * Recommended maximum number of symbols transferred in a transfer unit:
+ * DIV_ROUND_UP((input active video bandwidth in bytes) * tu_size,
+ * (output active video bandwidth in bytes))
+ * Must be less than tu_size.
+ */
+ max_tu_symbol = TU_SIZE_RECOMMENDED - 1;
+
dev_dbg(tc->dev, "set mode %dx%d\n",
mode->hdisplay, mode->vdisplay);
dev_dbg(tc->dev, "H margin %d,%d sync %d\n",
@@ -668,13 +676,18 @@ static int tc_set_video_mode(struct tc_data *tc, struct drm_display_mode *mode)
dev_dbg(tc->dev, "total: %dx%d\n", mode->htotal, mode->vtotal);
- /* LCD Ctl Frame Size */
- tc_write(VPCTRL0, (0x40 << 20) /* VSDELAY */ |
+ /*
+ * LCD Ctl Frame Size
+ * datasheet is not clear of vsdelay in case of DPI
+ * assume we do not need any delay when DPI is a source of
+ * sync signals
+ */
+ tc_write(VPCTRL0, (0 << 20) /* VSDELAY */ |
OPXLFMT_RGB888 | FRMSYNC_DISABLED | MSF_DISABLED);
- tc_write(HTIM01, (left_margin << 16) | /* H back porch */
- (hsync_len << 0)); /* Hsync */
- tc_write(HTIM02, (right_margin << 16) | /* H front porch */
- (mode->hdisplay << 0)); /* width */
+ tc_write(HTIM01, (ALIGN(left_margin, 2) << 16) | /* H back porch */
+ (ALIGN(hsync_len, 2) << 0)); /* Hsync */
+ tc_write(HTIM02, (ALIGN(right_margin, 2) << 16) | /* H front porch */
+ (ALIGN(mode->hdisplay, 2) << 0)); /* width */
tc_write(VTIM01, (upper_margin << 16) | /* V back porch */
(vsync_len << 0)); /* Vsync */
tc_write(VTIM02, (lower_margin << 16) | /* V front porch */
@@ -693,7 +706,7 @@ static int tc_set_video_mode(struct tc_data *tc, struct drm_display_mode *mode)
/* DP Main Stream Attributes */
vid_sync_dly = hsync_len + left_margin + mode->hdisplay;
tc_write(DP0_VIDSYNCDELAY,
- (0x003e << 16) | /* thresh_dly */
+ (max_tu_symbol << 16) | /* thresh_dly */
(vid_sync_dly << 0));
tc_write(DP0_TOTALVAL, (mode->vtotal << 16) | (mode->htotal));
@@ -709,13 +722,6 @@ static int tc_set_video_mode(struct tc_data *tc, struct drm_display_mode *mode)
tc_write(DPIPXLFMT, VS_POL_ACTIVE_LOW | HS_POL_ACTIVE_LOW |
DE_POL_ACTIVE_HIGH | SUB_CFG_TYPE_CONFIG1 | DPI_BPP_RGB888);
- /*
- * Recommended maximum number of symbols transferred in a transfer unit:
- * DIV_ROUND_UP((input active video bandwidth in bytes) * tu_size,
- * (output active video bandwidth in bytes))
- * Must be less than tu_size.
- */
- max_tu_symbol = TU_SIZE_RECOMMENDED - 1;
tc_write(DP0_MISC, (max_tu_symbol << 23) | (TU_SIZE_RECOMMENDED << 16) |
BPC_8);
--
2.13.0
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