[PATCH] drm/mcde: Some fixes to handling video mode
Linus Walleij
linus.walleij at linaro.org
Mon Sep 2 07:17:14 UTC 2019
The video DSI mode had not really been tested. These fixes makes
it more likely to work on real hardware:
- Set the HS clock to something the video mode reported by the
panel can handle rather than the max HS rate.
- Put the active width (x width) in the right bits and the VSA
(vertical sync active) in the right bits (those were swapped).
- Calculate the packet sizes in bytes as in the vendor driver,
rather than in bits.
- Handle negative result in front/back/sync packages and fall
back to zero like in the vendor driver.
Cc: Stephan Gerhold <stephan at gerhold.net>
Fixes: 5fc537bfd000 ("drm/mcde: Add new driver for ST-Ericsson MCDE")
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
drivers/gpu/drm/mcde/mcde_dsi.c | 60 ++++++++++++++++++++++-----------
1 file changed, 41 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/drm/mcde/mcde_dsi.c b/drivers/gpu/drm/mcde/mcde_dsi.c
index 90659d190d78..f5079f0e24ca 100644
--- a/drivers/gpu/drm/mcde/mcde_dsi.c
+++ b/drivers/gpu/drm/mcde/mcde_dsi.c
@@ -365,11 +365,12 @@ void mcde_dsi_te_request(struct mipi_dsi_device *mdsi)
static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
const struct drm_display_mode *mode)
{
- u8 bpp = mipi_dsi_pixel_format_to_bpp(d->mdsi->format);
+ /* cpp, characters per pixel, number of bytes per pixel */
+ u8 cpp = mipi_dsi_pixel_format_to_bpp(d->mdsi->format) / 8;
u64 bpl;
- u32 hfp;
- u32 hbp;
- u32 hsa;
+ int hfp;
+ int hbp;
+ int hsa;
u32 blkline_pck, line_duration;
u32 blkeol_pck, blkeol_duration;
u32 val;
@@ -420,13 +421,13 @@ static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
writel(val, d->regs + DSI_VID_MAIN_CTL);
/* Vertical frame parameters are pretty straight-forward */
- val = mode->vdisplay << DSI_VID_VSIZE_VSA_LENGTH_SHIFT;
+ val = mode->vdisplay << DSI_VID_VSIZE_VACT_LENGTH_SHIFT;
/* vertical front porch */
val |= (mode->vsync_start - mode->vdisplay)
<< DSI_VID_VSIZE_VFP_LENGTH_SHIFT;
/* vertical sync active */
val |= (mode->vsync_end - mode->vsync_start)
- << DSI_VID_VSIZE_VACT_LENGTH_SHIFT;
+ << DSI_VID_VSIZE_VSA_LENGTH_SHIFT;
/* vertical back porch */
val |= (mode->vtotal - mode->vsync_end)
<< DSI_VID_VSIZE_VBP_LENGTH_SHIFT;
@@ -437,21 +438,25 @@ static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
* horizontal resolution is given in pixels and must be re-calculated
* into bytes since this is what the hardware expects.
*
+ * hfp = horizontal front porch in bytes
+ * hbp = horizontal back porch in bytes
+ * hsa = horizontal sync active in bytes
+ *
* 6 + 2 is HFP header + checksum
*/
- hfp = (mode->hsync_start - mode->hdisplay) * bpp - 6 - 2;
+ hfp = (mode->hsync_start - mode->hdisplay) * cpp - 6 - 2;
if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
/*
* 6 is HBP header + checksum
* 4 is RGB header + checksum
*/
- hbp = (mode->htotal - mode->hsync_end) * bpp - 4 - 6;
+ hbp = (mode->htotal - mode->hsync_end) * cpp - 4 - 6;
/*
* 6 is HBP header + checksum
* 4 is HSW packet bytes
* 4 is RGB header + checksum
*/
- hsa = (mode->hsync_end - mode->hsync_start) * bpp - 4 - 4 - 6;
+ hsa = (mode->hsync_end - mode->hsync_start) * cpp - 4 - 4 - 6;
} else {
/*
* HBP includes both back porch and sync
@@ -459,11 +464,23 @@ static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
* 4 is HSW packet bytes
* 4 is RGB header + checksum
*/
- hbp = (mode->htotal - mode->hsync_start) * bpp - 4 - 4 - 6;
- /* HSA is not considered in this mode and set to 0 */
+ hbp = (mode->htotal - mode->hsync_start) * cpp - 4 - 4 - 6;
+ /* HSA is not present in this mode and set to 0 */
+ hsa = 0;
+ }
+ if (hfp < 0) {
+ dev_info(d->dev, "hfp negative, set to 0\n");
+ hfp = 0;
+ }
+ if (hbp < 0) {
+ dev_info(d->dev, "hbp negative, set to 0\n");
+ hbp = 0;
+ }
+ if (hsa < 0) {
+ dev_info(d->dev, "hsa negative, set to 0\n");
hsa = 0;
}
- dev_dbg(d->dev, "hfp: %u, hbp: %u, hsa: %u\n",
+ dev_dbg(d->dev, "hfp: %u, hbp: %u, hsa: %u bytes\n",
hfp, hbp, hsa);
/* Frame parameters: horizontal sync active */
@@ -475,7 +492,7 @@ static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
writel(val, d->regs + DSI_VID_HSIZE1);
/* RGB data length (bytes on one scanline) */
- val = mode->hdisplay * (bpp / 8);
+ val = mode->hdisplay * cpp;
writel(val, d->regs + DSI_VID_HSIZE2);
/* TODO: further adjustments for TVG mode here */
@@ -507,7 +524,7 @@ static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
}
line_duration = (blkline_pck + 6) / d->mdsi->lanes;
- dev_dbg(d->dev, "line duration %u\n", line_duration);
+ dev_dbg(d->dev, "line duration %u bytes\n", line_duration);
val = line_duration << DSI_VID_DPHY_TIME_REG_LINE_DURATION_SHIFT;
/*
* This is the time to perform LP->HS on D-PHY
@@ -517,17 +534,18 @@ static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
writel(val, d->regs + DSI_VID_DPHY_TIME);
/* Calculate block end of line */
- blkeol_pck = bpl - mode->hdisplay * bpp - 6;
+ blkeol_pck = bpl - mode->hdisplay * cpp - 6;
blkeol_duration = (blkeol_pck + 6) / d->mdsi->lanes;
- dev_dbg(d->dev, "blkeol pck: %u, duration: %u\n",
- blkeol_pck, blkeol_duration);
+ dev_dbg(d->dev, "blkeol pck: %u bytes, duration: %u bytes\n",
+ blkeol_pck, blkeol_duration);
if (d->mdsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
/* Set up EOL clock for burst mode */
val = readl(d->regs + DSI_VID_BLKSIZE1);
val |= blkeol_pck << DSI_VID_BLKSIZE1_BLKEOL_PCK_SHIFT;
writel(val, d->regs + DSI_VID_BLKSIZE1);
- writel(blkeol_pck, d->regs + DSI_VID_VCA_SETTING2);
+ writel(blkeol_pck & DSI_VID_VCA_SETTING2_EXACT_BURST_LIMIT_MASK,
+ d->regs + DSI_VID_VCA_SETTING2);
writel(blkeol_duration, d->regs + DSI_VID_PCK_TIME);
writel(blkeol_duration - 6, d->regs + DSI_VID_VCA_SETTING1);
@@ -535,9 +553,11 @@ static void mcde_dsi_setup_video_mode(struct mcde_dsi *d,
/* Maximum line limit */
val = readl(d->regs + DSI_VID_VCA_SETTING2);
+ val &= ~DSI_VID_VCA_SETTING2_MAX_LINE_LIMIT_MASK;
val |= blkline_pck <<
DSI_VID_VCA_SETTING2_EXACT_BURST_LIMIT_SHIFT;
writel(val, d->regs + DSI_VID_VCA_SETTING2);
+ dev_dbg(d->dev, "blkline pck: %u bytes\n", blkline_pck);
/* Put IF1 into video mode */
val = readl(d->regs + DSI_MCTL_MAIN_DATA_CTL);
@@ -699,7 +719,9 @@ static void mcde_dsi_bridge_mode_set(struct drm_bridge *bridge,
lp_freq = d->mdsi->lp_rate;
else
lp_freq = DSI_DEFAULT_LP_FREQ_HZ;
- if (d->mdsi->hs_rate)
+ if (pixel_clock_hz)
+ hs_freq = pixel_clock_hz;
+ else if (d->mdsi->hs_rate)
hs_freq = d->mdsi->hs_rate;
else
hs_freq = DSI_DEFAULT_HS_FREQ_HZ;
--
2.21.0
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