Re: [PATCH v1 12/14] drm/msm/disp/dpu1: revise timing engine programming to work for DSC
From: Dmitry Baryshkov
Date: Tue Jan 24 2023 - 04:11:34 EST
On 23/01/2023 20:24, Kuogee Hsieh wrote:
Current implementation timing engine programming does not consider
compression factors. This patch add consideration of DSC factors
while programming timing engine.
Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
---
.../gpu/drm/msm/disp/dpu1/dpu_encoder_phys_vid.c | 2 +
drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h | 14 ++-
drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.c | 132 +++++++++++++--------
drivers/gpu/drm/msm/disp/dpu1/dpu_hw_intf.h | 10 +-
drivers/gpu/drm/msm/disp/dpu1/dpu_hw_top.h | 6 +-
5 files changed, 110 insertions(+), 54 deletions(-)
[skipped]
@@ -113,82 +124,96 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *ctx,
/* read interface_cfg */
intf_cfg = DPU_REG_READ(c, INTF_CONFIG);
- if (ctx->cap->type == INTF_DP)
+ if (ctx->cap->type == INTF_EDP || ctx->cap->type == INTF_DP)
dp_intf = true;
hsync_period = p->hsync_pulse_width + p->h_back_porch + p->width +
- p->h_front_porch;
+ p->h_front_porch;
vsync_period = p->vsync_pulse_width + p->v_back_porch + p->height +
- p->v_front_porch;
+ p->v_front_porch;
Actually I went on through the history and found the previous
submission, https://patchwork.freedesktop.org/patch/471505/.
Exactly the same piece of code. Did you expect that the comments will be
different this time?
I really hoped that at that time we already went through this. But it
seems I was wrong. That series went through v10 or v12 before being
accepted. And it was just adding wide_bus_en. Back at that time we
lightly discussed that the code will receive compression support. But I
never expected to see the original submission again.
It might sound bad, but could you please find somebody who can do
internal review for you? Good internal review.
That said, I really do not expect to see v2 before the whole series is
reworked, restructured and prepared for the review on your side.
display_v_start = ((p->vsync_pulse_width + p->v_back_porch) *
- hsync_period) + p->hsync_skew;
+ hsync_period) + p->hsync_skew;
display_v_end = ((vsync_period - p->v_front_porch) * hsync_period) +
- p->hsync_skew - 1;
+ p->hsync_skew - 1;
+
+ hsync_ctl = (hsync_period << 16) | p->hsync_pulse_width;
hsync_start_x = p->h_back_porch + p->hsync_pulse_width;
hsync_end_x = hsync_period - p->h_front_porch - 1;
- if (p->width != p->xres) { /* border fill added */
- active_h_start = hsync_start_x;
- active_h_end = active_h_start + p->xres - 1;
- } else {
- active_h_start = 0;
- active_h_end = 0;
- }
-
- if (p->height != p->yres) { /* border fill added */
- active_v_start = display_v_start;
- active_v_end = active_v_start + (p->yres * hsync_period) - 1;
- } else {
- active_v_start = 0;
- active_v_end = 0;
- }
-
- if (active_h_end) {
- active_hctl = (active_h_end << 16) | active_h_start;
- intf_cfg |= INTF_CFG_ACTIVE_H_EN;
- } else {
- active_hctl = 0;
- }
-
- if (active_v_end)
- intf_cfg |= INTF_CFG_ACTIVE_V_EN;
-
- hsync_ctl = (hsync_period << 16) | p->hsync_pulse_width;
- display_hctl = (hsync_end_x << 16) | hsync_start_x;
-
/*
* DATA_HCTL_EN controls data timing which can be different from
* video timing. It is recommended to enable it for all cases, except
* if compression is enabled in 1 pixel per clock mode
*/
+ if (!p->compression_en || p->wide_bus_en)
+ intf_cfg2 |= INTF_CFG2_DATA_HCTL_EN;
+
if (p->wide_bus_en)
- intf_cfg2 |= INTF_CFG2_DATABUS_WIDEN | INTF_CFG2_DATA_HCTL_EN;
+ intf_cfg2 |= INTF_CFG2_DATABUS_WIDEN;
+ /*
+ * If widebus is disabled:
+ * For uncompressed stream, the data is valid for the entire active
+ * window period.
+ * For compressed stream, data is valid for a shorter time period
+ * inside the active window depending on the compression ratio.
+ *
+ * If widebus is enabled:
+ * For uncompressed stream, data is valid for only half the active
+ * window, since the data rate is doubled in this mode.
+ * p->width holds the adjusted width for DP but unadjusted width for DSI
+ * For compressed stream, data validity window needs to be adjusted for
+ * compression ratio and then further halved.
+ */
data_width = p->width;
+ if (p->compression_en) {
+ if (p->wide_bus_en)
+ data_width = DIV_ROUND_UP(p->dce_bytes_per_line, 6);
+ else
+ data_width = DIV_ROUND_UP(p->dce_bytes_per_line, 3);
+ } else if (!dp_intf && p->wide_bus_en) {
+ data_width = p->width >> 1;
+ } else {
+ data_width = p->width;
+ }
+
hsync_data_start_x = hsync_start_x;
hsync_data_end_x = hsync_start_x + data_width - 1;
+ display_hctl = (hsync_end_x << 16) | hsync_start_x;
display_data_hctl = (hsync_data_end_x << 16) | hsync_data_start_x;
if (dp_intf) {
/* DP timing adjustment */
display_v_start += p->hsync_pulse_width + p->h_back_porch;
display_v_end -= p->h_front_porch;
+ }
+
+ intf_cfg |= INTF_CFG_ACTIVE_H_EN;
+ intf_cfg |= INTF_CFG_ACTIVE_V_EN;
+ active_h_start = hsync_start_x;
+ active_h_end = active_h_start + p->xres - 1;
+ active_v_start = display_v_start;
+ active_v_end = active_v_start + (p->yres * hsync_period) - 1;
- active_h_start = hsync_start_x;
- active_h_end = active_h_start + p->xres - 1;
- active_v_start = display_v_start;
- active_v_end = active_v_start + (p->yres * hsync_period) - 1;
+ active_hctl = (active_h_end << 16) | active_h_start;
- active_hctl = (active_h_end << 16) | active_h_start;
+ if (dp_intf) {
display_hctl = active_hctl;
- intf_cfg |= INTF_CFG_ACTIVE_H_EN | INTF_CFG_ACTIVE_V_EN;
+ if (p->compression_en) {
+ active_data_hctl = (hsync_start_x + p->extra_dto_cycles) << 16;
+ active_data_hctl += hsync_start_x;
+
+ display_data_hctl = active_data_hctl;
+ }
}
+ _check_and_set_comp_bit(ctx, p->dsc_4hs_merge, p->compression_en, &intf_cfg2);
+
den_polarity = 0;
if (ctx->cap->type == INTF_HDMI) {
hsync_polarity = p->yres >= 720 ? 0 : 1;
@@ -202,7 +227,7 @@ static void dpu_hw_intf_setup_timing_engine(struct dpu_hw_intf *ctx,
--
With best wishes
Dmitry