[PATCH v3 6/6] drm/msm/dsi: support DSC configurations with slice_per_pkt > 1

From: Jun Nie
Date: Wed Apr 03 2024 - 05:15:22 EST


From: Jonathan Marek <jonathan@xxxxxxxx>

Support slice_per_pkt in msm driver.

Note that the removed "pkt_per_line = slice_per_intf * slice_per_pkt"
comment is incorrect.

Also trim the code to simplify the dsc reference.

Signed-off-by: Jonathan Marek <jonathan@xxxxxxxx>
Signed-off-by: Jun Nie <jun.nie@xxxxxxxxxx>
---
drivers/gpu/drm/msm/dsi/dsi_host.c | 35 ++++++++++++++---------------------
1 file changed, 14 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index b0507a42ee6a..0c6f40dbd25c 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -866,17 +866,10 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
slice_per_intf = msm_dsc_get_slices_per_intf(dsc, hdisplay);

total_bytes_per_intf = dsc->slice_chunk_size * slice_per_intf;
- bytes_per_pkt = dsc->slice_chunk_size; /* * slice_per_pkt; */
-
+ bytes_per_pkt = dsc->slice_chunk_size * dsc->slice_per_pkt;
eol_byte_num = total_bytes_per_intf % 3;

- /*
- * Typically, pkt_per_line = slice_per_intf * slice_per_pkt.
- *
- * Since the current driver only supports slice_per_pkt = 1,
- * pkt_per_line will be equal to slice per intf for now.
- */
- pkt_per_line = slice_per_intf;
+ pkt_per_line = slice_per_intf / dsc->slice_per_pkt;

if (is_cmd_mode) /* packet data type */
reg = DSI_COMMAND_COMPRESSION_MODE_CTRL_STREAM0_DATATYPE(MIPI_DSI_DCS_LONG_WRITE);
@@ -916,6 +909,7 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
{
struct drm_display_mode *mode = msm_host->mode;
+ struct drm_dsc_config *dsc = msm_host->dsc;
u32 hs_start = 0, vs_start = 0; /* take sync start as 0 */
u32 h_total = mode->htotal;
u32 v_total = mode->vtotal;
@@ -947,8 +941,7 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
hdisplay /= 2;
}

- if (msm_host->dsc) {
- struct drm_dsc_config *dsc = msm_host->dsc;
+ if (dsc) {
u32 bytes_per_pclk;

/* update dsc params with timing params */
@@ -988,14 +981,14 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
else
bytes_per_pclk = 3;

- hdisplay = DIV_ROUND_UP(msm_dsc_get_bytes_per_line(msm_host->dsc), bytes_per_pclk);
+ hdisplay = DIV_ROUND_UP(msm_dsc_get_bytes_per_line(dsc), bytes_per_pclk);

h_total += hdisplay;
ha_end = ha_start + hdisplay;
}

if (msm_host->mode_flags & MIPI_DSI_MODE_VIDEO) {
- if (msm_host->dsc)
+ if (dsc)
dsi_update_dsc_timing(msm_host, false, mode->hdisplay);

dsi_write(msm_host, REG_DSI_ACTIVE_H,
@@ -1016,21 +1009,17 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
DSI_ACTIVE_VSYNC_VPOS_START(vs_start) |
DSI_ACTIVE_VSYNC_VPOS_END(vs_end));
} else { /* command mode */
- if (msm_host->dsc)
+ if (dsc)
dsi_update_dsc_timing(msm_host, true, mode->hdisplay);

/* image data and 1 byte write_memory_start cmd */
- if (!msm_host->dsc)
+ if (!dsc)
wc = hdisplay * mipi_dsi_pixel_format_to_bpp(msm_host->format) / 8 + 1;
else
/*
* When DSC is enabled, WC = slice_chunk_size * slice_per_pkt + 1.
- * Currently, the driver only supports default value of slice_per_pkt = 1
- *
- * TODO: Expand mipi_dsi_device struct to hold slice_per_pkt info
- * and adjust DSC math to account for slice_per_pkt.
*/
- wc = msm_host->dsc->slice_chunk_size + 1;
+ wc = dsc->slice_chunk_size * dsc->slice_per_pkt + 1;

dsi_write(msm_host, REG_DSI_CMD_MDP_STREAM0_CTRL,
DSI_CMD_MDP_STREAM0_CTRL_WORD_COUNT(wc) |
@@ -1657,8 +1646,12 @@ static int dsi_host_attach(struct mipi_dsi_host *host,
msm_host->lanes = dsi->lanes;
msm_host->format = dsi->format;
msm_host->mode_flags = dsi->mode_flags;
- if (dsi->dsc)
+ if (dsi->dsc) {
msm_host->dsc = dsi->dsc;
+ /* for backwards compatibility, assume 1 if not set */
+ if (!dsi->dsc->slice_per_pkt)
+ dsi->dsc->slice_per_pkt = 1;
+ }

/* Some gpios defined in panel DT need to be controlled by host */
ret = dsi_host_init_panel_gpios(msm_host, &dsi->dev);

--
2.34.1