On 27/06/2023 23:31, Jessica Zhang wrote:
During a frame transfer in command mode, there could be frequent
LP11 <-> HS transitions when multiple DCS commands are sent mid-frame or
if the DSI controller is running on slow clock and is throttled. To
minimize frame latency due to these transitions, it is recommended to
send the frame in a single burst.
This feature is supported for DSI 6G 1.3 and above, thus enable burst
mode if supported.
Signed-off-by: Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>
---
Changes in v2:
- Moved MDP_CTRL2 register setting to dsi_ctrl_config() (Dmitry/Marijn)
- Read previous value of MDP_CTRL2 register before writing to it
(Dmitry)
- Link to v1: https://lore.kernel.org/r/20230608-b4-add-burst-mode-v1-1-55dfbcfada55@xxxxxxxxxxx
---
drivers/gpu/drm/msm/dsi/dsi_host.c | 7 +++++++
1 file changed, 7 insertions(+)
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 3f6dfb4f9d5a..cdb404885f3c 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -752,6 +752,13 @@ static void dsi_ctrl_enable(struct msm_dsi_host *msm_host,
/* Always insert DCS command */
data |= DSI_CMD_CFG1_INSERT_DCS_COMMAND;
dsi_write(msm_host, REG_DSI_CMD_CFG1, data);
+
+ if (msm_host->cfg_hnd->major == MSM_DSI_VER_MAJOR_6G &&
+ msm_host->cfg_hnd->minor >= MSM_DSI_6G_VER_MINOR_V1_3) {
Nit: please intent in future to the same level (vim: "set cino=(0").
+ data = dsi_read(msm_host, REG_DSI_CMD_MODE_MDP_CTRL2);
+ data |= DSI_CMD_MODE_MDP_CTRL2_BURST_MODE;
+ dsi_write(msm_host, REG_DSI_CMD_MODE_MDP_CTRL2, data);
+ }
}
dsi_write(msm_host, REG_DSI_CMD_DMA_CTRL,
---
base-commit: a0364260213c96f6817f7e85cdce293cb743460f
change-id: 20230608-b4-add-burst-mode-a5bb144069fa
Best regards,
--
With best wishes
Dmitry
