On 4/30/2022 11:58 AM, Marijn Suijten wrote:
On 2022-04-30 20:55:33, Dmitry Baryshkov wrote:
The downstream uses read-modify-write for updating command mode
compression registers. Let's follow this approach. This also fixes the
following warning:
drivers/gpu/drm/msm/dsi/dsi_host.c:918:23: warning: variable 'reg_ctrl' set but not used [-Wunused-but-set-variable]
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Fixes: 08802f515c3c ("drm/msm/dsi: Add support for DSC configuration")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
I pointed this out in review multiple times, so you'll obviously get my:
Reviewed-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>
(But are you sure there's nothing else to clear in the 1st CTRL
register, only the lowest 16 bits? That should mean `reg` never
contains anything in 0xffff0000)
The top 16 bits contain information for stream 1.
Stream 1 is unused. And whatever is the reset value we should retain that.
So this patch is correct.
However, this seems to indicate that the DSC patch series has been
approved and merged somehow??
---
Changes since v1:
- Fix c&p error and apply mask clear to reg_ctrl2 instead of reg_ctrl
(Abhinav)
---
drivers/gpu/drm/msm/dsi/dsi_host.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index c983698d1384..a95d5df52653 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -961,10 +961,13 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod
reg_ctrl = dsi_read(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL);
reg_ctrl2 = dsi_read(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL2);
+ reg_ctrl &= ~0xffff;
reg_ctrl |= reg;
+
+ reg_ctrl2 &= ~DSI_COMMAND_COMPRESSION_MODE_CTRL2_STREAM0_SLICE_WIDTH__MASK;
reg_ctrl2 |= DSI_COMMAND_COMPRESSION_MODE_CTRL2_STREAM0_SLICE_WIDTH(bytes_in_slice);
- dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL, reg);
+ dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL, reg_ctrl);
dsi_write(msm_host, REG_DSI_COMMAND_COMPRESSION_MODE_CTRL2, reg_ctrl2);
} else {
dsi_write(msm_host, REG_DSI_VIDEO_COMPRESSION_MODE_CTRL, reg);
--
2.35.1
