Re: [PATCH v3 1/5] msm/drm/dsi: Round up DSC hdisplay calculation

From: Jessica Zhang
Date: Mon May 22 2023 - 14:03:53 EST




On 5/20/2023 1:07 AM, Marijn Suijten wrote:
On 2023-05-19 14:17:26, Jessica Zhang wrote:
Currently, when compression is enabled, hdisplay is reduced via integer
division. This causes issues for modes where the original hdisplay is
not a multiple of 3.

To fix this, use DIV_ROUND_UP to divide hdisplay.

Reported-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>

This should have been:

Suggested-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>

Fixes: f3a99460406b ("drm/msm/dsi: update hdisplay calculation for dsi_timing_setup")

This hash is not valid (and checkpatch points it out...), as it is your
local commit from the MSM DSC helper methods series. The original issue
was introduced in:

Fixes: 08802f515c3cf ("drm/msm/dsi: Add support for DSC configuration")

Hi Marijn,

Acked.

Thanks,

Jessica Zhang


- Marijn

Signed-off-by: Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>
---
drivers/gpu/drm/msm/dsi/dsi_host.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 9223d7ec5a73..18d38b90eb28 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -952,7 +952,7 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
* pulse width same
*/
h_total -= hdisplay;
- hdisplay = msm_dsc_get_bytes_per_line(msm_host->dsc) / 3;
+ hdisplay = DIV_ROUND_UP(msm_dsc_get_bytes_per_line(msm_host->dsc), 3);
h_total += hdisplay;
ha_end = ha_start + hdisplay;
}

--
2.40.1