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From: Mohit Dsor <mohit.dsor@oss.qualcomm.com>
To: neil.armstrong@linaro.org
Cc: linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org,
	freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: [REGRESSION] Resolutions broken after "drm/msm: dsi: fix PLL init in bonded mode"
Date: Sun, 26 Apr 2026 03:38:49 +0530	[thread overview]
Message-ID: <ae07cef84AmXK43H@hu-mdsor-hyd.qualcomm.com> (raw)
In-Reply-To: <20251027-topic-sm8x50-fix-dsi-bonded-v1-1-a477cd3f907d@linaro.org>

Hi Neil, all,

We are seeing a regression after:

drm/msm: dsi: fix PLL init in bonded mode
https://lore.kernel.org/r/20251027-topic-sm8x50-fix-dsi-bonded-v1-1-a477cd3f907d@linaro.org

Issue:
- Resolutions are broken after this change. Like if we try to run 720p60 it will be 720p30.
  Even though the byte_clk is set correctly, the bridge is receiving half the byte clock.
  Some divider is getting set which is causing the byte_clk to get half, ultimately fps to
  get half. Some other resolutions may or may not be broken

Reproduction:
- Used QNX RB3Gen2 Core kit with lilliput display and lt9611uxc dsi to hdmi bridge.
- Run 720p60 usecase on hdmi with dsi to hdmi bridge.

Expected behavior:
- Display should support the expected resolutions correctly.

Actual behavior:
- No display on lilliput display.

Additional details:
- Reverting this change locally avoids the issue.

Could you please take a look?

Thanks,
Mohit

  parent reply	other threads:[~2026-04-25 22:08 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-10-27 13:09 [PATCH] drm/msm: dsi: fix PLL init in bonded mode Neil Armstrong
2025-10-27 13:20 ` Dmitry Baryshkov
2025-10-29  0:30 ` Dmitry Baryshkov
2026-04-25 22:08 ` Mohit Dsor [this message]
2026-04-25 22:44   ` [REGRESSION] Resolutions broken after "drm/msm: dsi: fix PLL init in bonded mode" Dmitry Baryshkov
2026-05-04 20:09     ` Mohit Dsor

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