Re: [PATCH 1/3] drm/msm/dpu: Add DPU_INTF_DATABUS_WIDEN feature flag for DPU >= 5.0

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





On 6/14/2023 5:23 AM, Marijn Suijten wrote:
On 2023-06-14 15:01:59, Dmitry Baryshkov wrote:
On 14/06/2023 14:42, Marijn Suijten wrote:
On 2023-06-13 18:57:11, Jessica Zhang wrote:
DPU 5.x+ supports a databus widen mode that allows more data to be sent
per pclk. Enable this feature flag on all relevant chipsets.

Signed-off-by: Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>
---
   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c | 3 ++-
   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h | 2 ++
   2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c
index 36ba3f58dcdf..0be7bf0bfc41 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c
@@ -103,7 +103,8 @@
   	(BIT(DPU_INTF_INPUT_CTRL) | \
   	 BIT(DPU_INTF_TE) | \
   	 BIT(DPU_INTF_STATUS_SUPPORTED) | \
-	 BIT(DPU_DATA_HCTL_EN))
+	 BIT(DPU_DATA_HCTL_EN) | \
+	 BIT(DPU_INTF_DATABUS_WIDEN))

This doesn't work.  DPU 5.0.0 is SM8150, which has DSI 6G 2.3.  In the
last patch for DSI you state and enable widebus for DSI 6G 2.5+ only,
meaning DPU and DSI are now desynced, and the output is completely
corrupted.

Tested this on SM8350 which actually has DSI 2.5, and it is also
corrupted with this series so something else on this series might be
broken.

Is the bound in dsi_host wrong, or do DPU and DSI need to communicate
when widebus will be enabled, based on DPU && DSI supporting it?

I'd prefer to follow the second approach, as we did for DP. DPU asks the
actual video output driver if widebus is to be enabled.


I was afraid of this. This series was made on an assumption that the DPU version of widebus and DSI version of widebus would be compatible but looks like already SM8150 is an outlier.

Yes, I think we have to go with second approach.

DPU queries DSI if it supports widebus and enables it.

Thanks for your responses. We will post a v2.

Doesn't it seem very strange that DPU 5.x+ comes with a widebus feature,
but the DSI does not until two revisions later?  Or is this available on
every interface, but only for a different (probably DP) encoder block?


Yes its strange.

- Marijn



[Index of Archives]     [Linux DRI Users]     [Linux Intel Graphics]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux