On 14/06/2023 23:39, Abhinav Kumar wrote:
On 6/14/2023 12:54 PM, Abhinav Kumar wrote:
On 6/14/2023 12:35 PM, Abhinav Kumar wrote:
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.
I looked at the internal docs and also this change. This change is
incorrect because this will try to enable widebus for DPU >= 5.0 and DSI
>= 2.5
That was not the intended right condition as thats not what the docs say.
We should enable for DPU >= 7.0 and DSI >= 2.5
Is there any combination where this compatibility is broken? That would
be the strange thing for me ( not DPU 5.0 and DSI 2.5 as that was
incorrect)
Part of this confusion is because of catalog macro re-use again.
This series is a good candidate and infact I think we should only do
core_revision based check on DPU and DSI to avoid bringing the catalog
mess into this.
I have just a single request here: can we please have the same approach
for both DSI and DP? I don't mind changing DP code if it makes it
better. If you don't have better reasons, I like the idea of DSI/DP
dictating whether wide bus should be used on the particular interface.
It allows us to handle possible errata or corner cases there. Another
option would be to make DPU tell DSI / DP whether the wide bus is
enabled or not, but I'd say, this is slightly worse solution.
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.
Missed this response. That seems strange.
This series was tested on SM8350 HDK with a command mode panel.
We will fix the DPU-DSI handshake and post a v2 but your issue needs
investigation in parallel.
So another bug to track that would be great.
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.
I have clarified this above. Its not strange but appeared strange
because we were checking wrong conditions.
- Marijn
--
With best wishes
Dmitry
