Re: [RFC PATCH 5/7] drm/msm/dpu: Document and enable TEAR interrupts on DSI interfaces

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

 





On 4/17/2023 12:41 PM, Marijn Suijten wrote:
On 2023-02-14 09:54:57, Abhinav Kumar wrote:
[..]
Just wondering, how were the lengths calculated for the INTF blocks?
The values in general seem a little off to me.

These (for MSM8998) have been taken from downstream specifically; my
series starts using INTF_STATUS at 0x26C which conveniently is the
register right after 0x268, matching the fact that INTF TE and these
registers weren't supported/available yet on MSM8998.

For example, I'm looking downstream and it seems to me that the length
for the INTF_0 on MSM8998 should be 0x280. Similarly for SC7280, I'm
seeing that length for INTF + tearcheck should be 0x2c4.

There are many different downstream sources and tags with seemingly
conflicting/confusing information.  For v2 [2] I've picked the highest
register used by the driver which is INTF_TEAR_AUTOREFRESH_CONFIG at
0x2B4 (but there might always be more registers that don't need to be
poked at by the driver, but contain magic debug information and the
like... those would be useful to capture in the dump going forward).

[2]: https://github.com/SoMainline/linux/commit/2bbc609dd28aa0bd0a2dede20163e521912d0072


Not entirely correct.TEAR_AUTOREFRESH_STATUS is at 0x2c0 for sm8350 and
sm8450 as well so 0x2b4 is a bit short. DPU code uses autorefresh status
today.Esp after your changes it will use the autorefresh status from
intf te which is at offset 0x2c0

Revisiting this, I don't see current DPU code nor downstream 5.4 / 5.10
SDE techpack on some of my checkouts use this register, only
INTF_TEAR_AUTOREFRESH_CONFIG at 0x2b4..0x2b7.  Am I missing something
critical here?


Wow, I lost context since its been months since your last response.

But, I refreshed some of it. You are right, we use the status bits present in the INTF_TEAR_AUTOREFRESH_CONFIG and INTF_TEAR_ AUTOREFRESH_STATUS is unused.

I got confused between the status bit present in the two registers as both relate to autorefresh.

But, the offset of of INTF_TEAR_ AUTOREFRESH_STATUS is still at 0x2c0 as i wrote before so 0x2c4 is the accurate length of this block.

And yes, all the blk lengths should be accurate now in the hw catalog after the rework and reviews of that rework.

We have discussed INTF lengths in [1]. The current understanding of the
block lengths can be found at [2]. Please comment there if any of the
fixed lengths sounds incorrect to you.

[1] https://patchwork.freedesktop.org/patch/522187/
[2] https://patchwork.freedesktop.org/patch/522227/

[skipped the rest]


Please correct my understanding here, it was agreed to fix intf blocks
to 0x2c4 here https://patchwork.freedesktop.org/patch/522227/ but I dont
see this was merged?

It was agreed to first land INTF_TE and then add the higher addresses

Seems like it, at least if I interpret [3] correctly.  My series adds a
new define that will hardcode _len to 0x2B8 for now, and Dmitry/Konrad
can later extend it to whatever is stated by the correct downstream
source.


Like mentioned above it should be 0x2c0 for intf block.

If you face any conflicting information in downstream code, you can
always check with me on IRC.

Ack, it looks like others landed these changes for me now via the
catalog rework, so I have just rebased and kept the lengths in.

- 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