Soliciting DRM feedback on latest DC rework

[Harry Wentland]

Hi all,

Over the last few months we (mostly Andrey and myself) have taken and 
addressed some of the feedback received from December's DC RFC. A lot of 
our work so far centers around atomic. We were able to take a whole 
bunch of the areas where we rolled our own solution and use DRM atomic 
helpers instead.

You can find our most recent drm-next based tree at 
https://cgit.freedesktop.org/~hwentland/linux/log/?h=dc-drm-next-atomic-wip

An outline of the changes with commit hashes from that tree are listed 
below. They aren't necessarily in order but are grouped by functionality.

I would like to solicit input on the changes and the current state of 
amd/display in general.

I'm on IRC every weekday from 9-5 eastern time, sometimes at other 
hours. Feel free to ask questions, discuss, leave comments. Let me know 
if there's anything else I can do to facilitate review.

We know there's more work to be done but would much rather prioritize 
that work based on community feedback than merely our own impressions.

We haven't finished plumbing drm types to the dc types yet, and there 
are still a bunch of other things in progress.  We are not looking to 
re-hash the previous discussion, but rather we'd like some feedback on 
our work so far.

The list of changes (trimmed commit tags):

== Use common helpers for pageflip ==
144da239b047 Use pflip prepare and submit parts (v2)
ff7ac264a9a1 Fix page flip after daniel's acquire_ctx change


== implement atomic_get_properties ==
cf4a84df7189 Fallback on legacy properties in atomic_get_properties
01f96706b6ca get_atomic_property missing for drm_connector_funcs


== Use common helpers for gamma ==
3f547d7098de Use atomic helpers for gamma


== Use atomic helpers for commit ==
41831f55bd58 Refactor atomic commit implementation. (v2)
6c67dd3c5cd5 Refactor headless to use atomic commit.
eb22ef1ecb16 Remove page_fleep_needed function.


== Use atomic helpers for S3 ==
5a6ae6f76249 Switch to DRM helpers in s3.


== Simmplify mapping between DRM and DC objects ==
84a3ee023b9b Remove get_connector_for_link.
6d8978a98b40 Remove get_connector_for_sink.


== Use DRM EDID read instead of DC ==
566969dacfad Fix i2c write flag.
527c3699ff3c Refactor edid read.
5ac51023d275 Fix missing irq refactor causing potential i2c race


== Save DC validate_ctx in atomic_check and use in commit ==
8c194d8e4ee9 pull commit_surfaces out of atomic_commit into helper function
27eef98b38c8 Return context from validate_context
ca3ee10e915b Add DM global atomic state
8ba1ca856532 Hook dm private state into atomic_check
10160455ac6d Add correct retain/release for objs in dm_atomic_state
0f1b2e2aecbb Commit validation set from state
258e6a91fc61 Add validate_context to atomic_state
64f569b5df20 Use validate_context from atomic_check in commit


== Start multi-plane implementation ==
601ff4e70b7c decouple per-crtc-plane model
a0b859a0b114 Fix cleanup in amdgpu_dm_initialize_drm_device
ee02010d7a82 update plane functionalities
3b7345fd1abb Allow planes on all crtcs
d9cf37462156 initialize YUV plane capabilities
248f06b2613e Universal cursor plane hook-up.


== Minor cleanups ==
d99bf02cb8fc Rename atomic_commit parameter.
f15fb9726502 Use amdgpu mode funcs statically
d3e37fa70643 Remove unused define from amdgpu_dm_types
80a38ad58125 Add lock around updating freesync property
8c7f16853824 Use new drm_dp_find_vcpi_slots to compute slots

Regards,
Harry