[v4,00/25] drm/msm/dpu: Add Concurrent Writeback Support for DPU 10.x+

Message

Jessica Zhang Dec. 17, 2024, 12:43 a.m. UTC

DPU supports a single writeback session running concurrently with primary
display when the CWB mux is configured properly. This series enables
clone mode for DPU driver and adds support for programming the CWB mux
in cases where the hardware has dedicated CWB pingpong blocks. Currently,
the CWB hardware blocks have only been added to the SM8650
hardware catalog and only DSI has been exposed as a possible_clone of WB.

This changes are split into two parts:

The first part of the series will pull in Dmitry's patches to refactor
the DPU resource manager to be based off of CRTC instead of encoder.
This includes some changes (noted in the relevant commits) by me and
Abhinav to fix some issues with getting the global state and refactoring
the CDM allocation to work with Dmitry's changes.

The second part of the series will add support for CWB by doing the
following:

1) Add a DRM helper to detect if the current CRTC state is in clone mode
   and add an "in_clone_mode" entry to the atomic state print
2) Add the CWB mux to the hardware catalog and clarify the pingpong
   block index enum to specifiy which pingpong blocks are dedicated to
   CWB only and which ones are general use pingpong blocks
3) Add CWB as part of the devcoredump
4) Add support for configuring the CWB mux via dpu_hw_cwb ops
5) Add pending flush support for CWB
6) Add support for validating clone mode in the DPU CRTC and setting up
   CWB within the encoder
7) Adjust the encoder trigger flush, trigger start, and kickoff order to
   accomodate clone mode
8) Adjust when the frame done timer is started for clone mode
9) Define the possible clones for DPU encoders so that 

The feature was tested on SM8650 using IGT's kms_writeback test with the
following change [1] and dumping the writeback framebuffer when in clone
mode. I haven't gotten the chance to test it on DP yet, but I've
validated both single and dual LM on DSI.

To test CWB with IGT, you'll need to apply this series [1] and this
driver patch [2]. Run the following command to dump the writeback buffer:

IGT_FRAME_DUMP_PATH=<dump path> FRAME_PNG_FILE_NAME=<file name> \
./build/tests/kms_writeback -d [--run-subtest dump-valid-clones] \

You can also do CRC validation by running this command:

./build/tests/kms_writeback [--run-subtest dump-valid-clones]

[1] https://patchwork.freedesktop.org/series/137933/
[2] https://patchwork.freedesktop.org/series/138284/

---
Changes in v4:
- Rebased onto latest msm-next
- Added kunit tests for framework changes
- Skip valid clone check for encoders that don't have any possible clones set
  (this is to avoid failing kunit tests, specifically the HDMI state helper tests)
- Link to v3: https://lore.kernel.org/r/[e-mail]

Changes in v3:
- Dropped support for CWB on DP connectors for now
- Dropped unnecessary PINGPONG array in *_setup_cwb()
- Add a check to make sure CWB and CDM aren't supported simultaneously
  (Dmitry)
- Document cwb_enabled checks in dpu_crtc_get_topology() (Dmitry)
- Moved implementation of drm_crtc_in_clone_mode() to drm_crtc.c (Jani)
- Dropped duplicate error message for reserving CWB resources (Dmitry)
- Added notes in framework changes about posting a separate series to
  add proper KUnit tests (Maxime)
- Added commit message note addressing Sima's comment on handling
  mode_changed (Dmitry)
- Formatting fixes (Dmitry)
- Added proper kerneldocs (Dmitry)
- Renamed dpu_encoder_helper_get_cwb() -> *_get_cwb_mask() (Dmitry)
- Capitalize all instances of "pingpong" in comments (Dmitry)
- Link to v2: https://lore.kernel.org/r/[e-mail]

Changes in v2:
- Moved CWB hardware programming to its own dpu_hw_cwb abstraction
  (Dmitry)
- Reserve and get assigned CWB muxes using RM API and KMS global state
  (Dmitry)
- Dropped requirement to have only one CWB session at a time
- Moved valid clone mode check to DRM framework (Dmitry and Ville)
- Switch to default CWB tap point to LM as the DSPP
- Dropped printing clone mode status in atomic state (Dmitry)
- Call dpu_vbif_clear_errors() before dpu_encoder_kickoff() (Dmitry)
- Squashed setup_input_ctrl() and setup_input_mode() into a single
  dpu_hw_cwb op (Dmitry)
- Moved function comment docs to correct place and fixed wording of
  comments/commit messages (Dmitry)
- Grabbed old CRTC state using proper drm_atomic_state API in
  dpu_crtc_atomic_check() (Dmitry)
- Split HW catalog changes of adding the CWB mux block and changing the
  dedicated CWB pingpong indices into 2 separate commits (Dmitry)
- Moved clearing the dpu_crtc_state.num_mixers to "drm/msm/dpu: fill
  CRTC resources in dpu_crtc.c" (Dmitry)
- Fixed alignment and other formatting issues (Dmitry)
- Link to v1: https://lore.kernel.org/r/[e-mail]

---
Dmitry Baryshkov (4):
      drm/msm/dpu: get rid of struct dpu_rm_requirements
      drm/msm/dpu: switch RM to use crtc_id rather than enc_id for allocation
      drm/msm/dpu: move resource allocation to CRTC
      drm/msm/dpu: fill CRTC resources in dpu_crtc.c

Esha Bharadwaj (3):
      drm/msm/dpu: Add CWB entry to catalog for SM8650
      drm/msm/dpu: add devcoredumps for cwb registers
      drm/msm/dpu: add CWB support to dpu_hw_wb

Jessica Zhang (18):
      drm: add clone mode check for CRTC
      drm/tests: Add test for drm_crtc_in_clone_mode()
      drm: Add valid clones check
      drm/tests: Add test for drm_atomic_helper_check_modeset()
      drm/msm/dpu: Specify dedicated CWB pingpong blocks
      drm/msm/dpu: Add dpu_hw_cwb abstraction for CWB block
      drm/msm/dpu: Add RM support for allocating CWB
      drm/msm/dpu: Add CWB to msm_display_topology
      drm/msm/dpu: Require modeset if clone mode status changes
      drm/msm/dpu: Fail atomic_check if CWB and CDM are enabled
      drm/msm/dpu: Reserve resources for CWB
      drm/msm/dpu: Configure CWB in writeback encoder
      drm/msm/dpu: Support CWB in dpu_hw_ctl
      drm/msm/dpu: Adjust writeback phys encoder setup for CWB
      drm/msm/dpu: Start frame done timer after encoder kickoff
      drm/msm/dpu: Skip trigger flush and start for CWB
      drm/msm/dpu: Reorder encoder kickoff for CWB
      drm/msm/dpu: Set possible clones for all encoders

 drivers/gpu/drm/drm_atomic_helper.c                |  28 ++
 drivers/gpu/drm/drm_crtc.c                         |  20 +
 drivers/gpu/drm/msm/Makefile                       |   1 +
 .../drm/msm/disp/dpu1/catalog/dpu_10_0_sm8650.h    |  29 +-
 .../gpu/drm/msm/disp/dpu1/catalog/dpu_8_1_sm8450.h |   4 +-
 .../drm/msm/disp/dpu1/catalog/dpu_8_4_sa8775p.h    |   4 +-
 .../gpu/drm/msm/disp/dpu1/catalog/dpu_9_0_sm8550.h |   4 +-
 .../drm/msm/disp/dpu1/catalog/dpu_9_2_x1e80100.h   |   4 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c           | 208 ++++++++-
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c        | 463 ++++++++++++---------
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h        |  14 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h   |   7 +-
 .../gpu/drm/msm/disp/dpu1/dpu_encoder_phys_wb.c    |  16 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h     |  13 +
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c         |  30 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h         |  15 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_cwb.c         |  73 ++++
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_cwb.h         |  70 ++++
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h        |  15 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_wb.c          |   4 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c            |  12 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h            |  13 +-
 drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c             | 361 +++++++++-------
 drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h             |  13 +-
 drivers/gpu/drm/tests/drm_atomic_state_test.c      | 133 +++++-
 include/drm/drm_crtc.h                             |   2 +-
 26 files changed, 1172 insertions(+), 384 deletions(-)
---
base-commit: 86313a9cd152330c634b25d826a281c6a002eb77
change-id: 20240618-concurrent-wb-97d62387f952
prerequisite-change-id: 20241209-abhinavk-modeset-fix-74864f1de08d:v3
prerequisite-patch-id: a197a0cd4647cb189ea20a96583ea78d0c98b638
prerequisite-patch-id: 112c8f1795cbed989beb02b72561854c0ccd59dd

Best regards,