[PATCH v9 0/8] Introduce MSM-specific DSC helpers

Jessica Zhang quic_jesszhan at quicinc.com
Wed May 10 22:54:40 UTC 2023


There are some overlap in calculations for MSM-specific DSC variables
between DP and DSI. In addition, the calculations for initial_scale_value
and det_thresh_flatness that are defined within the DSC 1.2 specifications,
but aren't yet included in drm_dsc_helper.c.

This series moves these calculations to a shared msm_dsc_helper.c file and
defines drm_dsc_helper methods for initial_scale_value and
det_thresh_flatness.

Note: For now, the MSM specific helper methods are only called for the DSI
path, but will called for DP once DSC 1.2 support for DP has been added.

Depends on: "drm/i915: move DSC RC tables to drm_dsc_helper.c" [1]

[1] https://patchwork.freedesktop.org/series/114472/

---
Changes in v9:
- Fixed incorrect math for msm_dsc_get_bytes_per_line()
- Link to v8: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v8-0-2c9b2bb1209c@quicinc.com

Changes in v8:
- *_bytes_per_soft_slice --> *_bytes_per_slice
- Fixed comment doc formatting for MSM DSC helpers
- Use slice_chunk_size in msm_dsc_get_bytes_per_line calculation
- Reworded "drm/msm/dpu: Use DRM DSC helper for det_thresh_flatness"
  commit title for clarity
- Picked up "Reviewed-by" tags
- Added duplicate Signed-off-by tag to "drm/display/dsc: Add flatness
  and initial scale value calculations" to reflect patch history
- Link to v7: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v7-0-df48a2c54421@quicinc.com

Changes in v7:
- Renamed msm_dsc_get_pclk_per_intf to msm_dsc_get_bytes_per_line
- Removed duplicate msm_dsc_get_dce_bytes_per_line
- Reworded commit message for "drm/msm/dpu: Use DRM DSC helper for
  det_thresh_flatness"
- Dropped slice_per_pkt change (it will be included in the later
  "Add DSC v1.2 Support for DSI" series)
- Picked up "drm/display/dsc: Add flatness and initial scale value
  calculations" and "drm/display/dsc: add helper to set semi-const
  parameters", which were dropped from "drm/i915: move DSC RC tables to
  drm_dsc_helper.c" series
- Picked up "Reviewed-by" tags
- Removed changelog in individual patches
- Link to v6: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v6-0-cb7f59f0f7fb@quicinc.com

Changes in v6:
- Documented return values for MSM DSC helpers
- Fixed dependency issue in msm_dsc_helper.c
- Link to v5: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v5-0-0108401d7886@quicinc.com

Changes in v5:
- Added extra line at end of msm_dsc_helper.h
- Simplified msm_dsc_get_bytes_per_soft_slice() math
- Simplified and inlined msm_dsc_get_pclk_per_intf() math
- "Fix calculations pkt_per_line" --> "... Fix calculation for pkt_per_line"
- Split dsc->slice_width check into a separate patch
- Picked up Dmitry's msm/dsi patch ("drm/msm/dsi: use new helpers for
  DSC setup")
- Removed unused headers in MSM DSC helper files
- Picked up Reviewed-by tags
- Link to v4: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v4-0-1b79c78b30d7@quicinc.com

Changes in v4:
- Changed msm_dsc_get_uncompressed_pclk_per_intf to msm_dsc_get_pclk_per_intf
- Moved pclk_per_intf calculation for dsi_timing_setup to `if
  (msm_host->dsc)` block
- Link to v3: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v3-0-6bec0d277a83@quicinc.com

Changes in v3:
- Dropped src_bpp parameter from all methods -- src_bpp can be
  calculated as dsc->bits_per_component * 3- Cleaned up unused parameters
- Dropped intf_width parameter from get_bytes_per_soft_slice()
- Moved dsc->bits_per_component to numerator calculation in
  get_bytes_per_soft_slice()
- Made get_bytes_per_soft_slice() a public method (this will be called
  later to help calculate DP pclk params)- Added comment documentation to
  MSM DSC helpers
- Renamed msm_dsc_get_uncompressed_pclk_per_line to
  *_get_uncompressed_pclk_per_intf()
- Removed dsc->slice_width check from msm_dsc_get_uncompressed_pclk_per_intf()
- Added documentation in comments
- Moved extra_eol_bytes math out of msm_dsc_get_eol_byte_num()
- Renamed msm_dsc_get_eol_byte_num to *_get_bytes_per_intf.
- Reworded slice_last_group_size calculation to `(dsc->slice_width + 2) % 3`
- Used MSM DSC helper to calculate total_bytes_per_intf
- Initialized hdisplay as uncompressed pclk per line at the beginning of
  dsi_timing_setup as to not break dual DSI calculations
- Added slice_width check to dsi_timing_setup
- Dropped 78c8b81d57d8 ("drm/display/dsc: Add flatness and initial scale
  value calculations") patch as it was absorbed in Dmitry's DSC series [1]
- Split dsi_timing_setup() hdisplay calculation to a separate patch
- Link to v2: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v2-0-3c13ced536b2@quicinc.com

Changes in v2:
- Changed det_thresh_flatness to flatness_det_thresh
- Set initial_scale_value directly in helper
- Moved msm_dsc_helper files to msm/ directory
- Dropped get_comp_ratio() helper
- Used drm_int2fixp() to convert to integers to fp
- Fixed type mismatch issues in MSM DSC helpers
- Changed DSC_BPP macro to drm_dsc_get_bpp_int() helper method
- Style changes to improve readability
- Dropped last division step of msm_dsc_get_pclk_per_line() and changed
  method name accordingly
- Dropped unused bpp variable in msm_dsc_get_dce_bytes_per_line()
- Changed msm_dsc_get_slice_per_intf() to a static inline method
- Split eol_byte_num and pkt_per_line calculation into a separate patch
- Moved pclk_per_line calculation into `if (dsc)` block in
  dsi_timing_setup()
- *_calculate_initial_scale_value --> *_set_initial_scale_value
- Picked up Fixes tags for patches 3/5 and 4/5
- Picked up Reviewed-by for patch 4/5
- Link to v1: https://lore.kernel.org/r/20230329-rfc-msm-dsc-helper-v1-0-f3e479f59b6d@quicinc.com

---
Dmitry Baryshkov (2):
      drm/display/dsc: add helper to set semi-const parameters
      drm/msm/dsi: use DRM DSC helpers for DSC setup

Jessica Zhang (6):
      drm/display/dsc: Add flatness and initial scale value calculations
      drm/msm: Add MSM-specific DSC helper methods
      drm/msm/dpu: Use fixed DRM DSC helper for det_thresh_flatness
      drm/msm/dpu: Fix slice_last_group_size calculation
      drm/msm/dsi: Use MSM and DRM DSC helper methods
      drm/msm/dsi: update hdisplay calculation for dsi_timing_setup

 drivers/gpu/drm/display/drm_dsc_helper.c   | 22 ++++++++++
 drivers/gpu/drm/msm/Makefile               |  1 +
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c |  9 ++--
 drivers/gpu/drm/msm/dsi/dsi_host.c         | 70 ++++++------------------------
 drivers/gpu/drm/msm/msm_dsc_helper.c       | 26 +++++++++++
 drivers/gpu/drm/msm/msm_dsc_helper.h       | 69 +++++++++++++++++++++++++++++
 include/drm/display/drm_dsc_helper.h       | 12 +++++
 7 files changed, 149 insertions(+), 60 deletions(-)
---
base-commit: 5526fe03b40ca1cc72c7b4e97f28d3bbfaa0ded9
change-id: 20230329-rfc-msm-dsc-helper-981a95edfbd0

Best regards,
-- 
Jessica Zhang <quic_jesszhan at quicinc.com>



More information about the dri-devel mailing list