Re: [PATCH 0/7] Prepare GVT for display modularization

["Nautiyal, Ankit K" <ankit.k.nautiyal@intel.com>]

On 12/18/2025 4:27 PM, Jani Nikula wrote:
> On Thu, 18 Dec 2025, Ankit Nautiyal <ankit.k.nautiyal@intel.com> wrote:
>> GVT currently relies on display internals through register macros and
>> helpers like for_each_pipe(). This tight coupling makes modularization
>> difficult because GVT should not access struct intel_display directly.
>> Add an API for GVT code to expose DISPLAY_RUNTIME_INFO()->pipe_mask.
>> This series introduces changes to make GVT independent of display internals
>> while keeping existing macros usable:
>>
>> - Abstract offset calculations in display using
>>    INTEL_DISPLAY_DEVICE_*_OFFSET() macros.
>> - Add APIs for GVT to compute offsets and pipe mask via functions.
>> - Update GVT to use these APIs by overriding helper macros and
>>    for_each_pipe().
> Oh, this doesn't handle intel_gvt_mmio_table.c, which is part of i915.
>
> That can be a follow-up, I guess, but still needs to be addressed.

Ohh yeah, I had looked into it earlier, but completely missed it after I 
returned from my leave.

Will look into that after this series.

Regards,

Ankit

> BR,
> Jani.
>
>> Rev2:
>> - Remove conflicting headers and get rid of #ifdefs/#undefs in last
>>    patch.
>> - Wrap macro arguments in paranthesis.
>> - Rename for_each_pipe to gvt_for_each_pipe.
>>
>> PS: I have not yet addressed the question about whether we need to start
>>      using _MMIO_TRANS2() instead of_MMIO_PIPE2() in TRANSCONF() macro.
>>      That likely needs a separate patch and discussion.
>>      For now, I have kept the patch#4 to deal with the
>>      -Werror=enum-conversion:
>>       - drm/i915/gvt/display_helpers: Cast argument to enum pipe for
>>         pipe-offset macro
>>
>> Ankit Nautiyal (7):
>>    drm/i915/display: Abstract pipe/trans/cursor offset calculation
>>    drm/i915/display: Add APIs to be used by gvt to get the register
>>      offsets
>>    drm/i915/gvt: Add header to use display offset functions in macros
>>    drm/i915/gvt/display_helpers: Cast argument to enum pipe for
>>      pipe-offset macro
>>    drm/i915/gvt: Change for_each_pipe to use pipe_valid API
>>    drm/i915/gvt: Use the appropriate header for the DPLL macro
>>    drm/i915/gvt/display_helper: Get rid of #ifdef/#undefs
>>
>>   drivers/gpu/drm/i915/Makefile                 |  1 +
>>   .../drm/i915/display/intel_display_device.h   | 17 +++++++
>>   .../drm/i915/display/intel_display_limits.c   |  0
>>   .../drm/i915/display/intel_display_reg_defs.h | 15 ++-----
>>   drivers/gpu/drm/i915/display/intel_gvt_api.c  | 45 +++++++++++++++++++
>>   drivers/gpu/drm/i915/display/intel_gvt_api.h  | 21 +++++++++
>>   drivers/gpu/drm/i915/gvt/cmd_parser.c         |  2 +-
>>   drivers/gpu/drm/i915/gvt/display.c            |  9 ++--
>>   drivers/gpu/drm/i915/gvt/display_helpers.h    | 27 +++++++++++
>>   drivers/gpu/drm/i915/gvt/fb_decoder.c         |  2 +-
>>   drivers/gpu/drm/i915/gvt/handlers.c           |  2 +-
>>   11 files changed, 123 insertions(+), 18 deletions(-)
>>   create mode 100644 drivers/gpu/drm/i915/display/intel_display_limits.c
>>   create mode 100644 drivers/gpu/drm/i915/display/intel_gvt_api.c
>>   create mode 100644 drivers/gpu/drm/i915/display/intel_gvt_api.h
>>   create mode 100644 drivers/gpu/drm/i915/gvt/display_helpers.h