CVS commit: src/sys/external/bsd/drm2/dist/drm/i915/display

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Sun Dec 19 12:28:55 UTC 2021

Modified Files:
        src/sys/external/bsd/drm2/dist/drm/i915/display: intel_display.c

Log Message:
i915: Backport fix for locking-against-self on attach.

commit d1b2828af0cc414356c18d7814b83ba33b472054
Author: Ville Syrjälä <ville.syrjala%linux.intel.com@localhost>
Date:   Wed Jan 22 22:43:29 2020 +0200

    drm/i915: Fix modeset locks in sanitize_watermarks()

    We've added more internal things that use modeset locks and
    thus we need to be prepared for intel_atomic_check() grabbing
    more locks than what our initial drm_modeset_lock_all_ctx()
    took. So we're missing the backoff handling here.

    Also drm_atomic_helper_duplicate_state() works against us
    by clearing state->acquire_ctx in anticipation of
    drm_atomic_helper_commit_duplicated_state() being used to
    commit the state.

    We could probably just reset acquire_ctx back, but instead
    let's just rewrite the whole thing without using either of
    those "helpers". There's also no need to add any connectors
    to the state here since we just want the new watermarks
    which don't depend on connectors.

    Cc: Chris Wilson <chris%chris-wilson.co.uk@localhost>
    Signed-off-by: Ville Syrjälä <ville.syrjala%linux.intel.com@localhost>
    Link: https://patchwork.freedesktop.org/patch/msgid/20200122204329.2477-1-ville.syrjala%linux.intel.com@localhost
    Reviewed-by: Chris Wilson <chris%chris-wilson.co.uk@localhost>


To generate a diff of this commit:
cvs rdiff -u -r1.9 -r1.10 \
    src/sys/external/bsd/drm2/dist/drm/i915/display/intel_display.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.