drm/i915/fbc: Streamline frontbuffer busy bits handling

If the frontbuffer bits say this fbc instance isn't affected just
skip the whole thing.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220315140001.1172-3-ville.syrjala@linux.intel.com
Reviewed-by: Mika Kahola <mika.kahola@intel.com>

diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
index 948f6bfe22331c7e0503c475c87217c1a23dbb0c..f22d727949682e6637c04a90aeb81c444c738122 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_fbc.c
+++ b/drivers/gpu/drm/i915/display/intel_fbc.c
@@ -1273,6 +1273,7 @@ static void __intel_fbc_disable(struct intel_fbc *fbc)
        __intel_fbc_cleanup_cfb(fbc);
 
        fbc->state.plane = NULL;
+       fbc->busy_bits = 0;
 }
 
 static void __intel_fbc_post_update(struct intel_fbc *fbc)
@@ -1328,11 +1329,14 @@ static void __intel_fbc_invalidate(struct intel_fbc *fbc,
 
        mutex_lock(&fbc->lock);
 
-       fbc->busy_bits |= intel_fbc_get_frontbuffer_bit(fbc) & frontbuffer_bits;
+       frontbuffer_bits &= intel_fbc_get_frontbuffer_bit(fbc);
+       if (!frontbuffer_bits)
+               goto out;
 
-       if (fbc->state.plane && fbc->busy_bits)
-               intel_fbc_deactivate(fbc, "frontbuffer write");
+       fbc->busy_bits |= frontbuffer_bits;
+       intel_fbc_deactivate(fbc, "frontbuffer write");
 
+out:
        mutex_unlock(&fbc->lock);
 }
 
@@ -1354,18 +1358,22 @@ static void __intel_fbc_flush(struct intel_fbc *fbc,
 {
        mutex_lock(&fbc->lock);
 
+       frontbuffer_bits &= intel_fbc_get_frontbuffer_bit(fbc);
+       if (!frontbuffer_bits)
+               goto out;
+
        fbc->busy_bits &= ~frontbuffer_bits;
 
        if (origin == ORIGIN_FLIP || origin == ORIGIN_CURSOR_UPDATE)
                goto out;
 
-       if (!fbc->busy_bits && fbc->state.plane &&
-           (frontbuffer_bits & intel_fbc_get_frontbuffer_bit(fbc))) {
-               if (fbc->active)
-                       intel_fbc_nuke(fbc);
-               else if (!fbc->flip_pending)
-                       __intel_fbc_post_update(fbc);
-       }
+       if (fbc->busy_bits)
+               goto out;
+
+       if (fbc->active)
+               intel_fbc_nuke(fbc);
+       else if (!fbc->flip_pending)
+               __intel_fbc_post_update(fbc);
 
 out:
        mutex_unlock(&fbc->lock);