[PATCH v2 1/6] drm/i915: Add the FIRST_CCS() helper

[Andi Shyti]

From: Andi Shyti <andi.shyti at intel.com>

Some GPUs, like DG2, can host more than one CCS engine. Some
workarounds or enablements need to happen only once for all the
engines in the GT—for example, on the engine with the lowest
instance.

The FIRST_CCS() helper first checks if the engine is a Compute
engine, and then whether it's the one with the lowest instance.

Signed-off-by: Andi Shyti <andi.shyti at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 54538b6f85df..5cb501393c4b 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -619,6 +619,9 @@ IS_SUBPLATFORM(const struct drm_i915_private *i915,
 #define CCS_MASK(gt) \
 	ENGINE_INSTANCES_MASK(gt, CCS0, I915_MAX_CCS)
 
+#define FIRST_CCS(e__) \
+	(CCS_MASK(e__->gt) && (__ffs(CCS_MASK(e__->gt)) == e__->instance))
+
 #define HAS_MEDIA_RATIO_MODE(i915) (INTEL_INFO(i915)->has_media_ratio_mode)
 
 /*
-- 
2.47.2