From: jsg <jsg@openbsd.org>
Date: Thu, 11 Apr 2024 03:35:18 +0000 (+0000)
Subject: drm/i915/gt: Do not generate the command streamer for all the CCS
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=e029de381abb71f24eaa05e7b7b974a1bb98886e;p=openbsd

drm/i915/gt: Do not generate the command streamer for all the CCS

From Andi Shyti
726ff623869ddc3de887d99296cac3c849061b21 in linux-6.6.y/6.6.26
ea315f98e5d6d3191b74beb0c3e5fc16081d517c in mainline linux
---

diff --git a/sys/dev/pci/drm/i915/gt/intel_engine_cs.c b/sys/dev/pci/drm/i915/gt/intel_engine_cs.c
index 8dab7b76fc6..32506b6b2ab 100644
--- a/sys/dev/pci/drm/i915/gt/intel_engine_cs.c
+++ b/sys/dev/pci/drm/i915/gt/intel_engine_cs.c
@@ -916,6 +916,23 @@ static intel_engine_mask_t init_engine_mask(struct intel_gt *gt)
 		info->engine_mask &= ~BIT(GSC0);
 	}
 
+	/*
+	 * Do not create the command streamer for CCS slices beyond the first.
+	 * All the workload submitted to the first engine will be shared among
+	 * all the slices.
+	 *
+	 * Once the user will be allowed to customize the CCS mode, then this
+	 * check needs to be removed.
+	 */
+	if (IS_DG2(gt->i915)) {
+		u8 first_ccs = __ffs(CCS_MASK(gt));
+
+		/* Mask off all the CCS engine */
+		info->engine_mask &= ~GENMASK(CCS3, CCS0);
+		/* Put back in the first CCS engine */
+		info->engine_mask |= BIT(_CCS(first_ccs));
+	}
+
 	return info->engine_mask;
 }