From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75AD74431 for ; Wed, 15 Mar 2023 12:16:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CAE5DC433EF; Wed, 15 Mar 2023 12:16:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678882593; bh=oGfP/TGRqajg7DGuCoXIX3vu2u9JvvpSXZJMeoi7bm4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DmSExJFs89SII8DUBmRfnFP+ZGBSoWwkpDI5pNJ3b56K56PU786caVcZofk6ULY4V TYK+03LjvHMNr2XwutWNNHhu6COPQ3JQNXkTelkuvp4grDaQIaS0L0mrwjmaTZ57mX org3wxJ729N+kjQX3Umo2CJEWnxFMyM6otMU33oU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, John Harrison , Chris Wilson , Joonas Lahtinen , Jani Nikula , Rodrigo Vivi , Tvrtko Ursulin , intel-gfx@lists.freedesktop.org, =?UTF-8?q?Jouni=20H=C3=B6gander?= , Daniele Ceraolo Spurio , Jani Nikula Subject: [PATCH 4.19 36/39] drm/i915: Dont use BAR mappings for ring buffers with LLC Date: Wed, 15 Mar 2023 13:12:50 +0100 Message-Id: <20230315115722.581384565@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230315115721.234756306@linuxfoundation.org> References: <20230315115721.234756306@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: John Harrison commit 85636167e3206c3fbd52254fc432991cc4e90194 upstream. Direction from hardware is that ring buffers should never be mapped via the BAR on systems with LLC. There are too many caching pitfalls due to the way BAR accesses are routed. So it is safest to just not use it. Signed-off-by: John Harrison Fixes: 9d80841ea4c9 ("drm/i915: Allow ringbuffers to be bound anywhere") Cc: Chris Wilson Cc: Joonas Lahtinen Cc: Jani Nikula Cc: Rodrigo Vivi Cc: Tvrtko Ursulin Cc: intel-gfx@lists.freedesktop.org Cc: # v4.9+ Tested-by: Jouni Högander Reviewed-by: Daniele Ceraolo Spurio Link: https://patchwork.freedesktop.org/patch/msgid/20230216011101.1909009-3-John.C.Harrison@Intel.com (cherry picked from commit 65c08339db1ada87afd6cfe7db8e60bb4851d919) Signed-off-by: Jani Nikula Signed-off-by: John Harrison Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_ringbuffer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -1083,7 +1083,7 @@ int intel_ring_pin(struct intel_ring *ri if (unlikely(ret)) return ret; - if (i915_vma_is_map_and_fenceable(vma)) + if (i915_vma_is_map_and_fenceable(vma) && !HAS_LLC(vma->vm->i915)) addr = (void __force *)i915_vma_pin_iomap(vma); else addr = i915_gem_object_pin_map(vma->obj, map); @@ -1118,7 +1118,7 @@ void intel_ring_unpin(struct intel_ring /* Discard any unused bytes beyond that submitted to hw. */ intel_ring_reset(ring, ring->tail); - if (i915_vma_is_map_and_fenceable(ring->vma)) + if (i915_vma_is_map_and_fenceable(ring->vma) && !HAS_LLC(ring->vma->vm->i915)) i915_vma_unpin_iomap(ring->vma); else i915_gem_object_unpin_map(ring->vma->obj);