From c67e5e959ef20e9bf43fcdbdd928287f56bff998 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
Date: Thu, 14 Oct 2021 12:09:38 +0300
Subject: drm/i915: Replace the unconditional clflush with
 drm_clflush_virt_range()
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Git-commit: ef7ec41f17cbc0861891ccc0634d06a0c8dcbf09
Patch-mainline: v5.16-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

Not all machines have clflush, so don't go assuming they do.
Not really sure why the clflush is even here since hwsp
is supposed to get snooped I thought.

Although in my case we're talking about a i830 machine where
render/blitter snooping is definitely busted. But it might
work for the hswp perhaps. Haven't really reverse engineered
that one fully.

Cc: stable@vger.kernel.org
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Fixes: b436a5f8b6c8 ("drm/i915/gt: Track all timelines created using the HWSP")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014090941.12159-2-ville.syrjala@linux.intel.com
Reviewed-by: Dave Airlie <airlied@redhat.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/gt/intel_ring_submission.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -292,7 +292,7 @@
 	sanitize_hwsp(engine);
 
 	/* And scrub the dirty cachelines for the HWSP */
-	clflush_cache_range(engine->status_page.addr, PAGE_SIZE);
+	drm_clflush_virt_range(engine->status_page.addr, PAGE_SIZE);
 
 	intel_engine_reset_pinned_contexts(engine);
 }