[PATCH 5.15 033/230] drm/i915: Replace the unconditional clflush with drm_clflush_virt_range()

Greg Kroah-Hartman
2022-07-11T09:41:28Z

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

[ Upstream commit ef7ec41f17cbc0861891ccc0634d06a0c8dcbf09 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/i915/gt/intel_ring_submission.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
index 6f2f6ba87397..02e18e70c78e 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -292,7 +292,7 @@ static void xcs_sanitize(struct intel_engine_cs *engine)
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);
}
--
2.35.1