From 3148310792b64c1b79e8ce399afccad369d4b17a Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu, 8 Aug 2019 08:41:52 +0100
Subject: [PATCH] drm/i915: Drop the fudge warning on ring restart for ctg/elk
Git-commit: 3148310792b64c1b79e8ce399afccad369d4b17a
Patch-mainline: v5.4-rc1
References: jsc#SLE-7953
Since we have already stopped the ring, cleared the ring, disabled the
ring (and verifying the ring is clear), a later debug message that the
ring is no longer clear serves no function. It appears it restarts
anyway, and we verify that the ring started correctly afterwards.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190808074207.18274-4-chris@chris-wilson.co.uk
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/gt/intel_ringbuffer.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_ringbuffer.c b/drivers/gpu/drm/i915/gt/intel_ringbuffer.c
index aa2f06b80961..78b4235f9c0f 100644
--- a/drivers/gpu/drm/i915/gt/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/gt/intel_ringbuffer.c
@@ -644,6 +644,7 @@ static int xcs_resume(struct intel_engine_cs *engine)
intel_uncore_forcewake_get(engine->uncore, FORCEWAKE_ALL);
+ /* WaClearRingBufHeadRegAtInit:ctg,elk */
if (!stop_ring(engine)) {
/* G45 ring initialization often fails to reset head to zero */
DRM_DEBUG_DRIVER("%s head not reset to zero "
@@ -675,19 +676,16 @@ static int xcs_resume(struct intel_engine_cs *engine)
intel_engine_reset_breadcrumbs(engine);
/* Enforce ordering by reading HEAD register back */
- ENGINE_READ(engine, RING_HEAD);
+ ENGINE_POSTING_READ(engine, RING_HEAD);
- /* Initialize the ring. This must happen _after_ we've cleared the ring
+ /*
+ * Initialize the ring. This must happen _after_ we've cleared the ring
* registers with the above sequence (the readback of the HEAD registers
* also enforces ordering), otherwise the hw might lose the new ring
- * register values. */
+ * register values.
+ */
ENGINE_WRITE(engine, RING_START, i915_ggtt_offset(ring->vma));
- /* WaClearRingBufHeadRegAtInit:ctg,elk */
- if (ENGINE_READ(engine, RING_HEAD))
- DRM_DEBUG_DRIVER("%s initialization failed [head=%08x], fudging\n",
- engine->name, ENGINE_READ(engine, RING_HEAD));
-
/* Check that the ring offsets point within the ring! */
GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->head));
GEM_BUG_ON(!intel_ring_offset_valid(ring, ring->tail));
--
2.16.4