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-rw-r--r--0013-drm-i915-gt-Detect-if-we-miss-WaIdleLiteRestore.patch130
1 files changed, 0 insertions, 130 deletions
diff --git a/0013-drm-i915-gt-Detect-if-we-miss-WaIdleLiteRestore.patch b/0013-drm-i915-gt-Detect-if-we-miss-WaIdleLiteRestore.patch
deleted file mode 100644
index 5ee3f39..0000000
--- a/0013-drm-i915-gt-Detect-if-we-miss-WaIdleLiteRestore.patch
+++ /dev/null
@@ -1,130 +0,0 @@
-From 8c19c0f7eacb125b9a097d080a385d527f8ff836 Mon Sep 17 00:00:00 2001
-From: Chris Wilson <chris@chris-wilson.co.uk>
-Date: Mon, 30 Dec 2019 11:15:30 +0000
-Subject: drm/i915/gt: Detect if we miss WaIdleLiteRestore
-
-In order to avoid confusing the HW, we must never submit an empty ring
-during lite-restore, that is we should always advance the RING_TAIL
-before submitting to stay ahead of the RING_HEAD.
-
-Normally this is prevented by keeping a couple of spare NOPs in the
-request->wa_tail so that on resubmission we can advance the tail. This
-relies on the request only being resubmitted once, which is the normal
-condition as it is seen once for ELSP[1] and then later in ELSP[0]. On
-preemption, the requests are unwound and the tail reset back to the
-normal end point (as we know the request is incomplete and therefore its
-RING_HEAD is even earlier).
-
-However, if this w/a should fail we would try and resubmit the request
-with the RING_TAIL already set to the location of this request's wa_tail
-potentially causing a GPU hang. We can spot when we do try and
-incorrectly resubmit without advancing the RING_TAIL and spare any
-embarrassment by forcing the context restore.
-
-In the case of preempt-to-busy, we leave the requests running on the HW
-while we unwind. As the ring is still live, we cannot rewind our
-rq->tail without forcing a reload so leave it set to rq->wa_tail and
-only force a reload if we resubmit after a lite-restore. (Normally, the
-forced reload will be a part of the preemption event.)
-
-Fixes: 22b7a426bbe1 ("drm/i915/execlists: Preempt-to-busy")
-Closes: https://gitlab.freedesktop.org/drm/intel/issues/673
-Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
-Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
-Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
-Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
-Cc: stable@vger.kernel.org
-Link: https://patchwork.freedesktop.org/patch/msgid/20191209023215.3519970-1-chris@chris-wilson.co.uk
-(cherry picked from commit 82c69bf58650e644c61aa2bf5100b63a1070fd2f)
----
- drivers/gpu/drm/i915/gt/intel_lrc.c | 42 ++++++++++++++++++-------------------
- 1 file changed, 20 insertions(+), 22 deletions(-)
-
-diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
-index 06a506c29463..6600b2e08fe3 100644
---- a/drivers/gpu/drm/i915/gt/intel_lrc.c
-+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
-@@ -471,12 +471,6 @@ lrc_descriptor(struct intel_context *ce, struct intel_engine_cs *engine)
- return desc;
- }
-
--static void unwind_wa_tail(struct i915_request *rq)
--{
-- rq->tail = intel_ring_wrap(rq->ring, rq->wa_tail - WA_TAIL_BYTES);
-- assert_ring_tail_valid(rq->ring, rq->tail);
--}
--
- static struct i915_request *
- __unwind_incomplete_requests(struct intel_engine_cs *engine)
- {
-@@ -495,7 +489,6 @@ __unwind_incomplete_requests(struct intel_engine_cs *engine)
- continue; /* XXX */
-
- __i915_request_unsubmit(rq);
-- unwind_wa_tail(rq);
-
- /*
- * Push the request back into the queue for later resubmission.
-@@ -649,13 +642,29 @@ execlists_schedule_out(struct i915_request *rq)
- i915_request_put(rq);
- }
-
--static u64 execlists_update_context(const struct i915_request *rq)
-+static u64 execlists_update_context(struct i915_request *rq)
- {
- struct intel_context *ce = rq->hw_context;
-- u64 desc;
-+ u64 desc = ce->lrc_desc;
-+ u32 tail;
-
-- ce->lrc_reg_state[CTX_RING_TAIL + 1] =
-- intel_ring_set_tail(rq->ring, rq->tail);
-+ /*
-+ * WaIdleLiteRestore:bdw,skl
-+ *
-+ * We should never submit the context with the same RING_TAIL twice
-+ * just in case we submit an empty ring, which confuses the HW.
-+ *
-+ * We append a couple of NOOPs (gen8_emit_wa_tail) after the end of
-+ * the normal request to be able to always advance the RING_TAIL on
-+ * subsequent resubmissions (for lite restore). Should that fail us,
-+ * and we try and submit the same tail again, force the context
-+ * reload.
-+ */
-+ tail = intel_ring_set_tail(rq->ring, rq->tail);
-+ if (unlikely(ce->lrc_reg_state[CTX_RING_TAIL + 1] == tail))
-+ desc |= CTX_DESC_FORCE_RESTORE;
-+ ce->lrc_reg_state[CTX_RING_TAIL + 1] = tail;
-+ rq->tail = rq->wa_tail;
-
- /*
- * Make sure the context image is complete before we submit it to HW.
-@@ -674,7 +683,6 @@ static u64 execlists_update_context(const struct i915_request *rq)
- */
- mb();
-
-- desc = ce->lrc_desc;
- ce->lrc_desc &= ~CTX_DESC_FORCE_RESTORE;
-
- return desc;
-@@ -1149,16 +1157,6 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
- if (!list_is_last(&last->sched.link,
- &engine->active.requests))
- return;
--
-- /*
-- * WaIdleLiteRestore:bdw,skl
-- * Apply the wa NOOPs to prevent
-- * ring:HEAD == rq:TAIL as we resubmit the
-- * request. See gen8_emit_fini_breadcrumb() for
-- * where we prepare the padding after the
-- * end of the request.
-- */
-- last->tail = last->wa_tail;
- }
- }
-
---
-cgit v1.2.1-1-g437b
-
-