From dee60ca1f35234d890977c095410ed6ac1dcfc33 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 14 Sep 2018 13:35:02 +0100 Subject: [PATCH] drm/i915/execlists: Delay updating ring register state after resume Now that we reload both RING_HEAD and RING_TAIL when rebinding the context, we do not need to scrub those registers immediately on resume. v2: Handle the perma-pinned contexts. v3: Set RING_TAIL on context-pin so that we always have known state in the context image for the ring registers and all parties have similar code (ripe for refactoring). Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Cc: Mika Kuoppala Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20180914123504.2062-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/intel_lrc.c | 33 +++++++++++++++----------------- 1 file changed, 15 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 9b1f0e5211a0..d7fcbba8e982 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -1338,11 +1338,13 @@ __execlists_context_pin(struct intel_engine_cs *engine, intel_lr_context_descriptor_update(ctx, engine, ce); + GEM_BUG_ON(!intel_ring_offset_valid(ce->ring, ce->ring->head)); + ce->lrc_reg_state = vaddr + LRC_STATE_PN * PAGE_SIZE; ce->lrc_reg_state[CTX_RING_BUFFER_START+1] = i915_ggtt_offset(ce->ring->vma); - GEM_BUG_ON(!intel_ring_offset_valid(ce->ring, ce->ring->head)); - ce->lrc_reg_state[CTX_RING_HEAD+1] = ce->ring->head; + ce->lrc_reg_state[CTX_RING_HEAD + 1] = ce->ring->head; + ce->lrc_reg_state[CTX_RING_TAIL + 1] = ce->ring->tail; ce->state->obj->pin_global++; i915_gem_context_get(ctx); @@ -2841,13 +2843,14 @@ error_deref_obj: return ret; } -void intel_lr_context_resume(struct drm_i915_private *dev_priv) +void intel_lr_context_resume(struct drm_i915_private *i915) { struct intel_engine_cs *engine; struct i915_gem_context *ctx; enum intel_engine_id id; - /* Because we emit WA_TAIL_DWORDS there may be a disparity + /* + * Because we emit WA_TAIL_DWORDS there may be a disparity * between our bookkeeping in ce->ring->head and ce->ring->tail and * that stored in context. As we only write new commands from * ce->ring->tail onwards, everything before that is junk. If the GPU @@ -2857,28 +2860,22 @@ void intel_lr_context_resume(struct drm_i915_private *dev_priv) * So to avoid that we reset the context images upon resume. For * simplicity, we just zero everything out. */ - list_for_each_entry(ctx, &dev_priv->contexts.list, link) { - for_each_engine(engine, dev_priv, id) { + list_for_each_entry(ctx, &i915->contexts.list, link) { + for_each_engine(engine, i915, id) { struct intel_context *ce = to_intel_context(ctx, engine); - u32 *reg; if (!ce->state) continue; - reg = i915_gem_object_pin_map(ce->state->obj, - I915_MAP_WB); - if (WARN_ON(IS_ERR(reg))) - continue; - - reg += LRC_STATE_PN * PAGE_SIZE / sizeof(*reg); - reg[CTX_RING_HEAD+1] = 0; - reg[CTX_RING_TAIL+1] = 0; + intel_ring_reset(ce->ring, 0); - ce->state->obj->mm.dirty = true; - i915_gem_object_unpin_map(ce->state->obj); + if (ce->pin_count) { /* otherwise done in context_pin */ + u32 *regs = ce->lrc_reg_state; - intel_ring_reset(ce->ring, 0); + regs[CTX_RING_HEAD + 1] = ce->ring->head; + regs[CTX_RING_TAIL + 1] = ce->ring->tail; + } } } } -- 2.30.2