After much hair pulling, resort to preallocating the ppGTT entries on
init to circumvent the apparent lack of PD invalidate following the
write to PP_DCLV upon switching mm between contexts (and here the same
context after binding new objects). However, the details of that PP_DCLV
invalidate are still unknown, and it appears we need to reload the mm
twice to cover over a timing issue. Worrying.
Fixes: 3dc007fe9b2b ("drm/i915/gtt: Downgrade gen7 (ivb, byt, hsw) back to aliasing-ppgtt")
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
---
.../gpu/drm/i915/gt/intel_ring_submission.c | 21 ++++++++-----------
drivers/gpu/drm/i915/i915_gem_gtt.c | 21 ++++++++++++-------
drivers/gpu/drm/i915/i915_gem_gtt.h | 1 +
drivers/gpu/drm/i915/i915_pci.c | 2 +-
4 files changed, 25 insertions(+), 20 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_ring_submission.c b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
index f25ceccb335e..f977fc27b001 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring_submission.c
@@ -1366,7 +1366,7 @@ static int load_pd_dir(struct i915_request *rq, const struct i915_ppgtt *ppgtt)
const struct intel_engine_cs * const engine = rq->engine;
u32 *cs;
- cs = intel_ring_begin(rq, 6);
+ cs = intel_ring_begin(rq, 10);
if (IS_ERR(cs))
return PTR_ERR(cs);
@@ -1374,6 +1374,12 @@ static int load_pd_dir(struct i915_request *rq, const struct i915_ppgtt *ppgtt)
*cs++ = i915_mmio_reg_offset(RING_PP_DIR_DCLV(engine->mmio_base));
*cs++ = PP_DIR_DCLV_2G;
+ *cs++ = MI_STORE_REGISTER_MEM | MI_SRM_LRM_GLOBAL_GTT;
+ *cs++ = i915_mmio_reg_offset(RING_PP_DIR_DCLV(engine->mmio_base));
+ *cs++ = intel_gt_scratch_offset(rq->engine->gt,
+ INTEL_GT_SCRATCH_FIELD_DEFAULT);
+ *cs++ = MI_NOOP;
+
*cs++ = MI_LOAD_REGISTER_IMM(1);
*cs++ = i915_mmio_reg_offset(RING_PP_DIR_BASE(engine->mmio_base));
*cs++ = px_base(ppgtt->pd)->ggtt_offset << 10;
@@ -1579,6 +1585,7 @@ static int switch_context(struct i915_request *rq)
{
struct intel_context *ce = rq->hw_context;
struct i915_address_space *vm = vm_alias(ce);
+ u32 hw_flags = 0;
int ret;
GEM_BUG_ON(HAS_EXECLISTS(rq->i915));
@@ -1590,19 +1597,9 @@ static int switch_context(struct i915_request *rq)
}
if (ce->state) {
- u32 hw_flags;
-
GEM_BUG_ON(rq->engine->id != RCS0);
- /*
- * The kernel context(s) is treated as pure scratch and is not
- * expected to retain any state (as we sacrifice it during
- * suspend and on resume it may be corrupted). This is ok,
- * as nothing actually executes using the kernel context; it
- * is purely used for flushing user contexts.
- */
- hw_flags = 0;
- if (i915_gem_context_is_kernel(rq->gem_context))
+ if (!rq->engine->default_state)
hw_flags = MI_RESTORE_INHIBIT;
ret = mi_set_context(rq, hw_flags);
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 6239a9adbf14..98835fea38a9 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -1692,7 +1692,6 @@ static int gen6_alloc_va_range(struct i915_address_space *vm,
intel_wakeref_t wakeref;
u64 from = start;
unsigned int pde;
- bool flush = false;
int ret = 0;
wakeref = intel_runtime_pm_get(&vm->i915->runtime_pm);
@@ -1717,11 +1716,6 @@ static int gen6_alloc_va_range(struct i915_address_space *vm,
spin_lock(&pd->lock);
if (pd->entry[pde] == &vm->scratch[1]) {
pd->entry[pde] = pt;
- if (i915_vma_is_bound(ppgtt->vma,
- I915_VMA_GLOBAL_BIND)) {
- gen6_write_pde(ppgtt, pde, pt);
- flush = true;
- }
} else {
alloc = pt;
pt = pd->entry[pde];
@@ -1732,9 +1726,19 @@ static int gen6_alloc_va_range(struct i915_address_space *vm,
}
spin_unlock(&pd->lock);
- if (flush)
+ if (i915_vma_is_bound(ppgtt->vma, I915_VMA_GLOBAL_BIND)) {
+ mutex_lock(&ppgtt->flush);
+
+ /* Rewrite them all! Anything less misses an invalidate. */
+ gen6_for_all_pdes(pt, pd, pde)
+ gen6_write_pde(ppgtt, pde, pt);
+
+ ioread32(ppgtt->pd_addr + pde - 1);
gen6_ggtt_invalidate(vm->gt->ggtt);
+ mutex_unlock(&ppgtt->flush);
+ }
+
goto out;
unwind_out:
@@ -1793,6 +1797,7 @@ static void gen6_ppgtt_cleanup(struct i915_address_space *vm)
gen6_ppgtt_free_pd(ppgtt);
free_scratch(vm);
+ mutex_destroy(&ppgtt->flush);
mutex_destroy(&ppgtt->pin_mutex);
kfree(ppgtt->base.pd);
}
@@ -1958,6 +1963,7 @@ static struct i915_ppgtt *gen6_ppgtt_create(struct drm_i915_private *i915)
if (!ppgtt)
return ERR_PTR(-ENOMEM);
+ mutex_init(&ppgtt->flush);
mutex_init(&ppgtt->pin_mutex);
ppgtt_init(&ppgtt->base, &i915->gt);
@@ -1994,6 +2000,7 @@ static struct i915_ppgtt *gen6_ppgtt_create(struct drm_i915_private *i915)
err_pd:
kfree(ppgtt->base.pd);
err_free:
+ mutex_destroy(&ppgtt->pin_mutex);
kfree(ppgtt);
return ERR_PTR(err);
}
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 402283ce2864..31a4a96ddd0d 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -443,6 +443,7 @@ struct i915_ppgtt {
struct gen6_ppgtt {
struct i915_ppgtt base;
+ struct mutex flush;
struct i915_vma *vma;
gen6_pte_t __iomem *pd_addr;
diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c
index da3e9b5752ac..583e0cd94a6a 100644
--- a/drivers/gpu/drm/i915/i915_pci.c
+++ b/drivers/gpu/drm/i915/i915_pci.c
@@ -436,7 +436,7 @@ static const struct intel_device_info intel_sandybridge_m_gt2_info = {
.has_rc6 = 1, \
.has_rc6p = 1, \
.has_rps = true, \
- .ppgtt_type = INTEL_PPGTT_ALIASING, \
+ .ppgtt_type = INTEL_PPGTT_FULL, \
.ppgtt_size = 31, \
IVB_PIPE_OFFSETS, \
IVB_CURSOR_OFFSETS, \
--
2.24.0
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
