drm/i915/bdw: Initialization for Logical Ring Contexts
For the moment this is just a placeholder, but it shows one of the
main differences between the good ol' HW contexts and the shiny
new Logical Ring Contexts: LR contexts allocate and free their
own backing objects. Another difference is that the allocation is
deferred (as the create function name suggests), but that does not
happen in this patch yet, because for the moment we are only dealing
with the default context.
Early in the series we had our own gen8_gem_context_init/fini
functions, but the truth is they now look almost the same as the
legacy hw context init/fini functions. We can always split them
later if this ceases to be the case.
Also, we do not fall back to legacy ringbuffers when logical ring
context initialization fails (not very likely to happen and, even
if it does, hw contexts would probably fail as well).
v2: Daniel says "explain, do not showcase".
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
[danvet: s/BUG_ON/WARN_ON/.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 3b99390..3552a35 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -182,7 +182,10 @@
typeof(*ctx), ref);
struct i915_hw_ppgtt *ppgtt = NULL;
- if (ctx->legacy_hw_ctx.rcs_state) {
+ if (i915.enable_execlists) {
+ ppgtt = ctx_to_ppgtt(ctx);
+ intel_lr_context_free(ctx);
+ } else if (ctx->legacy_hw_ctx.rcs_state) {
/* We refcount even the aliasing PPGTT to keep the code symmetric */
if (USES_PPGTT(ctx->legacy_hw_ctx.rcs_state->base.dev))
ppgtt = ctx_to_ppgtt(ctx);
@@ -417,7 +420,11 @@
if (WARN_ON(dev_priv->ring[RCS].default_context))
return 0;
- if (HAS_HW_CONTEXTS(dev)) {
+ if (i915.enable_execlists) {
+ /* NB: intentionally left blank. We will allocate our own
+ * backing objects as we need them, thank you very much */
+ dev_priv->hw_context_size = 0;
+ } else if (HAS_HW_CONTEXTS(dev)) {
dev_priv->hw_context_size = round_up(get_context_size(dev), 4096);
if (dev_priv->hw_context_size > (1<<20)) {
DRM_DEBUG_DRIVER("Disabling HW Contexts; invalid size %d\n",
@@ -433,11 +440,20 @@
return PTR_ERR(ctx);
}
- /* NB: RCS will hold a ref for all rings */
- for (i = 0; i < I915_NUM_RINGS; i++)
- dev_priv->ring[i].default_context = ctx;
+ for (i = 0; i < I915_NUM_RINGS; i++) {
+ struct intel_engine_cs *ring = &dev_priv->ring[i];
- DRM_DEBUG_DRIVER("%s context support initialized\n", dev_priv->hw_context_size ? "HW" : "fake");
+ /* NB: RCS will hold a ref for all rings */
+ ring->default_context = ctx;
+
+ /* FIXME: we really only want to do this for initialized rings */
+ if (i915.enable_execlists)
+ intel_lr_context_deferred_create(ctx, ring);
+ }
+
+ DRM_DEBUG_DRIVER("%s context support initialized\n",
+ i915.enable_execlists ? "LR" :
+ dev_priv->hw_context_size ? "HW" : "fake");
return 0;
}
@@ -779,6 +795,7 @@
struct intel_context *ctx;
int ret;
+ /* FIXME: allow user-created LR contexts as well */
if (!hw_context_enabled(dev))
return -ENODEV;