static int render_state_init(struct render_state *so, struct drm_device *dev)
{
int ret;
so->gen = INTEL_INFO(dev)->gen;
so->rodata = render_state_get_rodata(dev, so->gen);
if (so->rodata == NULL)
return 0;
if (so->rodata->batch_items * 4 > 4096)
return -EINVAL;
so->obj = i915_gem_alloc_object(dev, 4096);
if (so->obj == NULL)
return -ENOMEM;
ret = i915_gem_obj_ggtt_pin(so->obj, 4096, 0);
if (ret)
goto free_gem;
so->ggtt_offset = i915_gem_obj_ggtt_offset(so->obj);
return 0;
free_gem:
drm_gem_object_unreference(&so->obj->base);
return ret;
}
/**
* The default context needs to exist per ring that uses contexts. It stores the
* context state of the GPU for applications that don't utilize HW contexts, as
* well as an idle case.
*/
static struct intel_context *
i915_gem_create_context(struct drm_device *dev,
struct drm_i915_file_private *file_priv)
{
const bool is_global_default_ctx = file_priv == NULL;
struct intel_context *ctx;
int ret = 0;
BUG_ON(!mutex_is_locked(&dev->struct_mutex));
ctx = __create_hw_context(dev, file_priv);
if (IS_ERR(ctx))
return ctx;
if (is_global_default_ctx && ctx->legacy_hw_ctx.rcs_state) {
/* We may need to do things with the shrinker which
* require us to immediately switch back to the default
* context. This can cause a problem as pinning the
* default context also requires GTT space which may not
* be available. To avoid this we always pin the default
* context.
*/
ret = i915_gem_obj_ggtt_pin(ctx->legacy_hw_ctx.rcs_state,
get_context_alignment(dev), 0);
if (ret) {
DRM_DEBUG_DRIVER("Couldn't pin %d\n", ret);
goto err_destroy;
}
}
if (USES_FULL_PPGTT(dev)) {
struct i915_hw_ppgtt *ppgtt = i915_ppgtt_create(dev, file_priv);
if (IS_ERR_OR_NULL(ppgtt)) {
DRM_DEBUG_DRIVER("PPGTT setup failed (%ld)\n",
PTR_ERR(ppgtt));
ret = PTR_ERR(ppgtt);
goto err_unpin;
}
ctx->ppgtt = ppgtt;
}
trace_i915_context_create(ctx);
return ctx;
err_unpin:
if (is_global_default_ctx && ctx->legacy_hw_ctx.rcs_state)
i915_gem_object_ggtt_unpin(ctx->legacy_hw_ctx.rcs_state);
err_destroy:
i915_gem_context_unreference(ctx);
return ERR_PTR(ret);
}
static struct i915_render_state *render_state_alloc(struct drm_device *dev)
{
struct i915_render_state *so;
struct page *page;
int ret;
so = kzalloc(sizeof(*so), GFP_KERNEL);
if (!so)
return ERR_PTR(-ENOMEM);
so->obj = i915_gem_alloc_object(dev, 4096);
if (so->obj == NULL) {
ret = -ENOMEM;
goto free;
}
so->size = 4096;
ret = i915_gem_obj_ggtt_pin(so->obj, 4096, 0);
if (ret)
goto free_gem;
BUG_ON(so->obj->pages->nents != 1);
page = sg_page(so->obj->pages->sgl);
so->batch = kmap(page);
if (!so->batch) {
ret = -ENOMEM;
goto unpin;
}
so->ggtt_offset = i915_gem_obj_ggtt_offset(so->obj);
return so;
unpin:
i915_gem_object_ggtt_unpin(so->obj);
free_gem:
drm_gem_object_unreference(&so->obj->base);
free:
kfree(so);
return ERR_PTR(ret);
}
/**
* The default context needs to exist per ring that uses contexts. It stores the
* context state of the GPU for applications that don't utilize HW contexts, as
* well as an idle case.
*/
static int create_default_context(struct drm_i915_private *dev_priv)
{
struct i915_hw_context *ctx;
int ret;
BUG_ON(!mutex_is_locked(&dev_priv->dev->struct_mutex));
ctx = create_hw_context(dev_priv->dev, NULL);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
/* We may need to do things with the shrinker which require us to
* immediately switch back to the default context. This can cause a
* problem as pinning the default context also requires GTT space which
* may not be available. To avoid this we always pin the
* default context.
*/
ret = i915_gem_obj_ggtt_pin(ctx->obj, CONTEXT_ALIGN, false, false);
if (ret) {
DRM_DEBUG_DRIVER("Couldn't pin %d\n", ret);
goto err_destroy;
}
ret = do_switch(ctx);
if (ret) {
DRM_DEBUG_DRIVER("Switch failed %d\n", ret);
goto err_unpin;
}
dev_priv->ring[RCS].default_context = ctx;
DRM_DEBUG_DRIVER("Default HW context loaded\n");
return 0;
err_unpin:
i915_gem_object_unpin(ctx->obj);
err_destroy:
i915_gem_context_unreference(ctx);
return ret;
}
static int do_switch(struct i915_hw_context *to)
{
struct intel_ring_buffer *ring = to->ring;
struct i915_hw_context *from = ring->last_context;
u32 hw_flags = 0;
int ret, i;
BUG_ON(from != NULL && from->obj != NULL && from->obj->pin_count == 0);
if (from == to && !to->remap_slice)
return 0;
ret = i915_gem_obj_ggtt_pin(to->obj, CONTEXT_ALIGN, false, false);
if (ret)
return ret;
/*
* Pin can switch back to the default context if we end up calling into
* evict_everything - as a last ditch gtt defrag effort that also
* switches to the default context. Hence we need to reload from here.
*/
from = ring->last_context;
/*
* Clear this page out of any CPU caches for coherent swap-in/out. Note
* that thanks to write = false in this call and us not setting any gpu
* write domains when putting a context object onto the active list
* (when switching away from it), this won't block.
*
* XXX: We need a real interface to do this instead of trickery.
*/
ret = i915_gem_object_set_to_gtt_domain(to->obj, false);
if (ret) {
i915_gem_object_unpin(to->obj);
return ret;
}
if (!to->obj->has_global_gtt_mapping)
i915_gem_gtt_bind_object(to->obj, to->obj->cache_level);
if (!to->is_initialized || is_default_context(to))
hw_flags |= MI_RESTORE_INHIBIT;
ret = mi_set_context(ring, to, hw_flags);
if (ret) {
i915_gem_object_unpin(to->obj);
return ret;
}
for (i = 0; i < MAX_L3_SLICES; i++) {
if (!(to->remap_slice & (1<<i)))
continue;
ret = i915_gem_l3_remap(ring, i);
/* If it failed, try again next round */
if (ret)
DRM_DEBUG_DRIVER("L3 remapping failed\n");
else
to->remap_slice &= ~(1<<i);
}
/* The backing object for the context is done after switching to the
* *next* context. Therefore we cannot retire the previous context until
* the next context has already started running. In fact, the below code
* is a bit suboptimal because the retiring can occur simply after the
* MI_SET_CONTEXT instead of when the next seqno has completed.
*/
if (from != NULL) {
from->obj->base.read_domains = I915_GEM_DOMAIN_INSTRUCTION;
i915_vma_move_to_active(i915_gem_obj_to_ggtt(from->obj), ring);
/* As long as MI_SET_CONTEXT is serializing, ie. it flushes the
* whole damn pipeline, we don't need to explicitly mark the
* object dirty. The only exception is that the context must be
* correct in case the object gets swapped out. Ideally we'd be
* able to defer doing this until we know the object would be
* swapped, but there is no way to do that yet.
*/
from->obj->dirty = 1;
BUG_ON(from->obj->ring != ring);
/* obj is kept alive until the next request by its active ref */
i915_gem_object_unpin(from->obj);
i915_gem_context_unreference(from);
}
i915_gem_context_reference(to);
ring->last_context = to;
to->is_initialized = true;
return 0;
}
