On 8/20/2021 15:44, Matthew Brost wrote:
Add multi-lrc context registration H2G. In addition a workqueue and
process descriptor are setup during multi-lrc context registration as
these data structures are needed for multi-lrc submission.
Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
---
drivers/gpu/drm/i915/gt/intel_context_types.h | 12 ++
drivers/gpu/drm/i915/gt/intel_lrc.c | 5 +
drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h | 2 +-
.../gpu/drm/i915/gt/uc/intel_guc_submission.c | 109 +++++++++++++++++-
4 files changed, 126 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h
index 0fafc178cf2c..6f567ebeb039 100644
--- a/drivers/gpu/drm/i915/gt/intel_context_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_context_types.h
@@ -232,8 +232,20 @@ struct intel_context {
/** @parent: pointer to parent if child */
struct intel_context *parent;
+
+ /** @guc_wqi_head: head pointer in work queue */
+ u16 guc_wqi_head;
+ /** @guc_wqi_tail: tail pointer in work queue */
+ u16 guc_wqi_tail;
+
These should be in the 'guc_state' sub-struct? Would be good to keep all
GuC specific content in one self-contained struct. Especially given the
other child/parent fields are no going to be guc_ prefixed any more.
/** @guc_number_children: number of children if parent */
u8 guc_number_children;
+
+ /**
+ * @parent_page: page in context used by parent for work queue,
Maybe 'page in context record'? Otherwise, exactly what 'context' is
meant here? It isn't the 'struct intel_context'. The contetx record is
saved as 'ce->state' / 'ce->lrc_reg_state', yes? Is it possible to link
to either of those field? Probably not given that they don't appear to
have any kerneldoc description :(. Maybe add that in too :).
+ * work queue descriptor
Later on, it is described as 'process descriptor and work queue'. It
would be good to be consistent.
+ */
+ u8 parent_page;
};
#ifdef CONFIG_DRM_I915_SELFTEST
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index bb4af4977920..0ddbad4e062a 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -861,6 +861,11 @@ __lrc_alloc_state(struct intel_context *ce, struct intel_engine_cs *engine)
context_size += PAGE_SIZE;
}
+ if (intel_context_is_parent(ce)) {
+ ce->parent_page = context_size / PAGE_SIZE;
+ context_size += PAGE_SIZE;
+ }
+
obj = i915_gem_object_create_lmem(engine->i915, context_size, 0);
if (IS_ERR(obj))
obj = i915_gem_object_create_shmem(engine->i915, context_size);
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h
index fa4be13c8854..0e600a3b8f1e 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_fwif.h
@@ -52,7 +52,7 @@
#define GUC_DOORBELL_INVALID 256
-#define GUC_WQ_SIZE (PAGE_SIZE * 2)
+#define GUC_WQ_SIZE (PAGE_SIZE / 2)
Is this size actually dictated by the GuC API? Or is it just a driver
level decision? If the latter, shouldn't this be below instead?
/* Work queue item header definitions */
#define WQ_STATUS_ACTIVE 1
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index 14b24298cdd7..dbcb9ab28a9a 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -340,6 +340,39 @@ static struct i915_priolist *to_priolist(struct rb_node *rb)
return rb_entry(rb, struct i915_priolist, node);
}
+/*
+ * When using multi-lrc submission an extra page in the context state is
+ * reserved for the process descriptor and work queue.
+ *
+ * The layout of this page is below:
+ * 0 guc_process_desc
+ * ... unused
+ * PAGE_SIZE / 2 work queue start
+ * ... work queue
+ * PAGE_SIZE - 1 work queue end
+ */
+#define WQ_OFFSET (PAGE_SIZE / 2)
Can this not be derived from GUC_WQ_SIZE given that the two are
fundamentally linked? E.g. '#define WQ_OFFSET (PAGE_SIZE -
GUC_WQ_SIZE)'? And maybe have a '#define WQ_TOTAL_SIZE PAGE_SIZE' and
use that in all of WQ_OFFSET, GUC_WQ_SIZE and the allocation itself in
intel_lrc.c?
Also, the process descriptor is actually an array of descriptors sized
by the number of children? Or am I misunderstanding the code below? In
so, shouldn't there be a 'COMPILE_BUG_ON((MAX_ENGINE_INSTANCE *
sizeof(descriptor)) < (WQ_DESC_SIZE)' where WQ_DESC_SIZE is
WQ_TOTAL_SIZE - WQ_SIZE?
+static u32 __get_process_desc_offset(struct intel_context *ce)
+{
+ GEM_BUG_ON(!ce->parent_page);
+
+ return ce->parent_page * PAGE_SIZE;
+}
+
+static u32 __get_wq_offset(struct intel_context *ce)
+{
+ return __get_process_desc_offset(ce) + WQ_OFFSET;
+}
+
+static struct guc_process_desc *
+__get_process_desc(struct intel_context *ce)
+{
+ return (struct guc_process_desc *)
+ (ce->lrc_reg_state +
+ ((__get_process_desc_offset(ce) -
+ LRC_STATE_OFFSET) / sizeof(u32)));
Where did the LRC_STATE_OFFSET come from? Is that built in to the
lrg_reg_state pointer itself? That needs to be documented somewhere.
+}
+
static struct guc_lrc_desc *__get_lrc_desc(struct intel_guc *guc, u32 index)
{
struct guc_lrc_desc *base = guc->lrc_desc_pool_vaddr;
@@ -1342,6 +1375,30 @@ static void unpin_guc_id(struct intel_guc *guc, struct intel_context *ce)
spin_unlock_irqrestore(&guc->submission_state.lock, flags);
}
+static int __guc_action_register_multi_lrc(struct intel_guc *guc,
+ struct intel_context *ce,
+ u32 guc_id,
+ u32 offset,
+ bool loop)
+{
+ struct intel_context *child;
+ u32 action[4 + MAX_ENGINE_INSTANCE];
+ int len = 0;
+
+ GEM_BUG_ON(ce->guc_number_children > MAX_ENGINE_INSTANCE);
+
+ action[len++] = INTEL_GUC_ACTION_REGISTER_CONTEXT_MULTI_LRC;
+ action[len++] = guc_id;
+ action[len++] = ce->guc_number_children + 1;
+ action[len++] = offset;
+ for_each_child(ce, child) {
+ offset += sizeof(struct guc_lrc_desc);
+ action[len++] = offset;
+ }
+
+ return guc_submission_send_busy_loop(guc, action, len, 0, loop);
+}
+
static int __guc_action_register_context(struct intel_guc *guc,
u32 guc_id,
u32 offset,
@@ -1364,9 +1421,15 @@ static int register_context(struct intel_context *ce, bool loop)
ce->guc_id.id * sizeof(struct guc_lrc_desc);
int ret;
+ GEM_BUG_ON(intel_context_is_child(ce));
trace_intel_context_register(ce);
- ret = __guc_action_register_context(guc, ce->guc_id.id, offset, loop);
+ if (intel_context_is_parent(ce))
+ ret = __guc_action_register_multi_lrc(guc, ce, ce->guc_id.id,
+ offset, loop);
+ else
+ ret = __guc_action_register_context(guc, ce->guc_id.id, offset,
+ loop);
if (likely(!ret)) {
unsigned long flags;
@@ -1396,6 +1459,7 @@ static int deregister_context(struct intel_context *ce, u32 guc_id, bool loop)
{
struct intel_guc *guc = ce_to_guc(ce);
+ GEM_BUG_ON(intel_context_is_child(ce));
trace_intel_context_deregister(ce);
return __guc_action_deregister_context(guc, guc_id, loop);
@@ -1423,6 +1487,7 @@ static int guc_lrc_desc_pin(struct intel_context *ce, bool loop)
struct guc_lrc_desc *desc;
bool context_registered;
intel_wakeref_t wakeref;
+ struct intel_context *child;
int ret = 0;
GEM_BUG_ON(!engine->mask);
@@ -1448,6 +1513,42 @@ static int guc_lrc_desc_pin(struct intel_context *ce, bool loop)
desc->context_flags = CONTEXT_REGISTRATION_FLAG_KMD;
guc_context_policy_init(engine, desc);
+ /*
+ * Context is a parent, we need to register a process descriptor
+ * describing a work queue and register all child contexts.
Technically, this should say 'If the context is a parent'. Or just move
it to be inside the if block.
+ */
+ if (intel_context_is_parent(ce)) {
+ struct guc_process_desc *pdesc;
+
+ ce->guc_wqi_tail = 0;
+ ce->guc_wqi_head = 0;
+
+ desc->process_desc = i915_ggtt_offset(ce->state) +
+ __get_process_desc_offset(ce);
+ desc->wq_addr = i915_ggtt_offset(ce->state) +
+ __get_wq_offset(ce);
+ desc->wq_size = GUC_WQ_SIZE;
+
+ pdesc = __get_process_desc(ce);
+ memset(pdesc, 0, sizeof(*(pdesc)));
+ pdesc->stage_id = ce->guc_id.id;
+ pdesc->wq_base_addr = desc->wq_addr;
+ pdesc->wq_size_bytes = desc->wq_size;
+ pdesc->priority = GUC_CLIENT_PRIORITY_KMD_NORMAL;
Should this not be inherited from the ce? And same below. Or are we not
using this priority in that way?
John.
+ pdesc->wq_status = WQ_STATUS_ACTIVE;
+
+ for_each_child(ce, child) {
+ desc = __get_lrc_desc(guc, child->guc_id.id);
+
+ desc->engine_class =
+ engine_class_to_guc_class(engine->class);
+ desc->hw_context_desc = child->lrc.lrca;
+ desc->priority = GUC_CLIENT_PRIORITY_KMD_NORMAL;
+ desc->context_flags = CONTEXT_REGISTRATION_FLAG_KMD;
+ guc_context_policy_init(engine, desc);
+ }
+ }
+
/*
* The context_lookup xarray is used to determine if the hardware
* context is currently registered. There are two cases in which it
@@ -2858,6 +2959,12 @@ g2h_context_lookup(struct intel_guc *guc, u32 desc_idx)
return NULL;
}
+ if (unlikely(intel_context_is_child(ce))) {
+ drm_err(&guc_to_gt(guc)->i915->drm,
+ "Context is child, desc_idx %u", desc_idx);
+ return NULL;
+ }
+
return ce;
}
