drm/i915: Create a kernel context for GGTT updates

Create a separate kernel context if a platform requires
GGTT updates using MI_UPDATE_GTT blitter command.

Subsequent patch will introduce methods to update
GGTT using this bind context and MI_UPDATE_GTT blitter
command.

v2: fix context leak on err(Oak)
v3: improve err handling and improve function names(Andi)
    add docs for few functions.

Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Oak Zeng <oak.zeng@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230926083742.14740-3-nirmoy.das@intel.com

diff --git a/drivers/gpu/drm/i915/gt/intel_engine.h b/drivers/gpu/drm/i915/gt/intel_engine.h
index b58c30ac8ef0264cdf9f8f469e73f93f192d1b5d..40269e4c1e3128310c02a39f2ab47132af184146 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_engine.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine.h
@@ -170,6 +170,8 @@ intel_write_status_page(struct intel_engine_cs *engine, int reg, u32 value)
 #define I915_GEM_HWS_SEQNO             0x40
 #define I915_GEM_HWS_SEQNO_ADDR                (I915_GEM_HWS_SEQNO * sizeof(u32))
 #define I915_GEM_HWS_MIGRATE           (0x42 * sizeof(u32))
+#define I915_GEM_HWS_GGTT_BIND         0x46
+#define I915_GEM_HWS_GGTT_BIND_ADDR    (I915_GEM_HWS_GGTT_BIND * sizeof(u32))
 #define I915_GEM_HWS_PXP               0x60
 #define I915_GEM_HWS_PXP_ADDR          (I915_GEM_HWS_PXP * sizeof(u32))
 #define I915_GEM_HWS_GSC               0x62

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 84a75c95f3f7de7bee12493dff1490856111a703..64f51defc2cb33654906eec0f4361aae15e0d8e8 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -1418,6 +1418,20 @@ void intel_engine_destroy_pinned_context(struct intel_context *ce)
        intel_context_put(ce);
 }
 
+static struct intel_context *
+create_ggtt_bind_context(struct intel_engine_cs *engine)
+{
+       static struct lock_class_key kernel;
+
+       /*
+        * MI_UPDATE_GTT can insert up to 511 PTE entries and there could be multiple
+        * bind requets at a time so get a bigger ring.
+        */
+       return intel_engine_create_pinned_context(engine, engine->gt->vm, SZ_512K,
+                                                 I915_GEM_HWS_GGTT_BIND_ADDR,
+                                                 &kernel, "ggtt_bind_context");
+}
+
 static struct intel_context *
 create_kernel_context(struct intel_engine_cs *engine)
 {
@@ -1441,7 +1455,7 @@ create_kernel_context(struct intel_engine_cs *engine)
  */
 static int engine_init_common(struct intel_engine_cs *engine)
 {
-       struct intel_context *ce;
+       struct intel_context *ce, *bce = NULL;
        int ret;
 
        engine->set_default_submission(engine);
@@ -1457,17 +1471,33 @@ static int engine_init_common(struct intel_engine_cs *engine)
        ce = create_kernel_context(engine);
        if (IS_ERR(ce))
                return PTR_ERR(ce);
+       /*
+        * Create a separate pinned context for GGTT update with blitter engine
+        * if a platform require such service. MI_UPDATE_GTT works on other
+        * engines as well but BCS should be less busy engine so pick that for
+        * GGTT updates.
+        */
+       if (engine->id == BCS0) {
+               bce = create_ggtt_bind_context(engine);
+               if (IS_ERR(bce)) {
+                       ret = PTR_ERR(bce);
+                       goto err_ce_context;
+               }
+       }
 
        ret = measure_breadcrumb_dw(ce);
        if (ret < 0)
-               goto err_context;
+               goto err_bce_context;
 
        engine->emit_fini_breadcrumb_dw = ret;
        engine->kernel_context = ce;
+       engine->bind_context = bce;
 
        return 0;
 
-err_context:
+err_bce_context:
+       intel_engine_destroy_pinned_context(bce);
+err_ce_context:
        intel_engine_destroy_pinned_context(ce);
        return ret;
 }
@@ -1537,6 +1567,10 @@ void intel_engine_cleanup_common(struct intel_engine_cs *engine)
        if (engine->kernel_context)
                intel_engine_destroy_pinned_context(engine->kernel_context);
 
+       if (engine->bind_context)
+               intel_engine_destroy_pinned_context(engine->bind_context);
+
+
        GEM_BUG_ON(!llist_empty(&engine->barrier_tasks));
        cleanup_status_page(engine);
 

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_types.h b/drivers/gpu/drm/i915/gt/intel_engine_types.h
index a7e6775980043c9ce25fee01368d67378663bf44..a8f527fab0f0d753215a5f06c3623c721b4e1e7a 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_engine_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h
@@ -416,6 +416,9 @@ struct intel_engine_cs {
        struct llist_head barrier_tasks;
 
        struct intel_context *kernel_context; /* pinned */
+       struct intel_context *bind_context; /* pinned, only for BCS0 */
+       /* mark the bind context's availability status */
+       bool bind_context_ready;
 
        /**
         * pinned_contexts_list: List of pinned contexts. This list is only

diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index 9db97aa4d40c574f6c9e9753a52eee93507754fc..22730381554cc60aa94aa6021daed0a036a837ac 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -1035,3 +1035,52 @@ bool intel_gt_needs_wa_22016122933(struct intel_gt *gt)
 {
        return MEDIA_VER_FULL(gt->i915) == IP_VER(13, 0) && gt->type == GT_MEDIA;
 }
+
+static void __intel_gt_bind_context_set_ready(struct intel_gt *gt, bool ready)
+{
+       struct intel_engine_cs *engine = gt->engine[BCS0];
+
+       if (engine && engine->bind_context)
+               engine->bind_context_ready = ready;
+}
+
+/**
+ * intel_gt_bind_context_set_ready - Set the context binding as ready
+ *
+ * @gt: GT structure
+ *
+ * This function marks the binder context as ready.
+ */
+void intel_gt_bind_context_set_ready(struct intel_gt *gt)
+{
+       __intel_gt_bind_context_set_ready(gt, true);
+}
+
+/**
+ * intel_gt_bind_context_set_unready - Set the context binding as ready
+ * @gt: GT structure
+ *
+ * This function marks the binder context as not ready.
+ */
+
+void intel_gt_bind_context_set_unready(struct intel_gt *gt)
+{
+       __intel_gt_bind_context_set_ready(gt, false);
+}
+
+/**
+ * intel_gt_is_bind_context_ready - Check if context binding is ready
+ *
+ * @gt: GT structure
+ *
+ * This function returns binder context's ready status.
+ */
+bool intel_gt_is_bind_context_ready(struct intel_gt *gt)
+{
+       struct intel_engine_cs *engine = gt->engine[BCS0];
+
+       if (engine)
+               return engine->bind_context_ready;
+
+       return false;
+}

diff --git a/drivers/gpu/drm/i915/gt/intel_gt.h b/drivers/gpu/drm/i915/gt/intel_gt.h
index 2cac499d5aa3e57e15ffe7d90727e8a31253916e..970bedf6b78a7b82b69509b8f8c37c868ee81ccd 100644 (file)
--- a/drivers/gpu/drm/i915/gt/intel_gt.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt.h
@@ -176,4 +176,7 @@ enum i915_map_type intel_gt_coherent_map_type(struct intel_gt *gt,
                                              struct drm_i915_gem_object *obj,
                                              bool always_coherent);
 
+void intel_gt_bind_context_set_ready(struct intel_gt *gt);
+void intel_gt_bind_context_set_unready(struct intel_gt *gt);
+bool intel_gt_is_bind_context_ready(struct intel_gt *gt);
 #endif /* __INTEL_GT_H__ */