1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_global_state.c b/drivers/gpu/drm/i915/display/intel_global_state.c
new file mode 100644
index 000000000000..a0cc894c3868
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_global_state.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2020 Intel Corporation
+ */
+
+#include <linux/string.h>
+
+#include "i915_drv.h"
+#include "intel_atomic.h"
+#include "intel_display_types.h"
+#include "intel_global_state.h"
+
+void intel_atomic_global_obj_init(struct drm_i915_private *dev_priv,
+				  struct intel_global_obj *obj,
+				  struct intel_global_state *state,
+				  const struct intel_global_state_funcs *funcs)
+{
+	memset(obj, 0, sizeof(*obj));
+
+	obj->state = state;
+	obj->funcs = funcs;
+	list_add_tail(&obj->head, &dev_priv->global_obj_list);
+}
+
+void intel_atomic_global_obj_cleanup(struct drm_i915_private *dev_priv)
+{
+	struct intel_global_obj *obj, *next;
+
+	list_for_each_entry_safe(obj, next, &dev_priv->global_obj_list, head) {
+		list_del(&obj->head);
+		obj->funcs->atomic_destroy_state(obj, obj->state);
+	}
+}
+
+static void assert_global_state_write_locked(struct drm_i915_private *dev_priv)
+{
+	struct intel_crtc *crtc;
+
+	for_each_intel_crtc(&dev_priv->drm, crtc)
+		drm_modeset_lock_assert_held(&crtc->base.mutex);
+}
+
+static bool modeset_lock_is_held(struct drm_modeset_acquire_ctx *ctx,
+				 struct drm_modeset_lock *lock)
+{
+	struct drm_modeset_lock *l;
+
+	list_for_each_entry(l, &ctx->locked, head) {
+		if (lock == l)
+			return true;
+	}
+
+	return false;
+}
+
+static void assert_global_state_read_locked(struct intel_atomic_state *state)
+{
+	struct drm_modeset_acquire_ctx *ctx = state->base.acquire_ctx;
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	struct intel_crtc *crtc;
+
+	for_each_intel_crtc(&dev_priv->drm, crtc) {
+		if (modeset_lock_is_held(ctx, &crtc->base.mutex))
+			return;
+	}
+
+	WARN(1, "Global state not read locked\n");
+}
+
+struct intel_global_state *
+intel_atomic_get_global_obj_state(struct intel_atomic_state *state,
+				  struct intel_global_obj *obj)
+{
+	int index, num_objs, i;
+	size_t size;
+	struct __intel_global_objs_state *arr;
+	struct intel_global_state *obj_state;
+
+	for (i = 0; i < state->num_global_objs; i++)
+		if (obj == state->global_objs[i].ptr)
+			return state->global_objs[i].state;
+
+	assert_global_state_read_locked(state);
+
+	num_objs = state->num_global_objs + 1;
+	size = sizeof(*state->global_objs) * num_objs;
+	arr = krealloc(state->global_objs, size, GFP_KERNEL);
+	if (!arr)
+		return ERR_PTR(-ENOMEM);
+
+	state->global_objs = arr;
+	index = state->num_global_objs;
+	memset(&state->global_objs[index], 0, sizeof(*state->global_objs));
+
+	obj_state = obj->funcs->atomic_duplicate_state(obj);
+	if (!obj_state)
+		return ERR_PTR(-ENOMEM);
+
+	obj_state->changed = false;
+
+	state->global_objs[index].state = obj_state;
+	state->global_objs[index].old_state = obj->state;
+	state->global_objs[index].new_state = obj_state;
+	state->global_objs[index].ptr = obj;
+	obj_state->state = state;
+
+	state->num_global_objs = num_objs;
+
+	DRM_DEBUG_ATOMIC("Added new global object %p state %p to %p\n",
+			 obj, obj_state, state);
+
+	return obj_state;
+}
+
+struct intel_global_state *
+intel_atomic_get_old_global_obj_state(struct intel_atomic_state *state,
+				      struct intel_global_obj *obj)
+{
+	int i;
+
+	for (i = 0; i < state->num_global_objs; i++)
+		if (obj == state->global_objs[i].ptr)
+			return state->global_objs[i].old_state;
+
+	return NULL;
+}
+
+struct intel_global_state *
+intel_atomic_get_new_global_obj_state(struct intel_atomic_state *state,
+				      struct intel_global_obj *obj)
+{
+	int i;
+
+	for (i = 0; i < state->num_global_objs; i++)
+		if (obj == state->global_objs[i].ptr)
+			return state->global_objs[i].new_state;
+
+	return NULL;
+}
+
+void intel_atomic_swap_global_state(struct intel_atomic_state *state)
+{
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	struct intel_global_state *old_obj_state, *new_obj_state;
+	struct intel_global_obj *obj;
+	int i;
+
+	for_each_oldnew_global_obj_in_state(state, obj, old_obj_state,
+					    new_obj_state, i) {
+		WARN_ON(obj->state != old_obj_state);
+
+		/*
+		 * If the new state wasn't modified (and properly
+		 * locked for write access) we throw it away.
+		 */
+		if (!new_obj_state->changed)
+			continue;
+
+		assert_global_state_write_locked(dev_priv);
+
+		old_obj_state->state = state;
+		new_obj_state->state = NULL;
+
+		state->global_objs[i].state = old_obj_state;
+		obj->state = new_obj_state;
+	}
+}
+
+void intel_atomic_clear_global_state(struct intel_atomic_state *state)
+{
+	int i;
+
+	for (i = 0; i < state->num_global_objs; i++) {
+		struct intel_global_obj *obj = state->global_objs[i].ptr;
+
+		obj->funcs->atomic_destroy_state(obj,
+						 state->global_objs[i].state);
+		state->global_objs[i].ptr = NULL;
+		state->global_objs[i].state = NULL;
+		state->global_objs[i].old_state = NULL;
+		state->global_objs[i].new_state = NULL;
+	}
+	state->num_global_objs = 0;
+}
+
+int intel_atomic_lock_global_state(struct intel_global_state *obj_state)
+{
+	struct intel_atomic_state *state = obj_state->state;
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	struct intel_crtc *crtc;
+
+	for_each_intel_crtc(&dev_priv->drm, crtc) {
+		int ret;
+
+		ret = drm_modeset_lock(&crtc->base.mutex,
+				       state->base.acquire_ctx);
+		if (ret)
+			return ret;
+	}
+
+	obj_state->changed = true;
+
+	return 0;
+}
+
+int intel_atomic_serialize_global_state(struct intel_global_state *obj_state)
+{
+	struct intel_atomic_state *state = obj_state->state;
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	struct intel_crtc *crtc;
+
+	for_each_intel_crtc(&dev_priv->drm, crtc) {
+		struct intel_crtc_state *crtc_state;
+
+		crtc_state = intel_atomic_get_crtc_state(&state->base, crtc);
+		if (IS_ERR(crtc_state))
+			return PTR_ERR(crtc_state);
+	}
+
+	obj_state->changed = true;
+
+	return 0;
+}