1 files changed, 93 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
new file mode 100644
index 000000000000..7c24d83f5c24
--- /dev/null
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2016-2019 Intel Corporation
+ */
+
+#ifndef _INTEL_GUC_CT_H_
+#define _INTEL_GUC_CT_H_
+
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+
+#include "intel_guc_fwif.h"
+
+struct i915_vma;
+struct intel_guc;
+
+/**
+ * DOC: Command Transport (CT).
+ *
+ * Buffer based command transport is a replacement for MMIO based mechanism.
+ * It can be used to perform both host-2-guc and guc-to-host communication.
+ */
+
+/** Represents single command transport buffer.
+ *
+ * A single command transport buffer consists of two parts, the header
+ * record (command transport buffer descriptor) and the actual buffer which
+ * holds the commands.
+ *
+ * @desc: pointer to the buffer descriptor
+ * @cmds: pointer to the commands buffer
+ */
+struct intel_guc_ct_buffer {
+	struct guc_ct_buffer_desc *desc;
+	u32 *cmds;
+};
+
+/** Represents pair of command transport buffers.
+ *
+ * Buffers go in pairs to allow bi-directional communication.
+ * To simplify the code we place both of them in the same vma.
+ * Buffers from the same pair must share unique owner id.
+ *
+ * @vma: pointer to the vma with pair of CT buffers
+ * @ctbs: buffers for sending(0) and receiving(1) commands
+ * @owner: unique identifier
+ * @next_fence: fence to be used with next send command
+ */
+struct intel_guc_ct_channel {
+	struct i915_vma *vma;
+	struct intel_guc_ct_buffer ctbs[2];
+	u32 owner;
+	u32 next_fence;
+	bool enabled;
+};
+
+/** Holds all command transport channels.
+ *
+ * @host_channel: main channel used by the host
+ */
+struct intel_guc_ct {
+	struct intel_guc_ct_channel host_channel;
+	/* other channels are tbd */
+
+	/** @lock: protects pending requests list */
+	spinlock_t lock;
+
+	/** @pending_requests: list of requests waiting for response */
+	struct list_head pending_requests;
+
+	/** @incoming_requests: list of incoming requests */
+	struct list_head incoming_requests;
+
+	/** @worker: worker for handling incoming requests */
+	struct work_struct worker;
+};
+
+void intel_guc_ct_init_early(struct intel_guc_ct *ct);
+int intel_guc_ct_init(struct intel_guc_ct *ct);
+void intel_guc_ct_fini(struct intel_guc_ct *ct);
+int intel_guc_ct_enable(struct intel_guc_ct *ct);
+void intel_guc_ct_disable(struct intel_guc_ct *ct);
+
+static inline void intel_guc_ct_stop(struct intel_guc_ct *ct)
+{
+	ct->host_channel.enabled = false;
+}
+
+int intel_guc_send_ct(struct intel_guc *guc, const u32 *action, u32 len,
+		      u32 *response_buf, u32 response_buf_size);
+void intel_guc_to_host_event_handler_ct(struct intel_guc *guc);
+
+#endif /* _INTEL_GUC_CT_H_ */