1/* SPDX-License-Identifier: MIT */
 2/*
 3 * Copyright © 2016-2019 Intel Corporation
 4 */
 5
 6#ifndef _INTEL_GUC_CT_H_
 7#define _INTEL_GUC_CT_H_
 8
 9#include <linux/interrupt.h>
10#include <linux/spinlock.h>
11#include <linux/workqueue.h>
12
13#include "intel_guc_fwif.h"
14
15struct i915_vma;
16struct intel_guc;
17
18/**
19 * DOC: Command Transport (CT).
20 *
21 * Buffer based command transport is a replacement for MMIO based mechanism.
22 * It can be used to perform both host-2-guc and guc-to-host communication.
23 */
24
25/** Represents single command transport buffer.
26 *
27 * A single command transport buffer consists of two parts, the header
28 * record (command transport buffer descriptor) and the actual buffer which
29 * holds the commands.
30 *
31 * @lock: protects access to the commands buffer and buffer descriptor
32 * @desc: pointer to the buffer descriptor
33 * @cmds: pointer to the commands buffer
34 * @size: size of the commands buffer
35 */
36struct intel_guc_ct_buffer {
37	spinlock_t lock;
38	struct guc_ct_buffer_desc *desc;
39	u32 *cmds;
40	u32 size;
41};
42
43
44/** Top-level structure for Command Transport related data
45 *
46 * Includes a pair of CT buffers for bi-directional communication and tracking
47 * for the H2G and G2H requests sent and received through the buffers.
48 */
49struct intel_guc_ct {
50	struct i915_vma *vma;
51	bool enabled;
52
53	/* buffers for sending and receiving commands */
54	struct {
55		struct intel_guc_ct_buffer send;
56		struct intel_guc_ct_buffer recv;
57	} ctbs;
58
59	struct tasklet_struct receive_tasklet;
60
61	struct {
62		u32 last_fence; /* last fence used to send request */
63
64		spinlock_t lock; /* protects pending requests list */
65		struct list_head pending; /* requests waiting for response */
66
67		struct list_head incoming; /* incoming requests */
68		struct work_struct worker; /* handler for incoming requests */
69	} requests;
70};
71
72void intel_guc_ct_init_early(struct intel_guc_ct *ct);
73int intel_guc_ct_init(struct intel_guc_ct *ct);
74void intel_guc_ct_fini(struct intel_guc_ct *ct);
75int intel_guc_ct_enable(struct intel_guc_ct *ct);
76void intel_guc_ct_disable(struct intel_guc_ct *ct);
77
78static inline void intel_guc_ct_sanitize(struct intel_guc_ct *ct)
79{
80	ct->enabled = false;
81}
82
83static inline bool intel_guc_ct_enabled(struct intel_guc_ct *ct)
84{
85	return ct->enabled;
86}
87
88int intel_guc_ct_send(struct intel_guc_ct *ct, const u32 *action, u32 len,
89		      u32 *response_buf, u32 response_buf_size);
90void intel_guc_ct_event_handler(struct intel_guc_ct *ct);
91
92#endif /* _INTEL_GUC_CT_H_ */