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/spinlock.h>
10 #include <linux/workqueue.h>
11
12 #include "intel_guc_fwif.h"
13
14 struct i915_vma;
15 struct intel_guc;
16
17 /**
18 * DOC: Command Transport (CT).
19 *
20 * Buffer based command transport is a replacement for MMIO based mechanism.
21 * It can be used to perform both host-2-guc and guc-to-host communication.
22 */
23
24 /** Represents single command transport buffer.
25 *
26 * A single command transport buffer consists of two parts, the header
27 * record (command transport buffer descriptor) and the actual buffer which
28 * holds the commands.
29 *
30 * @desc: pointer to the buffer descriptor
31 * @cmds: pointer to the commands buffer
32 */
33 struct intel_guc_ct_buffer {
34 struct guc_ct_buffer_desc *desc;
35 u32 *cmds;
36 };
37
38 /** Represents pair of command transport buffers.
39 *
40 * Buffers go in pairs to allow bi-directional communication.
41 * To simplify the code we place both of them in the same vma.
42 * Buffers from the same pair must share unique owner id.
43 *
44 * @vma: pointer to the vma with pair of CT buffers
45 * @ctbs: buffers for sending(0) and receiving(1) commands
46 * @owner: unique identifier
47 * @next_fence: fence to be used with next send command
48 */
49 struct intel_guc_ct_channel {
50 struct i915_vma *vma;
51 struct intel_guc_ct_buffer ctbs[2];
52 u32 owner;
53 u32 next_fence;
54 bool enabled;
55 };
56
57 /** Holds all command transport channels.
58 *
59 * @host_channel: main channel used by the host
60 */
61 struct intel_guc_ct {
62 struct intel_guc_ct_channel host_channel;
63 /* other channels are tbd */
64
65 /** @lock: protects pending requests list */
66 spinlock_t lock;
67
68 /** @pending_requests: list of requests waiting for response */
69 struct list_head pending_requests;
70
71 /** @incoming_requests: list of incoming requests */
72 struct list_head incoming_requests;
73
74 /** @worker: worker for handling incoming requests */
75 struct work_struct worker;
76 };
77
78 void intel_guc_ct_init_early(struct intel_guc_ct *ct);
79 int intel_guc_ct_init(struct intel_guc_ct *ct);
80 void intel_guc_ct_fini(struct intel_guc_ct *ct);
81 int intel_guc_ct_enable(struct intel_guc_ct *ct);
82 void intel_guc_ct_disable(struct intel_guc_ct *ct);
83
84 static inline void intel_guc_ct_stop(struct intel_guc_ct *ct)
85 {
86 ct->host_channel.enabled = false;
87 }
88
89 int intel_guc_send_ct(struct intel_guc *guc, const u32 *action, u32 len,
90 u32 *response_buf, u32 response_buf_size);
91 void intel_guc_to_host_event_handler_ct(struct intel_guc *guc);
92
93 #endif /* _INTEL_GUC_CT_H_ */