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 
39 /** Top-level structure for Command Transport related data
40  *
41  * Includes a pair of CT buffers for bi-directional communication and tracking
42  * for the H2G and G2H requests sent and received through the buffers.
43  */
44 struct intel_guc_ct {
45 	struct i915_vma *vma;
46 	bool enabled;
47 
48 	/* buffers for sending(0) and receiving(1) commands */
49 	struct intel_guc_ct_buffer ctbs[2];
50 
51 	struct {
52 		u32 next_fence; /* fence to be used with next request to send */
53 
54 		spinlock_t lock; /* protects pending requests list */
55 		struct list_head pending; /* requests waiting for response */
56 
57 		struct list_head incoming; /* incoming requests */
58 		struct work_struct worker; /* handler for incoming requests */
59 	} requests;
60 };
61 
62 void intel_guc_ct_init_early(struct intel_guc_ct *ct);
63 int intel_guc_ct_init(struct intel_guc_ct *ct);
64 void intel_guc_ct_fini(struct intel_guc_ct *ct);
65 int intel_guc_ct_enable(struct intel_guc_ct *ct);
66 void intel_guc_ct_disable(struct intel_guc_ct *ct);
67 
68 static inline bool intel_guc_ct_enabled(struct intel_guc_ct *ct)
69 {
70 	return ct->enabled;
71 }
72 
73 int intel_guc_ct_send(struct intel_guc_ct *ct, const u32 *action, u32 len,
74 		      u32 *response_buf, u32 response_buf_size);
75 void intel_guc_ct_event_handler(struct intel_guc_ct *ct);
76 
77 #endif /* _INTEL_GUC_CT_H_ */
78