1 /* SPDX-License-Identifier: MIT */
2 /*
3  * Copyright 2021 Advanced Micro Devices, Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  *
23  * Authors: AMD
24  *
25  */
26 
27 #ifndef __DC_LINK_DPIA_H__
28 #define __DC_LINK_DPIA_H__
29 
30 /* This module implements functionality for training DPIA links. */
31 
32 struct dc_link;
33 struct dc_link_settings;
34 
35 /* The approximate time (us) it takes to transmit 9 USB4 DP clock sync packets. */
36 #define DPIA_CLK_SYNC_DELAY 16000
37 
38 /* Extend interval between training status checks for manual testing. */
39 #define DPIA_DEBUG_EXTENDED_AUX_RD_INTERVAL_US 60000000
40 
41 /** @note Can remove once DP tunneling registers in upstream include/drm/drm_dp_helper.h */
42 /* DPCD DP Tunneling over USB4 */
43 #define DP_TUNNELING_CAPABILITIES_SUPPORT 0xe000d
44 #define DP_IN_ADAPTER_INFO                0xe000e
45 #define DP_USB4_DRIVER_ID                 0xe000f
46 #define DP_USB4_ROUTER_TOPOLOGY_ID        0xe001b
47 
48 /* SET_CONFIG message types sent by driver. */
49 enum dpia_set_config_type {
50 	DPIA_SET_CFG_SET_LINK = 0x01,
51 	DPIA_SET_CFG_SET_PHY_TEST_MODE = 0x05,
52 	DPIA_SET_CFG_SET_TRAINING = 0x18,
53 	DPIA_SET_CFG_SET_VSPE = 0x19
54 };
55 
56 /* Training stages (TS) in SET_CONFIG(SET_TRAINING) message. */
57 enum dpia_set_config_ts {
58 	DPIA_TS_DPRX_DONE = 0x00, /* Done training DPRX. */
59 	DPIA_TS_TPS1 = 0x01,
60 	DPIA_TS_TPS2 = 0x02,
61 	DPIA_TS_TPS3 = 0x03,
62 	DPIA_TS_TPS4 = 0x07,
63 	DPIA_TS_UFP_DONE = 0xff /* Done training DPTX-to-DPIA hop. */
64 };
65 
66 /* SET_CONFIG message data associated with messages sent by driver. */
67 union dpia_set_config_data {
68 	struct {
69 		uint8_t mode : 1;
70 		uint8_t reserved : 7;
71 	} set_link;
72 	struct {
73 		uint8_t stage;
74 	} set_training;
75 	struct {
76 		uint8_t swing : 2;
77 		uint8_t max_swing_reached : 1;
78 		uint8_t pre_emph : 2;
79 		uint8_t max_pre_emph_reached : 1;
80 		uint8_t reserved : 2;
81 	} set_vspe;
82 	uint8_t raw;
83 };
84 
85 /* Read tunneling device capability from DPCD and update link capability
86  * accordingly.
87  */
88 enum dc_status dpcd_get_tunneling_device_data(struct dc_link *link);
89 
90 /* Query hot plug status of USB4 DP tunnel.
91  * Returns true if HPD high.
92  */
93 bool dc_link_dpia_query_hpd_status(struct dc_link *link);
94 
95 /* Train DP tunneling link for USB4 DPIA display endpoint.
96  * DPIA equivalent of dc_link_dp_perfrorm_link_training.
97  * Aborts link training upon detection of sink unplug.
98  */
99 enum link_training_result dc_link_dpia_perform_link_training(
100 	struct dc_link *link,
101 	const struct link_resource *link_res,
102 	const struct dc_link_settings *link_setting,
103 	bool skip_video_pattern);
104 
105 #endif /* __DC_LINK_DPIA_H__ */
106