xref: /linux/drivers/gpu/drm/amd/pm/powerplay/hwmgr/pppcielanes.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 /*
2  * Copyright 2015 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  */
23 
24 #include <linux/types.h>
25 #include "atom-types.h"
26 #include "atombios.h"
27 #include "pppcielanes.h"
28 
29 /** \file
30  * Functions related to PCIe lane changes.
31  */
32 
33 /* For converting from number of lanes to lane bits.  */
34 static const unsigned char pp_r600_encode_lanes[] = {
35 	0,          /*  0 Not Supported  */
36 	1,          /*  1 Lane  */
37 	2,          /*  2 Lanes  */
38 	0,          /*  3 Not Supported  */
39 	3,          /*  4 Lanes  */
40 	0,          /*  5 Not Supported  */
41 	0,          /*  6 Not Supported  */
42 	0,          /*  7 Not Supported  */
43 	4,          /*  8 Lanes  */
44 	0,          /*  9 Not Supported  */
45 	0,          /* 10 Not Supported  */
46 	0,          /* 11 Not Supported  */
47 	5,          /* 12 Lanes (Not actually supported)  */
48 	0,          /* 13 Not Supported  */
49 	0,          /* 14 Not Supported  */
50 	0,          /* 15 Not Supported  */
51 	6           /* 16 Lanes  */
52 };
53 
54 static const unsigned char pp_r600_decoded_lanes[8] = { 16, 1, 2, 4, 8, 12, 16, };
55 
56 uint8_t encode_pcie_lane_width(uint32_t num_lanes)
57 {
58 	return pp_r600_encode_lanes[num_lanes];
59 }
60 
61 uint8_t decode_pcie_lane_width(uint32_t num_lanes)
62 {
63 	return pp_r600_decoded_lanes[num_lanes];
64 }
65