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 #ifndef __AMD_PCIE_HELPERS_H__
24 #define __AMD_PCIE_HELPERS_H__
25
26 #include "amd_pcie.h"
27
28 static inline bool is_pcie_gen3_supported(uint32_t pcie_link_speed_cap)
29 {
30 if (pcie_link_speed_cap & CAIL_PCIE_LINK_SPEED_SUPPORT_GEN3)
31 return true;
32
33 return false;
34 }
35
36 static inline bool is_pcie_gen2_supported(uint32_t pcie_link_speed_cap)
37 {
38 if (pcie_link_speed_cap & CAIL_PCIE_LINK_SPEED_SUPPORT_GEN2)
39 return true;
40
41 return false;
42 }
43
44 /* Get the new PCIE speed given the ASIC PCIE Cap and the NewState's requested PCIE speed*/
45 static inline uint16_t get_pcie_gen_support(uint32_t pcie_link_speed_cap,
46 uint16_t ns_pcie_gen)
47 {
48 uint32_t asic_pcie_link_speed_cap = (pcie_link_speed_cap &
49 CAIL_ASIC_PCIE_LINK_SPEED_SUPPORT_MASK);
50 uint32_t sys_pcie_link_speed_cap = (pcie_link_speed_cap &
51 CAIL_PCIE_LINK_SPEED_SUPPORT_MASK);
52
53 switch (asic_pcie_link_speed_cap) {
54 case CAIL_ASIC_PCIE_LINK_SPEED_SUPPORT_GEN1:
55 return PP_PCIEGen1;
56
57 case CAIL_ASIC_PCIE_LINK_SPEED_SUPPORT_GEN2:
58 return PP_PCIEGen2;
59
60 case CAIL_ASIC_PCIE_LINK_SPEED_SUPPORT_GEN3:
61 return PP_PCIEGen3;
62
63 default:
64 if (is_pcie_gen3_supported(sys_pcie_link_speed_cap) &&
65 (ns_pcie_gen == PP_PCIEGen3)) {
66 return PP_PCIEGen3;
67 } else if (is_pcie_gen2_supported(sys_pcie_link_speed_cap) &&
68 ((ns_pcie_gen == PP_PCIEGen3) || (ns_pcie_gen == PP_PCIEGen2))) {
69 return PP_PCIEGen2;
70 }
71 }
72
73 return PP_PCIEGen1;
74 }
75
76 static inline uint16_t get_pcie_lane_support(uint32_t pcie_lane_width_cap,
77 uint16_t ns_pcie_lanes)
78 {
79 int i, j;
80 uint16_t new_pcie_lanes = ns_pcie_lanes;
81 uint16_t pcie_lanes[7] = {1, 2, 4, 8, 12, 16, 32};
82
83 switch (pcie_lane_width_cap) {
84 case 0:
85 pr_err("No valid PCIE lane width reported\n");
86 break;
87 case CAIL_PCIE_LINK_WIDTH_SUPPORT_X1:
88 new_pcie_lanes = 1;
89 break;
90 case CAIL_PCIE_LINK_WIDTH_SUPPORT_X2:
91 new_pcie_lanes = 2;
92 break;
93 case CAIL_PCIE_LINK_WIDTH_SUPPORT_X4:
94 new_pcie_lanes = 4;
95 break;
96 case CAIL_PCIE_LINK_WIDTH_SUPPORT_X8:
97 new_pcie_lanes = 8;
98 break;
99 case CAIL_PCIE_LINK_WIDTH_SUPPORT_X12:
100 new_pcie_lanes = 12;
101 break;
102 case CAIL_PCIE_LINK_WIDTH_SUPPORT_X16:
103 new_pcie_lanes = 16;
104 break;
105 case CAIL_PCIE_LINK_WIDTH_SUPPORT_X32:
106 new_pcie_lanes = 32;
107 break;
108 default:
109 for (i = 0; i < 7; i++) {
110 if (ns_pcie_lanes == pcie_lanes[i]) {
111 if (pcie_lane_width_cap & (0x10000 << i)) {
112 break;
113 } else {
114 for (j = i - 1; j >= 0; j--) {
115 if (pcie_lane_width_cap & (0x10000 << j)) {
116 new_pcie_lanes = pcie_lanes[j];
117 break;
118 }
119 }
120
121 if (j < 0) {
122 for (j = i + 1; j < 7; j++) {
123 if (pcie_lane_width_cap & (0x10000 << j)) {
124 new_pcie_lanes = pcie_lanes[j];
125 break;
126 }
127 }
128 if (j > 7)
129 pr_err("Cannot find a valid PCIE lane width!\n");
130 }
131 }
132 break;
133 }
134 }
135 break;
136 }
137
138 return new_pcie_lanes;
139 }
140
141 #endif