1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * Copyright (c) 2024,2025, Intel Corporation
4  *
5  * These are definitions for the mailbox command interface of CXL subsystem.
6  */
7 #ifndef _UAPI_CXL_FEATURES_H_
8 #define _UAPI_CXL_FEATURES_H_
9 
10 #include <linux/types.h>
11 
12 typedef unsigned char __uapi_uuid_t[16];
13 
14 #ifdef __KERNEL__
15 #include <linux/uuid.h>
16 /*
17  * Note, __uapi_uuid_t is 1-byte aligned on modern compilers and 4-byte
18  * aligned on others. Ensure that __uapi_uuid_t in a struct is placed at
19  * a 4-byte aligned offset, or the structure is packed, to ensure
20  * consistent padding.
21  */
22 static_assert(sizeof(__uapi_uuid_t) == sizeof(uuid_t));
23 #define __uapi_uuid_t uuid_t
24 #endif
25 
26 /*
27  * struct cxl_mbox_get_sup_feats_in - Get Supported Features input
28  *
29  * @count: bytes of Feature data to return in output
30  * @start_idx: index of first requested Supported Feature Entry, 0 based.
31  * @reserved: reserved field, must be 0s.
32  *
33  * Get Supported Features (0x500h) CXL r3.2 8.2.9.6.1 command.
34  * Input block for Get support Feature
35  */
36 struct cxl_mbox_get_sup_feats_in {
37 	__le32 count;
38 	__le16 start_idx;
39 	__u8 reserved[2];
40 } __attribute__ ((__packed__));
41 
42 /* CXL spec r3.2 Table 8-87 command effects */
43 #define CXL_CMD_CONFIG_CHANGE_COLD_RESET	BIT(0)
44 #define CXL_CMD_CONFIG_CHANGE_IMMEDIATE		BIT(1)
45 #define CXL_CMD_DATA_CHANGE_IMMEDIATE		BIT(2)
46 #define CXL_CMD_POLICY_CHANGE_IMMEDIATE		BIT(3)
47 #define CXL_CMD_LOG_CHANGE_IMMEDIATE		BIT(4)
48 #define CXL_CMD_SECURITY_STATE_CHANGE		BIT(5)
49 #define CXL_CMD_BACKGROUND			BIT(6)
50 #define CXL_CMD_BGCMD_ABORT_SUPPORTED		BIT(7)
51 #define CXL_CMD_EFFECTS_VALID			BIT(9)
52 #define CXL_CMD_CONFIG_CHANGE_CONV_RESET	BIT(10)
53 #define CXL_CMD_CONFIG_CHANGE_CXL_RESET		BIT(11)
54 #define CXL_CMD_EFFECTS_RESERVED		GENMASK(15, 12)
55 
56 /*
57  * struct cxl_feat_entry - Supported Feature Entry
58  * @uuid: UUID of the Feature
59  * @id: id to identify the feature. 0 based
60  * @get_feat_size: max bytes required for Get Feature command for this Feature
61  * @set_feat_size: max bytes required for Set Feature command for this Feature
62  * @flags: attribute flags
63  * @get_feat_ver: Get Feature version
64  * @set_feat_ver: Set Feature version
65  * @effects: Set Feature command effects
66  * @reserved: reserved, must be 0
67  *
68  * CXL spec r3.2 Table 8-109
69  * Get Supported Features Supported Feature Entry
70  */
71 struct cxl_feat_entry {
72 	__uapi_uuid_t uuid;
73 	__le16 id;
74 	__le16 get_feat_size;
75 	__le16 set_feat_size;
76 	__le32 flags;
77 	__u8 get_feat_ver;
78 	__u8 set_feat_ver;
79 	__le16 effects;
80 	__u8 reserved[18];
81 } __attribute__ ((__packed__));
82 
83 /* @flags field for 'struct cxl_feat_entry' */
84 #define CXL_FEATURE_F_CHANGEABLE		BIT(0)
85 #define CXL_FEATURE_F_PERSIST_FW_UPDATE		BIT(4)
86 #define CXL_FEATURE_F_DEFAULT_SEL		BIT(5)
87 #define CXL_FEATURE_F_SAVED_SEL			BIT(6)
88 
89 /*
90  * struct cxl_mbox_get_sup_feats_out - Get Supported Features output
91  * @num_entries: number of Supported Feature Entries returned
92  * @supported_feats: number of supported Features
93  * @reserved: reserved, must be 0s.
94  * @ents: Supported Feature Entries array
95  *
96  * CXL spec r3.2 Table 8-108
97  * Get supported Features Output Payload
98  */
99 struct cxl_mbox_get_sup_feats_out {
100 	__struct_group(cxl_mbox_get_sup_feats_out_hdr, hdr, /* no attrs */,
101 		__le16 num_entries;
102 		__le16 supported_feats;
103 		__u8 reserved[4];
104 	);
105 	struct cxl_feat_entry ents[] __counted_by_le(num_entries);
106 } __attribute__ ((__packed__));
107 
108 /*
109  * Get Feature CXL spec r3.2 Spec 8.2.9.6.2
110  */
111 
112 /*
113  * struct cxl_mbox_get_feat_in - Get Feature input
114  * @uuid: UUID for Feature
115  * @offset: offset of the first byte in Feature data for output payload
116  * @count: count in bytes of Feature data returned
117  * @selection: 0 current value, 1 default value, 2 saved value
118  *
119  * CXL spec r3.2 section 8.2.9.6.2 Table 8-99
120  */
121 struct cxl_mbox_get_feat_in {
122 	__uapi_uuid_t uuid;
123 	__le16 offset;
124 	__le16 count;
125 	__u8 selection;
126 } __attribute__ ((__packed__));
127 
128 /*
129  * enum cxl_get_feat_selection - selection field of Get Feature input
130  */
131 enum cxl_get_feat_selection {
132 	CXL_GET_FEAT_SEL_CURRENT_VALUE,
133 	CXL_GET_FEAT_SEL_DEFAULT_VALUE,
134 	CXL_GET_FEAT_SEL_SAVED_VALUE,
135 	CXL_GET_FEAT_SEL_MAX
136 };
137 
138 /*
139  * Set Feature CXL spec r3.2  8.2.9.6.3
140  */
141 
142 /*
143  * struct cxl_mbox_set_feat_in - Set Features input
144  * @uuid: UUID for Feature
145  * @flags: set feature flags
146  * @offset: byte offset of Feature data to update
147  * @version: Feature version of the data in Feature Data
148  * @rsvd: reserved, must be 0s.
149  * @feat_data: raw byte stream of Features data to update
150  *
151  * CXL spec r3.2 section 8.2.9.6.3 Table 8-101
152  */
153 struct cxl_mbox_set_feat_in {
154 	__struct_group(cxl_mbox_set_feat_hdr, hdr, /* no attrs */,
155 		__uapi_uuid_t uuid;
156 		__le32 flags;
157 		__le16 offset;
158 		__u8 version;
159 		__u8 rsvd[9];
160 	);
161 	__u8 feat_data[];
162 }  __packed;
163 
164 /*
165  * enum cxl_set_feat_flag_data_transfer - Set Feature flags field
166  */
167 enum cxl_set_feat_flag_data_transfer {
168 	CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER = 0,
169 	CXL_SET_FEAT_FLAG_INITIATE_DATA_TRANSFER,
170 	CXL_SET_FEAT_FLAG_CONTINUE_DATA_TRANSFER,
171 	CXL_SET_FEAT_FLAG_FINISH_DATA_TRANSFER,
172 	CXL_SET_FEAT_FLAG_ABORT_DATA_TRANSFER,
173 	CXL_SET_FEAT_FLAG_DATA_TRANSFER_MAX
174 };
175 
176 #define CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK		GENMASK(2, 0)
177 #define CXL_SET_FEAT_FLAG_DATA_SAVED_ACROSS_RESET	BIT(3)
178 
179 #endif
180