features.h

  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
 12typedef 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 */
 22static_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 */
 36struct 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 */
 71struct 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 */
 99struct 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 */
121struct 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 */
131enum 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 */
153struct 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 */
167enum 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