1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * System Control and Management Interface (SCMI) Message Protocol 4 * driver common header file containing some definitions, structures 5 * and function prototypes used in all the different SCMI protocols. 6 * 7 * Copyright (C) 2018 ARM Ltd. 8 */ 9 #ifndef _SCMI_COMMON_H 10 #define _SCMI_COMMON_H 11 12 #include <linux/bitfield.h> 13 #include <linux/completion.h> 14 #include <linux/device.h> 15 #include <linux/errno.h> 16 #include <linux/kernel.h> 17 #include <linux/scmi_protocol.h> 18 #include <linux/types.h> 19 20 #include <asm/unaligned.h> 21 22 #define PROTOCOL_REV_MINOR_MASK GENMASK(15, 0) 23 #define PROTOCOL_REV_MAJOR_MASK GENMASK(31, 16) 24 #define PROTOCOL_REV_MAJOR(x) (u16)(FIELD_GET(PROTOCOL_REV_MAJOR_MASK, (x))) 25 #define PROTOCOL_REV_MINOR(x) (u16)(FIELD_GET(PROTOCOL_REV_MINOR_MASK, (x))) 26 #define MAX_PROTOCOLS_IMP 16 27 #define MAX_OPPS 16 28 29 enum scmi_common_cmd { 30 PROTOCOL_VERSION = 0x0, 31 PROTOCOL_ATTRIBUTES = 0x1, 32 PROTOCOL_MESSAGE_ATTRIBUTES = 0x2, 33 }; 34 35 /** 36 * struct scmi_msg_resp_prot_version - Response for a message 37 * 38 * @minor_version: Minor version of the ABI that firmware supports 39 * @major_version: Major version of the ABI that firmware supports 40 * 41 * In general, ABI version changes follow the rule that minor version increments 42 * are backward compatible. Major revision changes in ABI may not be 43 * backward compatible. 44 * 45 * Response to a generic message with message type SCMI_MSG_VERSION 46 */ 47 struct scmi_msg_resp_prot_version { 48 __le16 minor_version; 49 __le16 major_version; 50 }; 51 52 #define MSG_ID_MASK GENMASK(7, 0) 53 #define MSG_XTRACT_ID(hdr) FIELD_GET(MSG_ID_MASK, (hdr)) 54 #define MSG_TYPE_MASK GENMASK(9, 8) 55 #define MSG_XTRACT_TYPE(hdr) FIELD_GET(MSG_TYPE_MASK, (hdr)) 56 #define MSG_TYPE_COMMAND 0 57 #define MSG_TYPE_DELAYED_RESP 2 58 #define MSG_TYPE_NOTIFICATION 3 59 #define MSG_PROTOCOL_ID_MASK GENMASK(17, 10) 60 #define MSG_XTRACT_PROT_ID(hdr) FIELD_GET(MSG_PROTOCOL_ID_MASK, (hdr)) 61 #define MSG_TOKEN_ID_MASK GENMASK(27, 18) 62 #define MSG_XTRACT_TOKEN(hdr) FIELD_GET(MSG_TOKEN_ID_MASK, (hdr)) 63 #define MSG_TOKEN_MAX (MSG_XTRACT_TOKEN(MSG_TOKEN_ID_MASK) + 1) 64 65 /** 66 * struct scmi_msg_hdr - Message(Tx/Rx) header 67 * 68 * @id: The identifier of the message being sent 69 * @protocol_id: The identifier of the protocol used to send @id message 70 * @seq: The token to identify the message. When a message returns, the 71 * platform returns the whole message header unmodified including the 72 * token 73 * @status: Status of the transfer once it's complete 74 * @poll_completion: Indicate if the transfer needs to be polled for 75 * completion or interrupt mode is used 76 */ 77 struct scmi_msg_hdr { 78 u8 id; 79 u8 protocol_id; 80 u16 seq; 81 u32 status; 82 bool poll_completion; 83 }; 84 85 /** 86 * pack_scmi_header() - packs and returns 32-bit header 87 * 88 * @hdr: pointer to header containing all the information on message id, 89 * protocol id and sequence id. 90 * 91 * Return: 32-bit packed message header to be sent to the platform. 92 */ 93 static inline u32 pack_scmi_header(struct scmi_msg_hdr *hdr) 94 { 95 return FIELD_PREP(MSG_ID_MASK, hdr->id) | 96 FIELD_PREP(MSG_TOKEN_ID_MASK, hdr->seq) | 97 FIELD_PREP(MSG_PROTOCOL_ID_MASK, hdr->protocol_id); 98 } 99 100 /** 101 * unpack_scmi_header() - unpacks and records message and protocol id 102 * 103 * @msg_hdr: 32-bit packed message header sent from the platform 104 * @hdr: pointer to header to fetch message and protocol id. 105 */ 106 static inline void unpack_scmi_header(u32 msg_hdr, struct scmi_msg_hdr *hdr) 107 { 108 hdr->id = MSG_XTRACT_ID(msg_hdr); 109 hdr->protocol_id = MSG_XTRACT_PROT_ID(msg_hdr); 110 } 111 112 /** 113 * struct scmi_msg - Message(Tx/Rx) structure 114 * 115 * @buf: Buffer pointer 116 * @len: Length of data in the Buffer 117 */ 118 struct scmi_msg { 119 void *buf; 120 size_t len; 121 }; 122 123 /** 124 * struct scmi_xfer - Structure representing a message flow 125 * 126 * @transfer_id: Unique ID for debug & profiling purpose 127 * @hdr: Transmit message header 128 * @tx: Transmit message 129 * @rx: Receive message, the buffer should be pre-allocated to store 130 * message. If request-ACK protocol is used, we can reuse the same 131 * buffer for the rx path as we use for the tx path. 132 * @done: command message transmit completion event 133 * @async_done: pointer to delayed response message received event completion 134 */ 135 struct scmi_xfer { 136 int transfer_id; 137 struct scmi_msg_hdr hdr; 138 struct scmi_msg tx; 139 struct scmi_msg rx; 140 struct completion done; 141 struct completion *async_done; 142 }; 143 144 void scmi_xfer_put(const struct scmi_handle *h, struct scmi_xfer *xfer); 145 int scmi_do_xfer(const struct scmi_handle *h, struct scmi_xfer *xfer); 146 int scmi_do_xfer_with_response(const struct scmi_handle *h, 147 struct scmi_xfer *xfer); 148 int scmi_xfer_get_init(const struct scmi_handle *h, u8 msg_id, u8 prot_id, 149 size_t tx_size, size_t rx_size, struct scmi_xfer **p); 150 void scmi_reset_rx_to_maxsz(const struct scmi_handle *handle, 151 struct scmi_xfer *xfer); 152 int scmi_handle_put(const struct scmi_handle *handle); 153 struct scmi_handle *scmi_handle_get(struct device *dev); 154 void scmi_set_handle(struct scmi_device *scmi_dev); 155 int scmi_version_get(const struct scmi_handle *h, u8 protocol, u32 *version); 156 void scmi_setup_protocol_implemented(const struct scmi_handle *handle, 157 u8 *prot_imp); 158 159 int scmi_base_protocol_init(struct scmi_handle *h); 160 161 int __init scmi_bus_init(void); 162 void __exit scmi_bus_exit(void); 163 164 #define DECLARE_SCMI_REGISTER_UNREGISTER(func) \ 165 int __init scmi_##func##_register(void); \ 166 void __exit scmi_##func##_unregister(void) 167 DECLARE_SCMI_REGISTER_UNREGISTER(clock); 168 DECLARE_SCMI_REGISTER_UNREGISTER(perf); 169 DECLARE_SCMI_REGISTER_UNREGISTER(power); 170 DECLARE_SCMI_REGISTER_UNREGISTER(reset); 171 DECLARE_SCMI_REGISTER_UNREGISTER(sensors); 172 DECLARE_SCMI_REGISTER_UNREGISTER(voltage); 173 DECLARE_SCMI_REGISTER_UNREGISTER(system); 174 175 #define DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(id, name) \ 176 int __init scmi_##name##_register(void) \ 177 { \ 178 return scmi_protocol_register((id), &scmi_##name##_protocol_init); \ 179 } \ 180 \ 181 void __exit scmi_##name##_unregister(void) \ 182 { \ 183 scmi_protocol_unregister((id)); \ 184 } 185 186 /* SCMI Transport */ 187 /** 188 * struct scmi_chan_info - Structure representing a SCMI channel information 189 * 190 * @dev: Reference to device in the SCMI hierarchy corresponding to this 191 * channel 192 * @handle: Pointer to SCMI entity handle 193 * @transport_info: Transport layer related information 194 */ 195 struct scmi_chan_info { 196 struct device *dev; 197 struct scmi_handle *handle; 198 void *transport_info; 199 }; 200 201 /** 202 * struct scmi_transport_ops - Structure representing a SCMI transport ops 203 * 204 * @chan_available: Callback to check if channel is available or not 205 * @chan_setup: Callback to allocate and setup a channel 206 * @chan_free: Callback to free a channel 207 * @send_message: Callback to send a message 208 * @mark_txdone: Callback to mark tx as done 209 * @fetch_response: Callback to fetch response 210 * @fetch_notification: Callback to fetch notification 211 * @clear_channel: Callback to clear a channel 212 * @poll_done: Callback to poll transfer status 213 */ 214 struct scmi_transport_ops { 215 bool (*chan_available)(struct device *dev, int idx); 216 int (*chan_setup)(struct scmi_chan_info *cinfo, struct device *dev, 217 bool tx); 218 int (*chan_free)(int id, void *p, void *data); 219 int (*send_message)(struct scmi_chan_info *cinfo, 220 struct scmi_xfer *xfer); 221 void (*mark_txdone)(struct scmi_chan_info *cinfo, int ret); 222 void (*fetch_response)(struct scmi_chan_info *cinfo, 223 struct scmi_xfer *xfer); 224 void (*fetch_notification)(struct scmi_chan_info *cinfo, 225 size_t max_len, struct scmi_xfer *xfer); 226 void (*clear_channel)(struct scmi_chan_info *cinfo); 227 bool (*poll_done)(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer); 228 }; 229 230 /** 231 * struct scmi_desc - Description of SoC integration 232 * 233 * @ops: Pointer to the transport specific ops structure 234 * @max_rx_timeout_ms: Timeout for communication with SoC (in Milliseconds) 235 * @max_msg: Maximum number of messages that can be pending 236 * simultaneously in the system 237 * @max_msg_size: Maximum size of data per message that can be handled. 238 */ 239 struct scmi_desc { 240 const struct scmi_transport_ops *ops; 241 int max_rx_timeout_ms; 242 int max_msg; 243 int max_msg_size; 244 }; 245 246 extern const struct scmi_desc scmi_mailbox_desc; 247 #ifdef CONFIG_HAVE_ARM_SMCCC 248 extern const struct scmi_desc scmi_smc_desc; 249 #endif 250 251 void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr); 252 void scmi_free_channel(struct scmi_chan_info *cinfo, struct idr *idr, int id); 253 254 /* shmem related declarations */ 255 struct scmi_shared_mem; 256 257 void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem, 258 struct scmi_xfer *xfer); 259 u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem); 260 void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem, 261 struct scmi_xfer *xfer); 262 void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem, 263 size_t max_len, struct scmi_xfer *xfer); 264 void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem); 265 bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem, 266 struct scmi_xfer *xfer); 267 268 #endif /* _SCMI_COMMON_H */ 269