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 10 #include <linux/bitfield.h> 11 #include <linux/completion.h> 12 #include <linux/device.h> 13 #include <linux/errno.h> 14 #include <linux/kernel.h> 15 #include <linux/scmi_protocol.h> 16 #include <linux/types.h> 17 18 #define PROTOCOL_REV_MINOR_MASK GENMASK(15, 0) 19 #define PROTOCOL_REV_MAJOR_MASK GENMASK(31, 16) 20 #define PROTOCOL_REV_MAJOR(x) (u16)(FIELD_GET(PROTOCOL_REV_MAJOR_MASK, (x))) 21 #define PROTOCOL_REV_MINOR(x) (u16)(FIELD_GET(PROTOCOL_REV_MINOR_MASK, (x))) 22 #define MAX_PROTOCOLS_IMP 16 23 #define MAX_OPPS 16 24 25 enum scmi_common_cmd { 26 PROTOCOL_VERSION = 0x0, 27 PROTOCOL_ATTRIBUTES = 0x1, 28 PROTOCOL_MESSAGE_ATTRIBUTES = 0x2, 29 }; 30 31 /** 32 * struct scmi_msg_resp_prot_version - Response for a message 33 * 34 * @major_version: Major version of the ABI that firmware supports 35 * @minor_version: Minor version of the ABI that firmware supports 36 * 37 * In general, ABI version changes follow the rule that minor version increments 38 * are backward compatible. Major revision changes in ABI may not be 39 * backward compatible. 40 * 41 * Response to a generic message with message type SCMI_MSG_VERSION 42 */ 43 struct scmi_msg_resp_prot_version { 44 __le16 minor_version; 45 __le16 major_version; 46 }; 47 48 /** 49 * struct scmi_msg_hdr - Message(Tx/Rx) header 50 * 51 * @id: The identifier of the command being sent 52 * @protocol_id: The identifier of the protocol used to send @id command 53 * @seq: The token to identify the message. when a message/command returns, 54 * the platform returns the whole message header unmodified including 55 * the token 56 * @status: Status of the transfer once it's complete 57 * @poll_completion: Indicate if the transfer needs to be polled for 58 * completion or interrupt mode is used 59 */ 60 struct scmi_msg_hdr { 61 u8 id; 62 u8 protocol_id; 63 u16 seq; 64 u32 status; 65 bool poll_completion; 66 }; 67 68 /** 69 * struct scmi_msg - Message(Tx/Rx) structure 70 * 71 * @buf: Buffer pointer 72 * @len: Length of data in the Buffer 73 */ 74 struct scmi_msg { 75 void *buf; 76 size_t len; 77 }; 78 79 /** 80 * struct scmi_xfer - Structure representing a message flow 81 * 82 * @hdr: Transmit message header 83 * @tx: Transmit message 84 * @rx: Receive message, the buffer should be pre-allocated to store 85 * message. If request-ACK protocol is used, we can reuse the same 86 * buffer for the rx path as we use for the tx path. 87 * @done: completion event 88 */ 89 struct scmi_xfer { 90 struct scmi_msg_hdr hdr; 91 struct scmi_msg tx; 92 struct scmi_msg rx; 93 struct completion done; 94 }; 95 96 void scmi_xfer_put(const struct scmi_handle *h, struct scmi_xfer *xfer); 97 int scmi_do_xfer(const struct scmi_handle *h, struct scmi_xfer *xfer); 98 int scmi_xfer_get_init(const struct scmi_handle *h, u8 msg_id, u8 prot_id, 99 size_t tx_size, size_t rx_size, struct scmi_xfer **p); 100 int scmi_handle_put(const struct scmi_handle *handle); 101 struct scmi_handle *scmi_handle_get(struct device *dev); 102 void scmi_set_handle(struct scmi_device *scmi_dev); 103 int scmi_version_get(const struct scmi_handle *h, u8 protocol, u32 *version); 104 void scmi_setup_protocol_implemented(const struct scmi_handle *handle, 105 u8 *prot_imp); 106 107 int scmi_base_protocol_init(struct scmi_handle *h); 108