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/completion.h> 11 #include <linux/device.h> 12 #include <linux/errno.h> 13 #include <linux/kernel.h> 14 #include <linux/scmi_protocol.h> 15 #include <linux/types.h> 16 17 #define PROTOCOL_REV_MINOR_BITS 16 18 #define PROTOCOL_REV_MINOR_MASK ((1U << PROTOCOL_REV_MINOR_BITS) - 1) 19 #define PROTOCOL_REV_MAJOR(x) ((x) >> PROTOCOL_REV_MINOR_BITS) 20 #define PROTOCOL_REV_MINOR(x) ((x) & PROTOCOL_REV_MINOR_MASK) 21 #define MAX_PROTOCOLS_IMP 16 22 #define MAX_OPPS 16 23 24 enum scmi_common_cmd { 25 PROTOCOL_VERSION = 0x0, 26 PROTOCOL_ATTRIBUTES = 0x1, 27 PROTOCOL_MESSAGE_ATTRIBUTES = 0x2, 28 }; 29 30 /** 31 * struct scmi_msg_resp_prot_version - Response for a message 32 * 33 * @major_version: Major version of the ABI that firmware supports 34 * @minor_version: Minor version of the ABI that firmware supports 35 * 36 * In general, ABI version changes follow the rule that minor version increments 37 * are backward compatible. Major revision changes in ABI may not be 38 * backward compatible. 39 * 40 * Response to a generic message with message type SCMI_MSG_VERSION 41 */ 42 struct scmi_msg_resp_prot_version { 43 __le16 minor_version; 44 __le16 major_version; 45 }; 46 47 /** 48 * struct scmi_msg_hdr - Message(Tx/Rx) header 49 * 50 * @id: The identifier of the command being sent 51 * @protocol_id: The identifier of the protocol used to send @id command 52 * @seq: The token to identify the message. when a message/command returns, 53 * the platform returns the whole message header unmodified including 54 * the token. 55 */ 56 struct scmi_msg_hdr { 57 u8 id; 58 u8 protocol_id; 59 u16 seq; 60 u32 status; 61 bool poll_completion; 62 }; 63 64 /** 65 * struct scmi_msg - Message(Tx/Rx) structure 66 * 67 * @buf: Buffer pointer 68 * @len: Length of data in the Buffer 69 */ 70 struct scmi_msg { 71 void *buf; 72 size_t len; 73 }; 74 75 /** 76 * struct scmi_xfer - Structure representing a message flow 77 * 78 * @hdr: Transmit message header 79 * @tx: Transmit message 80 * @rx: Receive message, the buffer should be pre-allocated to store 81 * message. If request-ACK protocol is used, we can reuse the same 82 * buffer for the rx path as we use for the tx path. 83 * @done: completion event 84 */ 85 86 struct scmi_xfer { 87 void *con_priv; 88 struct scmi_msg_hdr hdr; 89 struct scmi_msg tx; 90 struct scmi_msg rx; 91 struct completion done; 92 }; 93 94 void scmi_one_xfer_put(const struct scmi_handle *h, struct scmi_xfer *xfer); 95 int scmi_do_xfer(const struct scmi_handle *h, struct scmi_xfer *xfer); 96 int scmi_one_xfer_init(const struct scmi_handle *h, u8 msg_id, u8 prot_id, 97 size_t tx_size, size_t rx_size, struct scmi_xfer **p); 98 int scmi_handle_put(const struct scmi_handle *handle); 99 struct scmi_handle *scmi_handle_get(struct device *dev); 100 void scmi_set_handle(struct scmi_device *scmi_dev); 101 int scmi_version_get(const struct scmi_handle *h, u8 protocol, u32 *version); 102 void scmi_setup_protocol_implemented(const struct scmi_handle *handle, 103 u8 *prot_imp); 104 105 int scmi_base_protocol_init(struct scmi_handle *h); 106