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 #include <asm/unaligned.h> 19 20 #define PROTOCOL_REV_MINOR_MASK GENMASK(15, 0) 21 #define PROTOCOL_REV_MAJOR_MASK GENMASK(31, 16) 22 #define PROTOCOL_REV_MAJOR(x) (u16)(FIELD_GET(PROTOCOL_REV_MAJOR_MASK, (x))) 23 #define PROTOCOL_REV_MINOR(x) (u16)(FIELD_GET(PROTOCOL_REV_MINOR_MASK, (x))) 24 #define MAX_PROTOCOLS_IMP 16 25 #define MAX_OPPS 16 26 27 enum scmi_common_cmd { 28 PROTOCOL_VERSION = 0x0, 29 PROTOCOL_ATTRIBUTES = 0x1, 30 PROTOCOL_MESSAGE_ATTRIBUTES = 0x2, 31 }; 32 33 /** 34 * struct scmi_msg_resp_prot_version - Response for a message 35 * 36 * @major_version: Major version of the ABI that firmware supports 37 * @minor_version: Minor version of the ABI that firmware supports 38 * 39 * In general, ABI version changes follow the rule that minor version increments 40 * are backward compatible. Major revision changes in ABI may not be 41 * backward compatible. 42 * 43 * Response to a generic message with message type SCMI_MSG_VERSION 44 */ 45 struct scmi_msg_resp_prot_version { 46 __le16 minor_version; 47 __le16 major_version; 48 }; 49 50 /** 51 * struct scmi_msg_hdr - Message(Tx/Rx) header 52 * 53 * @id: The identifier of the message being sent 54 * @protocol_id: The identifier of the protocol used to send @id message 55 * @seq: The token to identify the message. When a message returns, the 56 * platform returns the whole message header unmodified including the 57 * token 58 * @status: Status of the transfer once it's complete 59 * @poll_completion: Indicate if the transfer needs to be polled for 60 * completion or interrupt mode is used 61 */ 62 struct scmi_msg_hdr { 63 u8 id; 64 u8 protocol_id; 65 u16 seq; 66 u32 status; 67 bool poll_completion; 68 }; 69 70 /** 71 * struct scmi_msg - Message(Tx/Rx) structure 72 * 73 * @buf: Buffer pointer 74 * @len: Length of data in the Buffer 75 */ 76 struct scmi_msg { 77 void *buf; 78 size_t len; 79 }; 80 81 /** 82 * struct scmi_xfer - Structure representing a message flow 83 * 84 * @hdr: Transmit message header 85 * @tx: Transmit message 86 * @rx: Receive message, the buffer should be pre-allocated to store 87 * message. If request-ACK protocol is used, we can reuse the same 88 * buffer for the rx path as we use for the tx path. 89 * @done: command message transmit completion event 90 * @async: pointer to delayed response message received event completion 91 */ 92 struct scmi_xfer { 93 struct scmi_msg_hdr hdr; 94 struct scmi_msg tx; 95 struct scmi_msg rx; 96 struct completion done; 97 struct completion *async_done; 98 }; 99 100 void scmi_xfer_put(const struct scmi_handle *h, struct scmi_xfer *xfer); 101 int scmi_do_xfer(const struct scmi_handle *h, struct scmi_xfer *xfer); 102 int scmi_do_xfer_with_response(const struct scmi_handle *h, 103 struct scmi_xfer *xfer); 104 int scmi_xfer_get_init(const struct scmi_handle *h, u8 msg_id, u8 prot_id, 105 size_t tx_size, size_t rx_size, struct scmi_xfer **p); 106 int scmi_handle_put(const struct scmi_handle *handle); 107 struct scmi_handle *scmi_handle_get(struct device *dev); 108 void scmi_set_handle(struct scmi_device *scmi_dev); 109 int scmi_version_get(const struct scmi_handle *h, u8 protocol, u32 *version); 110 void scmi_setup_protocol_implemented(const struct scmi_handle *handle, 111 u8 *prot_imp); 112 113 int scmi_base_protocol_init(struct scmi_handle *h); 114