1 /* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later */ 2 3 #ifndef _LIBMCTP_H 4 #define _LIBMCTP_H 5 6 #ifdef __cplusplus 7 extern "C" { 8 #endif 9 10 #include <stdarg.h> 11 #include <stdbool.h> 12 #include <stdint.h> 13 #include <stddef.h> 14 15 typedef uint8_t mctp_eid_t; 16 17 /* MCTP packet definitions */ 18 struct mctp_hdr { 19 uint8_t ver; 20 uint8_t dest; 21 uint8_t src; 22 uint8_t flags_seq_tag; 23 }; 24 25 /* Definitions for flags_seq_tag field */ 26 #define MCTP_HDR_FLAG_SOM (1<<7) 27 #define MCTP_HDR_FLAG_EOM (1<<6) 28 #define MCTP_HDR_FLAG_TO (1<<3) 29 #define MCTP_HDR_SEQ_SHIFT (4) 30 #define MCTP_HDR_SEQ_MASK (0x3) 31 #define MCTP_HDR_TAG_SHIFT (0) 32 #define MCTP_HDR_TAG_MASK (0x7) 33 34 /* Baseline maximum size of a MCTP packet */ 35 #define MCTP_BMTU_PAYLOAD 64 36 #define MCTP_BMTU (MCTP_BMTU_PAYLOAD + sizeof(struct mctp_hdr)) 37 38 /* packet buffers */ 39 40 struct mctp_pktbuf { 41 size_t start, end, size; 42 size_t mctp_hdr_off; 43 struct mctp_pktbuf *next; 44 unsigned char data[]; 45 }; 46 47 struct mctp_binding; 48 49 struct mctp_pktbuf *mctp_pktbuf_alloc(struct mctp_binding *hw, size_t len); 50 void mctp_pktbuf_free(struct mctp_pktbuf *pkt); 51 struct mctp_hdr *mctp_pktbuf_hdr(struct mctp_pktbuf *pkt); 52 void *mctp_pktbuf_data(struct mctp_pktbuf *pkt); 53 uint8_t mctp_pktbuf_size(struct mctp_pktbuf *pkt); 54 void *mctp_pktbuf_alloc_start(struct mctp_pktbuf *pkt, size_t size); 55 void *mctp_pktbuf_alloc_end(struct mctp_pktbuf *pkt, size_t size); 56 int mctp_pktbuf_push(struct mctp_pktbuf *pkt, void *data, size_t len); 57 58 /* MCTP core */ 59 struct mctp; 60 struct mctp_bus; 61 62 struct mctp *mctp_init(void); 63 64 /* Register a binding to the MCTP core, and creates a bus (populating 65 * binding->bus). 66 */ 67 int mctp_register_bus(struct mctp *mctp, 68 struct mctp_binding *binding, 69 mctp_eid_t eid); 70 71 typedef void (*mctp_rx_fn)(uint8_t src_eid, void *data, 72 void *msg, size_t len); 73 74 int mctp_set_rx_all(struct mctp *mctp, mctp_rx_fn fn, void *data); 75 76 int mctp_message_tx(struct mctp *mctp, mctp_eid_t eid, 77 void *msg, size_t msg_len); 78 79 /* hardware bindings */ 80 struct mctp_binding { 81 const char *name; 82 uint8_t version; 83 struct mctp_bus *bus; 84 struct mctp *mctp; 85 int pkt_size; 86 int pkt_pad; 87 int (*tx)(struct mctp_binding *binding, 88 struct mctp_pktbuf *pkt); 89 }; 90 91 void mctp_binding_set_tx_enabled(struct mctp_binding *binding, bool enable); 92 93 /* 94 * Receive a packet from binding to core. Takes ownership of pkt, free()-ing it 95 * after use. 96 */ 97 void mctp_bus_rx(struct mctp_binding *binding, struct mctp_pktbuf *pkt); 98 99 /* environment-specific allocation */ 100 void mctp_set_alloc_ops(void *(*alloc)(size_t), 101 void (*free)(void *), 102 void *(realloc)(void *, size_t)); 103 104 /* environment-specific logging */ 105 106 void mctp_set_log_stdio(int level); 107 void mctp_set_log_syslog(void); 108 void mctp_set_log_custom(void (*fn)(int, const char *, va_list)); 109 110 /* these should match the syslog-standard LOG_* definitions, for 111 * easier use with syslog */ 112 #define MCTP_LOG_ERR 3 113 #define MCTP_LOG_WARNING 4 114 #define MCTP_LOG_NOTICE 5 115 #define MCTP_LOG_INFO 6 116 #define MCTP_LOG_DEBUG 7 117 118 119 #ifdef __cplusplus 120 } 121 #endif 122 123 #endif /* _LIBMCTP_H */ 124