1 /* SPDX-License-Identifier: Apache-2.0 */ 2 3 #ifndef _LIBMCTP_H 4 #define _LIBMCTP_H 5 6 #include <stdint.h> 7 8 typedef uint8_t mctp_eid_t; 9 10 /* MCTP packet definitions */ 11 struct mctp_hdr { 12 uint8_t ver; 13 uint8_t dest; 14 uint8_t src; 15 uint8_t flags_seq_tag; 16 }; 17 18 /* Definitions for flags_seq_tag field */ 19 #define MCTP_HDR_FLAG_SOM (1<<7) 20 #define MCTP_HDR_FLAG_EOM (1<<6) 21 #define MCTP_HDR_FLAG_TO (1<<3) 22 #define MCTP_HDR_SEQ_SHIFT (5) 23 #define MCTP_HDR_SEQ_MASK (0x3) 24 #define MCTP_HDR_TAG_SHIFT (0) 25 #define MCTP_HDR_TAG_MASK (0x7) 26 27 /* Maximum size of *payload* data in a MCTP packet 28 * @todo: dynamic sixing based on channel implementation. 29 */ 30 #define MCTP_MTU 64 31 32 /* packet buffers */ 33 34 /* Allow a little space before the MCTP header in the packet, for bindings that 35 * may add their own header 36 */ 37 #define MCTP_PKTBUF_BINDING_PAD 2 38 39 #define MCTP_PKTBUF_SIZE (MCTP_PKTBUF_BINDING_PAD + \ 40 (sizeof(struct mctp_hdr) + MCTP_MTU) 41 42 struct mctp_pktbuf { 43 unsigned char data[MCTP_PKTBUF_SIZE]; 44 uint8_t start, end; 45 uint8_t mctp_hdr_off; 46 }; 47 48 struct mctp_pktbuf *mctp_pktbuf_alloc(uint8_t len); 49 void mctp_pktbuf_free(struct mctp_pktbuf *pkt); 50 struct mctp_hdr *mctp_pktbuf_hdr(struct mctp_pktbuf *pkt); 51 void *mctp_pktbuf_data(struct mctp_pktbuf *pkt); 52 uint8_t mctp_pktbuf_size(struct mctp_pktbuf *pkt); 53 void *mctp_pktbuf_alloc_start(struct mctp_pktbuf *pkt, uint8_t size); 54 void *mctp_pktbuf_alloc_end(struct mctp_pktbuf *pkt, uint8_t size); 55 int mctp_pktbuf_push(struct mctp_pktbuf *pkt, void *data, uint8_t len); 56 57 /* MCTP core */ 58 struct mctp; 59 struct mctp_binding; 60 61 struct mctp *mctp_init(void); 62 63 unsigned long mctp_register_bus(struct mctp *mctp, 64 struct mctp_binding *binding, 65 mctp_eid_t eid); 66 67 typedef void (*mctp_rx_fn)(uint8_t src_eid, void *data, 68 void *msg, size_t len); 69 70 int mctp_set_rx_all(struct mctp *mctp, mctp_rx_fn fn, void *data); 71 72 int mctp_message_tx(struct mctp *mctp, mctp_eid_t eid, 73 void *msg, size_t msg_len); 74 75 /* hardware bindings */ 76 struct mctp_binding { 77 const char *name; 78 uint8_t version; 79 int (*tx)(struct mctp_binding *binding, 80 struct mctp_pktbuf *pkt); 81 }; 82 83 void mctp_bus_rx(struct mctp *mctp, unsigned long bus_id, 84 struct mctp_pktbuf *pkt); 85 86 /* environment-specific allocation */ 87 void mctp_set_alloc_ops(void *(*alloc)(size_t), 88 void (*free)(void *), 89 void *(realloc)(void *, size_t)); 90 91 92 #endif /* _LIBMCTP_H */ 93