Altera Mentor Verification IP Altera Edition AMBA AXI3/4TM - Manual (Page 33)

SystemVerilog API Overview
Creating Transactions
Mentor VIP AE AXI3/4 User Guide, V10.2b 15
September 2013
Transaction Record
The transaction record contains two types of transaction fields, protocol and operational, that
either transfer information over the protocol signals or define how and when a transfer occurs.
Protocol fields contain transaction information that is transferred over protocol signals. For
example, the prot field is transferred over the AWPROT protocol signals during a write
transaction.
Operational fields define how and when the transaction is transferred. Their content is not
transferred over protocol signals. For example, the operation_mode field controls the
blocking/nonblocking operation of a transaction, but this information is not transferred over the
protocol signals.
AXI3 Transaction Definition
The transaction record exists as a SystemVerilog class definition in each BFM. Example 2-1
shows the definition of the axi_transaction class members that form the transaction record.
Example 2-1. AXI3 Transaction Definition
// Global Transaction Class
class axi_transaction;
// Protocol
bit [((`MAX_AXI_ADDRESS_WIDTH) - 1):0] addr;
axi_size_e size;
axi_burst_e burst;
axi_lock_e lock;
axi_cache_e cache;
axi_prot_e prot;
bit [((`MAX_AXI_ID_WIDTH) - 1):0] id;
bit [3:0] burst_length;
bit [((((`MAX_AXI_RDATA_WIDTH > `MAX_AXI_WDATA_WIDTH) ?
`MAX_AXI_RDATA_WIDTH : `MAX_AXI_WDATA_WIDTH)) - 1):0] data_words [];
bit [(((`MAX_AXI_WDATA_WIDTH / 8)) - 1):0] write_strobes [];
axi_response_e resp[];
bit [7:0] addr_user;
axi_rw_e read_or_write;
int address_valid_delay;
int data_valid_delay[];
int write_response_valid_delay;
int address_ready_delay;
int data_ready_delay[];
int write_response_ready_delay;
// Housekeeping
bit gen_write_strobes = 1'b1;
axi_operation_mode_e operation_mode = AXI_TRANSACTION_BLOCKING;
axi_delay_mode_e delay_mode = AXI_VALID2READY;
axi_write_data_mode_e write_data_mode = AXI_DATA_AFTER_ADDRESS;
bit data_beat_done[];
bit transaction_done;
...
endclass