Altera Mentor Verification IP Altera Edition AMBA AXI3/4TM - Manual (Page 654)

Mentor VIP AE AXI3/4 User Guide, V10.2b 634
VHDL Tutorials
Verifying a Master DUT
September 2013
while(last = 0) loop
get_write_data_phase(write_trans, loop_i, last, index,
AXI_PATH_1, axi_tr_if_1(index));
get_write_addr_data(write_trans, loop_i, 0, byte_length, addr, data,
index, AXI_PATH_1, axi_tr_if_1(index));
do_byte_write(addr, data);
if byte_length > 1 then
for j in 1 to byte_length-1 loop
get_write_addr_data(write_trans, loop_i, j, byte_length,
addr, data, index, AXI_PATH_1, axi_tr_if_1(index));
do_byte_write(addr, data);
end loop;
end if;
loop_i := loop_i + 1;
end loop;
end if;
push_transaction_id(write_trans, AXI_QUEUE_ID_2, index, AXI_PATH_1,
axi_tr_if_1(index));
end loop;
wait;
end process;
The handle_response code extract demonstrates how to respond to a master write transaction
using a different path_id = AXI_PATH_2 than the path_id used for the address and data phases
of the same transaction. This gives the ability for the slave to execute a write transaction
response in a different order than the order received for a particular write_trans index number.
A write_trans variable is defined to hold this transaction index number before entering a loop to
pop a write transaction from AXI_QUEUE_ID_2 via the pop_transaction_id procedure call.
The delay for the BVALID signal is then set via the set_wr_resp_valid_delay procedure. The
response phase is then executed by the execute_write_response_phase procedure call (refer to
Example 11-27 ).
Example 11-27. handle_response
-- handle_response : write response phase through path 2
-- This method sends the write response phase
process
variable write_trans: integer;
begin
loop
pop_transaction_id(write_trans, AXI_QUEUE_ID_2, index, AXI_PATH_2,
axi_tr_if_2(index));
set_wr_resp_valid_delay(write_trans, AXI_PATH_2,
axi_tr_if_2(index));
execute_write_response_phase(write_trans, index, AXI_PATH_2,
axi_tr_if_2(index));
end loop;
wait;
end process;
The processing of read transactions works in a similar way as that described above for write
transactions. There are two processes
process_read and handle read .