作者：张海军，来源： 傅里叶的猫微信公众号
AXI接口虽然经常使用，很多同学可能并不清楚Vivado里面也集成了AXI的Verification IP，可以当做AXI的master、pass through和slave，本次内容我们看下AXI VIP当作master时如何使用。
新建Vivado工程，并新建block design，命名为：axi_demo
新建axi vip，参数设置如下，第一个参数设置为Master，其他都保持默认，当然如果可以根据自己的实际需求作改动，比如id位宽，数据位宽等等。
再添加AXI BRAM Controller和Block Memory Generator：
地址分配如下：0xc000_0000
生成ip的各种文件：
新建仿真的tb_top文件，需要注意，文件类型是system verilog。
仿真代码放到文章末尾，代码中中导入的axi_demo_axi_vip_0_0_pkg，就是下面axi vip的component_name再加上后缀_pkg，后面的mst_agent也是component_name加上后缀 _mst_t
import axi_demo_axi_vip_0_0_pkg::*;
axi_demo_axi_vip_0_0_mst_t mst_agent;
运行仿真：
将axi vip的M-AXI添加到波形窗口中：
可以看到，我们一开始向地址0xc0001000写入0x12345678，又发起一次读操作，可以将该数据读出。
有同学可能习惯用vcs来仿真，下篇文章我们再用vcs+verdi来仿真vivado的axi vip。
`timescale 1ns / 1ps
import axi_vip_pkg::*;
import axi_demo_axi_vip_0_0_pkg::*;
module tb_top();
bit clk;
bit aresetn;
//used in API and parital randomization for transaction generation and data read back from driver
axi_transaction wr_transaction; // Write transaction
axi_transaction rd_transaction; // Read transaction
xil_axi_uint mtestWID; // Write ID
xil_axi_ulong mtestWADDR; // Write ADDR
xil_axi_len_t mtestWBurstLength; // Write Burst Length
xil_axi_size_t mtestWDataSize; // Write SIZE
xil_axi_burst_t mtestWBurstType; // Write Burst Type
xil_axi_uint mtestRID; // Read ID
xil_axi_ulong mtestRADDR; // Read ADDR
xil_axi_len_t mtestRBurstLength; // Read Burst Length
xil_axi_size_t mtestRDataSize; // Read SIZE
xil_axi_burst_t mtestRBurstType; // Read Burst Type
xil_axi_lock_t mtestLOCK; // LOCK value for WRITE/READ_BURST transaction
xil_axi_cache_t mtestCacheType = 3; // Cache Type value for WRITE/READ_BURST transaction
xil_axi_prot_t mtestProtectionType = 3'b000; // Protection Type value for WRITE/READ_BURST transaction
xil_axi_region_t mtestRegion = 4'b000; // Region value for WRITE/READ_BURST transaction
xil_axi_qos_t mtestQOS = 4'b000; // QOS value for WRITE/READ_BURST transaction
xil_axi_data_beat dbeat; // Data beat value for WRITE/READ_BURST transaction
xil_axi_user_beat usrbeat; // User beat value for WRITE/READ_BURST transaction
xil_axi_data_beat [255:0] mtestWUSER; // Wuser value for WRITE/READ_BURST transaction
xil_axi_data_beat mtestAWUSER = 'h0; // Awuser value for WRITE/READ_BURST transaction
xil_axi_data_beat mtestARUSER = 0; // Aruser value for WRITE/READ_BURST transaction
xil_axi_data_beat [255:0] mtestRUSER; // Ruser value for WRITE/READ_BURST transaction
xil_axi_uint mtestBUSER = 0; // Buser value for WRITE/READ_BURST transaction
xil_axi_resp_t mtestBresp; // Bresp value for WRITE/READ_BURST transaction
xil_axi_resp_t[255:0] mtestRresp; // Rresp value for WRITE/READ_BURST transaction
bit [63:0] mtestWData; // Write Data
bit[8*4096-1:0] Wdatablock; // Write data block
xil_axi_data_beat Wdatabeat[]; // Write data beats
bit [63:0] mtestRData; // Read Data
bit[8*4096-1:0] Rdatablock; // Read data block
xil_axi_data_beat Rdatabeat[]; // Read data beats
initial begin
aresetn = 1'b0;
clk = 1'b0;
#100ns;
aresetn = 1'b1;
end
always #10 clk <= ~clk;
axi_demo u_dut(
.aclk_0 (clk ),
.aresetn_0 (aresetn )
);
axi_demo_axi_vip_0_0_mst_t mst_agent;
initial begin
mst_agent = new("master vip agent",u_dut.axi_vip_0.inst.IF);
mst_agent.start_master(); // mst_agent start to run
mtestWID = $urandom_range(0,(1<<(0)-1));
mtestWADDR = 'hc000_1000;//$urandom_range(0,(1<<(32)-1));
mtestWBurstLength = 0;
mtestWDataSize = xil_axi_size_t'(xil_clog2((32)/8));
mtestWBurstType = XIL_AXI_BURST_TYPE_INCR;
mtestWData = 'h12345678;//$urandom();
$display("mtestWDataSize = %d", mtestWDataSize);
//single write transaction filled in user inputs through API
single_write_transaction_api("single write with api",
.id(mtestWID),
.addr(mtestWADDR),
.len(mtestWBurstLength),
.size(mtestWDataSize),
.burst(mtestWBurstType),
.wuser(mtestWUSER),
.awuser(mtestAWUSER),
.data(mtestWData)
);
mtestRID = $urandom_range(0,(1<<(0)-1));
mtestRADDR = mtestWADDR;
mtestRBurstLength = 0;
mtestRDataSize = xil_axi_size_t'(xil_clog2((32)/8));
mtestRBurstType = XIL_AXI_BURST_TYPE_INCR;
$display("mtestRDataSize = %d", mtestRDataSize);
//single read transaction filled in user inputs through API
single_read_transaction_api("single read with api",
.id(mtestRID),
.addr(mtestRADDR),
.len(mtestRBurstLength),
.size(mtestRDataSize),
.burst(mtestRBurstType)
);
end
task automatic single_write_transaction_api (
input string name ="single_write",
input xil_axi_uint id =0,
input xil_axi_ulong addr =0,
input xil_axi_len_t len =0,
input xil_axi_size_t size =xil_axi_size_t'(xil_clog2((32)/8)),
input xil_axi_burst_t burst =XIL_AXI_BURST_TYPE_INCR,
input xil_axi_lock_t lock = XIL_AXI_ALOCK_NOLOCK,
input xil_axi_cache_t cache =3,
input xil_axi_prot_t prot =0,
input xil_axi_region_t region =0,
input xil_axi_qos_t qos =0,
input xil_axi_data_beat [255:0] wuser =0,
input xil_axi_data_beat awuser =0,
input bit [63:0] data =0
);
axi_transaction wr_trans;
$display("single_write_transaction_api size = %d", size);
wr_trans = mst_agent.wr_driver.create_transaction(name);
wr_trans.set_write_cmd(addr,burst,id,len,size);
wr_trans.set_prot(prot);
wr_trans.set_lock(lock);
wr_trans.set_cache(cache);
wr_trans.set_region(region);
wr_trans.set_qos(qos);
wr_trans.set_data_block(data);
mst_agent.wr_driver.send(wr_trans);
endtask : single_write_transaction_api
task automatic single_read_transaction_api (
input string name ="single_read",
input xil_axi_uint id =0,
input xil_axi_ulong addr =0,
input xil_axi_len_t len =0,
input xil_axi_size_t size =xil_axi_size_t'(xil_clog2((32)/8)),
input xil_axi_burst_t burst =XIL_AXI_BURST_TYPE_INCR,
input xil_axi_lock_t lock =XIL_AXI_ALOCK_NOLOCK ,
input xil_axi_cache_t cache =3,
input xil_axi_prot_t prot =0,
input xil_axi_region_t region =0,
input xil_axi_qos_t qos =0,
input xil_axi_data_beat aruser =0
);
axi_transaction rd_trans;
$display("single_read_transaction_api size = %d", size);
rd_trans = mst_agent.rd_driver.create_transaction(name);
rd_trans.set_read_cmd(addr,burst,id,len,size);
rd_trans.set_prot(prot);
rd_trans.set_lock(lock);
rd_trans.set_cache(cache);
rd_trans.set_region(region);
rd_trans.set_qos(qos);
mst_agent.rd_driver.send(rd_trans);
endtask : single_read_transaction_api
endmodule
