Verilog AXI Components Readme
For more information and updates: http://alexforencich.com/wiki/en/verilog/axi/start
GitHub repository: https://github.com/alexforencich/verilog-axi
Introduction
Collection of AXI4 and AXI4 lite bus components. Most components are fully parametrizable in interface widths. Includes full MyHDL testbench with intelligent bus cosimulation endpoints.
Documentation
axi_adapter module
AXI width adapter module with parametrizable data and address interface widths. Supports INCR burst types and narrow bursts. Wrapper for axi_adapter_rd and axi_adapter_wr.
axi_adapter_rd module
AXI width adapter module with parametrizable data and address interface widths. Supports INCR burst types and narrow bursts.
axi_adapter_wr module
AXI width adapter module with parametrizable data and address interface widths. Supports INCR burst types and narrow bursts.
axi_cdma module
AXI to AXI DMA engine with parametrizable data and address interface widths. Generates full-width INCR bursts only, with parametrizable maximum burst length. Supports unaligned transfers, which can be disabled via parameter to save on resource consumption.
axi_cdma_desc_mux module
Descriptor multiplexer/demultiplexer for AXI CDMA module. Enables sharing the AXI CDMA module between multiple request sources, interleaving requests and distributing responses.
axi_crossbar module
AXI nonblocking crossbar interconnect with parametrizable data and address interface widths and master and slave interface counts. Supports all burst types. Fully nonblocking with completely separate read and write paths; ID based transaction ordering protection logic; and per-port address decode, admission control, and decode error handling. Wrapper for axi_crossbar_rd and axi_crossbar_wr.
axi_crossbar_addr module
Address decode and admission control module for AXI nonblocking crossbar interconnect.
axi_crossbar_rd module
AXI nonblocking crossbar interconnect with parametrizable data and address interface widths and master and slave interface counts. Read interface only. Supports all burst types. Fully nonblocking with completely separate read and write paths; ID based transaction ordering protection logic; and per-port address decode, admission control, and decode error handling.
axi_crossbar_wr module
AXI nonblocking crossbar interconnect with parametrizable data and address interface widths and master and slave interface counts. Write interface only. Supports all burst types. Fully nonblocking with completely separate read and write paths; ID based transaction ordering protection logic; and per-port address decode, admission control, and decode error handling.
axi_dma module
AXI to AXI stream DMA engine with parametrizable data and address interface widths. Generates full-width INCR bursts only, with parametrizable maximum burst length. Supportts unaligned transfers, which can be disabled via parameter to save on resource consumption. Wrapper for axi_dma_rd and axi_dma_wr.
axi_dma_desc_mux module
Descriptor multiplexer/demultiplexer for AXI DMA module. Enables sharing the AXI DMA module between multiple request sources, interleaving requests and distributing responses.
axi_dma_rd module
AXI to AXI stream DMA engine with parametrizable data and address interface widths. Generates full-width INCR bursts only, with parametrizable maximum burst length. Supportts unaligned transfers, which can be disabled via parameter to save on resource consumption.
axi_dma_wr module
AXI stream to AXI DMA engine with parametrizable data and address interface widths. Generates full-width INCR bursts only, with parametrizable maximum burst length. Supportts unaligned transfers, which can be disabled via parameter to save on resource consumption.
axi_fifo module
AXI FIFO with parametrizable data and address interface widths. Supports all burst types. Optionally can delay the address channel until either the write data is completely shifted into the FIFO or the read data FIFO has enough capacity to fit the whole burst. Wrapper for axi_fifo_rd and axi_fifo_wr.
axi_fifo_rd module
AXI FIFO with parametrizable data and address interface widths. AR and R channels only. Supports all burst types. Optionally can delay the address channel until either the read data FIFO is empty or has enough capacity to fit the whole burst.
axi_fifo_wr module
AXI FIFO with parametrizable data and address interface widths. WR, W, and B channels only. Supports all burst types. Optionally can delay the address channel until the write data is shifted completely into the write data FIFO, or the current burst completely fills the write data FIFO.
axi_interconnect module
AXI shared interconnect with parametrizable data and address interface widths and master and slave interface counts. Supports all burst types. Small in area, but does not support concurrent operations.
axi_ram module
AXI RAM with parametrizable data and address interface widths. Supports FIXED and INCR burst types as well as narrow bursts.
axi_register module
AXI register with parametrizable data and address interface widths. Supports all burst types. Inserts simple buffers or skid buffers into all channels. Channel register types can be individually changed or bypassed. Wrapper for axi_register_rd and axi_register_wr.
axi_register_rd module
AXI register with parametrizable data and address interface widths. AR and R channels only. Supports all burst types. Inserts simple buffers or skid buffers into all channels. Channel register types can be individually changed or bypassed.
axi_register_wr module
AXI register with parametrizable data and address interface widths. WR, W, and B channels only. Supports all burst types. Inserts simple buffers or skid buffers into all channels. Channel register types can be individually changed or bypassed.
axil_adapter module
AXI lite width adapter module with parametrizable data and address interface widths. Wrapper for axi_adapter_rd and axi_adapter_wr.
axil_adapter_rd module
AXI lite width adapter module with parametrizable data and address interface widths.
axil_adapter_wr module
AXI lite width adapter module with parametrizable data and address interface widths.
axil_interconnect module
AXI lite shared interconnect with parametrizable data and address interface widths and master and slave interface counts. Small in area, but does not support concurrent operations.
axil_ram module
AXI lite RAM with parametrizable data and address interface widths.
axil_register module
AXI lite register with parametrizable data and address interface widths. Inserts skid buffers into all channels. Channel registers can be individually bypassed. Wrapper for axil_register_rd and axil_register_wr.
axil_register_rd module
AXI lite register with parametrizable data and address interface widths. AR and R channels only. Inserts simple buffers into all channels. Channel registers can be individually bypassed.
axil_register_wr module
AXI lite register with parametrizable data and address interface widths. WR, W, and B channels only. Inserts simple buffers into all channels. Channel registers can be individually bypassed.
Common signals
awid : Write address ID awaddr : Write address awlen : Write burst length awsize : Write burst size awburst : Write burst type awlock : Write locking awcache : Write cache handling awprot : Write protection level awqos : Write QoS setting awregion : Write region awuser : Write user sideband signal awvalid : Write address valid awready : Write address ready (from slave) wdata : Write data wstrb : Write data strobe (byte select) wlast : Write data last transfer in burst wuser : Write data user sideband signal wvalid : Write data valid wready : Write data ready (from slave) bid : Write response ID bresp : Write response buser : Write response user sideband signal bvalid : Write response valid bready : Write response ready (from master) arid : Read address ID araddr : Read address arlen : Read burst length arsize : Read burst size arburst : Read burst type arlock : Read locking arcache : Read cache handling arprot : Read protection level arqos : Read QoS setting arregion : Read region aruser : Read user sideband signal arvalid : Read address valid arready : Read address ready (from slave) rid : Read data ID rdata : Read data rresp : Read response rlast : Read data last transfer in burst ruser : Read data user sideband signal rvalid : Read response valid rready : Read response ready (from master)
Common parameters
ADDR_WIDTH : width of awaddr and araddr signals DATA_WIDTH : width of wdata and rdata signals STRB_WIDTH : width of wstrb signal ID_WIDTH : width of *id signals AWUSER_ENABLE : enable awuser signal AWUSER_WIDTH : width of awuser signal WUSER_ENABLE : enable wuser signal WUSER_WIDTH : width of wuser signal BUSER_ENABLE : enable buser signal BUSER_WIDTH : width of buser signal ARUSER_ENABLE : enable aruser signal ARUSER_WIDTH : width of aruser signal RUSER_ENABLE : enable ruser signal RUSER_WIDTH : width of ruser signal
Source Files
rtl/arbiter.v : Parametrizable arbiter rtl/axi_adapter.v : AXI lite width converter rtl/axi_adapter_rd.v : AXI lite width converter (read) rtl/axi_adapter_wr.v : AXI lite width converter (write) rtl/axi_cdma.v : AXI central DMA engine rtl/axi_cdma_desc_mux.v : AXI CDMA descriptor mux rtl/axi_crossbar.v : AXI nonblocking crossbar interconnect rtl/axi_crossbar_addr.v : AXI crossbar address module rtl/axi_crossbar_rd.v : AXI crossbar read module rtl/axi_crossbar_wr.v : AXI crossbar write module rtl/axi_dma.v : AXI DMA engine rtl/axi_dma_desc_mux.v : AXI DMA descriptor mux rtl/axi_dma_rd.v : AXI DMA engine (read) rtl/axi_dma_wr.v : AXI DMA engine (write) rtl/axi_fifo.v : AXI FIFO rtl/axi_fifo_rd.v : AXI FIFO (read) rtl/axi_fifo_wr.v : AXI FIFO (write) rtl/axi_interconnect.v : AXI shared interconnect rtl/axi_ram.v : AXI RAM rtl/axi_register.v : AXI register rtl/axi_register_rd.v : AXI register (read) rtl/axi_register_wr.v : AXI register (write) rtl/axil_adapter.v : AXI lite width converter rtl/axil_adapter_rd.v : AXI lite width converter (read) rtl/axil_adapter_wr.v : AXI lite width converter (write) rtl/axil_interconnect.v : AXI lite shared interconnect rtl/axil_ram.v : AXI lite RAM rtl/axil_register.v : AXI lite register rtl/axil_register_rd.v : AXI lite register (read) rtl/axil_register_wr.v : AXI lite register (write) rtl/priority_encoder.v : Parametrizable priority encoder
AXI4-Lite Interface Example
Write
___ ___ ___ ___ ___ clk ___/ \___/ \___/ \___/ \___/ \___ _______ awid XXXX_ID____XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ awaddr XXXX_ADDR__XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ awlen XXXX_00____XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ awsize XXXX_0_____XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ awburst XXXX_0_____XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ awprot XXXX_PROT__XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ awvalid ___/ \_______________________________ ___________ _______________________ awready \_______/ _______________ wdata XXXX_DATA__________XXXXXXXXXXXXXXXXXXXXXXXX _______________ wstrb XXXX_STRB__________XXXXXXXXXXXXXXXXXXXXXXXX _______________ wvalid ___/ \_______________________ _______ wready ___________/ \_______________________ _______ bid XXXXXXXXXXXXXXXXXXXXXXXXXXXX_ID____XXXXXXXX _______ bresp XXXXXXXXXXXXXXXXXXXXXXXXXXXX_RESP__XXXXXXXX _______ bvalid ___________________________/ \_______ ___________________________________________ bready
Read
___ ___ ___ ___ ___ clk ___/ \___/ \___/ \___/ \___/ \___ _______ arid XXXX_ID____XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ araddr XXXX_ADDR__XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ arlen XXXX_00____XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ arsize XXXX_0_____XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ arburst XXXX_0_____XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ arprot XXXX_PROT__XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX _______ arvalid ___/ \_______________________________ ___________________________________________ arready _______ rid XXXXXXXXXXXXXXXXXXXXXXXXXXXX_ID____XXXXXXXX _______ rdata XXXXXXXXXXXXXXXXXXXXXXXXXXXX_DATA__XXXXXXXX _______ rresp XXXXXXXXXXXXXXXXXXXXXXXXXXXX_RESP__XXXXXXXX _______ rvalid ___________________________/ \_______ ___________________________________________ rready
Testing
Running the included testbenches requires MyHDL and Icarus Verilog. Make sure that myhdl.vpi is installed properly for cosimulation to work correctly. The testbenches can be run with a Python test runner like nose or py.test, or the individual test scripts can be run with python directly.
Testbench Files
tb/axi.py : MyHDL AXI4 master and memory BFM tb/axil.py : MyHDL AXI4 lite master and memory BFM