Zynq/Pynq PWM-Generator 从PL设计到PS的SDK开发
本文将PWM发生器的PL设计封装成“伪IP核”的RTL，并提供了相应的SDK供大家使用PS来操作PWM。
具体的开发流程在此文中不做过多阐述，这里推荐一篇博客，把全流程都涵盖了。https://blog.csdn.net/qq_42263796/article/details/101828046
HDL
共3个文件。本来是打算用AXI4自定义一个IP核的，但经过我自己的努力尝试，都未能解决AXI总线的接口报错问题，遂将其作为封装好的RTL使用。
pwm_gen.v
`timescale 1ns / 1ps
module pwm_gen #
(
parameter WIDTH=32
)
(
input wire clk, rst,
input wire [WIDTH-1:0] load, compare, control,
output wire pwm_out
);
reg [WIDTH-1:0] count;
reg pwm_out_r;
// Make sure output is low if PWM is disabled
assign pwm_out = control[0] & pwm_out_r;
initial begin
pwm_out_r = 1'b0;
count = {WIDTH{1'b0}};
end
// The counter
always @(posedge clk) begin
if(!rst)
count = {WIDTH{1'b0}};
else if (count < load && control[0])
count = count + 1;
else
count = 0;
end
always @(negedge clk) begin
if(!rst)
pwm_out_r = 1'b0;
else begin
case(count)
0 : pwm_out_r = 1'b1;
compare : pwm_out_r = 1'b0;
default : pwm_out_r = pwm_out_r;
endcase
end
end
endmodule
pwm_generator_v1_0.v
`timescale 1 ns / 1 ps
module pwm_generator_v1_0 #
(
// Users to add parameters here
// User parameters ends
// Do not modify the parameters beyond this line
// Parameters of Axi Slave Bus Interface S00_AXI
parameter integer C_S00_AXI_DATA_WIDTH = 32,
parameter integer C_S00_AXI_ADDR_WIDTH = 4
)
(
// Users to add ports here
output wire pwm_out,
// User ports ends
// Do not modify the ports beyond this line
// Ports of Axi Slave Bus Interface S00_AXI
input wire s00_axi_aclk,
input wire s00_axi_aresetn,
input wire [C_S00_AXI_ADDR_WIDTH-1 : 0] s00_axi_awaddr,
input wire [2 : 0] s00_axi_awprot,
input wire s00_axi_awvalid,
output wire s00_axi_awready,
input wire [C_S00_AXI_DATA_WIDTH-1 : 0] s00_axi_wdata,
input wire [(C_S00_AXI_DATA_WIDTH/8)-1 : 0] s00_axi_wstrb,
input wire s00_axi_wvalid,
output wire s00_axi_wready,
output wire [1 : 0] s00_axi_bresp,
output wire s00_axi_bvalid,
input wire s00_axi_bready,
input wire [C_S00_AXI_ADDR_WIDTH-1 : 0] s00_axi_araddr,
input wire [2 : 0] s00_axi_arprot,
input wire s00_axi_arvalid,
output wire s00_axi_arready,
output wire [C_S00_AXI_DATA_WIDTH-1 : 0] s00_axi_rdata,
output wire [1 : 0] s00_axi_rresp,
output wire s00_axi_rvalid,
input wire s00_axi_rready
);
// Instantiation of Axi Bus Interface S00_AXI
pwm_generator_v1_0_S00_AXI # (
.C_S_AXI_DATA_WIDTH(C_S00_AXI_DATA_WIDTH),
.C_S_AXI_ADDR_WIDTH(C_S00_AXI_ADDR_WIDTH)
) pwm_generator_v1_0_S00_AXI_inst (
.pwm_out(pwm_out),
.S_AXI_ACLK(s00_axi_aclk),
.S_AXI_ARESETN(s00_axi_aresetn),
.S_AXI_AWADDR(s00_axi_awaddr),
.S_AXI_AWPROT(s00_axi_awprot),
.S_AXI_AWVALID(s00_axi_awvalid),
.S_AXI_AWREADY(s00_axi_awready),
.S_AXI_WDATA(s00_axi_wdata),
.S_AXI_WSTRB(s00_axi_wstrb),
.S_AXI_WVALID(s00_axi_wvalid),
.S_AXI_WREADY(s00_axi_wready),
.S_AXI_BRESP(s00_axi_bresp),
.S_AXI_BVALID(s00_axi_bvalid),
.S_AXI_BREADY(s00_axi_bready),
.S_AXI_ARADDR(s00_axi_araddr),
.S_AXI_ARPROT(s00_axi_arprot),
.S_AXI_ARVALID(s00_axi_arvalid),
.S_AXI_ARREADY(s00_axi_arready),
.S_AXI_RDATA(s00_axi_rdata),
.S_AXI_RRESP(s00_axi_rresp),
.S_AXI_RVALID(s00_axi_rvalid),
.S_AXI_RREADY(s00_axi_rready)
);
// Add user logic here
// User logic ends
endmodule
pwm_generator_v1_0_S00_AXI.v
`timescale 1 ns / 1 ps
module pwm_generator_v1_0_S00_AXI #
(
// Users to add parameters here
// User parameters ends
// Do not modify the parameters beyond this line
// Width of S_AXI data bus
parameter integer C_S_AXI_DATA_WIDTH = 32,
// Width of S_AXI address bus
parameter integer C_S_AXI_ADDR_WIDTH = 4
)
(
// Users to add ports here
output wire pwm_out,
// User ports ends
// Do not modify the ports beyond this line
// Global Clock Signal
input wire S_AXI_ACLK,
// Global Reset Signal. This Signal is Active LOW
input wire S_AXI_ARESETN,
// Write address (issued by master, acceped by Slave)
input wire [C_S_AXI_ADDR_WIDTH-1 : 0] S_AXI_AWADDR,
// Write channel Protection type. This signal indicates the
// privilege and security level of the transaction, and whether
// the transaction is a data access or an instruction access.
input wire [2 : 0] S_AXI_AWPROT,
// Write address valid. This signal indicates that the master signaling
// valid write address and control information.
input wire S_AXI_AWVALID,
// Write address ready. This signal indicates that the slave is ready
// to accept an address and associated control signals.
output wire S_AXI_AWREADY,
// Write data (issued by master, acceped by Slave)
input wire [C_S_AXI_DATA_WIDTH-1 : 0] S_AXI_WDATA,
// Write strobes. This signal indicates which byte lanes hold
// valid data. There is one write strobe bit for each eight
// bits of the write data bus.
input wire [(C_S_AXI_DATA_WIDTH/8)-1 : 0] S_AXI_WSTRB,
// Write valid. This signal indicates that valid write
// data and strobes are available.
input wire S_AXI_WVALID,
// Write ready. This signal indicates that the slave
// can accept the write data.
output wire S_AXI_WREADY,
// Write response. This signal indicates the status
// of the write transaction.
output wire [1 : 0] S_AXI_BRESP,
// Write response valid. This signal indicates that the channel
// is signaling a valid write response.
output wire S_AXI_BVALID,
// Response ready. This signal indicates that the master
// can accept a write response.
input wire S_AXI_BREADY,
// Read address (issued by master, acceped by Slave)
input wire [C_S_AXI_ADDR_WIDTH-1 : 0] S_AXI_ARADDR,
// Protection type. This signal indicates the privilege
// and security level of the transaction, and whether the
// transaction is a data access or an instruction access.
input wire [2 : 0] S_AXI_ARPROT,
// Read address valid. This signal indicates that the channel
// is signaling valid read address and control information.
input wire S_AXI_ARVALID,
// Read address ready. This signal indicates that the slave is
// ready to accept an address and associated control signals.
output wire S_AXI_ARREADY,
// Read data (issued by slave)
output wire [C_S_AXI_DATA_WIDTH-1 : 0] S_AXI_RDATA,
// Read response. This signal indicates the status of the
// read transfer.
output wire [1 : 0] S_AXI_RRESP,
// Read valid. This signal indicates that the channel is
// signaling the required read data.
output wire S_AXI_RVALID,
// Read ready. This signal indicates that the master can
// accept the read data and response information.
input wire S_AXI_RREADY
);
// AXI4LITE signals
reg [C_S_AXI_ADDR_WIDTH-1 : 0] axi_awaddr;
reg axi_awready;
reg axi_wready;
reg [1 : 0] axi_bresp;
reg axi_bvalid;
reg [C_S_AXI_ADDR_WIDTH-1 : 0] axi_araddr;
reg axi_arready;
reg [C_S_AXI_DATA_WIDTH-1 : 0] axi_rdata;
reg [1 : 0] axi_rresp;
reg axi_rvalid;
// Example-specific design signals
// local parameter for addressing 32 bit / 64 bit C_S_AXI_DATA_WIDTH
// ADDR_LSB is used for addressing 32/64 bit registers/memories
// ADDR_LSB = 2 for 32 bits (n downto 2)
// ADDR_LSB = 3 for 64 bits (n downto 3)
localparam integer ADDR_LSB = (C_S_AXI_DATA_WIDTH/32) + 1;
localparam integer OPT_MEM_ADDR_BITS = 1;
//----------------------------------------------
//-- Signals for user logic register space example
//------------------------------------------------
//-- Number of Slave Registers 4
reg [C_S_AXI_DATA_WIDTH-1:0] load_reg;
reg [C_S_AXI_DATA_WIDTH-1:0] compare_reg;
reg [C_S_AXI_DATA_WIDTH-1:0] control_reg;
reg [C_S_AXI_DATA_WIDTH-1:0] unused_reg;
wire slv_reg_rden;
wire slv_reg_wren;
reg [C_S_AXI_DATA_WIDTH-1:0] reg_data_out;
integer byte_index;
reg aw_en;
// I/O Connections assignments
assign S_AXI_AWREADY = axi_awready;
assign S_AXI_WREADY = axi_wready;
assign S_AXI_BRESP = axi_bresp;
assign S_AXI_BVALID = axi_bvalid;
assign S_AXI_ARREADY = axi_arready;
assign S_AXI_RDATA = axi_rdata;
assign S_AXI_RRESP = axi_rresp;
assign S_AXI_RVALID = axi_rvalid;
// Implement axi_awready generation
// axi_awready is asserted for one S_AXI_ACLK clock cycle when both
// S_AXI_AWVALID and S_AXI_WVALID are asserted. axi_awready is
// de-asserted when reset is low.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_awready <= 1'b0;
aw_en <= 1'b1;
end
else
begin
if (~axi_awready && S_AXI_AWVALID && S_AXI_WVALID && aw_en)
begin
// slave is ready to accept write address when
// there is a valid write address and write data
// on the write address and data bus. This design
// expects no outstanding transactions.
axi_awready <= 1'b1;
aw_en <= 1'b0;
end
else if (S_AXI_BREADY && axi_bvalid)
begin
aw_en <= 1'b1;
axi_awready <= 1'b0;
end
else
begin
axi_awready <= 1'b0;
end
end
end
// Implement axi_awaddr latching
// This process is used to latch the address when both
// S_AXI_AWVALID and S_AXI_WVALID are valid.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_awaddr <= 0;
end
else
begin
if (~axi_awready && S_AXI_AWVALID && S_AXI_WVALID && aw_en)
begin
// Write Address latching
axi_awaddr <= S_AXI_AWADDR;
end
end
end
// Implement axi_wready generation
// axi_wready is asserted for one S_AXI_ACLK clock cycle when both
// S_AXI_AWVALID and S_AXI_WVALID are asserted. axi_wready is
// de-asserted when reset is low.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_wready <= 1'b0;
end
else
begin
if (~axi_wready && S_AXI_WVALID && S_AXI_AWVALID && aw_en )
begin
// slave is ready to accept write data when
// there is a valid write address and write data
// on the write address and data bus. This design
// expects no outstanding transactions.
axi_wready <= 1'b1;
end
else
begin
axi_wready <= 1'b0;
end
end
end
// Implement memory mapped register select and write logic generation
// The write data is accepted and written to memory mapped registers when
// axi_awready, S_AXI_WVALID, axi_wready and S_AXI_WVALID are asserted. Write strobes are used to
// select byte enables of slave registers while writing.
// These registers are cleared when reset (active low) is applied.
// Slave register write enable is asserted when valid address and data are available
// and the slave is ready to accept the write address and write data.
assign slv_reg_wren = axi_wready && S_AXI_WVALID && axi_awready && S_AXI_AWVALID;
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
load_reg <= 0;
compare_reg <= 0;
control_reg <= 0;
unused_reg <= 0;
end
else begin
if (slv_reg_wren)
begin
case ( axi_awaddr[ADDR_LSB+OPT_MEM_ADDR_BITS:ADDR_LSB] )
2'h0:
for ( byte_index = 0; byte_index <= (C_S_AXI_DATA_WIDTH/8)-1; byte_index = byte_index+1 )
if ( S_AXI_WSTRB[byte_index] == 1 ) begin
// Respective byte enables are asserted as per write strobes
// Slave register 0
load_reg[(byte_index*8) +: 8] <= S_AXI_WDATA[(byte_index*8) +: 8];
end
2'h1:
for ( byte_index = 0; byte_index <= (C_S_AXI_DATA_WIDTH/8)-1; byte_index = byte_index+1 )
if ( S_AXI_WSTRB[byte_index] == 1 ) begin
// Respective byte enables are asserted as per write strobes
// Slave register 1
compare_reg[(byte_index*8) +: 8] <= S_AXI_WDATA[(byte_index*8) +: 8];
end
2'h2:
for ( byte_index = 0; byte_index <= (C_S_AXI_DATA_WIDTH/8)-1; byte_index = byte_index+1 )
if ( S_AXI_WSTRB[byte_index] == 1 ) begin
// Respective byte enables are asserted as per write strobes
// Slave register 2
control_reg[(byte_index*8) +: 8] <= S_AXI_WDATA[(byte_index*8) +: 8];
end
2'h3:
for ( byte_index = 0; byte_index <= (C_S_AXI_DATA_WIDTH/8)-1; byte_index = byte_index+1 )
if ( S_AXI_WSTRB[byte_index] == 1 ) begin
// Respective byte enables are asserted as per write strobes
// Slave register 3
unused_reg[(byte_index*8) +: 8] <= S_AXI_WDATA[(byte_index*8) +: 8];
end
default : begin
load_reg <= load_reg;
compare_reg <= compare_reg;
control_reg <= control_reg;
unused_reg <= unused_reg;
end
endcase
end
end
end
// Implement write response logic generation
// The write response and response valid signals are asserted by the slave
// when axi_wready, S_AXI_WVALID, axi_wready and S_AXI_WVALID are asserted.
// This marks the acceptance of address and indicates the status of
// write transaction.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_bvalid <= 0;
axi_bresp <= 2'b0;
end
else
begin
if (axi_awready && S_AXI_AWVALID && ~axi_bvalid && axi_wready && S_AXI_WVALID)
begin
// indicates a valid write response is available
axi_bvalid <= 1'b1;
axi_bresp <= 2'b0; // 'OKAY' response
end // work error responses in future
else
begin
if (S_AXI_BREADY && axi_bvalid)
//check if bready is asserted while bvalid is high)
//(there is a possibility that bready is always asserted high)
begin
axi_bvalid <= 1'b0;
end
end
end
end
// Implement axi_arready generation
// axi_arready is asserted for one S_AXI_ACLK clock cycle when
// S_AXI_ARVALID is asserted. axi_awready is
// de-asserted when reset (active low) is asserted.
// The read address is also latched when S_AXI_ARVALID is
// asserted. axi_araddr is reset to zero on reset assertion.
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_arready <= 1'b0;
axi_araddr <= 32'b0;
end
else
begin
if (~axi_arready && S_AXI_ARVALID)
begin
// indicates that the slave has acceped the valid read address
axi_arready <= 1'b1;
// Read address latching
axi_araddr <= S_AXI_ARADDR;
end
else
begin
axi_arready <= 1'b0;
end
end
end
// Implement axi_arvalid generation
// axi_rvalid is asserted for one S_AXI_ACLK clock cycle when both
// S_AXI_ARVALID and axi_arready are asserted. The slave registers
// data are available on the axi_rdata bus at this instance. The
// assertion of axi_rvalid marks the validity of read data on the
// bus and axi_rresp indicates the status of read transaction.axi_rvalid
// is deasserted on reset (active low). axi_rresp and axi_rdata are
// cleared to zero on reset (active low).
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_rvalid <= 0;
axi_rresp <= 0;
end
else
begin
if (axi_arready && S_AXI_ARVALID && ~axi_rvalid)
begin
// Valid read data is available at the read data bus
axi_rvalid <= 1'b1;
axi_rresp <= 2'b0; // 'OKAY' response
end
else if (axi_rvalid && S_AXI_RREADY)
begin
// Read data is accepted by the master
axi_rvalid <= 1'b0;
end
end
end
// Implement memory mapped register select and read logic generation
// Slave register read enable is asserted when valid address is available
// and the slave is ready to accept the read address.
assign slv_reg_rden = axi_arready & S_AXI_ARVALID & ~axi_rvalid;
always @(*)
begin
// Address decoding for reading registers
case ( axi_araddr[ADDR_LSB+OPT_MEM_ADDR_BITS:ADDR_LSB] )
2'h0 : reg_data_out <= load_reg;
2'h1 : reg_data_out <= compare_reg;
2'h2 : reg_data_out <= control_reg;
2'h3 : reg_data_out <= unused_reg;
default : reg_data_out <= 0;
endcase
end
// Output register or memory read data
always @( posedge S_AXI_ACLK )
begin
if ( S_AXI_ARESETN == 1'b0 )
begin
axi_rdata <= 0;
end
else
begin
// When there is a valid read address (S_AXI_ARVALID) with
// acceptance of read address by the slave (axi_arready),
// output the read dada
if (slv_reg_rden)
begin
axi_rdata <= reg_data_out; // register read data
end
end
end
// Add user logic here
pwm_gen #(.WIDTH(C_S_AXI_DATA_WIDTH)) pwm (
.clk(S_AXI_ACLK),
.rst(S_AXI_ARESETN),
.load(load_reg),
.compare(compare_reg),
.control(control_reg),
.pwm_out(pwm_out)
);
// User logic ends
endmodule
SDK
共2个文件。用于SDK开发，提供了头文件和代码示例。
PWM_Generator.h
#ifndef PWM_GENERATOR_H
#define PWM_GENERATOR_H
/****************** Include Files ********************/
#include "xil_types.h"
#include "xstatus.h"
#include "xil_io.h"
#define PWM_GENERATOR_S_AXI_LOAD_REG_OFFSET 0
#define PWM_GENERATOR_S_AXI_COMPARE_REG_OFFSET 4
#define PWM_GENERATOR_S_AXI_CONTROL_REG_OFFSET 8
#define PWM_GENERATOR_S_AXI_UNUSED_REG_OFFSET 12
/**************************** Type Definitions *****************************/
/**
*
* Write a value to a PWM_GENERATOR register. A 32 bit write is performed.
* If the component is implemented in a smaller width, only the least
* significant data is written.
*
* @param BaseAddress is the base address of the PWM_GENERATORdevice.
* @param RegOffset is the register offset from the base to write to.
* @param Data is the data written to the register.
*
* @return None.
*
* @note
* C-style signature:
* void PWM_GENERATOR_mWriteReg(u32 BaseAddress, unsigned RegOffset, u32 Data)
*
*/
#define PWM_GENERATOR_mWriteReg(BaseAddress, RegOffset, Data) \
Xil_Out32((BaseAddress) + (RegOffset), (u32)(Data))
/**
*
* Read a value from a PWM_GENERATOR register. A 32 bit read is performed.
* If the component is implemented in a smaller width, only the least
* significant data is read from the register. The most significant data
* will be read as 0.
*
* @param BaseAddress is the base address of the PWM_GENERATOR device.
* @param RegOffset is the register offset from the base to write to.
*
* @return Data is the data from the register.
*
* @note
* C-style signature:
* u32 PWM_GENERATOR_mReadReg(u32 BaseAddress, unsigned RegOffset)
*
*/
#define PWM_GENERATOR_mReadReg(BaseAddress, RegOffset) \
Xil_In32((BaseAddress) + (RegOffset))
// Enables PWM Output by setting bit 0 of the control register
#define PWM_GENERATOR_mEnableOutput(BaseAddress) \
PWM_GENERATOR_mWriteReg(BaseAddress, PWM_GENERATOR_S_AXI_CONTROL_REG_OFFSET, 1)
// Disables PWM Output by clearing bit 0 of the control register
#define PWM_GENERATOR_mDisableOutput(BaseAddress) \
PWM_GENERATOR_mWriteReg(BaseAddress, PWM_GENERATOR_S_AXI_CONTROL_REG_OFFSET, 0)
// Sets the PWM Generator's load value
#define PWM_GENERATOR_mSetLoad(BaseAddress, Load) \
PWM_GENERATOR_mWriteReg(BaseAddress, PWM_GENERATOR_S_AXI_LOAD_REG_OFFSET, Load)
// Sets the PWM Generator's compare value
#define PWM_GENERATOR_mSetCompare(BaseAddress, Compare) \
PWM_GENERATOR_mWriteReg(BaseAddress, PWM_GENERATOR_S_AXI_COMPARE_REG_OFFSET, Compare)
/************************** Function Prototypes ****************************/
/**
*
* Run a self-test on the driver/device. Note this may be a destructive test if
* resets of the device are performed.
*
* If the hardware system is not built correctly, this function may never
* return to the caller.
*
* @param baseaddr_p is the base address of the PWM_GENERATOR instance to be worked on.
*
* @return
*
* - XST_SUCCESS if all self-test code passed
* - XST_FAILURE if any self-test code failed
*
* @note Caching must be turned off for this function to work.
* @note Self test may fail if data memory and device are not on the same bus.
*
*/
XStatus PWM_GENERATOR_Reg_SelfTest(void * baseaddr_p);
#endif // PWM_GENERATOR_H
main.c
#include "xparameters.h"
#include "PWM_Generator.h"
/*pwm generator AXI base address*/
#define XPAR_PWM_GENERATOR_0_S00_AXI_BASEADDR 0x43c00000
int main(void)
{
/*
The default clock period for zynq is 10ns.
In this example, my servo is controlled by pwm,
and the period of this servo is 20ms, so I set prd as 2000000.
20ms = 2000000 * 10ns
*/
int prd = 2000000;
PWM_GENERATOR_mDisableOutput(XPAR_PWM_GENERATOR_0_S00_AXI_BASEADDR);
PWM_GENERATOR_mSetLoad(XPAR_PWM_GENERATOR_0_S00_AXI_BASEADDR, prd);
PWM_GENERATOR_mSetCompare(XPAR_PWM_GENERATOR_0_S00_AXI_BASEADDR, 150000); // set the duty cycle
PWM_GENERATOR_mEnableOutput(XPAR_PWM_GENERATOR_0_S00_AXI_BASEADDR);
while(1)
return 0;
}
使用方式
- 新建工程
- Create Block Design，（我起名为example），添加zynq作为PS
- 将HDL中的3个文件导入自己的Design Source中，然后将其点击拖动到右边的block design中会自动添加为RTL模块，再点击自动连线就得到下图的结果。
- Generate Output Product，最好使用Global能避免很多报错
- Create HDL Wrapper
- 将example_wrapper set as top
-
最终得到文件结构如下图
-
根据自己的需求约束引脚，生成bitstream，导出hardware，并勾选include bitstream，启动SDK就可开始SDK开发
- SDK中创建application，将PWM_Generator.h头文件复制粘贴进自己的application中，至于具体的开发可参照main.c
