OMAPL多核通信有三个主要机制，Notify,MessageQ,RegionShare;这里主要利用了Notify机制进行通信控制。
要做一个什么实验？
简单的说，ARM跑一个界面上面有一些按钮，DSP负责驱动AD9833产生正弦、方波和三角波，写入频率信息。这个实验结构是一个经典的单向的传输结构，由用户触发ARM跑的界面上的按钮，发出消息通知DSP，DSP控制AD9833产生波形，写入频率字等信息。
那么ARM的Linux端首选Qt，DSP端的程序使用SYSLINK/BIOS实施操作系统，IPC通讯组件使用Notify。
视频预览：
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多核通信工程目录结构
几个文件，arm，dsp，run，shared，还有makefile文件，makefile文件自己要会修改。
DSP端程序
DSP端程序对于用户来讲ad9833_dev.c ad9833_server.c main.c 三个主要的文件，
- ad9833_dev.c 为AD9833底层驱动，负责写时序，写参数的
- ad9833_server.c 相当于以太网scoket通信因子，负责进行多核通信和调用dev中的api的
- main.c 为dspbios启动，初始化操作。
环境搭建正确之后，最核心的就是这三个东西，对还有个makefile要配置正确。我在环境调试的时间花的比开发时间多的多，最重要的就是要环境配置正确，库啊，路径啊，这类的。
AD9833底层驱动-ad9833_dev.c
我们这里给出接口函数目录，具体实现不给出：
enum ad9833_wavetype_t{
SIN,SQU,TRI
};
struct ad9833_hw_t {
uint16 clk;
uint16 sdi;
uint16 fsy;
};
// AD9833结构体表述
typedef struct ad9833_t {
struct ad9833_hw_t hw;
struct ad9833_t *self;
enum ad9833_wavetype_t wave_type;
u16 delay;
void (*write_reg)( struct ad9833_t *self, u16 reg_value);
void (*init_device)( struct ad9833_t *self );
void (*set_wave_freq)( struct ad9833_t *self , float freqs_data);
void (*set_wave_type)( struct ad9833_t *self, enum ad9833_wavetype_t wave_type );
void (*set_wave_phase)( struct ad9833_t *self, u16 phase );
void (*set_wave_para)( struct ad9833_t *self, u32 freqs_data, u16 phase, enum ad9833_wavetype_t wave_type );
} AD9833;
// 函数列表
void ad9833_set_para( struct ad9833_t *self,u32 freqs_data, u16 phase, enum ad9833_wavetype_t wave_type );
void ad9833_device_init( struct ad9833_t *self );
void ad9833_write_reg( struct ad9833_t *self, uint16_t data );
void ad9833_delay( struct ad9833_t *self );
void ad9833_gpio_init( void );
void ad9833_set_wave_type( struct ad9833_t *self, enum ad9833_wavetype_t wave_type );
void ad9833_set_phase( struct ad9833_t *self, uint16_t phase );
void ad9833_set_freq( struct ad9833_t *self, float freq );
void ad9833_dev_destroy( AD9833 *dev );
void ad9833_dev_new();
AD9833的驱动，按照手册进行编辑，然后封装成这个样子，这里一定需要有的函数是：
- ad9833_dev_new()
- ad9833_dev_destroy()
这两个函数需要在ad9833_server里面运行。
AD9833这块就不多说了，我们主要来说多核通信这块的知识。
IPC之Notify机制-ad9833_server.c
结构体建立
ad9833_server结构体的建立：
typedef struct ad9833_server_t {
// 3个id
uint8_t host_id;
uint8_t line_id;
uint8_t event_id;
// 连接状态
bool connected;
bool quit;
// 信号量的机制
Semaphore_Struct sem_obj;
Semaphore_Handle sem;
uint32_t payload;
// 底层设备，ad9833_dev.c的驱动结构体
AD9833 *dev;
} AD9833_SERVER ;
* 3个ID
host id： 在BIOS里面有设定
line_id，event_id: 在shared文件夹内有个SystemCfg.h里面定义了这两个ID
/* ti.ipc.Notify system configuration */
#define SystemCfg_LineId 0
#define SystemCfg_EventId 7* 信号量
l提供对共享资源的的互斥访问,最多直接64个独立的信号量,信号量请求方式
——直接方式
——间接方式
——混合方式
l不分大小端
l信号量的原子操作
l锁存模式（信号量被使用时）
l排队等待信号量
l获取信号量时产生中断
l支持信号量状态检测
l错误检测和错误中断
通过以上阅读就可以知道信号量是做什么的了。
* 底层设备
需要通过server结构体的实例化对AD9833实行操控。
服务函数
Notify必不可少的几个函数：
- 事件注册函数：
static void ad9833_server_on_event(**uint16_t proc_id, uint16_t line_id, uint32_t event_id, UArg arg, uint32_t payloa**) - 事件销毁函数：
void ad9833_server_destroy(AD9833_SERVER *server) - 运行函数：
void ad9833_server_run(AD9833_SERVER *server) - 命令接收函数：
static uint32_t ad9833_server_wait_command(AD9833_SERVER *server) - 命令执行函数：
static void ad9833_server_handle_command(AD9833_SERVER *server, uint32_t cmd)
基本上有了这些函数之后，就可以完成对于Notify服务函数的处理：
Ad9833Server *ad9833_server_new( uint16_t host_id, uint16_t line_id, uint32_t event_id )
{
Ad9833Server *server = ( Ad9833Server * )calloc(1,sizeof( Ad9833Server ));
server->host_id = host_id;
server->line_id = line_id;
server->event_id = event_id;
server->quit = false;
server->connected = false;
server->dev = ad9833_dev_new();
Semaphore_Params params;
Semaphore_Params_init( ¶ms );
params.mode = Semaphore_Mode_COUNTING;
Semaphore_construct(&server->sem_obj,0,¶ms);
server->sem = Semaphore_handle(&server->sem_obj);
if( Notify_registerEvent( \
server->host_id, \
server->line_id, \
server->event_id, \
ad9833_server_start_event, \
(UArg)server ) < 0 ) {
printf( "fail to register event in %d:%d(line:event)", server->line_id, server->event_id );
}
return server;
}
static void ad9833_server_start_event( uint16_t proc_id, uint16_t line_id, uint32_t event_id, UArg arg, uint32_t payload )
{
Ad9833Server *server = (Ad9833Server *)arg;
Notify_disableEvent( server->host_id, server->line_id, server->event_id );
//ASSERT( server->payload == APP_CMD_NULL );
server->payload = payload;
Semaphore_post( server->sem );
}
void ad9833_server_destroy( Ad9833Server *self )
{
if( !self ) return;
Notify_unregisterEvent( self->host_id, self->line_id, self->event_id, ad9833_server_start_event, (UArg)self );
Semaphore_destruct(&self->sem_obj);
ad9833_dev_destroy(self->dev);
free(self);
}
void ad9833_server_run( Ad9833Server *self )
{
//ASSERT(self);
printf( "ad9833_server running...\n" );
while( ! self->quit ){
uint32_t cmd = ad9833_server_wait_command( self );
ad9833_server_handle_command( self, cmd );
}
printf( "ad9833 server is stopped!\n" );
}
static uint32_t ad9833_server_wait_command( Ad9833Server *self )
{
Semaphore_pend( self->sem, BIOS_WAIT_FOREVER );
uint32_t cmd = self->payload;
self->payload = APP_CMD_NULL;
Notify_enableEvent( self->host_id, self->line_id, self->event_id );
return cmd;
}static uint32_t ad9833_server_wait_command( Ad9833Server *self )
{
Semaphore_pend( self->sem, BIOS_WAIT_FOREVER );
uint32_t cmd = self->payload;
self->payload = APP_CMD_NULL;
Notify_enableEvent( self->host_id, self->line_id, self->event_id );
return cmd;
}
static void ad9833_server_handle_command( Ad9833Server *self, uint32_t cmd )
{
if( !self->connected && cmd != APP_CMD_CONNECTED ) {
printf( "disconnect client \n" );
}
switch( cmd ) {
case APP_CMD_CONNECTED:
//ASSERT(! self->connected);
//LOG_DEBUG("led client had connected");
self->connected = true;
break;
case APP_CMD_DISCONNECTED:
//ASSERT( self->connected );
self->connected = false;
self->quit = true;
break;
case APP_CMD_SETSINE:
self->dev->set_wave_type( self->dev, SIN );
break;
case APP_CMD_SETSEQ:
self->dev->set_wave_type( self->dev, SQU );
break;
case APP_CMD_SETTRI:
self->dev->set_wave_type( self->dev, TRI );
break;
case APP_CMD_SETFREQ_UP:
self->dev->set_wave_freq( self->dev, current_freq += 10 );
if( current_freq > 50000 ) {
current_freq = 50000;
}
break;
case APP_CMD_SETPHASE_UP:
self->dev->set_wave_phase( self->dev, current_phase += 1 );
if( current_phase > 360 ) {
current_phase = 360;
}
break;
case APP_CMD_SETFREQ_DOWN:
self->dev->set_wave_freq( self->dev, current_freq -= 10 );
if( current_freq < 10 ) {
current_freq = 10;
}
break;
case APP_CMD_SETPHASE_DOWN:
self->dev->set_wave_phase( self->dev, current_phase -= 1 );
if( current_phase < 1 ) {
current_phase = 0;
}
}
}
SYSBIOS启动服务
AD9833 *ad9833_handle;
Int main()
{
Task_Handle task;
Error_Block eb;
System_printf("enter main()\n");
Error_init(&eb);
ad9833_handle = ad9833_dev_new();
task = Task_create(taskFxn, NULL, &eb);
if (task == NULL) {
System_printf("Task_create() failed!\n");
BIOS_exit(0);
}
BIOS_start(); /* does not return */
return(0);
}
Void taskFxn(UArg a0, UArg a1)
{
System_printf("enter taskFxn()\n");
printf("Hello sysbios.\n");
ad9833_handle->set_wave_para( ad9833_handle, 5000, 0, SIN );
Task_sleep(1500);
ad9833_handle->set_wave_type( ad9833_handle, SQU );
Task_sleep(1500);
ad9833_handle->set_wave_type( ad9833_handle, TRI );
Task_sleep(1500);
ad9833_handle->set_wave_freq( ad9833_handle, 1000.0f );
System_printf("exit taskFxn()\n");
}
到此我们就完成了对于多核通信的Notify DSP端程序。
ARM端Qt程序
在ARM端有Qt程序，Qt主程序中对syslink的初始化，需要注册几个事件：
SysLink_setup();
this->m_slave_id = MultiProc_getId("DSP");
if( Ipc_control(this->m_slave_id, Ipc_CONTROLCMD_LOADCALLBACK, NULL ) < 0) {
LOG_ERROR("load callback failed");
}
if( Ipc_control(this->m_slave_id, Ipc_CONTROLCMD_STARTCALLBACK, NULL ) < 0 ) {
LOG_ERROR("start callback failed");
}
m_dev = new ad9833_client( this->m_slave_id, SystemCfg_LineId, SystemCfg_EventId );
if( ! this->m_dev->connect() ) {
LOG_ERROR("failed to connect to led server");
}else {
LOG_DEBUG("connect to led server");
}
需要建立服务函数：
#include "ad9833_client.h"
#include "ti/syslink/Std.h"
#include "ti/ipc/Notify.h"
#include "unistd.h"
#include "log.h"
ad9833_client::ad9833_client(uint16_t slave_id, uint16_t line_id, uint16_t event_id )
: m_slave_id(slave_id),m_line_id(line_id),m_event_id(event_id)
{
}
ad9833_client::~ad9833_client() {
}
bool ad9833_client::connect() {
int status;
do {
LOG_DEBUG("try to connect!\n");
status = Notify_sendEvent( this->m_slave_id, \
this->m_line_id, \
this->m_event_id, \
APP_CMD_CONNECTED, \
TRUE );
if( status != Notify_E_EVTNOTREGISTERED ) {
usleep(100);
}
}while( status == Notify_E_EVTNOTREGISTERED );
if( status != Notify_S_SUCCESS ) {
LOG_ERROR("failed to send connect command\n");
return false;
}
LOG_DEBUG("send connected command");
return true;
}
bool ad9833_client::send_cmd( uint16_t cmd )
{
int status = Notify_sendEvent( this->m_slave_id, \
this->m_line_id, \
this->m_event_id, \
cmd, \
TRUE);
if( status < 0 ) {
LOG_DEBUG("fail to send command: %d", cmd);
return false;
}
LOG_DEBUG("send command: %d", cmd);
return true;
}
bool ad9833_client::disconnect()
{
LOG_DEBUG("disconnect with server");
return this->send_cmd(APP_CMD_DISCONNECTED);
}
bool ad9833_client::set_freq_down()
{
LOG_DEBUG("set freq down with server");
return this->send_cmd(APP_CMD_SETFREQ_DOWN);
}
bool ad9833_client::set_freq_up()
{
LOG_DEBUG("set freq up with server");
return this->send_cmd(APP_CMD_SETFREQ_UP);
}
bool ad9833_client::set_phase_down()
{
LOG_DEBUG("set phase down with server");
return this->send_cmd(APP_CMD_SETPHASE_DOWN);
}
bool ad9833_client::set_phase_up()
{
LOG_DEBUG("set phase up with server");
return this->send_cmd(APP_CMD_SETPHASE_UP);
}
bool ad9833_client::set_wave_type(WAVE_TYPE type)
{
if( type == SIN ) {
LOG_DEBUG("set wave type is sine");
this->send_cmd( APP_CMD_SETSINE );
}else if( type == SQU ) {
LOG_DEBUG("set wave type is squ");
this->send_cmd( APP_CMD_SETSEQ );
}else {
LOG_DEBUG("set wave type is tri");
this->send_cmd( APP_CMD_SETTRI );
}
}
#ifndef AD9833_CLIENT_H
#define AD9833_CLIENT_H
#include "stdint.h"
#include "app_common.h"
typedef enum wave_type_t { SIN=0,SQU,TRI } WAVE_TYPE;
class ad9833_client
{
public:
explicit ad9833_client( uint16_t slave_id, uint16_t line_id, uint16_t event_id );
~ad9833_client();
bool connect();
bool disconnect();
bool set_wave_type( WAVE_TYPE type );
bool set_freq_up();
bool set_freq_down();
bool set_phase_up();
bool set_phase_down();
private:
bool send_cmd( uint16_t cmd );
private:
uint16_t m_slave_id;
uint16_t m_line_id;
uint16_t m_event_id;
};
#endif // AD9833_CLIENT_H
源程序： 链接: https://pan.baidu.com/s/1sxjQ… 密码: ya8g
参考文献
[1] ti/wiki, IPC Users Guide/Notify Module, 19 July 2014, at 13:36
[2] ti/wiki, IPC API-Notify.h File Reference 3.40.00.06, 2015
[3] ti/wiki, SysLink UserGuide/Notify, 24 July 2014, at 09:26.
