AM2634: How to send 512 bytes of data to another core

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#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include <kernel/dpl/ClockP.h>
#include <kernel/dpl/DebugP.h>
#include <drivers/ipc_notify.h>
#include <drivers/ipc_rpmsg.h>
#include "ti_drivers_open_close.h"
#include "ti_board_open_close.h"

/* This example shows message exchange between multiple cores.
 *
 * One of the core is designated as the 'main' core
 * and other cores are designated as `remote` cores.
 *
 * The main core initiates IPC with remote core's by sending it a message.
 * The remote cores echo the same message to the main core.
 *
 * The main core repeats this for gMsgEchoCount iterations.
 *
 * In each iteration of message exchange, the message value is incremented.
 *
 * When iteration count reaches gMsgEchoCount, the example is completed.
 *
 */

/* number of iterations of message exchange to do */
uint32_t gMsgEchoCount = 1u;

#if defined(SOC_AM243X)
/* main core that starts the message exchange */
uint32_t gMainCoreId = CSL_CORE_ID_R5FSS0_0;
/* remote cores that echo messages from main core, make sure to NOT list main core in this list */
uint32_t gRemoteCoreId[] = {
    CSL_CORE_ID_M4FSS0_0,
    CSL_CORE_ID_R5FSS0_1,
    CSL_CORE_ID_R5FSS1_0,
    CSL_CORE_ID_R5FSS1_1,
    CSL_CORE_ID_MAX /* this value indicates the end of the array */
};
#endif

#if defined (SOC_AM263X) || defined (SOC_AM263PX)
/* main core that starts the message exchange */
uint32_t gMainCoreId = CSL_CORE_ID_R5FSS0_0;
/* remote cores that echo messages from main core, make sure to NOT list main core in this list */
uint32_t gRemoteCoreId[] = {
    CSL_CORE_ID_R5FSS0_1,
    CSL_CORE_ID_R5FSS1_0,
    CSL_CORE_ID_R5FSS1_1,
    CSL_CORE_ID_MAX /* this value indicates the end of the array */
};
#endif

#if defined(SOC_AM64X)
/* main core that starts the message exchange */
uint32_t gMainCoreId = CSL_CORE_ID_R5FSS0_0;
/* remote cores that echo messages from main core, make sure to NOT list main core in this list */
uint32_t gRemoteCoreId[] = {
    CSL_CORE_ID_M4FSS0_0,
    CSL_CORE_ID_R5FSS0_1,
    CSL_CORE_ID_R5FSS1_0,
    CSL_CORE_ID_R5FSS1_1,
    CSL_CORE_ID_A53SS0_0,
    CSL_CORE_ID_MAX /* this value indicates the end of the array */
};
#endif

#if defined(SOC_AM273X) || defined(SOC_AWR294X)
/* main core that starts the message exchange */
uint32_t gMainCoreId = CSL_CORE_ID_R5FSS0_0;
/* remote cores that echo messages from main core, make sure to NOT list main core in this list */
uint32_t gRemoteCoreId[] = {
    CSL_CORE_ID_R5FSS0_1,
    CSL_CORE_ID_C66SS0,
    CSL_CORE_ID_MAX /* this value indicates the end of the array */
};
#endif

#if defined(SOC_AM261X)
/* main core that starts the message exchange */
uint32_t gMainCoreId = CSL_CORE_ID_R5FSS0_0;
/* remote cores that echo messages from main core, make sure to NOT list main core in this list */
uint32_t gRemoteCoreId[] = {
    CSL_CORE_ID_R5FSS0_1,
    CSL_CORE_ID_MAX /* this value indicates the end of the array */
};
#endif

/*
 * Remote core service end point
 *
 * pick any unique value on that core between 0..RPMESSAGE_MAX_LOCAL_ENDPT-1
 * the value need not be unique across cores
 */
uint16_t gRemoteServiceEndPt = 13u;

/* maximum size that message can have in this example */
#define MAX_MSG_SIZE        (512u)

/* Main core ack reply end point
 *
 * pick any unique value on that core between 0..RPMESSAGE_MAX_LOCAL_ENDPT-1
 * the value need not be unique across cores
 */
#define MAIN_CORE_ACK_REPLY_END_PT  (12U)

/* RPMessage_Object MUST be global or static */
RPMessage_Object gAckReplyMsgObject;

void ipc_rpmsg_echo_main_core_start(void)
{
    RPMessage_CreateParams createParams;
    uint32_t msg, i, numRemoteCores;
    uint64_t curTime;
    char msgBuf[MAX_MSG_SIZE];
    int32_t status;
    uint16_t remoteCoreId, remoteCoreEndPt, msgSize;

    for (uint16_t i=0; i<MAX_MSG_SIZE; i++)
    {
        msgBuf[i] = i;
    }

    RPMessage_CreateParams_init(&createParams);
    createParams.localEndPt = MAIN_CORE_ACK_REPLY_END_PT;
    status = RPMessage_construct(&gAckReplyMsgObject, &createParams);
    DebugP_assert(status==SystemP_SUCCESS);

    numRemoteCores = 0;
    for(i=0; gRemoteCoreId[i]!=CSL_CORE_ID_MAX; i++)
    {
        numRemoteCores++;
    }

    /* wait for all cores to be ready */
    IpcNotify_syncAll(SystemP_WAIT_FOREVER);

    ClockP_usleep(500*1000); /* wait for log messages from remote cores to be flushed, otherwise this delay is not needed */

    DebugP_log("[IPC RPMSG ECHO] Message exchange started by main core !!!\r\n");

    curTime = ClockP_getTimeUsec();

    for(msg=0; msg<gMsgEchoCount; msg++)
    {
        // snprintf(msgBuf, MAX_MSG_SIZE-1, "%" PRIu32, msg);
        // msgBuf[MAX_MSG_SIZE-1] = 0;
        // msgSize = strlen(msgBuf) + 1; /* count the terminating char as well */

        /* send the same messages to all cores */
        for(i=0; gRemoteCoreId[i]!=CSL_CORE_ID_MAX; i++ )
        {
            status = RPMessage_send(
                msgBuf, msgSize,
                gRemoteCoreId[i], gRemoteServiceEndPt,
                RPMessage_getLocalEndPt(&gAckReplyMsgObject),
                SystemP_WAIT_FOREVER);
            DebugP_assert(status==SystemP_SUCCESS);
        }
        /* wait for response from all cores */
        for(i=0; gRemoteCoreId[i]!=CSL_CORE_ID_MAX; i++ )
        {
            /* set 'msgSize' to size of recv buffer,
            * after return `msgSize` contains actual size of valid data in recv buffer
            */
            msgSize = sizeof(msgBuf);
            status = RPMessage_recv(&gAckReplyMsgObject,
                msgBuf, &msgSize,
                &remoteCoreId, &remoteCoreEndPt,
                SystemP_WAIT_FOREVER);
            DebugP_assert(status==SystemP_SUCCESS);
        }
    }

    curTime = ClockP_getTimeUsec() - curTime;

    DebugP_log("[IPC RPMSG ECHO] All echoed messages received by main core from %d remote cores !!!\r\n", numRemoteCores);
    DebugP_log("[IPC RPMSG ECHO] Messages sent to each core = %d \r\n", gMsgEchoCount);
    DebugP_log("[IPC RPMSG ECHO] Number of remote cores = %d \r\n", numRemoteCores);
    DebugP_log("[IPC RPMSG ECHO] Total execution time = %" PRId64 " usecs\r\n", curTime);
    DebugP_log("[IPC RPMSG ECHO] One way message latency = %" PRId32 " nsec\r\n",
        (uint32_t)(curTime*1000u/(gMsgEchoCount*numRemoteCores*2)));

    RPMessage_destruct(&gAckReplyMsgObject);

    DebugP_log("All tests have passed!!\r\n");
}

/* RPMessage_Object MUST be global or static */
static RPMessage_Object gRecvMsgObject;

void ipc_rpmsg_echo_remote_core_start(void)
{
    int32_t status;
    RPMessage_CreateParams createParams;
    char recvMsg[MAX_MSG_SIZE];
    uint16_t recvMsgSize, remoteCoreId, remoteCoreEndPt;

    RPMessage_CreateParams_init(&createParams);
    createParams.localEndPt = gRemoteServiceEndPt;
    status = RPMessage_construct(&gRecvMsgObject, &createParams);
    DebugP_assert(status==SystemP_SUCCESS);

    /* wait for all cores to be ready */
    IpcNotify_syncAll(SystemP_WAIT_FOREVER);

    DebugP_log("[IPC RPMSG ECHO] Remote Core waiting for messages from main core ... !!!\r\n");

    /* wait for messages forever in a loop */
    while(1)
    {
        /* set 'recvMsgSize' to size of recv buffer,
        * after return `recvMsgSize` contains actual size of valid data in recv buffer
        */
        recvMsgSize = sizeof(recvMsg);
        status = RPMessage_recv(&gRecvMsgObject,
            recvMsg, &recvMsgSize,
            &remoteCoreId, &remoteCoreEndPt,
            SystemP_WAIT_FOREVER);
        DebugP_assert(status==SystemP_SUCCESS);

        /* echo the same message string as reply */

        /* send ack to sender CPU at the sender end point */
        status = RPMessage_send(
            recvMsg, recvMsgSize,
            remoteCoreId, remoteCoreEndPt,
            RPMessage_getLocalEndPt(&gRecvMsgObject),
            SystemP_WAIT_FOREVER);
        DebugP_assert(status==SystemP_SUCCESS);
    }
    /* This loop will never exit */
}

void ipc_rpmsg_echo_main(void *args)
{
    Drivers_open();
    Board_driversOpen();

    if(IpcNotify_getSelfCoreId()==gMainCoreId)
    {
        ipc_rpmsg_echo_main_core_start();
    }
    else
    {
        ipc_rpmsg_echo_remote_core_start();
    }

    Board_driversClose();
    /* We dont close drivers to let the UART driver remain open and flush any pending messages to console */
    /* Drivers_close(); */
}