diff options
Diffstat (limited to 'examples/vf6xx_colibri_m4/demo_apps/rpmsg/str_echo/rpmsg_str_echo.c')
| -rw-r--r-- | examples/vf6xx_colibri_m4/demo_apps/rpmsg/str_echo/rpmsg_str_echo.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/examples/vf6xx_colibri_m4/demo_apps/rpmsg/str_echo/rpmsg_str_echo.c b/examples/vf6xx_colibri_m4/demo_apps/rpmsg/str_echo/rpmsg_str_echo.c new file mode 100644 index 0000000..38c6c11 --- /dev/null +++ b/examples/vf6xx_colibri_m4/demo_apps/rpmsg/str_echo/rpmsg_str_echo.c @@ -0,0 +1,207 @@ +/* + * Copyright (c) 2016, Toradex AG + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * + * o Redistributions of source code must retain the above copyright notice, this list + * of conditions and the following disclaimer. + * + * o Redistributions in binary form must reproduce the above copyright notice, this + * list of conditions and the following disclaimer in the documentation and/or + * other materials provided with the distribution. + * + * o Neither the name of Freescale Semiconductor, Inc. nor the names of its + * contributors may be used to endorse or promote products derived from this + * software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR + * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <stdio.h> +#include <errno.h> + +#include "FreeRTOS.h" +#include "task.h" +#include "semphr.h" +#include "string.h" +#include "assert.h" +#include "rpmsg/rpmsg.h" +#include "plat_porting.h" +#include <ccm_vf6xx.h> +#include "debug_console_vf6xx.h" + +#define MAX_STRING_SIZE 496 /* Maximum size to hold the data A7 gives */ + +/* + * For the most worst case, master will send 3 consecutive messages which remote + * do not process. + * The synchronization between remote and master is that each time endpoint callback + * is called, the MU Receive interrupt is temperorily disabled. Until the next time + * remote consumes the message, the interrupt will not be enabled again. + * When the interrupt is not enabled, Master can not send the notify, it will blocks + * there and can not send further message. + * In the worst case, master send the first message, it triggles the ISR in remote + * side, remote ISR clear the MU status bit so master can send the second message + * and notify again, master can continue to send the 3rd message but will blocks + * when trying to notify. Meanwhile, remote side is still in the first ISR which + * has a loop to receive all the 3 messages. + * Master is blocked and can not send the 4th message, remote side ISR copies all + * this 3 message to app buffer and informs the app layer to consume them. After + * a message is consumed, the ISR is enabled again and the second notify is received. + * This unblocks the master to complete the 3rd notify and send the next message. + * The 4th notify will not complete until remote consumes the second message. + * The situation goes on and we can see application layer need a maximum size 3 + * buffer to hold the unconsumed messages. STRING_BUFFER_CNT is therefore set to 3 + */ +#define STRING_BUFFER_CNT 3 + +/* + * APP decided interrupt priority + */ +#define APP_MSCM_IRQ_PRIORITY 3 + +/* Internal functions */ +static void rpmsg_channel_created(struct rpmsg_channel *rp_chnl); +static void rpmsg_channel_deleted(struct rpmsg_channel *rp_chnl); +static void rpmsg_read_cb(struct rpmsg_channel *, void *, int, void *, unsigned long); + +/* Globals */ +static struct remote_device *rdev; +static struct rpmsg_channel *app_chnl; +static char strVar[STRING_BUFFER_CNT][MAX_STRING_SIZE + 1]; +static uint8_t app_idx = 0; +static uint8_t handler_idx = 0; +static SemaphoreHandle_t app_sema; + +/*! + * @brief A basic RPMSG task + */ +void StrEchoTask(void *pvParameters) +{ + printf("RPMSG String Echo Demo...\r\n"); + + app_sema = xSemaphoreCreateCounting(STRING_BUFFER_CNT + 1, 0); + + printf("RPMSG Init as Remote\r\n"); + /* + * RPMSG Init as REMOTE + */ + rpmsg_init(0, &rdev, rpmsg_channel_created, rpmsg_channel_deleted, rpmsg_read_cb, RPMSG_MASTER); + + /* + * rpmsg_channel_created will post the first semaphore + */ + xSemaphoreTake(app_sema, portMAX_DELAY); + printf("Name service handshake is done, M4 has setup a rpmsg channel [%d ---> %d]\r\n", app_chnl->src, app_chnl->dst); + + + /* + * pingpong demo loop + */ + for (;;) { + xSemaphoreTake(app_sema, portMAX_DELAY); + /* + * Take from next app string buffer + */ + if ((strlen(strVar[app_idx]) == 2) && (strVar[app_idx][0] == 0xd) && (strVar[app_idx][1] == 0xa)) + printf("Get New Line From A7 From Slot %d\r\n", app_idx); + else + printf("Get Message From A7 : \"%s\" [len : %d] from slot %d\r\n", strVar[app_idx], strlen(strVar[app_idx]), app_idx); + + /* + * echo back + */ + rpmsg_send(app_chnl, (void*)strVar[app_idx], strlen(strVar[app_idx])); + app_idx = (app_idx + 1) % STRING_BUFFER_CNT; + /* + * once a message is consumed, the MSCM receive interrupt can be enabled + * again + */ + platform_interrupt_enable(); + } +} + +int main(void) +{ + /* Init Clock Control and UART */ + CCM_GetClocks(); + CCM_ControlGate(ccmCcgrGateUart2, ccmClockNeededAll); + + vf6xx_DbgConsole_Init(UART2, ccmIpgBusClk, 115200); + + printf("Starting RPMSG PingPong Demo...\r\n"); + + /* + * Prepare for the MSCM Interrupt + * MSCM must be initialized before rpmsg init is called + */ + platform_interrupt_enable(); + NVIC_SetPriority(CPU2CPU_INT0_IRQ, APP_MSCM_IRQ_PRIORITY); + NVIC_SetPriority(CPU2CPU_INT1_IRQ, APP_MSCM_IRQ_PRIORITY); + + + // Create a demo task which will print Hello world and echo user's input. + xTaskCreate(StrEchoTask, "String Echo Task", configMINIMAL_STACK_SIZE, + NULL, tskIDLE_PRIORITY+1, NULL); + + // Start FreeRTOS scheduler. + vTaskStartScheduler(); + + // Should never reach this point. + while (true); +} + +/* rpmsg_rx_callback will call into this for a channel creation event*/ +static void rpmsg_channel_created(struct rpmsg_channel *rp_chnl) +{ + /* + * we should give the created rp_chnl handler to app layer + */ + app_chnl = rp_chnl; + + /* + * sync to application layer + */ + xSemaphoreGiveFromISR(app_sema, NULL); +} + +static void rpmsg_channel_deleted(struct rpmsg_channel *rp_chnl) +{ + rpmsg_destroy_ept(rp_chnl->rp_ept); +} + +static void rpmsg_read_cb(struct rpmsg_channel *rp_chnl, void *data, int len, + void * priv, unsigned long src) +{ + /* + * Temperorily Disable MSCM Receive Interrupt to avoid master + * sending too many messages and remote will fail to keep pace + * to consume + */ + platform_interrupt_disable(); + /* + * Copy to next app string buffer + */ + assert(len <= MAX_STRING_SIZE); + memcpy((void*)strVar[handler_idx], data, len); + /* + * Add trailing '\0' + */ + strVar[handler_idx][len] = 0; + handler_idx = (handler_idx + 1) % STRING_BUFFER_CNT; + xSemaphoreGiveFromISR(app_sema, NULL); +} +/******************************************************************************* + * EOF + ******************************************************************************/ |