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Diffstat (limited to 'examples/imx7d_val_m4/demo_apps/rpmsg/str_echo_bm/str_echo_bm.c')
| -rw-r--r-- | examples/imx7d_val_m4/demo_apps/rpmsg/str_echo_bm/str_echo_bm.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/examples/imx7d_val_m4/demo_apps/rpmsg/str_echo_bm/str_echo_bm.c b/examples/imx7d_val_m4/demo_apps/rpmsg/str_echo_bm/str_echo_bm.c new file mode 100644 index 0000000..c96d505 --- /dev/null +++ b/examples/imx7d_val_m4/demo_apps/rpmsg/str_echo_bm/str_echo_bm.c @@ -0,0 +1,205 @@ +/* + * Copyright (c) 2015, Freescale Semiconductor, Inc. + * 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 "rpmsg/rpmsg_ext.h" +#include "string.h" +#include "assert.h" +#include "board.h" +#include "mu_imx.h" +#include "debug_console_imx.h" + +/* + * APP decided interrupt priority + */ +#define APP_MU_IRQ_PRIORITY 3 + +/* + * 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 stores all + * this 3 messages to app buffer and informs the app layer to consume them. After + * 3 messages are consumed, the ISR is enabled again and the second notify is received. + * This unblocks the master to complete the 3rd notify and send the 4th 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 + +typedef struct +{ + unsigned long src; + void* data; + int len; +} app_message_t; + +/* Globals */ +static struct rpmsg_channel *app_chnl = NULL; +static app_message_t app_msg[STRING_BUFFER_CNT]; +static char app_buf[512]; /* Each RPMSG buffer can carry less than 512 payload */ +static uint8_t app_idx = 0; +static uint8_t handler_idx = 0; +static volatile int32_t msg_count = 0; + +static void rpmsg_enable_rx_int(bool enable) +{ + if (enable) + { + if ((--msg_count) == 0) + MU_EnableRxFullInt(MUB, RPMSG_MU_CHANNEL); + } + else + { + if ((msg_count++) == 0) + MU_DisableRxFullInt(MUB, RPMSG_MU_CHANNEL); + } +} + +static void rpmsg_read_cb(struct rpmsg_channel *rp_chnl, void *data, int len, + void * priv, unsigned long src) +{ + /* + * Temperorily Disable MU Receive Interrupt to avoid master + * sending too many messages and remote will fail to keep pace + * to consume (flow control) + */ + rpmsg_enable_rx_int(false); + + /* Hold the RPMsg rx buffer to be used in main loop */ + rpmsg_hold_rx_buffer(rp_chnl, data); + app_msg[handler_idx].src = src; + app_msg[handler_idx].data = data; + app_msg[handler_idx].len = len; + + /* Move to next free message index */ + handler_idx = (handler_idx + 1) % STRING_BUFFER_CNT; +} + +/* 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; + + PRINTF("Name service handshake is done, M4 has setup a rpmsg channel [%d ---> %d]\r\n", app_chnl->src, app_chnl->dst); +} + +static void rpmsg_channel_deleted(struct rpmsg_channel *rp_chnl) +{ +} + +/* + * MU Interrrupt ISR + */ +void BOARD_MU_HANDLER(void) +{ + /* + * calls into rpmsg_handler provided by middleware + */ + rpmsg_handler(); +} + +/*! + * @brief Main function + */ +int main(void) +{ + struct remote_device *rdev; + int len; + void *tx_buf; + unsigned long size; + + hardware_init(); + + /* + * Prepare for the MU Interrupt + * MU must be initialized before rpmsg init is called + */ + MU_Init(BOARD_MU_BASE_ADDR); + NVIC_SetPriority(BOARD_MU_IRQ_NUM, APP_MU_IRQ_PRIORITY); + NVIC_EnableIRQ(BOARD_MU_IRQ_NUM); + + /* Print the initial banner */ + PRINTF("\r\nRPMSG String Echo Bare Metal Demo...\r\n"); + + /* RPMSG Init as REMOTE */ + PRINTF("RPMSG Init as Remote\r\n"); + rpmsg_init(0, &rdev, rpmsg_channel_created, rpmsg_channel_deleted, rpmsg_read_cb, RPMSG_MASTER); + + /* + * str_echo demo loop + */ + for (;;) + { + /* Wait message to be available */ + while (msg_count == 0) + { + } + + /* Copy string from RPMsg rx buffer */ + len = app_msg[app_idx].len; + assert(len < sizeof(app_buf)); + memcpy(app_buf, app_msg[app_idx].data, len); + app_buf[len] = 0; /* End string by '\0' */ + + if ((len == 2) && (app_buf[0] == 0xd) && (app_buf[1] == 0xa)) + PRINTF("Get New Line From Master Side From Slot %d\r\n", app_idx); + else + PRINTF("Get Message From Master Side : \"%s\" [len : %d] from slot %d\r\n", app_buf, len, app_idx); + + /* Get tx buffer from RPMsg */ + tx_buf = rpmsg_alloc_tx_buffer(app_chnl, &size, RPMSG_TRUE); + assert(tx_buf); + /* Copy string to RPMsg tx buffer */ + memcpy(tx_buf, app_buf, len); + /* Echo back received message with nocopy send */ + rpmsg_sendto_nocopy(app_chnl, tx_buf, len, app_msg[app_idx].src); + + /* Release held RPMsg rx buffer */ + rpmsg_release_rx_buffer(app_chnl, app_msg[app_idx].data); + app_idx = (app_idx + 1) % STRING_BUFFER_CNT; + + /* Once a message is consumed, minus the msg_count and might enable MU interrupt again */ + rpmsg_enable_rx_int(true); + } +} + +/******************************************************************************* + * EOF + ******************************************************************************/ |