diff --git a/components/driver/sdio_slave.c b/components/driver/sdio_slave.c index 8402878de..2849e412f 100644 --- a/components/driver/sdio_slave.c +++ b/components/driver/sdio_slave.c @@ -187,7 +187,7 @@ typedef struct { /*------- receiving ---------------*/ buf_stailq_t recv_link_list; // now ready to/already hold data buf_tailq_t recv_reg_list; // removed from the link list, registered but not used now - buf_desc_t* recv_cur_ret; + volatile buf_desc_t* recv_cur_ret; // next desc to return, NULL if all loaded descriptors are returned portMUX_TYPE recv_spinlock; } sdio_context_t; @@ -1137,8 +1137,6 @@ static void sdio_intr_recv(void* arg) portBASE_TYPE yield = 0; if ( SLC.slc0_int_raw.tx_done ) { SLC.slc0_int_clr.tx_done = 1; - assert( context.recv_cur_ret != NULL ); - while ( context.recv_cur_ret && context.recv_cur_ret->owner == 0 ) { // This may cause the ``cur_ret`` pointer to be NULL, indicating the list is empty, // in this case the ``tx_done`` should happen no longer until new desc is appended. @@ -1163,15 +1161,24 @@ esp_err_t sdio_slave_recv_load_buf(sdio_slave_buf_handle_t handle) desc->owner = 1; desc->not_receiving = 0; //manually remove the prev link (by set not_receiving=0), to indicate this is in the queue - // 1. If all desc are returned in the ISR, the pointer is moved to NULL. The pointer is set to the newly appended desc here. - // 2. If the pointer is move to some not-returned desc (maybe the one appended here), do nothing. - // The ``cur_ret`` pointer must be checked and set after new desc appended to the list, or the pointer setting may fail. + buf_desc_t *const tail = STAILQ_LAST(queue, buf_desc_s, qe); + STAILQ_INSERT_TAIL( queue, desc, qe ); - if ( context.recv_cur_ret == NULL ) { + if (tail == NULL || (tail->owner == 0)) { + //in this case we have to set the ret pointer + if (tail != NULL) { + /* if the owner of the tail is returned to the software, the ISR is + * expect to write this pointer to NULL in a short time, wait until + * that and set new value for this pointer + */ + while (context.recv_cur_ret != NULL) {} + } + assert(context.recv_cur_ret == NULL); context.recv_cur_ret = desc; } + assert(context.recv_cur_ret != NULL); - if ( desc == STAILQ_FIRST(queue) ) { + if (tail == NULL) { //no one in the ll, start new ll operation. SLC.slc0_tx_link.addr = (uint32_t)desc; SLC.slc0_tx_link.start = 1;