gdma: avoid manually start/stop when channel is controled by ETM

components/esp_hw_support/dma/gdma.c

@@ -451,10 +451,10 @@ err:
 
 esp_err_t gdma_start(gdma_channel_handle_t dma_chan, intptr_t desc_base_addr)
 {
-    esp_err_t ret = ESP_OK;
     gdma_pair_t *pair = NULL;
     gdma_group_t *group = NULL;
-    ESP_GOTO_ON_FALSE_ISR(dma_chan, ESP_ERR_INVALID_ARG, err, TAG, "invalid argument");
+    ESP_RETURN_ON_FALSE_ISR(dma_chan, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
+    ESP_RETURN_ON_FALSE_ISR(dma_chan->flags.start_stop_by_etm == false, ESP_ERR_INVALID_STATE, TAG, "channel is controlled by ETM");
     pair = dma_chan->pair;
     group = pair->group;
 
@@ -468,16 +468,15 @@ esp_err_t gdma_start(gdma_channel_handle_t dma_chan, intptr_t desc_base_addr)
     }
     portEXIT_CRITICAL_SAFE(&dma_chan->spinlock);
 
-err:
-    return ret;
+    return ESP_OK;
 }
 
 esp_err_t gdma_stop(gdma_channel_handle_t dma_chan)
 {
-    esp_err_t ret = ESP_OK;
     gdma_pair_t *pair = NULL;
     gdma_group_t *group = NULL;
-    ESP_GOTO_ON_FALSE_ISR(dma_chan, ESP_ERR_INVALID_ARG, err, TAG, "invalid argument");
+    ESP_RETURN_ON_FALSE_ISR(dma_chan, ESP_ERR_INVALID_ARG, TAG, "invalid argument");
+    ESP_RETURN_ON_FALSE_ISR(dma_chan->flags.start_stop_by_etm == false, ESP_ERR_INVALID_STATE, TAG, "channel is controlled by ETM");
     pair = dma_chan->pair;
     group = pair->group;
 
@@ -489,8 +488,7 @@ esp_err_t gdma_stop(gdma_channel_handle_t dma_chan)
     }
     portEXIT_CRITICAL_SAFE(&dma_chan->spinlock);
 
-err:
-    return ret;
+    return ESP_OK;
 }
 
 esp_err_t gdma_append(gdma_channel_handle_t dma_chan)

components/esp_hw_support/dma/gdma_etm.c

@@ -46,6 +46,7 @@ static esp_err_t gdma_del_etm_task(esp_etm_task_t *task)
         gdma_ll_tx_enable_etm_task(group->hal.dev, pair->pair_id, false);
     }
     free(gdma_task);
+    dma_chan->flags.start_stop_by_etm = false;
     return ESP_OK;
 }
 
@@ -105,6 +106,8 @@ esp_err_t gdma_new_etm_task(gdma_channel_handle_t dma_chan, const gdma_etm_task_
     }
     ESP_GOTO_ON_FALSE(task_id != 0, ESP_ERR_NOT_SUPPORTED, err, TAG, "not supported task type");
 
+    // set a flag, now the GDMA channel is start/stop by ETM subsystem
+    dma_chan->flags.start_stop_by_etm = true;
     // fill the ETM task object
     task->chan = dma_chan;
     task->base.task_id = task_id;

components/esp_hw_support/dma/gdma_priv.h

@@ -67,6 +67,9 @@ struct gdma_channel_t {
     size_t sram_alignment;  // alignment for memory in SRAM
     size_t psram_alignment; // alignment for memory in PSRAM
     esp_err_t (*del)(gdma_channel_t *channel); // channel deletion function, it's polymorphic, see `gdma_del_tx_channel` or `gdma_del_rx_channel`
+    struct {
+        uint32_t start_stop_by_etm: 1; // whether the channel is started/stopped by ETM
+    } flags;
 };
 
 struct gdma_tx_channel_t {