- 你好，想问下看到ESP32 UART是支持DMA的，而且例程的readme中写着支持ESP32的，但是为什么cmakelist中条件语句禁止了修改target到ESP32呢，谢谢
测试代码
- dma_descriptor_t *tx_desc; ///< DMA descriptors
- static gdma_channel_handle_t tx_channel;
- uint8_t *tx_dma_buf; //dma buffer
- uhci_seper_chr_t seper_char ={
- .sub_chr_en =0,
- };
- static inline void muhci_ll_init(uhci_dev_t *hw)
- {
- // typeof(hw->conf0) conf0_reg;
- hw->conf0.clk_en = 1;
- hw->conf0.val = 0;
- hw->conf0.clk_en = 1;
- //hw->conf0.val = conf0_reg.val;
- hw->conf0.tx_rst = 1;
- hw->conf0.tx_rst = 0;
- hw->conf0.rx_rst = 1;
- hw->conf0.rx_rst = 0;
- hw->conf1.val = 0;
- }
- esp_err_t uart_gdma_init(void)
- {
- esp_err_t ret;
- int rx_ch_id = 0;
- gdma_channel_alloc_config_t channel_config_tx = {
- .direction = GDMA_CHANNEL_DIRECTION_TX,
- };
- ret = gdma_new_channel(&channel_config_tx, &tx_channel);
- if (ret != ESP_OK) {
- goto err;
- }
- gdma_strategy_config_t strategy_config = {
- .auto_update_desc = true,
- .owner_check = true
- };
- gdma_apply_strategy(tx_channel, &strategy_config);
- gdma_connect(tx_channel, GDMA_MAKE_TRIGGER(GDMA_TRIG_PERIPH_UART, 0));// trig_periph.instance_id ==2
- tx_dma_buf = heap_caps_calloc(1, 2048, MALLOC_CAP_INTERNAL | MALLOC_CAP_DMA);
- if (!tx_dma_buf) {
- ret = ESP_ERR_NO_MEM;
- goto err;
- }
- //malloc dma descriptor
- tx_desc = heap_caps_calloc(1, (sizeof(dma_descriptor_t)), MALLOC_CAP_DMA);
- if (!tx_desc) {
- ret = ESP_ERR_NO_MEM;
- goto err;
- }
- tx_desc->dw0.size = 2048;
- tx_desc->dw0.length = 0;
- tx_desc->dw0.suc_eof = 1;
- tx_desc->dw0.owner = 1;
- tx_desc->buffer = tx_dma_buf;
- tx_desc->next = NULL;
- gdma_get_channel_id(tx_channel, &rx_ch_id);
- ESP_LOGE(TAG, "acquire DMA channel, rx_ch_id=%d", rx_ch_id);
- gdma_ll_tx_reset_channel(&GDMA, rx_ch_id);
- muhci_ll_init(UHCI_LL_GET_HW(0));
- uhci_ll_attach_uart_port(UHCI_LL_GET_HW(0),2);
- uhci_ll_set_seper_chr(UHCI_LL_GET_HW(0), &seper_char);
- return ESP_OK;
- err:
- ESP_LOGE(TAG, "Failed to acquire DMA channel, Err=%d", ret);
- tx_channel = NULL;
- free(tx_dma_buf);
- free(tx_desc);
- return ret;
- }
- void uart_gdma_write(dma_descriptor_t *desc,uint32_t len1)
- {
- desc->dw0.length = len1;
- gdma_start( tx_channel, (intptr_t )desc);
- }
- uart_gdma_init();
- const char *source_str = "testtest\r\n";
- strcpy((char *)tx_dma_buf, source_str);
- uart_gdma_write(tx_desc,10);
uart_gdma: acquire DMA channel, rx_ch_id=0