mbed official
mbed library sources. Supersedes mbed-src.
Dependents: Nucleo_Hello_Encoder BLE_iBeaconScan AM1805_DEMO DISCO-F429ZI_ExportTemplate1 ... more
Diff: targets/TARGET_NUVOTON/TARGET_NUC472/serial_api.c
- Revision:
- 149:156823d33999
- Parent:
- 144:ef7eb2e8f9f7
- Child:
- 151:5eaa88a5bcc7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_NUVOTON/TARGET_NUC472/serial_api.c Fri Oct 28 11:17:30 2016 +0100
@@ -0,0 +1,1097 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2015-2016 Nuvoton
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "serial_api.h"
+
+#if DEVICE_SERIAL
+
+#include "cmsis.h"
+#include "mbed_error.h"
+#include "mbed_assert.h"
+#include "PeripheralPins.h"
+#include "nu_modutil.h"
+#include "nu_bitutil.h"
+
+#if DEVICE_SERIAL_ASYNCH
+#include "dma_api.h"
+#include "dma.h"
+#endif
+
+struct nu_uart_var {
+ serial_t * obj;
+ uint32_t fifo_size_tx;
+ uint32_t fifo_size_rx;
+ void (*vec)(void);
+#if DEVICE_SERIAL_ASYNCH
+ void (*vec_async)(void);
+ uint8_t pdma_perp_tx;
+ uint8_t pdma_perp_rx;
+#endif
+};
+
+static void uart0_vec(void);
+static void uart1_vec(void);
+static void uart2_vec(void);
+static void uart3_vec(void);
+static void uart4_vec(void);
+static void uart5_vec(void);
+static void uart_irq(serial_t *obj);
+
+#if DEVICE_SERIAL_ASYNCH
+static void uart0_vec_async(void);
+static void uart1_vec_async(void);
+static void uart2_vec_async(void);
+static void uart3_vec_async(void);
+static void uart4_vec_async(void);
+static void uart5_vec_async(void);
+static void uart_irq_async(serial_t *obj);
+
+static void uart_dma_handler_tx(uint32_t id, uint32_t event);
+static void uart_dma_handler_rx(uint32_t id, uint32_t event);
+
+static void serial_tx_enable_interrupt(serial_t *obj, uint32_t address, uint8_t enable);
+static void serial_rx_enable_interrupt(serial_t *obj, uint32_t address, uint8_t enable);
+static int serial_write_async(serial_t *obj);
+static int serial_read_async(serial_t *obj);
+
+static uint32_t serial_rx_event_check(serial_t *obj);
+static uint32_t serial_tx_event_check(serial_t *obj);
+
+static int serial_is_tx_complete(serial_t *obj);
+static void serial_tx_enable_event(serial_t *obj, int event, uint8_t enable);
+
+static void serial_tx_buffer_set(serial_t *obj, const void *tx, size_t length, uint8_t width);
+static void serial_rx_buffer_set(serial_t *obj, void *rx, size_t length, uint8_t width);
+static void serial_rx_set_char_match(serial_t *obj, uint8_t char_match);
+static void serial_rx_enable_event(serial_t *obj, int event, uint8_t enable);
+static int serial_is_rx_complete(serial_t *obj);
+
+static void serial_check_dma_usage(DMAUsage *dma_usage, int *dma_ch);
+static int serial_is_irq_en(serial_t *obj, SerialIrq irq);
+#endif
+
+static struct nu_uart_var uart0_var = {
+ .obj = NULL,
+ .fifo_size_tx = 64,
+ .fifo_size_rx = 64,
+ .vec = uart0_vec,
+#if DEVICE_SERIAL_ASYNCH
+ .vec_async = uart0_vec_async,
+ .pdma_perp_tx = PDMA_UART0_TX,
+ .pdma_perp_rx = PDMA_UART0_RX
+#endif
+};
+static struct nu_uart_var uart1_var = {
+ .obj = NULL,
+ .fifo_size_tx = 16,
+ .fifo_size_rx = 16,
+ .vec = uart1_vec,
+#if DEVICE_SERIAL_ASYNCH
+ .vec_async = uart1_vec_async,
+ .pdma_perp_tx = PDMA_UART1_TX,
+ .pdma_perp_rx = PDMA_UART1_RX
+#endif
+};
+static struct nu_uart_var uart2_var = {
+ .obj = NULL,
+ .fifo_size_tx = 16,
+ .fifo_size_rx = 16,
+ .vec = uart2_vec,
+#if DEVICE_SERIAL_ASYNCH
+ .vec_async = uart2_vec_async,
+ .pdma_perp_tx = PDMA_UART2_TX,
+ .pdma_perp_rx = PDMA_UART2_RX
+#endif
+};
+static struct nu_uart_var uart3_var = {
+ .obj = NULL,
+ .fifo_size_tx = 16,
+ .fifo_size_rx = 16,
+ .vec = uart3_vec,
+#if DEVICE_SERIAL_ASYNCH
+ .vec_async = uart3_vec_async,
+ .pdma_perp_tx = PDMA_UART3_TX,
+ .pdma_perp_rx = PDMA_UART3_RX
+#endif
+};
+static struct nu_uart_var uart4_var = {
+ .obj = NULL,
+ .fifo_size_tx = 16,
+ .fifo_size_rx = 16,
+ .vec = uart4_vec,
+#if DEVICE_SERIAL_ASYNCH
+ .vec_async = uart4_vec_async,
+ .pdma_perp_tx = PDMA_UART4_TX,
+ .pdma_perp_rx = PDMA_UART4_RX
+#endif
+};
+static struct nu_uart_var uart5_var = {
+ .obj = NULL,
+ .fifo_size_tx = 16,
+ .fifo_size_rx = 16,
+ .vec = uart5_vec,
+#if DEVICE_SERIAL_ASYNCH
+ .vec_async = uart5_vec_async,
+ .pdma_perp_tx = PDMA_UART5_TX,
+ .pdma_perp_rx = PDMA_UART5_RX
+#endif
+};
+
+
+int stdio_uart_inited = 0;
+serial_t stdio_uart;
+static uint32_t uart_modinit_mask = 0;
+
+static const struct nu_modinit_s uart_modinit_tab[] = {
+ {UART_0, UART0_MODULE, CLK_CLKSEL1_UARTSEL_HIRC, CLK_CLKDIV0_UART(1), UART0_RST, UART0_IRQn, &uart0_var},
+ {UART_1, UART1_MODULE, CLK_CLKSEL1_UARTSEL_HIRC, CLK_CLKDIV0_UART(1), UART1_RST, UART1_IRQn, &uart1_var},
+ {UART_2, UART2_MODULE, CLK_CLKSEL1_UARTSEL_HIRC, CLK_CLKDIV0_UART(1), UART2_RST, UART2_IRQn, &uart2_var},
+ {UART_3, UART3_MODULE, CLK_CLKSEL1_UARTSEL_HIRC, CLK_CLKDIV0_UART(1), UART3_RST, UART3_IRQn, &uart3_var},
+ {UART_4, UART4_MODULE, CLK_CLKSEL1_UARTSEL_HIRC, CLK_CLKDIV0_UART(1), UART4_RST, UART4_IRQn, &uart4_var},
+ {UART_5, UART5_MODULE, CLK_CLKSEL1_UARTSEL_HIRC, CLK_CLKDIV0_UART(1), UART5_RST, UART5_IRQn, &uart5_var},
+
+ {NC, 0, 0, 0, 0, (IRQn_Type) 0, NULL}
+};
+
+extern void mbed_sdk_init(void);
+
+void serial_init(serial_t *obj, PinName tx, PinName rx)
+{
+ // NOTE: serial_init() gets called from _sys_open() timing of which is before main()/mbed_sdk_init().
+ mbed_sdk_init();
+
+ // Determine which UART_x the pins are used for
+ uint32_t uart_tx = pinmap_peripheral(tx, PinMap_UART_TX);
+ uint32_t uart_rx = pinmap_peripheral(rx, PinMap_UART_RX);
+ // Get the peripheral name (UART_x) from the pins and assign it to the object
+ obj->serial.uart = (UARTName) pinmap_merge(uart_tx, uart_rx);
+ MBED_ASSERT((int)obj->serial.uart != NC);
+
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ // Reset this module
+ SYS_ResetModule(modinit->rsetidx);
+
+ // Select IP clock source
+ CLK_SetModuleClock(modinit->clkidx, modinit->clksrc, modinit->clkdiv);
+ // Enable IP clock
+ CLK_EnableModuleClock(modinit->clkidx);
+
+ pinmap_pinout(tx, PinMap_UART_TX);
+ pinmap_pinout(rx, PinMap_UART_RX);
+ // FIXME: Why PullUp?
+ //if (tx != NC) {
+ // pin_mode(tx, PullUp);
+ //}
+ //if (rx != NC) {
+ // pin_mode(rx, PullUp);
+ //}
+ obj->serial.pin_tx = tx;
+ obj->serial.pin_rx = rx;
+
+ // Configure the UART module and set its baudrate
+ serial_baud(obj, 9600);
+ // Configure data bits, parity, and stop bits
+ serial_format(obj, 8, ParityNone, 1);
+
+ obj->serial.vec = ((struct nu_uart_var *) modinit->var)->vec;
+
+#if DEVICE_SERIAL_ASYNCH
+ obj->serial.dma_usage_tx = DMA_USAGE_NEVER;
+ obj->serial.dma_usage_rx = DMA_USAGE_NEVER;
+ obj->serial.event = 0;
+ obj->serial.dma_chn_id_tx = DMA_ERROR_OUT_OF_CHANNELS;
+ obj->serial.dma_chn_id_rx = DMA_ERROR_OUT_OF_CHANNELS;
+#endif
+
+ // For stdio management
+ if (obj == &stdio_uart) {
+ stdio_uart_inited = 1;
+ /* NOTE: Not required anymore because stdio_uart will be manually initialized in mbed-drivers/source/retarget.cpp from mbed beta */
+ //memcpy(&stdio_uart, obj, sizeof(serial_t));
+ }
+
+ // Mark this module to be inited.
+ int i = modinit - uart_modinit_tab;
+ uart_modinit_mask |= 1 << i;
+}
+
+void serial_free(serial_t *obj)
+{
+#if DEVICE_SERIAL_ASYNCH
+ if (obj->serial.dma_chn_id_tx != DMA_ERROR_OUT_OF_CHANNELS) {
+ dma_channel_free(obj->serial.dma_chn_id_tx);
+ obj->serial.dma_chn_id_tx = DMA_ERROR_OUT_OF_CHANNELS;
+ }
+ if (obj->serial.dma_chn_id_rx != DMA_ERROR_OUT_OF_CHANNELS) {
+ dma_channel_free(obj->serial.dma_chn_id_rx);
+ obj->serial.dma_chn_id_rx = DMA_ERROR_OUT_OF_CHANNELS;
+ }
+#endif
+
+ UART_Close((UART_T *) NU_MODBASE(obj->serial.uart));
+
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ UART_DISABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), (UART_INTEN_RDAIEN_Msk | UART_INTEN_THREIEN_Msk | UART_INTEN_RXTOIEN_Msk));
+ NVIC_DisableIRQ(modinit->irq_n);
+
+ // Disable IP clock
+ CLK_DisableModuleClock(modinit->clkidx);
+
+ ((struct nu_uart_var *) modinit->var)->obj = NULL;
+
+ if (obj == &stdio_uart) {
+ stdio_uart_inited = 0;
+ }
+
+ // Mark this module to be deinited.
+ int i = modinit - uart_modinit_tab;
+ uart_modinit_mask &= ~(1 << i);
+}
+
+void serial_baud(serial_t *obj, int baudrate) {
+ // Flush Tx FIFO. Otherwise, output data may get lost on this change.
+ while (! UART_IS_TX_EMPTY(((UART_T *) obj->serial.uart)));
+
+ obj->serial.baudrate = baudrate;
+ UART_Open((UART_T *) NU_MODBASE(obj->serial.uart), baudrate);
+}
+
+void serial_format(serial_t *obj, int data_bits, SerialParity parity, int stop_bits) {
+ // Flush Tx FIFO. Otherwise, output data may get lost on this change.
+ while (! UART_IS_TX_EMPTY(((UART_T *) obj->serial.uart)));
+
+ // TODO: Assert for not supported parity and data bits
+ obj->serial.databits = data_bits;
+ obj->serial.parity = parity;
+ obj->serial.stopbits = stop_bits;
+
+ uint32_t databits_intern = (data_bits == 5) ? UART_WORD_LEN_5 :
+ (data_bits == 6) ? UART_WORD_LEN_6 :
+ (data_bits == 7) ? UART_WORD_LEN_7 :
+ UART_WORD_LEN_8;
+ uint32_t parity_intern = (parity == ParityOdd || parity == ParityForced1) ? UART_PARITY_ODD :
+ (parity == ParityEven || parity == ParityForced0) ? UART_PARITY_EVEN :
+ UART_PARITY_NONE;
+ uint32_t stopbits_intern = (stop_bits == 2) ? UART_STOP_BIT_2 : UART_STOP_BIT_1;
+ UART_SetLine_Config((UART_T *) NU_MODBASE(obj->serial.uart),
+ 0, // Don't change baudrate
+ databits_intern,
+ parity_intern,
+ stopbits_intern);
+}
+
+#if DEVICE_SERIAL_FC
+
+void serial_set_flow_control(serial_t *obj, FlowControl type, PinName rxflow, PinName txflow)
+{
+ UART_T *uart_base = (UART_T *) NU_MODBASE(obj->serial.uart);
+
+ // First, disable flow control completely.
+ uart_base->INTEN &= ~(UART_INTEN_ATORTSEN_Msk | UART_INTEN_ATOCTSEN_Msk);
+
+ if ((type == FlowControlRTS || type == FlowControlRTSCTS) && rxflow != NC) {
+ // Check if RTS pin matches.
+ uint32_t uart_rts = pinmap_peripheral(rxflow, PinMap_UART_RTS);
+ MBED_ASSERT(uart_rts == obj->serial.uart);
+ // Enable the pin for RTS function
+ pinmap_pinout(rxflow, PinMap_UART_RTS);
+ // nRTS pin output is high level active
+ uart_base->MODEM = (uart_base->MODEM & ~UART_MODEM_RTSACTLV_Msk) | UART_MODEM_RTSACTLV_Msk;
+ uart_base->FIFO = (uart_base->FIFO & ~UART_FIFO_RTSTRGLV_Msk) | UART_FIFO_RTSTRGLV_8BYTES;
+ // Enable RTS
+ uart_base->INTEN |= UART_INTEN_ATORTSEN_Msk;
+ }
+
+ if ((type == FlowControlCTS || type == FlowControlRTSCTS) && txflow != NC) {
+ // Check if CTS pin matches.
+ uint32_t uart_cts = pinmap_peripheral(txflow, PinMap_UART_CTS);
+ MBED_ASSERT(uart_cts == obj->serial.uart);
+ // Enable the pin for CTS function
+ pinmap_pinout(txflow, PinMap_UART_CTS);
+ // nCTS pin input is high level active
+ uart_base->MODEMSTS = (uart_base->MODEMSTS & ~UART_MODEMSTS_CTSACTLV_Msk) | UART_MODEMSTS_CTSACTLV_Msk;
+ // Enable CTS
+ uart_base->INTEN |= UART_INTEN_ATOCTSEN_Msk;
+ }
+}
+
+#endif //DEVICE_SERIAL_FC
+
+void serial_irq_handler(serial_t *obj, uart_irq_handler handler, uint32_t id)
+{
+ // Flush Tx FIFO. Otherwise, output data may get lost on this change.
+ while (! UART_IS_TX_EMPTY(((UART_T *) obj->serial.uart)));
+
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ ((struct nu_uart_var *) modinit->var)->obj = obj;
+ obj->serial.irq_handler = (uint32_t) handler;
+ obj->serial.irq_id = id;
+
+ // Restore sync-mode vector
+ obj->serial.vec = ((struct nu_uart_var *) modinit->var)->vec;
+}
+
+void serial_irq_set(serial_t *obj, SerialIrq irq, uint32_t enable)
+{
+ if (enable) {
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ NVIC_SetVector(modinit->irq_n, (uint32_t) obj->serial.vec);
+ NVIC_EnableIRQ(modinit->irq_n);
+
+ switch (irq) {
+ // NOTE: Setting inten_msk first to avoid race condition
+ case RxIrq:
+ obj->serial.inten_msk = obj->serial.inten_msk | (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk);
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk));
+ break;
+ case TxIrq:
+ obj->serial.inten_msk = obj->serial.inten_msk | UART_INTEN_THREIEN_Msk;
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_THREIEN_Msk);
+ break;
+ }
+ } else { // disable
+ switch (irq) {
+ case RxIrq:
+ UART_DISABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk));
+ obj->serial.inten_msk = obj->serial.inten_msk & ~(UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk);
+ break;
+ case TxIrq:
+ UART_DISABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_THREIEN_Msk);
+ obj->serial.inten_msk = obj->serial.inten_msk & ~UART_INTEN_THREIEN_Msk;
+ break;
+ }
+ }
+}
+
+int serial_getc(serial_t *obj)
+{
+ // TODO: Fix every byte access requires accompaniness of one interrupt. This degrades performance much.
+ while (! serial_readable(obj));
+ int c = UART_READ(((UART_T *) NU_MODBASE(obj->serial.uart)));
+
+ // Simulate clear of the interrupt flag
+ if (obj->serial.inten_msk & (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk)) {
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk));
+ }
+
+ return c;
+}
+
+void serial_putc(serial_t *obj, int c)
+{
+ // TODO: Fix every byte access requires accompaniness of one interrupt. This degrades performance much.
+ while (! serial_writable(obj));
+ UART_WRITE(((UART_T *) NU_MODBASE(obj->serial.uart)), c);
+
+ // Simulate clear of the interrupt flag
+ if (obj->serial.inten_msk & UART_INTEN_THREIEN_Msk) {
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_THREIEN_Msk);
+ }
+}
+
+int serial_readable(serial_t *obj)
+{
+ //return UART_IS_RX_READY(((UART_T *) NU_MODBASE(obj->serial.uart)));
+ return ! (((UART_T *) NU_MODBASE(obj->serial.uart))->FIFOSTS & UART_FIFOSTS_RXEMPTY_Msk);
+}
+
+int serial_writable(serial_t *obj)
+{
+ return ! UART_IS_TX_FULL(((UART_T *) NU_MODBASE(obj->serial.uart)));
+}
+
+void serial_pinout_tx(PinName tx)
+{
+ pinmap_pinout(tx, PinMap_UART_TX);
+}
+
+void serial_break_set(serial_t *obj)
+{
+ ((UART_T *) NU_MODBASE(obj->serial.uart))->LINE |= UART_LINE_BCB_Msk;
+}
+
+void serial_break_clear(serial_t *obj)
+{
+ ((UART_T *) NU_MODBASE(obj->serial.uart))->LINE &= ~UART_LINE_BCB_Msk;
+}
+
+static void uart0_vec(void)
+{
+ uart_irq(uart0_var.obj);
+}
+
+static void uart1_vec(void)
+{
+ uart_irq(uart1_var.obj);
+}
+
+static void uart2_vec(void)
+{
+ uart_irq(uart2_var.obj);
+}
+
+static void uart3_vec(void)
+{
+ uart_irq(uart3_var.obj);
+}
+
+static void uart4_vec(void)
+{
+ uart_irq(uart4_var.obj);
+}
+
+static void uart5_vec(void)
+{
+ uart_irq(uart5_var.obj);
+}
+
+static void uart_irq(serial_t *obj)
+{
+ UART_T *uart_base = (UART_T *) NU_MODBASE(obj->serial.uart);
+
+ if (uart_base->INTSTS & (UART_INTSTS_RDAINT_Msk | UART_INTSTS_RXTOINT_Msk)) {
+ // Simulate clear of the interrupt flag. Temporarily disable the interrupt here and to be recovered on next read.
+ UART_DISABLE_INT(uart_base, (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk));
+ if (obj->serial.irq_handler) {
+ ((uart_irq_handler) obj->serial.irq_handler)(obj->serial.irq_id, RxIrq);
+ }
+ }
+
+ if (uart_base->INTSTS & UART_INTSTS_THREINT_Msk) {
+ // Simulate clear of the interrupt flag. Temporarily disable the interrupt here and to be recovered on next write.
+ UART_DISABLE_INT(uart_base, UART_INTEN_THREIEN_Msk);
+ if (obj->serial.irq_handler) {
+ ((uart_irq_handler) obj->serial.irq_handler)(obj->serial.irq_id, TxIrq);
+ }
+ }
+
+ // FIXME: Ignore all other interrupt flags. Clear them. Otherwise, program will get stuck in interrupt.
+ uart_base->INTSTS = uart_base->INTSTS;
+ uart_base->FIFOSTS = uart_base->FIFOSTS;
+}
+
+
+#if DEVICE_SERIAL_ASYNCH
+int serial_tx_asynch(serial_t *obj, const void *tx, size_t tx_length, uint8_t tx_width, uint32_t handler, uint32_t event, DMAUsage hint)
+{
+ // NOTE: tx_width is deprecated. Assume its value is databits ceiled to the nearest number among 8, 16, and 32.
+ tx_width = (obj->serial.databits <= 8) ? 8 : (obj->serial.databits <= 16) ? 16 : 32;
+
+ MBED_ASSERT(tx_width == 8 || tx_width == 16 || tx_width == 32);
+
+ obj->serial.dma_usage_tx = hint;
+ serial_check_dma_usage(&obj->serial.dma_usage_tx, &obj->serial.dma_chn_id_tx);
+
+ // UART IRQ is necessary for both interrupt way and DMA way
+ serial_tx_enable_event(obj, event, 1);
+ serial_tx_buffer_set(obj, tx, tx_length, tx_width);
+ //UART_HAL_DisableTransmitter(obj->serial.address);
+ //UART_HAL_FlushTxFifo(obj->serial.address);
+ //UART_HAL_EnableTransmitter(obj->serial.address);
+
+ int n_word = 0;
+ if (obj->serial.dma_usage_tx == DMA_USAGE_NEVER) {
+ // Interrupt way
+ n_word = serial_write_async(obj);
+ serial_tx_enable_interrupt(obj, handler, 1);
+ } else {
+ // DMA way
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ PDMA->CHCTL |= 1 << obj->serial.dma_chn_id_tx; // Enable this DMA channel
+ PDMA_SetTransferMode(obj->serial.dma_chn_id_tx,
+ ((struct nu_uart_var *) modinit->var)->pdma_perp_tx, // Peripheral connected to this PDMA
+ 0, // Scatter-gather disabled
+ 0); // Scatter-gather descriptor address
+ PDMA_SetTransferCnt(obj->serial.dma_chn_id_tx,
+ (tx_width == 8) ? PDMA_WIDTH_8 : (tx_width == 16) ? PDMA_WIDTH_16 : PDMA_WIDTH_32,
+ tx_length);
+ PDMA_SetTransferAddr(obj->serial.dma_chn_id_tx,
+ ((uint32_t) tx) + (tx_width / 8) * tx_length, // NOTE: End of source address
+ PDMA_SAR_INC, // Source address incremental
+ (uint32_t) obj->serial.uart, // Destination address
+ PDMA_DAR_FIX); // Destination address fixed
+ PDMA_SetBurstType(obj->serial.dma_chn_id_tx,
+ PDMA_REQ_SINGLE, // Single mode
+ 0); // Burst size
+ PDMA_EnableInt(obj->serial.dma_chn_id_tx,
+ 0); // Interrupt type. No use here
+ // Register DMA event handler
+ dma_set_handler(obj->serial.dma_chn_id_tx, (uint32_t) uart_dma_handler_tx, (uint32_t) obj, DMA_EVENT_ALL);
+ serial_tx_enable_interrupt(obj, handler, 1);
+ ((UART_T *) NU_MODBASE(obj->serial.uart))->INTEN |= UART_INTEN_TXPDMAEN_Msk; // Start DMA transfer
+ }
+
+ return n_word;
+}
+
+void serial_rx_asynch(serial_t *obj, void *rx, size_t rx_length, uint8_t rx_width, uint32_t handler, uint32_t event, uint8_t char_match, DMAUsage hint)
+{
+ // NOTE: rx_width is deprecated. Assume its value is databits ceiled to the nearest number among 8, 16, and 32.
+ rx_width = (obj->serial.databits <= 8) ? 8 : (obj->serial.databits <= 16) ? 16 : 32;
+
+ MBED_ASSERT(rx_width == 8 || rx_width == 16 || rx_width == 32);
+
+ obj->serial.dma_usage_rx = hint;
+ serial_check_dma_usage(&obj->serial.dma_usage_rx, &obj->serial.dma_chn_id_rx);
+ // DMA doesn't support char match, so fall back to IRQ if it is requested.
+ if (obj->serial.dma_usage_rx != DMA_USAGE_NEVER &&
+ (event & SERIAL_EVENT_RX_CHARACTER_MATCH) &&
+ char_match != SERIAL_RESERVED_CHAR_MATCH) {
+ obj->serial.dma_usage_rx = DMA_USAGE_NEVER;
+ dma_channel_free(obj->serial.dma_chn_id_rx);
+ obj->serial.dma_chn_id_rx = DMA_ERROR_OUT_OF_CHANNELS;
+ }
+
+ // UART IRQ is necessary for both interrupt way and DMA way
+ serial_rx_enable_event(obj, event, 1);
+ serial_rx_buffer_set(obj, rx, rx_length, rx_width);
+ serial_rx_set_char_match(obj, char_match);
+ //UART_HAL_DisableReceiver(obj->serial.address);
+ //UART_HAL_FlushRxFifo(obj->serial.address);
+ //UART_HAL_EnableReceiver(obj->serial.address);
+
+ if (obj->serial.dma_usage_rx == DMA_USAGE_NEVER) {
+ // Interrupt way
+ serial_rx_enable_interrupt(obj, handler, 1);
+ } else {
+ // DMA way
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ PDMA->CHCTL |= 1 << obj->serial.dma_chn_id_rx; // Enable this DMA channel
+ PDMA_SetTransferMode(obj->serial.dma_chn_id_rx,
+ ((struct nu_uart_var *) modinit->var)->pdma_perp_rx, // Peripheral connected to this PDMA
+ 0, // Scatter-gather disabled
+ 0); // Scatter-gather descriptor address
+ PDMA_SetTransferCnt(obj->serial.dma_chn_id_rx,
+ (rx_width == 8) ? PDMA_WIDTH_8 : (rx_width == 16) ? PDMA_WIDTH_16 : PDMA_WIDTH_32,
+ rx_length);
+ PDMA_SetTransferAddr(obj->serial.dma_chn_id_rx,
+ (uint32_t) obj->serial.uart, // Source address
+ PDMA_SAR_FIX, // Source address fixed
+ ((uint32_t) rx) + (rx_width / 8) * rx_length, // NOTE: End of destination address
+ PDMA_DAR_INC); // Destination address incremental
+ PDMA_SetBurstType(obj->serial.dma_chn_id_rx,
+ PDMA_REQ_SINGLE, // Single mode
+ 0); // Burst size
+ PDMA_EnableInt(obj->serial.dma_chn_id_rx,
+ 0); // Interrupt type. No use here
+ // Register DMA event handler
+ dma_set_handler(obj->serial.dma_chn_id_rx, (uint32_t) uart_dma_handler_rx, (uint32_t) obj, DMA_EVENT_ALL);
+ serial_rx_enable_interrupt(obj, handler, 1);
+ ((UART_T *) NU_MODBASE(obj->serial.uart))->INTEN |= UART_INTEN_RXPDMAEN_Msk; // Start DMA transfer
+ }
+}
+
+void serial_tx_abort_asynch(serial_t *obj)
+{
+ // Flush Tx FIFO. Otherwise, output data may get lost on this change.
+ while (! UART_IS_TX_EMPTY(((UART_T *) obj->serial.uart)));
+
+ if (obj->serial.dma_usage_tx != DMA_USAGE_NEVER) {
+ if (obj->serial.dma_chn_id_tx != DMA_ERROR_OUT_OF_CHANNELS) {
+ PDMA_DisableInt(obj->serial.dma_chn_id_tx, 0);
+ // FIXME: Next PDMA transfer will fail with PDMA_STOP() called. Cause is unknown.
+ //PDMA_STOP(obj->serial.dma_chn_id_tx);
+ PDMA->CHCTL &= ~(1 << obj->serial.dma_chn_id_tx);
+ }
+ UART_DISABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_TXPDMAEN_Msk);
+ }
+
+ // Necessary for both interrupt way and DMA way
+ serial_irq_set(obj, TxIrq, 0);
+ // FIXME: more complete abort operation
+ //UART_HAL_DisableTransmitter(obj->serial.serial.address);
+ //UART_HAL_FlushTxFifo(obj->serial.serial.address);
+}
+
+void serial_rx_abort_asynch(serial_t *obj)
+{
+ if (obj->serial.dma_usage_rx != DMA_USAGE_NEVER) {
+ if (obj->serial.dma_chn_id_rx != DMA_ERROR_OUT_OF_CHANNELS) {
+ PDMA_DisableInt(obj->serial.dma_chn_id_rx, 0);
+ // FIXME: Next PDMA transfer will fail with PDMA_STOP() called. Cause is unknown.
+ //PDMA_STOP(obj->serial.dma_chn_id_rx);
+ PDMA->CHCTL &= ~(1 << obj->serial.dma_chn_id_rx);
+ }
+ UART_DISABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_RXPDMAEN_Msk);
+ }
+
+ // Necessary for both interrupt way and DMA way
+ serial_irq_set(obj, RxIrq, 0);
+ // FIXME: more complete abort operation
+ //UART_HAL_DisableReceiver(obj->serial.serial.address);
+ //UART_HAL_FlushRxFifo(obj->serial.serial.address);
+}
+
+uint8_t serial_tx_active(serial_t *obj)
+{
+ return serial_is_irq_en(obj, TxIrq);
+}
+
+uint8_t serial_rx_active(serial_t *obj)
+{
+ return serial_is_irq_en(obj, RxIrq);
+}
+
+int serial_irq_handler_asynch(serial_t *obj)
+{
+ int event_rx = 0;
+ int event_tx = 0;
+
+ // Necessary for both interrup way and DMA way
+ if (serial_is_irq_en(obj, RxIrq)) {
+ event_rx = serial_rx_event_check(obj);
+ if (event_rx) {
+ serial_rx_abort_asynch(obj);
+ }
+ }
+
+ if (serial_is_irq_en(obj, TxIrq)) {
+ event_tx = serial_tx_event_check(obj);
+ if (event_tx) {
+ serial_tx_abort_asynch(obj);
+ }
+ }
+
+ return (obj->serial.event & (event_rx | event_tx));
+}
+
+int serial_allow_powerdown(void)
+{
+ uint32_t modinit_mask = uart_modinit_mask;
+ while (modinit_mask) {
+ int uart_idx = nu_ctz(modinit_mask);
+ const struct nu_modinit_s *modinit = uart_modinit_tab + uart_idx;
+ if (modinit->modname != NC) {
+ UART_T *uart_base = (UART_T *) NU_MODBASE(modinit->modname);
+ // Disallow entering power-down mode if Tx FIFO has data to flush
+ if (! UART_IS_TX_EMPTY((uart_base))) {
+ return 0;
+ }
+ // Disallow entering power-down mode if async Rx transfer (not PDMA) is on-going
+ if (uart_base->INTEN & (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk)) {
+ return 0;
+ }
+ // Disallow entering power-down mode if async Rx transfer (PDMA) is on-going
+ if (uart_base->INTEN & UART_INTEN_RXPDMAEN_Msk) {
+ return 0;
+ }
+ }
+ modinit_mask &= ~(1 << uart_idx);
+ }
+
+ return 1;
+}
+
+static void uart0_vec_async(void)
+{
+ uart_irq_async(uart0_var.obj);
+}
+
+static void uart1_vec_async(void)
+{
+ uart_irq_async(uart1_var.obj);
+}
+
+static void uart2_vec_async(void)
+{
+ uart_irq_async(uart2_var.obj);
+}
+
+static void uart3_vec_async(void)
+{
+ uart_irq_async(uart3_var.obj);
+}
+
+static void uart4_vec_async(void)
+{
+ uart_irq_async(uart4_var.obj);
+}
+
+static void uart5_vec_async(void)
+{
+ uart_irq_async(uart5_var.obj);
+}
+
+static void uart_irq_async(serial_t *obj)
+{
+ if (serial_is_irq_en(obj, RxIrq)) {
+ (*obj->serial.irq_handler_rx_async)();
+ }
+ if (serial_is_irq_en(obj, TxIrq)) {
+ (*obj->serial.irq_handler_tx_async)();
+ }
+}
+
+static void serial_rx_set_char_match(serial_t *obj, uint8_t char_match)
+{
+ obj->char_match = char_match;
+ obj->char_found = 0;
+}
+
+static void serial_tx_enable_event(serial_t *obj, int event, uint8_t enable)
+{
+ obj->serial.event &= ~SERIAL_EVENT_TX_MASK;
+ obj->serial.event |= (event & SERIAL_EVENT_TX_MASK);
+
+ //if (event & SERIAL_EVENT_TX_COMPLETE) {
+ //}
+}
+
+static void serial_rx_enable_event(serial_t *obj, int event, uint8_t enable)
+{
+ obj->serial.event &= ~SERIAL_EVENT_RX_MASK;
+ obj->serial.event |= (event & SERIAL_EVENT_RX_MASK);
+
+ //if (event & SERIAL_EVENT_RX_COMPLETE) {
+ //}
+ //if (event & SERIAL_EVENT_RX_OVERRUN_ERROR) {
+ //}
+ if (event & SERIAL_EVENT_RX_FRAMING_ERROR) {
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_RLSIEN_Msk);
+ }
+ if (event & SERIAL_EVENT_RX_PARITY_ERROR) {
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_RLSIEN_Msk);
+ }
+ if (event & SERIAL_EVENT_RX_OVERFLOW) {
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_BUFERRIEN_Msk);
+ }
+ //if (event & SERIAL_EVENT_RX_CHARACTER_MATCH) {
+ //}
+}
+
+static int serial_is_tx_complete(serial_t *obj)
+{
+ // NOTE: Exclude tx fifo empty check due to no such interrupt on DMA way
+ //return (obj->tx_buff.pos == obj->tx_buff.length) && UART_GET_TX_EMPTY(((UART_T *) NU_MODBASE(obj->serial.uart)));
+ // FIXME: Premature abort???
+ return (obj->tx_buff.pos == obj->tx_buff.length);
+}
+
+static int serial_is_rx_complete(serial_t *obj)
+{
+ //return (obj->rx_buff.pos == obj->rx_buff.length) && UART_GET_RX_EMPTY(((UART_T *) NU_MODBASE(obj->serial.uart)));
+ return (obj->rx_buff.pos == obj->rx_buff.length);
+}
+
+static uint32_t serial_tx_event_check(serial_t *obj)
+{
+ UART_T *uart_base = (UART_T *) NU_MODBASE(obj->serial.uart);
+
+ if (uart_base->INTSTS & UART_INTSTS_THREINT_Msk) {
+ // Simulate clear of the interrupt flag. Temporarily disable the interrupt here and to be recovered on next write.
+ UART_DISABLE_INT(uart_base, UART_INTEN_THREIEN_Msk);
+ }
+
+ uint32_t event = 0;
+
+ if (obj->serial.dma_usage_tx == DMA_USAGE_NEVER) {
+ serial_write_async(obj);
+ }
+
+ if (serial_is_tx_complete(obj)) {
+ event |= SERIAL_EVENT_TX_COMPLETE;
+ }
+
+ return event;
+}
+
+static uint32_t serial_rx_event_check(serial_t *obj)
+{
+ UART_T *uart_base = (UART_T *) NU_MODBASE(obj->serial.uart);
+
+ if (uart_base->INTSTS & (UART_INTSTS_RDAINT_Msk | UART_INTSTS_RXTOINT_Msk)) {
+ // Simulate clear of the interrupt flag. Temporarily disable the interrupt here and to be recovered on next read.
+ UART_DISABLE_INT(uart_base, (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk));
+ }
+
+ uint32_t event = 0;
+
+ if (uart_base->FIFOSTS & UART_FIFOSTS_BIF_Msk) {
+ uart_base->FIFOSTS = UART_FIFOSTS_BIF_Msk;
+ }
+ if (uart_base->FIFOSTS & UART_FIFOSTS_FEF_Msk) {
+ uart_base->FIFOSTS = UART_FIFOSTS_FEF_Msk;
+ event |= SERIAL_EVENT_RX_FRAMING_ERROR;
+ }
+ if (uart_base->FIFOSTS & UART_FIFOSTS_PEF_Msk) {
+ uart_base->FIFOSTS = UART_FIFOSTS_PEF_Msk;
+ event |= SERIAL_EVENT_RX_PARITY_ERROR;
+ }
+
+ if (uart_base->FIFOSTS & UART_FIFOSTS_RXOVIF_Msk) {
+ uart_base->FIFOSTS = UART_FIFOSTS_RXOVIF_Msk;
+ event |= SERIAL_EVENT_RX_OVERFLOW;
+ }
+
+ if (obj->serial.dma_usage_rx == DMA_USAGE_NEVER) {
+ serial_read_async(obj);
+ }
+
+ if (serial_is_rx_complete(obj)) {
+ event |= SERIAL_EVENT_RX_COMPLETE;
+ }
+ if ((obj->char_match != SERIAL_RESERVED_CHAR_MATCH) && obj->char_found) {
+ event |= SERIAL_EVENT_RX_CHARACTER_MATCH;
+ // FIXME: Timing to reset char_found?
+ //obj->char_found = 0;
+ }
+
+ return event;
+}
+
+static void uart_dma_handler_tx(uint32_t id, uint32_t event_dma)
+{
+ serial_t *obj = (serial_t *) id;
+
+ // FIXME: Pass this error to caller
+ if (event_dma & DMA_EVENT_ABORT) {
+ }
+ // Expect UART IRQ will catch this transfer done event
+ if (event_dma & DMA_EVENT_TRANSFER_DONE) {
+ obj->tx_buff.pos = obj->tx_buff.length;
+ }
+ // FIXME: Pass this error to caller
+ if (event_dma & DMA_EVENT_TIMEOUT) {
+ }
+
+ uart_irq_async(obj);
+}
+
+static void uart_dma_handler_rx(uint32_t id, uint32_t event_dma)
+{
+ serial_t *obj = (serial_t *) id;
+
+ // FIXME: Pass this error to caller
+ if (event_dma & DMA_EVENT_ABORT) {
+ }
+ // Expect UART IRQ will catch this transfer done event
+ if (event_dma & DMA_EVENT_TRANSFER_DONE) {
+ obj->rx_buff.pos = obj->rx_buff.length;
+ }
+ // FIXME: Pass this error to caller
+ if (event_dma & DMA_EVENT_TIMEOUT) {
+ }
+
+ uart_irq_async(obj);
+}
+
+static int serial_write_async(serial_t *obj)
+{
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ UART_T *uart_base = (UART_T *) NU_MODBASE(obj->serial.uart);
+
+ uint32_t tx_fifo_max = ((struct nu_uart_var *) modinit->var)->fifo_size_tx;
+ uint32_t tx_fifo_busy = (uart_base->FIFOSTS & UART_FIFOSTS_TXPTR_Msk) >> UART_FIFOSTS_TXPTR_Pos;
+ if (uart_base->FIFOSTS & UART_FIFOSTS_TXFULL_Msk) {
+ tx_fifo_busy = tx_fifo_max;
+ }
+ uint32_t tx_fifo_free = tx_fifo_max - tx_fifo_busy;
+ if (tx_fifo_free == 0) {
+ // Simulate clear of the interrupt flag
+ if (obj->serial.inten_msk & UART_INTEN_THREIEN_Msk) {
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_THREIEN_Msk);
+ }
+ return 0;
+ }
+
+ uint32_t bytes_per_word = obj->tx_buff.width / 8;
+
+ uint8_t *tx = (uint8_t *)(obj->tx_buff.buffer) + bytes_per_word * obj->tx_buff.pos;
+ int n_words = 0;
+ while (obj->tx_buff.pos < obj->tx_buff.length && tx_fifo_free >= bytes_per_word) {
+ switch (bytes_per_word) {
+ case 4:
+ UART_WRITE(((UART_T *) NU_MODBASE(obj->serial.uart)), *tx ++);
+ UART_WRITE(((UART_T *) NU_MODBASE(obj->serial.uart)), *tx ++);
+ case 2:
+ UART_WRITE(((UART_T *) NU_MODBASE(obj->serial.uart)), *tx ++);
+ case 1:
+ UART_WRITE(((UART_T *) NU_MODBASE(obj->serial.uart)), *tx ++);
+ }
+
+ n_words ++;
+ tx_fifo_free -= bytes_per_word;
+ obj->tx_buff.pos ++;
+ }
+
+ if (n_words) {
+ // Simulate clear of the interrupt flag
+ if (obj->serial.inten_msk & UART_INTEN_THREIEN_Msk) {
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), UART_INTEN_THREIEN_Msk);
+ }
+ }
+
+ return n_words;
+}
+
+static int serial_read_async(serial_t *obj)
+{
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ uint32_t rx_fifo_busy = (((UART_T *) NU_MODBASE(obj->serial.uart))->FIFOSTS & UART_FIFOSTS_RXPTR_Msk) >> UART_FIFOSTS_RXPTR_Pos;
+ //uint32_t rx_fifo_free = ((struct nu_uart_var *) modinit->var)->fifo_size_rx - rx_fifo_busy;
+ //if (rx_fifo_free == 0) {
+ // return 0;
+ //}
+
+ uint32_t bytes_per_word = obj->rx_buff.width / 8;
+
+ uint8_t *rx = (uint8_t *)(obj->rx_buff.buffer) + bytes_per_word * obj->rx_buff.pos;
+ int n_words = 0;
+ while (obj->rx_buff.pos < obj->rx_buff.length && rx_fifo_busy >= bytes_per_word) {
+ switch (bytes_per_word) {
+ case 4:
+ *rx ++ = UART_READ(((UART_T *) NU_MODBASE(obj->serial.uart)));
+ *rx ++ = UART_READ(((UART_T *) NU_MODBASE(obj->serial.uart)));
+ case 2:
+ *rx ++ = UART_READ(((UART_T *) NU_MODBASE(obj->serial.uart)));
+ case 1:
+ *rx ++ = UART_READ(((UART_T *) NU_MODBASE(obj->serial.uart)));
+ }
+
+ n_words ++;
+ rx_fifo_busy -= bytes_per_word;
+ obj->rx_buff.pos ++;
+
+ if ((obj->serial.event & SERIAL_EVENT_RX_CHARACTER_MATCH) &&
+ obj->char_match != SERIAL_RESERVED_CHAR_MATCH) {
+ uint8_t *rx_cmp = rx;
+ switch (bytes_per_word) {
+ case 4:
+ rx_cmp -= 2;
+ case 2:
+ rx_cmp --;
+ case 1:
+ rx_cmp --;
+ }
+ if (*rx_cmp == obj->char_match) {
+ obj->char_found = 1;
+ break;
+ }
+ }
+ }
+
+ if (n_words) {
+ // Simulate clear of the interrupt flag
+ if (obj->serial.inten_msk & (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk)) {
+ UART_ENABLE_INT(((UART_T *) NU_MODBASE(obj->serial.uart)), (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk));
+ }
+ }
+
+ return n_words;
+}
+
+static void serial_tx_buffer_set(serial_t *obj, const void *tx, size_t length, uint8_t width)
+{
+ obj->tx_buff.buffer = (void *) tx;
+ obj->tx_buff.length = length;
+ obj->tx_buff.pos = 0;
+ obj->tx_buff.width = width;
+}
+
+static void serial_rx_buffer_set(serial_t *obj, void *rx, size_t length, uint8_t width)
+{
+ obj->rx_buff.buffer = rx;
+ obj->rx_buff.length = length;
+ obj->rx_buff.pos = 0;
+ obj->rx_buff.width = width;
+}
+
+static void serial_tx_enable_interrupt(serial_t *obj, uint32_t handler, uint8_t enable)
+{
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ // Necessary for both interrupt way and DMA way
+ ((struct nu_uart_var *) modinit->var)->obj = obj;
+ // With our own async vector, tx/rx handlers can be different.
+ obj->serial.vec = ((struct nu_uart_var *) modinit->var)->vec_async;
+ obj->serial.irq_handler_tx_async = (void (*)(void)) handler;
+ serial_irq_set(obj, TxIrq, enable);
+}
+
+static void serial_rx_enable_interrupt(serial_t *obj, uint32_t handler, uint8_t enable)
+{
+ const struct nu_modinit_s *modinit = get_modinit(obj->serial.uart, uart_modinit_tab);
+ MBED_ASSERT(modinit != NULL);
+ MBED_ASSERT(modinit->modname == obj->serial.uart);
+
+ // Necessary for both interrupt way and DMA way
+ ((struct nu_uart_var *) modinit->var)->obj = obj;
+ // With our own async vector, tx/rx handlers can be different.
+ obj->serial.vec = ((struct nu_uart_var *) modinit->var)->vec_async;
+ obj->serial.irq_handler_rx_async = (void (*) (void)) handler;
+ serial_irq_set(obj, RxIrq, enable);
+}
+
+static void serial_check_dma_usage(DMAUsage *dma_usage, int *dma_ch)
+{
+ if (*dma_usage != DMA_USAGE_NEVER) {
+ if (*dma_ch == DMA_ERROR_OUT_OF_CHANNELS) {
+ *dma_ch = dma_channel_allocate(DMA_CAP_NONE);
+ }
+ if (*dma_ch == DMA_ERROR_OUT_OF_CHANNELS) {
+ *dma_usage = DMA_USAGE_NEVER;
+ }
+ }
+ else {
+ dma_channel_free(*dma_ch);
+ *dma_ch = DMA_ERROR_OUT_OF_CHANNELS;
+ }
+}
+
+static int serial_is_irq_en(serial_t *obj, SerialIrq irq)
+{
+ int inten_msk = 0;
+
+ switch (irq) {
+ case RxIrq:
+ inten_msk = obj->serial.inten_msk & (UART_INTEN_RDAIEN_Msk | UART_INTEN_RXTOIEN_Msk);
+ break;
+ case TxIrq:
+ inten_msk = obj->serial.inten_msk & UART_INTEN_THREIEN_Msk;
+ break;
+ }
+
+ return !! inten_msk;
+}
+
+#endif // #if DEVICE_SERIAL_ASYNCH
+#endif // #if DEVICE_SERIAL
