Diff: source/hic_hal/maxim/max32620/uart.c

Revision:

0:01f31e923fe2

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/source/hic_hal/maxim/max32620/uart.c	Tue Apr 07 12:55:42 2020 +0200
@@ -0,0 +1,316 @@
+/* CMSIS-DAP Interface Firmware
+ * Copyright (c) 2009-2013 ARM Limited
+ *
+ * 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 <string.h>
+#include "max32620.h"
+#include "clkman_regs.h"
+#include "ioman_regs.h"
+#include "gpio_regs.h"
+#include "uart_regs.h"
+#include "uart.h"
+
+// Size must be 2^n
+#define BUFFER_SIZE	(4096)
+
+#define UART_ERRORS (MXC_F_UART_INTFL_RX_FRAMING_ERR | \
+                     MXC_F_UART_INTFL_RX_PARITY_ERR | \
+                     MXC_F_UART_INTFL_RX_FIFO_OVERFLOW)
+
+
+// Track bit rate to avoid calculation from bus clock, clock scaler and baud divisor values
+static uint32_t baudrate;
+
+static mxc_uart_regs_t *CdcAcmUart = MXC_UART0;
+static mxc_uart_fifo_regs_t *CdcAcmUartFifo = MXC_UART0_FIFO;
+static const IRQn_Type CdcAcmUartIrqNumber = UART0_IRQn;
+
+
+static struct {
+    uint8_t  data[BUFFER_SIZE];
+    volatile uint16_t idx_in;
+    volatile uint16_t idx_out;
+    volatile  int16_t cnt_in;
+    volatile  int16_t cnt_out;
+} write_buffer, read_buffer;
+
+/******************************************************************************/
+static void set_bitrate(uint32_t bps)
+{
+    uint32_t baud_divisor;
+
+    baud_divisor = SystemCoreClock / (1 << (MXC_CLKMAN->sys_clk_ctrl_8_uart - 1));
+    baud_divisor /= (bps * 16);
+    CdcAcmUart->baud = baud_divisor;
+
+    baudrate = bps;
+}
+
+/******************************************************************************/
+int32_t uart_initialize(void)
+{
+    if (MXC_CLKMAN->sys_clk_ctrl_8_uart != MXC_S_CLKMAN_CLK_SCALE_DIV_4) {
+        MXC_CLKMAN->sys_clk_ctrl_8_uart = MXC_S_CLKMAN_CLK_SCALE_DIV_4;
+    }
+    // Configure GPIO for UART
+    MXC_IOMAN->uart0_req = ((0 << MXC_F_IOMAN_UART0_REQ_IO_MAP_POS) | MXC_F_IOMAN_UART0_REQ_IO_REQ);
+    while (MXC_IOMAN->uart0_ack != ((0 << MXC_F_IOMAN_UART0_REQ_IO_MAP_POS) | MXC_F_IOMAN_UART0_REQ_IO_REQ));
+
+    // Disable TX and RX fifos
+    CdcAcmUart->ctrl &= ~(MXC_F_UART_CTRL_RX_FIFO_EN | MXC_F_UART_CTRL_TX_FIFO_EN);
+
+    // Disable interrupts
+    CdcAcmUart->inten = 0;
+    CdcAcmUart->intfl = CdcAcmUart->intfl;
+
+    // Set the parity, size, stop and flow configuration
+    CdcAcmUart->ctrl |= (MXC_S_UART_CTRL_DATA_SIZE_8_BITS | MXC_S_UART_CTRL_PARITY_DISABLE);
+
+    // Set receive fifo threshold to 0
+    CdcAcmUart->rx_fifo_ctrl &= ~MXC_F_UART_RX_FIFO_CTRL_FIFO_AF_LVL;
+    CdcAcmUart->rx_fifo_ctrl |= (0 << MXC_F_UART_RX_FIFO_CTRL_FIFO_AF_LVL_POS);
+
+    // Enable TX and RX fifos
+    CdcAcmUart->ctrl |= (MXC_F_UART_CTRL_RX_FIFO_EN | MXC_F_UART_CTRL_TX_FIFO_EN);
+
+    NVIC_EnableIRQ(CdcAcmUartIrqNumber);
+
+    // Set transmit almost empty level to three-quarters of the fifo size
+    CdcAcmUart->tx_fifo_ctrl &= ~MXC_F_UART_TX_FIFO_CTRL_FIFO_AE_LVL;
+    CdcAcmUart->tx_fifo_ctrl |= (MXC_UART_FIFO_DEPTH - (MXC_UART_FIFO_DEPTH >> 2)) << MXC_F_UART_TX_FIFO_CTRL_FIFO_AE_LVL_POS;
+
+    // Enable TX and RX interrupts
+    CdcAcmUart->inten = (MXC_F_UART_INTEN_RX_FIFO_NOT_EMPTY | MXC_F_UART_INTFL_RX_FIFO_OVERFLOW | MXC_F_UART_INTEN_TX_FIFO_AE);
+
+    // Enable UART
+    CdcAcmUart->ctrl |= MXC_F_UART_CTRL_UART_EN;
+
+    return 1;
+}
+
+/******************************************************************************/
+int32_t uart_uninitialize(void)
+{
+    // Disable UART
+    CdcAcmUart->ctrl &= ~MXC_F_UART_CTRL_UART_EN;
+
+    // Disable interrupts
+    CdcAcmUart->inten = 0;
+    NVIC_DisableIRQ(CdcAcmUartIrqNumber);
+
+    // Clear buffers
+    memset(&write_buffer, 0, sizeof(write_buffer));
+    memset(&read_buffer, 0, sizeof(read_buffer));
+
+    return 1;
+}
+
+/******************************************************************************/
+void uart_set_control_line_state(uint16_t ctrl_bmp)
+{
+}
+
+/******************************************************************************/
+int32_t uart_reset(void)
+{
+    // Clear buffers
+    memset(&write_buffer, 0, sizeof(write_buffer));
+    memset(&read_buffer, 0, sizeof(read_buffer));
+
+    return 1;
+}
+
+/******************************************************************************/
+int32_t uart_set_configuration(UART_Configuration *config)
+{
+    uint32_t ctrl;
+
+    // Get current configuration; clearing parameters that may be configured here
+    ctrl = CdcAcmUart->ctrl & ~(MXC_F_UART_CTRL_PARITY |
+                                MXC_F_UART_CTRL_DATA_SIZE |
+                                MXC_F_UART_CTRL_EXTRA_STOP |
+                                MXC_F_UART_CTRL_CTS_EN |
+                                MXC_F_UART_CTRL_RTS_EN);
+
+    switch (config->Parity) {
+        case UART_PARITY_NONE: break;
+        case UART_PARITY_ODD: ctrl |= MXC_S_UART_CTRL_PARITY_ODD;
+        case UART_PARITY_EVEN: ctrl |= MXC_S_UART_CTRL_PARITY_EVEN;
+        case UART_PARITY_MARK: return 0;
+        case UART_PARITY_SPACE: return 0;
+    }
+
+    switch (config->DataBits) {
+        case UART_DATA_BITS_5:  ctrl |= MXC_S_UART_CTRL_DATA_SIZE_5_BITS; break;
+        case UART_DATA_BITS_6:  ctrl |= MXC_S_UART_CTRL_DATA_SIZE_6_BITS; break;
+        case UART_DATA_BITS_7:  ctrl |= MXC_S_UART_CTRL_DATA_SIZE_7_BITS; break;
+        case UART_DATA_BITS_8:  ctrl |= MXC_S_UART_CTRL_DATA_SIZE_8_BITS; break;
+        case UART_DATA_BITS_16: return 0;
+    }
+
+    switch (config->StopBits) {
+        case UART_STOP_BITS_1:    break;
+        case UART_STOP_BITS_1_5:
+        case UART_STOP_BITS_2:    ctrl |= MXC_F_UART_CTRL_EXTRA_STOP; break;
+    }
+
+    switch (config->FlowControl) {
+        case UART_FLOW_CONTROL_NONE:      break;
+        case UART_FLOW_CONTROL_RTS_CTS:   return 0;
+        case UART_FLOW_CONTROL_XON_XOFF:  return 0;
+    }
+
+    set_bitrate(config->Baudrate);
+
+    // Set the new configuration
+    CdcAcmUart->ctrl = ctrl;
+
+    return 1;
+}
+
+/******************************************************************************/
+int32_t uart_get_configuration(UART_Configuration *config)
+{
+    uint32_t ctrl;
+
+    // Capture current configuration
+    ctrl = CdcAcmUart->ctrl;
+
+    if (!(ctrl & MXC_S_UART_CTRL_PARITY_DISABLE)) {
+        config->Parity = UART_PARITY_NONE;
+    } else if (ctrl & MXC_S_UART_CTRL_PARITY_ODD) {
+        config->Parity = UART_PARITY_ODD;
+    } else {
+        // Note both EVEN and MARK parity are captured here
+        config->Parity = UART_PARITY_EVEN;
+    }
+
+    switch (ctrl & MXC_F_UART_CTRL_DATA_SIZE) {
+        case MXC_S_UART_CTRL_DATA_SIZE_5_BITS: config->DataBits = UART_DATA_BITS_5; break;
+        case MXC_S_UART_CTRL_DATA_SIZE_6_BITS: config->DataBits = UART_DATA_BITS_6; break;
+        case MXC_S_UART_CTRL_DATA_SIZE_7_BITS: config->DataBits = UART_DATA_BITS_7; break;
+        case MXC_S_UART_CTRL_DATA_SIZE_8_BITS: config->DataBits = UART_DATA_BITS_8; break;
+    }
+
+    if (!(ctrl & MXC_F_UART_CTRL_EXTRA_STOP)) {
+        config->StopBits = UART_STOP_BITS_1;
+    } else {
+        config->StopBits = UART_STOP_BITS_2;
+    }
+
+    if ((ctrl & (MXC_F_UART_CTRL_CTS_EN | MXC_F_UART_CTRL_RTS_EN)) == (MXC_F_UART_CTRL_CTS_EN | MXC_F_UART_CTRL_RTS_EN)) {
+        config->FlowControl = UART_FLOW_CONTROL_RTS_CTS;
+    } else {
+        // Not true if only one of ...CST_EN and ...RTS_EN are asserted
+        config->FlowControl = UART_FLOW_CONTROL_NONE;
+    }
+
+    config->Baudrate = baudrate;
+
+    return 1;
+}
+
+/******************************************************************************/
+int32_t uart_write_free(void)
+{
+    return BUFFER_SIZE - (write_buffer.cnt_in - write_buffer.cnt_out);
+}
+
+/******************************************************************************/
+int32_t uart_write_data(uint8_t *data, uint16_t size)
+{
+    uint16_t xfer_count = size;
+
+    NVIC_DisableIRQ(CdcAcmUartIrqNumber);
+    if (write_buffer.cnt_in == write_buffer.cnt_out) {
+        while ((((CdcAcmUart->tx_fifo_ctrl & MXC_F_UART_TX_FIFO_CTRL_FIFO_ENTRY) >> MXC_F_UART_TX_FIFO_CTRL_FIFO_ENTRY_POS) < MXC_UART_FIFO_DEPTH) &&
+                     (xfer_count > 0)) {
+            CdcAcmUart->intfl = MXC_F_UART_INTFL_TX_FIFO_AE;
+            CdcAcmUartFifo->tx = *data++;
+            xfer_count--;
+        }
+    }
+    NVIC_EnableIRQ(CdcAcmUartIrqNumber);
+
+    while (xfer_count > 0) {
+        if ((write_buffer.cnt_in - write_buffer.cnt_out) < BUFFER_SIZE) {
+            write_buffer.data[write_buffer.idx_in++] = *data++;
+            write_buffer.idx_in &= (BUFFER_SIZE - 1);
+            write_buffer.cnt_in++;
+            xfer_count--;
+        } else {
+            break;
+        }
+    }
+    return size - xfer_count;
+}
+
+/******************************************************************************/
+int32_t uart_read_data(uint8_t *data, uint16_t size)
+{
+    int32_t cnt;
+
+    for (cnt = 0; (cnt < size) && (read_buffer.cnt_in != read_buffer.cnt_out); cnt++) {
+        *data++ = read_buffer.data[read_buffer.idx_out++];
+        read_buffer.idx_out &= (BUFFER_SIZE - 1);
+        read_buffer.cnt_out++;
+    }
+
+    return cnt;
+}
+
+/******************************************************************************/
+void UART0_IRQHandler(void)
+{
+    /* Capture interrupt flag state at entry */
+    uint32_t intfl = CdcAcmUart->intfl;
+    /* Clear interrupts that will be serviced */
+    CdcAcmUart->intfl = intfl;
+
+    if (intfl & MXC_F_UART_INTFL_RX_FIFO_OVERFLOW) {
+            read_buffer.data[read_buffer.idx_in++] = '*';
+            read_buffer.idx_in &= (BUFFER_SIZE - 1);
+            read_buffer.cnt_in++;
+    }
+
+    if (intfl & (MXC_F_UART_INTFL_RX_FIFO_NOT_EMPTY | UART_ERRORS)) {
+        while ((CdcAcmUart->rx_fifo_ctrl & MXC_F_UART_RX_FIFO_CTRL_FIFO_ENTRY) &&
+             ((read_buffer.cnt_in - read_buffer.cnt_out) < BUFFER_SIZE)) {
+            read_buffer.data[read_buffer.idx_in++] = CdcAcmUartFifo->rx;
+            CdcAcmUart->intfl = MXC_F_UART_INTFL_RX_FIFO_NOT_EMPTY;
+            read_buffer.idx_in &= (BUFFER_SIZE - 1);
+            read_buffer.cnt_in++;
+        }
+        if (((read_buffer.cnt_in - read_buffer.cnt_out) >= BUFFER_SIZE)) {
+            read_buffer.data[read_buffer.idx_in++] = '%';
+            read_buffer.idx_in &= (BUFFER_SIZE - 1);
+            read_buffer.cnt_in++;
+        }
+    }
+
+    if (intfl & MXC_F_UART_INTFL_TX_FIFO_AE) {
+        /*
+        Transfer data from write buffer to transmit fifo if
+        a) write buffer contains data and
+        b) transmit fifo is not full
+        */
+        while ((write_buffer.cnt_out != write_buffer.cnt_in) &&
+                 (((CdcAcmUart->tx_fifo_ctrl & MXC_F_UART_TX_FIFO_CTRL_FIFO_ENTRY) >> MXC_F_UART_TX_FIFO_CTRL_FIFO_ENTRY_POS) < MXC_UART_FIFO_DEPTH)) {
+            CdcAcmUartFifo->tx = write_buffer.data[write_buffer.idx_out++];
+            write_buffer.idx_out &= (BUFFER_SIZE - 1);
+            write_buffer.cnt_out++;
+        }
+    }
+}