Diff: mbed-dev/targets/TARGET_ONSEMI/TARGET_NCS36510/serial_api.c

Revision:

18:6a4db94011d3

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-dev/targets/TARGET_ONSEMI/TARGET_NCS36510/serial_api.c	Sun May 14 23:18:57 2017 +0000
@@ -0,0 +1,386 @@
+/**
+******************************************************************************
+* @file Serial.c
+* @brief Implementation of a 16C550 UART driver
+* @internal
+* @author ON Semiconductor
+* $Rev: 0.1 $
+* $Date: 2015-11-04 05:30:00 +0530 (Wed, 04 Nov 2015) $
+******************************************************************************
+ * Copyright 2016 Semiconductor Components Industries LLC (d/b/a “ON Semiconductor”).
+ * All rights reserved.  This software and/or documentation is licensed by ON Semiconductor
+ * under limited terms and conditions.  The terms and conditions pertaining to the software
+ * and/or documentation are available at http://www.onsemi.com/site/pdf/ONSEMI_T&C.pdf
+ * (“ON Semiconductor Standard Terms and Conditions of Sale, Section 8 Software”) and
+ * if applicable the software license agreement.  Do not use this software and/or
+ * documentation unless you have carefully read and you agree to the limited terms and
+ * conditions.  By using this software and/or documentation, you agree to the limited
+ * terms and conditions.
+*
+* THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
+* OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
+* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
+* ON SEMICONDUCTOR SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL,
+* INCIDENTAL, OR CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
+* @endinternal
+*
+* @ingroup uart_16c550
+*
+*/
+#if DEVICE_SERIAL
+
+#include "serial_api.h"
+
+#include "cmsis.h"
+#include "pinmap.h"
+#include "PeripheralPins.h"
+
+#include "mbed_assert.h"
+#include <string.h>
+#include "uart_16c550.h"
+#include "cmsis_nvic.h"
+
+static IRQn_Type Irq;
+
+uint32_t stdio_uart_inited = 0;
+serial_t stdio_uart;
+
+static uint32_t serial_irq_ids[UART_NUM] = {0};
+static uart_irq_handler irq_handler;
+static inline void uart_irq(uint8_t status, uint32_t index);
+
+
+/** Opens UART device.
+ * @details
+ * Sets the necessary registers. Set to default Baud rate 115200, 8 bit, parity None and stop bit 1.
+ *  The UART interrupt is enabled.
+ *
+ * @note The UART transmit interrupt is not enabled, because sending is controlled
+ * by the task.
+ *
+ * @param UartNum A UART device instance.
+ * @param options The options parameter containing the baud rate.
+ * @return True if opening was successful.
+ */
+
+void serial_init(serial_t *obj, PinName tx, PinName rx)
+{
+    uint16_t clockDivisor;
+
+    CrossbReg_t *CbRegOffSet;
+    PadReg_t *PadRegOffset;
+
+    //find which peripheral is associated with the rx and tx pins
+    uint32_t uart_tx = pinmap_peripheral(tx, PinMap_UART_TX);
+    uint32_t uart_rx = pinmap_peripheral(rx, PinMap_UART_RX);
+    //check if the peripherals for each pin are the same or not
+    //returns the enum associated with the peripheral
+    //in the case of this target, the enum is the base address of the peripheral
+    obj->UARTREG = (Uart16C550Reg_pt) pinmap_merge(uart_tx, uart_rx);
+    MBED_ASSERT(obj->UARTREG != (Uart16C550Reg_pt) NC);
+
+    pinmap_pinout(tx, PinMap_UART_TX);
+    pinmap_pinout(rx, PinMap_UART_RX);
+
+    /*TODO: Mac Lobdell - we should recommend using the instance method and not using base addresses as index */
+
+    if (obj->UARTREG == (Uart16C550Reg_pt)STDIO_UART) {
+        stdio_uart_inited = 1;
+        memcpy(&stdio_uart, obj, sizeof(serial_t));
+    }
+    /*TODO: determine if pullups are needed/recommended */
+    /*    if (tx != NC) {
+                pin_mode(tx, PullUp);
+      }
+        if (rx != NC) {
+                pin_mode(rx, PullUp);
+        }
+    */
+    /* Configure IOs to UART using cross bar, pad and GPIO settings */
+
+    if(obj->UARTREG == UART2REG) {
+        /* UART 2 */
+        CLOCK_ENABLE(CLOCK_UART2);
+        Irq = Uart2_IRQn;
+    } else if(obj->UARTREG == UART1REG) {
+        /* UART 1  */
+        CLOCK_ENABLE(CLOCK_UART1);
+
+        Irq = Uart1_IRQn;
+    } else {
+        MBED_ASSERT(False);
+    }
+
+    CLOCK_ENABLE(CLOCK_GPIO);
+    CLOCK_ENABLE(CLOCK_CROSSB);
+    CLOCK_ENABLE(CLOCK_PAD);
+
+    /*TODO: determine if tx and rx are used correctly in this case - this depends on the pin enum matching the position in the crossbar*/
+
+    /* Configure tx pin as UART */
+    CbRegOffSet = (CrossbReg_t*)(CROSSBREG_BASE + (tx * CROSS_REG_ADRS_BYTE_SIZE));
+    CbRegOffSet->DIOCTRL0 = CONFIGURE_AS_UART; /* tx pin as UART */
+
+    /* Configure rx pin as UART */
+    CbRegOffSet = (CrossbReg_t*)(CROSSBREG_BASE + (rx * CROSS_REG_ADRS_BYTE_SIZE));
+    CbRegOffSet->DIOCTRL0 = CONFIGURE_AS_UART; /* rx pin as UART */
+
+    /** - Set pad parameters, output drive strength, pull piece control, output drive type */
+    PadRegOffset = (PadReg_t*)(PADREG_BASE + (tx * PAD_REG_ADRS_BYTE_SIZE));
+    PadRegOffset->PADIO0.WORD = PAD_UART_TX; /* Pad setting for UART Tx */
+
+    PadRegOffset = (PadReg_t*)(PADREG_BASE + (rx * PAD_REG_ADRS_BYTE_SIZE));
+    PadRegOffset->PADIO0.WORD = PAD_UART_RX;  /* Pad settings for UART Rx */
+
+    GPIOREG->W_OUT  = (0x1 << tx); /* tx as OUT direction */
+    GPIOREG->W_IN   = (0x1 << rx); /* rx as IN directon */
+
+    CLOCK_DISABLE(CLOCK_PAD);
+    CLOCK_DISABLE(CLOCK_CROSSB);
+    CLOCK_DISABLE(CLOCK_GPIO);
+
+    /* Set the divisor value.  To do so, LCR[7] needs to be set to 1 in order to access the divisor registers.
+     * The right-shift of 4 is a division of 16, representing the oversampling rate. */
+    clockDivisor = (fClockGetPeriphClockfrequency() / UART_DEFAULT_BAUD) >> 4;
+    obj->UARTREG->LCR.WORD = 0x80;
+    obj->UARTREG->DLL = clockDivisor & 0xFF;
+    obj->UARTREG->DLM = clockDivisor >> 8;
+
+    /* Set the character width to 8 data bits, no parity, 1 stop bit.  Write the entire line control register,
+     *   effectively disabling the divisor latch. */
+    obj->UARTREG->LCR.WORD = 0x03;
+
+    /* Enable the FIFOs, reset the Tx and Rx FIFOs, set the Rx FIFO trigger level to 8 bytes, and set DMA Mode
+       to 1. */
+    obj->UARTREG->FCR.WORD = (FCR_RXFIFOTRIGGERLEVEL_8 | FCR_DMA_MODE_1 |
+                              FCR_TXFIFO_RESET | FCR_RXFIFO_RESET | FCR_FIFO_ENABLE);
+
+    /* Make a copy of the current MSR to the SCR register.  This is used from task space to determine the
+     *   flow control state. */
+    obj->UARTREG->SCR = obj->UARTREG->MSR.WORD;
+
+    if((int)obj->UARTREG == STDIO_UART) {
+        stdio_uart_inited = 1;
+        memcpy(&stdio_uart, obj, sizeof(serial_t));
+    }
+
+    NVIC_ClearPendingIRQ(Irq);
+
+    return;
+}
+
+/** Closes a UART device.
+ * @details
+ * Disables the UART interrupt.
+ *
+ * @param device The UART device to close.
+ */
+void serial_free(serial_t *obj)
+{
+    NVIC_DisableIRQ(obj->IRQType);
+}
+
+void serial_baud(serial_t *obj, int baudrate)
+{
+    /* Set the divisor value.  To do so, LCR[7] needs to be set to 1 in order to access the divisor registers.
+     * The right-shift of 4 is a division of 16, representing the oversampling rate. */
+    uint16_t clockDivisor = (fClockGetPeriphClockfrequency() / baudrate) >> 4;
+
+    obj->UARTREG->LCR.BITS.DLAB = True;
+    obj->UARTREG->DLL = clockDivisor & 0xFF;
+    obj->UARTREG->DLM = clockDivisor >> 8;
+    obj->UARTREG->LCR.BITS.DLAB = False;
+}
+
+/*
+Parity XX0 – Parity disabled; 001 – Odd Parity; 011 – Even Parity; 101 – Stick Parity, checked as 1; 111 – Stick Parity, checked as 0.
+StopBit 0 – 1 stop bit; 1 – 2 stop bits.
+DataLen 00 – 5 bits; 01 – 6 bits; 10 – 7 bits; 11 – 8 bits
+*/
+void serial_format(serial_t *obj, int data_bits, SerialParity parity, int stop_bits)
+{
+    if(data_bits >= 5 && data_bits <= 8 && parity <= 7 && stop_bits >= 1 && stop_bits <= 2) {
+        if(parity == (SerialParity)0) {
+            parity  = (SerialParity)0;
+        } else {
+            parity = (SerialParity)(parity + parity - 1) ;
+        }
+
+        obj->UARTREG->LCR.WORD |= ((((data_bits - 5) << UART_LCR_DATALEN_BIT_POS) |
+                                    (parity << UART_LCR_PARITY_BIT_POS) |
+                                    ((stop_bits - 1) << UART_LCR_STPBIT_BIT_POS)) & 0x3F);
+    } else {
+        MBED_ASSERT(False);
+    }
+}
+
+void serial_irq_handler(serial_t *obj, uart_irq_handler handler, uint32_t id)
+{
+    irq_handler = handler;
+    serial_irq_ids[obj->index] = id;
+}
+
+/******************************************************
+************* Internal IRQ functions ******************
+*******************************************************/
+void Uart1_Irq()
+{
+    uint8_t active_irq = (uint8_t)(UART1REG->LSR.WORD) & 0xFF;
+    uint8_t irq_mask = 0;
+
+    if(UART1REG->IER.WORD & UART_IER_TX_EMPTY_MASK) { /*check if TX interrupt is enabled*/
+        irq_mask |= active_irq & UART_LSR_TX_EMPTY_MASK;
+    }
+
+    if(UART1REG->IER.WORD & UART_IER_RX_DATA_READY_MASK) { /*check if RX interrupt is enabled*/
+        irq_mask |= active_irq & UART_LSR_RX_DATA_READY_MASK;
+    }
+
+    //uart_irq((uint8_t)(UART1REG->LSR.WORD & 0xFF), 0);
+    uart_irq(active_irq & irq_mask, 0);
+}
+
+void Uart2_Irq()
+{
+    uint8_t active_irq = (uint8_t)(UART2REG->LSR.WORD) & 0xFF;
+    uint8_t irq_mask = 0;
+
+    if(UART2REG->IER.WORD & UART_IER_TX_EMPTY_MASK) { /*check if TX interrupt is enabled*/
+        irq_mask |= active_irq & UART_LSR_TX_EMPTY_MASK;
+    }
+
+    if(UART2REG->IER.WORD & UART_IER_RX_DATA_READY_MASK) { /*check if RX interrupt is enabled*/
+        irq_mask |= active_irq & UART_LSR_RX_DATA_READY_MASK;
+    }
+
+    //uart_irq((uint8_t)(UART2REG->LSR.WORD & 0xFF), 1);
+    uart_irq(active_irq & irq_mask, 1);
+
+}
+
+static inline void uart_irq(uint8_t status, uint32_t index)
+{
+    if (serial_irq_ids[index] != 0) {
+        if (status & UART_LSR_TX_EMPTY_MASK) {
+            irq_handler(serial_irq_ids[index], TxIrq);
+        }
+        if (status & UART_LSR_RX_DATA_READY_MASK) {
+            irq_handler(serial_irq_ids[index], RxIrq);
+        }
+    }
+}
+/******************************************************/
+
+void serial_irq_set(serial_t *obj, SerialIrq irq, uint32_t enable)
+{
+    IRQn_Type irq_n = (IRQn_Type)0;
+    uint32_t Vector = 0;
+
+    /* Check UART number & assign irq handler */
+    if(obj->UARTREG == UART1REG) {
+        /* UART 2 */
+        Vector = (uint32_t)&Uart1_Irq;
+        irq_n = Uart1_IRQn;
+    } else if(obj->UARTREG == UART2REG) {
+        /* UART 1 */
+        Vector = (uint32_t)&Uart2_Irq;
+        irq_n = Uart2_IRQn;
+    } else {
+        MBED_ASSERT(False);
+    }
+
+    /* Check IRQ type & enable/disable accordingly */
+    if(enable) {
+        /* Enable */
+        if(irq == RxIrq) {
+            /* Rx IRQ */
+            obj->UARTREG->FCR.BITS.RX_FIFO_TRIG = 0x0;
+            obj->UARTREG->IER.BITS.RX_DATA_INT = True;
+        } else if(irq == TxIrq) {
+            /* Tx IRQ */
+            obj->UARTREG->IER.BITS.TX_HOLD_INT = True;
+        } else {
+            MBED_ASSERT(False);
+        }
+        NVIC_SetVector(irq_n, Vector);
+        NVIC_EnableIRQ(irq_n);
+    } else {
+        /* Disable */
+        NVIC_DisableIRQ(irq_n);
+        if(irq == RxIrq) {
+            /* Rx IRQ */
+            obj->UARTREG->IER.BITS.RX_DATA_INT = False;
+        } else if(irq == TxIrq) {
+            /* Tx IRQ */
+
+            obj->UARTREG->IER.BITS.TX_HOLD_INT = False;
+        } else {
+            MBED_ASSERT(False);
+        }
+    }
+}
+
+int serial_getc(serial_t *obj)
+{
+    uint8_t c;
+
+    while(!obj->UARTREG->LSR.BITS.READY);     /* Wait for received data is ready */
+    c = obj->UARTREG->RBR & 0xFF;             /* Get received character */
+    return c;
+}
+
+void serial_putc(serial_t *obj, int c)
+{
+
+    while(!obj->UARTREG->LSR.BITS.TX_HOLD_EMPTY);/* Wait till THR is empty */
+    obj->UARTREG->THR = c; /* Transmit byte */
+
+}
+
+int serial_readable(serial_t *obj)
+{
+    return obj->UARTREG->LSR.BITS.READY;
+}
+
+int serial_writable(serial_t *obj)
+{
+    return obj->UARTREG->LSR.BITS.TX_HOLD_EMPTY;
+}
+
+void serial_clear(serial_t *obj)
+{
+    /* Reset TX & RX FIFO */
+    obj->UARTREG->FCR.WORD |= ((True << UART_FCS_TX_FIFO_RST_BIT_POS) |
+                               (True << UART_FCS_RX_FIFO_RST_BIT_POS));
+}
+
+void serial_break_set(serial_t *obj)
+{
+    obj->UARTREG->LCR.BITS.BREAK = True;
+}
+
+void serial_break_clear(serial_t *obj)
+{
+    obj->UARTREG->LCR.BITS.BREAK = False;
+}
+
+void serial_pinout_tx(PinName tx)
+{
+    /* COnfigure PinNo to drive strength of 1, Push pull and pull none */
+    fPadIOCtrl(tx, 1, 0, 1);
+}
+
+/** Configure the serial for the flow control. It sets flow control in the hardware
+ *  if a serial peripheral supports it, otherwise software emulation is used.
+ *
+ * @param obj    The serial object
+ * @param type   The type of the flow control. Look at the available FlowControl types.
+ * @param rxflow The TX pin name
+ * @param txflow The RX pin name
+ */
+void serial_set_flow_control(serial_t *obj, FlowControl type, PinName rxflow, PinName txflow)
+{
+    /* TODO: This is an empty implementation for now.*/
+}
+
+#endif /* DEVICE_SERIAL  */