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osd-contiki/cpu/cc2538/dev/uart.c
Benoît Thébaudeau d93d129da6 cc2538: uart: Make it possible to use several UARTs simultaneously 
This avoids the limitation of having a single UART available at runtime, without
duplicating code.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
2014-04-17 18:53:44 +02:00

386 lines
12 KiB
C
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/*
* Copyright (c) 2012, Texas Instruments Incorporated - http://www.ti.com/
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* \addtogroup cc2538-uart
* @{
*
* \file
* Implementation of the cc2538 UART driver
*/
#include "contiki.h"
#include "sys/energest.h"
#include "dev/sys-ctrl.h"
#include "dev/ioc.h"
#include "dev/gpio.h"
#include "dev/uart.h"
#include "lpm.h"
#include "reg.h"
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
#ifndef UART0_RX_PORT
#define UART0_RX_PORT (-1)
#endif
#ifndef UART0_RX_PIN
#define UART0_RX_PIN (-1)
#endif
#if UART0_RX_PORT >= 0 && UART0_RX_PIN < 0 || \
UART0_RX_PORT < 0 && UART0_RX_PIN >= 0
#error Both UART0_RX_PORT and UART0_RX_PIN must be valid or invalid
#endif
#ifndef UART0_TX_PORT
#define UART0_TX_PORT (-1)
#endif
#ifndef UART0_TX_PIN
#define UART0_TX_PIN (-1)
#endif
#if UART0_TX_PORT >= 0 && UART0_TX_PIN < 0 || \
UART0_TX_PORT < 0 && UART0_TX_PIN >= 0
#error Both UART0_TX_PORT and UART0_TX_PIN must be valid or invalid
#endif
#if UART0_RX_PORT >= 0 && UART0_TX_PORT < 0 || \
UART0_RX_PORT < 0 && UART0_TX_PORT >= 0
#error Both UART0_RX and UART0_TX pads must be valid or invalid
#endif
#if UART_IN_USE(0) && UART0_RX_PORT < 0
#error Contiki is configured to use UART0, but its pads are not valid
#endif
#ifndef UART1_RX_PORT
#define UART1_RX_PORT (-1)
#endif
#ifndef UART1_RX_PIN
#define UART1_RX_PIN (-1)
#endif
#if UART1_RX_PORT >= 0 && UART1_RX_PIN < 0 || \
UART1_RX_PORT < 0 && UART1_RX_PIN >= 0
#error Both UART1_RX_PORT and UART1_RX_PIN must be valid or invalid
#endif
#ifndef UART1_TX_PORT
#define UART1_TX_PORT (-1)
#endif
#ifndef UART1_TX_PIN
#define UART1_TX_PIN (-1)
#endif
#if UART1_TX_PORT >= 0 && UART1_TX_PIN < 0 || \
UART1_TX_PORT < 0 && UART1_TX_PIN >= 0
#error Both UART1_TX_PORT and UART1_TX_PIN must be valid or invalid
#endif
#if UART1_RX_PORT >= 0 && UART1_TX_PORT < 0 || \
UART1_RX_PORT < 0 && UART1_TX_PORT >= 0
#error Both UART1_RX and UART1_TX pads must be valid or invalid
#endif
#if UART_IN_USE(1) && UART1_RX_PORT < 0
#error Contiki is configured to use UART1, but its pads are not valid
#endif
#ifndef UART1_CTS_PORT
#define UART1_CTS_PORT (-1)
#endif
#ifndef UART1_CTS_PIN
#define UART1_CTS_PIN (-1)
#endif
#if UART1_CTS_PORT >= 0 && UART1_CTS_PIN < 0 || \
UART1_CTS_PORT < 0 && UART1_CTS_PIN >= 0
#error Both UART1_CTS_PORT and UART1_CTS_PIN must be valid or invalid
#endif
#ifndef UART1_RTS_PORT
#define UART1_RTS_PORT (-1)
#endif
#ifndef UART1_RTS_PIN
#define UART1_RTS_PIN (-1)
#endif
#if UART1_RTS_PORT >= 0 && UART1_RTS_PIN < 0 || \
UART1_RTS_PORT < 0 && UART1_RTS_PIN >= 0
#error Both UART1_RTS_PORT and UART1_RTS_PIN must be valid or invalid
#endif
/*---------------------------------------------------------------------------*/
/*
* Baud rate defines used in uart_init() to set the values of UART_IBRD and
* UART_FBRD in order to achieve the configured baud rates.
*/
#define UART_CLOCK_RATE 16000000 /* 16 MHz */
#define UART_CTL_HSE_VALUE 0
#define UART_CTL_VALUE (UART_CTL_RXE | UART_CTL_TXE | (UART_CTL_HSE_VALUE << 5))
/* DIV_ROUND() divides integers while avoiding a rounding error: */
#define DIV_ROUND(num, denom) (((num) + (denom) / 2) / (denom))
#define BAUD2BRD(baud) DIV_ROUND(UART_CLOCK_RATE << (UART_CTL_HSE_VALUE + 2), (baud))
#define BAUD2IBRD(baud) (BAUD2BRD(baud) >> 6)
#define BAUD2FBRD(baud) (BAUD2BRD(baud) & 0x3f)
/*---------------------------------------------------------------------------*/
typedef struct {
int8_t port;
int8_t pin;
} uart_pad_t;
typedef struct {
uint32_t sys_ctrl_rcgcuart_uart;
uint32_t sys_ctrl_scgcuart_uart;
uint32_t sys_ctrl_dcgcuart_uart;
uint32_t base;
uint32_t ioc_uartrxd_uart;
uint32_t ioc_pxx_sel_uart_txd;
uint32_t ibrd;
uint32_t fbrd;
uart_pad_t rx;
uart_pad_t tx;
uart_pad_t cts;
uart_pad_t rts;
uint8_t nvic_int;
} uart_regs_t;
/*---------------------------------------------------------------------------*/
static const uart_regs_t uart_regs[UART_INSTANCE_COUNT] = {
{
.sys_ctrl_rcgcuart_uart = SYS_CTRL_RCGCUART_UART0,
.sys_ctrl_scgcuart_uart = SYS_CTRL_SCGCUART_UART0,
.sys_ctrl_dcgcuart_uart = SYS_CTRL_DCGCUART_UART0,
.base = UART_0_BASE,
.ioc_uartrxd_uart = IOC_UARTRXD_UART0,
.ioc_pxx_sel_uart_txd = IOC_PXX_SEL_UART0_TXD,
.ibrd = BAUD2IBRD(UART0_CONF_BAUD_RATE),
.fbrd = BAUD2FBRD(UART0_CONF_BAUD_RATE),
.rx = {UART0_RX_PORT, UART0_RX_PIN},
.tx = {UART0_TX_PORT, UART0_TX_PIN},
.cts = {-1, -1},
.rts = {-1, -1},
.nvic_int = NVIC_INT_UART0
}, {
.sys_ctrl_rcgcuart_uart = SYS_CTRL_RCGCUART_UART1,
.sys_ctrl_scgcuart_uart = SYS_CTRL_SCGCUART_UART1,
.sys_ctrl_dcgcuart_uart = SYS_CTRL_DCGCUART_UART1,
.base = UART_1_BASE,
.ioc_uartrxd_uart = IOC_UARTRXD_UART1,
.ioc_pxx_sel_uart_txd = IOC_PXX_SEL_UART1_TXD,
.ibrd = BAUD2IBRD(UART1_CONF_BAUD_RATE),
.fbrd = BAUD2FBRD(UART1_CONF_BAUD_RATE),
.rx = {UART1_RX_PORT, UART1_RX_PIN},
.tx = {UART1_TX_PORT, UART1_TX_PIN},
.cts = {UART1_CTS_PORT, UART1_CTS_PIN},
.rts = {UART1_RTS_PORT, UART1_RTS_PIN},
.nvic_int = NVIC_INT_UART1
}
};
static int (* input_handler[UART_INSTANCE_COUNT])(unsigned char c);
/*---------------------------------------------------------------------------*/
static void
reset(uint32_t uart_base)
{
uint32_t lchr;
/* Make sure the UART is disabled before trying to configure it */
REG(uart_base | UART_CTL) = UART_CTL_VALUE;
/* Clear error status */
REG(uart_base | UART_ECR) = 0xFF;
/* Store LCHR configuration */
lchr = REG(uart_base | UART_LCRH);
/* Flush FIFOs by clearing LCHR.FEN */
REG(uart_base | UART_LCRH) = 0;
/* Restore LCHR configuration */
REG(uart_base | UART_LCRH) = lchr;
/* UART Enable */
REG(uart_base | UART_CTL) |= UART_CTL_UARTEN;
}
/*---------------------------------------------------------------------------*/
static bool
permit_pm1(void)
{
const uart_regs_t *regs;
for(regs = &uart_regs[0]; regs < &uart_regs[UART_INSTANCE_COUNT]; regs++) {
/* Note: UART_FR.TXFE reads 0 if the UART clock is gated. */
if((REG(SYS_CTRL_RCGCUART) & regs->sys_ctrl_rcgcuart_uart) != 0 &&
(REG(regs->base | UART_FR) & UART_FR_TXFE) == 0) {
return false;
}
}
return true;
}
/*---------------------------------------------------------------------------*/
void
uart_init(uint8_t uart)
{
const uart_regs_t *regs;
if(uart >= UART_INSTANCE_COUNT) {
return;
}
regs = &uart_regs[uart];
if(regs->rx.port < 0 || regs->tx.port < 0) {
return;
}
lpm_register_peripheral(permit_pm1);
/* Enable clock for the UART while Running, in Sleep and Deep Sleep */
REG(SYS_CTRL_RCGCUART) |= regs->sys_ctrl_rcgcuart_uart;
REG(SYS_CTRL_SCGCUART) |= regs->sys_ctrl_scgcuart_uart;
REG(SYS_CTRL_DCGCUART) |= regs->sys_ctrl_dcgcuart_uart;
/* Run on SYS_DIV */
REG(regs->base | UART_CC) = 0;
/*
* Select the UARTx RX pin by writing to the IOC_UARTRXD_UARTn register
*
* The value to be written will be on of the IOC_INPUT_SEL_Pxn defines from
* ioc.h. The value can also be calculated as:
*
* (port << 3) + pin
*/
REG(regs->ioc_uartrxd_uart) = (regs->rx.port << 3) + regs->rx.pin;
/*
* Pad Control for the TX pin:
* - Set function to UARTn TX
* - Output Enable
*/
ioc_set_sel(regs->tx.port, regs->tx.pin, regs->ioc_pxx_sel_uart_txd);
ioc_set_over(regs->tx.port, regs->tx.pin, IOC_OVERRIDE_OE);
/* Set RX and TX pins to peripheral mode */
GPIO_PERIPHERAL_CONTROL(GPIO_PORT_TO_BASE(regs->tx.port),
GPIO_PIN_MASK(regs->tx.pin));
GPIO_PERIPHERAL_CONTROL(GPIO_PORT_TO_BASE(regs->rx.port),
GPIO_PIN_MASK(regs->rx.pin));
if(regs->cts.port >= 0 || regs->rts.port >= 0) {
/* TODO Hardware flow control */
}
/*
* UART Interrupt Masks:
* Acknowledge RX and RX Timeout
* Acknowledge Framing, Overrun and Break Errors
*/
REG(regs->base | UART_IM) = UART_IM_RXIM | UART_IM_RTIM;
REG(regs->base | UART_IM) |= UART_IM_OEIM | UART_IM_BEIM | UART_IM_FEIM;
REG(regs->base | UART_IFLS) =
UART_IFLS_RXIFLSEL_1_8 | UART_IFLS_TXIFLSEL_1_2;
/* Make sure the UART is disabled before trying to configure it */
REG(regs->base | UART_CTL) = UART_CTL_VALUE;
/* Baud Rate Generation */
REG(regs->base | UART_IBRD) = regs->ibrd;
REG(regs->base | UART_FBRD) = regs->fbrd;
/* UART Control: 8N1 with FIFOs */
REG(regs->base | UART_LCRH) = UART_LCRH_WLEN_8 | UART_LCRH_FEN;
/* UART Enable */
REG(regs->base | UART_CTL) |= UART_CTL_UARTEN;
/* Enable UART0 Interrupts */
nvic_interrupt_enable(regs->nvic_int);
}
/*---------------------------------------------------------------------------*/
void
uart_set_input(uint8_t uart, int (* input)(unsigned char c))
{
if(uart >= UART_INSTANCE_COUNT) {
return;
}
input_handler[uart] = input;
}
/*---------------------------------------------------------------------------*/
void
uart_write_byte(uint8_t uart, uint8_t b)
{
uint32_t uart_base;
if(uart >= UART_INSTANCE_COUNT) {
return;
}
uart_base = uart_regs[uart].base;
/* Block if the TX FIFO is full */
while(REG(uart_base | UART_FR) & UART_FR_TXFF);
REG(uart_base | UART_DR) = b;
}
/*---------------------------------------------------------------------------*/
void
uart_isr(uint8_t uart)
{
uint32_t uart_base;
uint16_t mis;
ENERGEST_ON(ENERGEST_TYPE_IRQ);
uart_base = uart_regs[uart].base;
/* Store the current MIS and clear all flags early, except the RTM flag.
* This will clear itself when we read out the entire FIFO contents */
mis = REG(uart_base | UART_MIS) & 0x0000FFFF;
REG(uart_base | UART_ICR) = 0x0000FFBF;
if(mis & (UART_MIS_RXMIS | UART_MIS_RTMIS)) {
while(!(REG(uart_base | UART_FR) & UART_FR_RXFE)) {
if(input_handler[uart] != NULL) {
input_handler[uart]((unsigned char)(REG(uart_base | UART_DR) & 0xFF));
} else {
/* To prevent an Overrun Error, we need to flush the FIFO even if we
* don't have an input_handler. Use mis as a data trash can */
mis = REG(uart_base | UART_DR);
}
}
} else if(mis & (UART_MIS_OEMIS | UART_MIS_BEMIS | UART_MIS_FEMIS)) {
/* ISR triggered due to some error condition */
reset(uart_base);
}
ENERGEST_OFF(ENERGEST_TYPE_IRQ);
}
/*---------------------------------------------------------------------------*/
#define UART_ISR(u) void uart##u##_isr(void) { uart_isr(u); }
UART_ISR(0)
UART_ISR(1)
/** @} */
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