sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
3e3e023cf3
nuttx/arch/arm/src/lpc11xx/lpc11_lowputc.c
Gregory Nutt 9c63736c98 Standard some naming if code sectino comments
2016-02-21 18:06:09 -06:00

307 lines
9.7 KiB
C
Raw Blame History

/****************************************************************************
* arch/arm/src/lpc11xx/lpc11_lowputc.c
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 NuttX 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 OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <arch/irq.h>
#include <arch/board/board.h>
#include "up_internal.h"
#include "up_arch.h"
#include "chip/lpc11_syscon.h"
#include "chip/lpc11_uart.h"
#include "lpc11_gpio.h"
#include "lpc11_lowputc.h"
#include "lpc11_serial.h"
/****************************************************************************
* Private Definitions
****************************************************************************/
/* Select UART parameters for the selected console */
#if defined(CONFIG_UART0_SERIAL_CONSOLE)
# define CONSOLE_BASE LPC11_UART0_BASE
# define CONSOLE_BAUD CONFIG_UART0_BAUD
# define CONSOLE_BITS CONFIG_UART0_BITS
# define CONSOLE_PARITY CONFIG_UART0_PARITY
# define CONSOLE_2STOP CONFIG_UART0_2STOP
#elif defined(HAVE_SERIAL_CONSOLE)
# error "No CONFIG_UART0_SERIAL_CONSOLE Setting"
#endif
/* Get word length setting for the console */
#if CONSOLE_BITS == 5
# define CONSOLE_LCR_WLS UART_LCR_WLS_5BIT
#elif CONSOLE_BITS == 6
# define CONSOLE_LCR_WLS UART_LCR_WLS_6BIT
#elif CONSOLE_BITS == 7
# define CONSOLE_LCR_WLS UART_LCR_WLS_7BIT
#elif CONSOLE_BITS == 8
# define CONSOLE_LCR_WLS UART_LCR_WLS_8BIT
#elif defined(HAVE_SERIAL_CONSOLE)
# error "Invalid CONFIG_UARTn_BITS setting for console "
#endif
/* Get parity setting for the console */
#if CONSOLE_PARITY == 0
# define CONSOLE_LCR_PAR 0
#elif CONSOLE_PARITY == 1
# define CONSOLE_LCR_PAR (UART_LCR_PE|UART_LCR_PS_ODD)
#elif CONSOLE_PARITY == 2
# define CONSOLE_LCR_PAR (UART_LCR_PE|UART_LCR_PS_EVEN)
#elif CONSOLE_PARITY == 3
# define CONSOLE_LCR_PAR (UART_LCR_PE|UART_LCR_PS_STICK1)
#elif CONSOLE_PARITY == 4
# define CONSOLE_LCR_PAR (UART_LCR_PE|UART_LCR_PS_STICK0)
#elif defined(HAVE_SERIAL_CONSOLE)
# error "Invalid CONFIG_UARTn_PARITY setting for CONSOLE"
#endif
/* Get stop-bit setting for the console and UART0-3 */
#if CONSOLE_2STOP != 0
# define CONSOLE_LCR_STOP UART_LCR_STOP
#else
# define CONSOLE_LCR_STOP 0
#endif
/* LCR and FCR values for the console */
#define CONSOLE_LCR_VALUE (CONSOLE_LCR_WLS | CONSOLE_LCR_PAR | CONSOLE_LCR_STOP)
#define CONSOLE_FCR_VALUE (UART_FCR_RXTRIGGER_8 | UART_FCR_TXRST |\
UART_FCR_RXRST | UART_FCR_FIFOEN)
/****************************************************************************
* This Baud Rate configuration is based on idea suggested at LPCWare:
* www.lpcware.com/content/blog/lpc17xx-uart-simpler-way-calculate-baudrate-timming
*
* The original code is for LPC17xx but with few modifications it worked
* fine in the LPC11xx as well.
*
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Public Data
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_lowputc
*
* Description:
* Output one byte on the serial console
*
****************************************************************************/
void up_lowputc(char ch)
{
#if defined HAVE_UART && defined HAVE_SERIAL_CONSOLE
/* Wait for the transmitter to be available */
while ((getreg32(CONSOLE_BASE+LPC11_UART_LSR_OFFSET) & UART_LSR_THRE) == 0);
/* Send the character */
putreg32((uint32_t)ch, CONSOLE_BASE+LPC11_UART_THR_OFFSET);
#endif
}
/****************************************************************************
* Name: lpc11_lowsetup
*
* Description:
* This performs basic initialization of the UART used for the serial
* console. Its purpose is to get the console output available as soon
* as possible.
*
* The UART peripheral is configured using the following registers:
* 1. Pins: For the LPC111x/101/201/301 parts, the UART pins must be
* configured in the IOCONFIG register block before the UART clocks can
* be enabled in the SYSAHBCLKCTRL register. For all other parts, no
* special enabling sequence is required.
* 2. Power: In the SYSAHBCLKCTRL register, set bit 12.
* On reset, UART is disabled.
* 3. Peripheral clock: Enable the UART peripheral clock by writing to the
* UARTCLKDIV register.
*
****************************************************************************/
void lpc11_lowsetup(void)
{
#ifdef HAVE_UART
uint32_t regval;
uint32_t coreclk = LPC11_MCLK;
uint32_t rate16 = 16 * CONSOLE_BAUD;
uint32_t dval;
uint32_t mval;
uint32_t dl;
/* Enable clock for GPIO and I/O block */
regval = getreg32(LPC11_SYSCON_SYSAHBCLKCTRL);
regval |= (SYSCON_SYSAHBCLKCTRL_GPIO | SYSCON_SYSAHBCLKCTRL_IOCON);
putreg32(regval, LPC11_SYSCON_SYSAHBCLKCTRL);
#if defined(CONFIG_UART0_SERIAL_CONSOLE)
/* Step 1: Pins configuration */
lpc11_configgpio(GPIO_UART0_TXD);
lpc11_configgpio(GPIO_UART0_RXD);
#endif
/* Step 2: Enable power for all console UART and disable power for
* other UARTs.
*/
regval = getreg32(LPC11_SYSCON_SYSAHBCLKCTRL);
#if defined(CONFIG_UART0_SERIAL_CONSOLE)
regval |= SYSCON_SYSAHBCLKCTRL_UART;
#endif
putreg32(regval, LPC11_SYSCON_SYSAHBCLKCTRL);
/* Step 3: Enable peripheral clocking for the console UART and disable
* clocking for all other UARTs
*/
/* Don't divide the UART Clock it is be equal to Peripheral Clock */
putreg32(1, LPC11_SYSCON_UARTCLKDIV);
/* Configure the console (only) */
#if defined(HAVE_SERIAL_CONSOLE) && !defined(CONFIG_SUPPRESS_UART_CONFIG)
/* Clear fifos */
putreg32(UART_FCR_RXRST | UART_FCR_TXRST,
CONSOLE_BASE + LPC11_UART_FCR_OFFSET);
/* Set trigger */
putreg32(UART_FCR_FIFOEN | UART_FCR_RXTRIGGER_8,
CONSOLE_BASE + LPC11_UART_FCR_OFFSET);
/* Set up the LCR and set DLAB=1 */
putreg32(CONSOLE_LCR_VALUE | UART_LCR_DLAB,
CONSOLE_BASE + LPC11_UART_LCR_OFFSET);
/* Configure the Baud rate
*
* The fractional is calculated as
* (PCLK % (16 * Baudrate)) / (16 * Baudrate)
*/
dval = coreclk % rate16;
/* The PCLK / (16 * Baudrate) is fractional
* dval = pclk % rate16
* mval = rate16
* now normalize the ratio
* dval / mval = 1 / new_mval
* new_mval = mval / dval;
* new_dval = 1
*/
if (dval > 0)
{
mval = rate16 / dval;
dval = 1;
if (mval > 12)
{
dval = 0;
}
}
dval &= 0xf;
mval &= 0xf;
dl = coreclk / (rate16 + rate16 * dval / mval);
/* Set the BAUD divisor */
putreg32(dl & 0xff, CONSOLE_BASE + LPC11_UART_DLL_OFFSET);
putreg32(dl >> 8, CONSOLE_BASE + LPC11_UART_DLM_OFFSET);
/* Set the BAUD fractional */
putreg32((mval << UART_FDR_MULVAL_SHIFT) |
(dval << UART_FDR_DIVADDVAL_SHIFT),
CONSOLE_BASE + LPC11_UART_FDR_OFFSET);
/* Clear DLAB */
putreg32(CONSOLE_LCR_VALUE, CONSOLE_BASE + LPC11_UART_LCR_OFFSET);
/* Configure the FIFOs */
putreg32(UART_FCR_RXTRIGGER_8 | UART_FCR_TXRST | UART_FCR_RXRST |
UART_FCR_FIFOEN,
CONSOLE_BASE + LPC11_UART_FCR_OFFSET);
#endif
#endif /* HAVE_UART */
}
Reference in New Issue View Git Blame Copy Permalink