/**************************************************************************
* arch/arm/src/samv7/sam_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 "sam_config.h"
#include "sam_gpio.h"
#include "sam_periphclks.h"
#include "sam_lowputc.h"
#include "chip/sam_uart.h"
#include "chip/sam_pinmap.h"
/**************************************************************************
* Pre-processor Definitions
**************************************************************************/
/* Configuration **********************************************************/
#ifdef HAVE_SERIAL_CONSOLE
/* BAUD definitions
*
* The source clock is selectable and could be one of:
*
* - The peripheral clock
* - A division of the peripheral clock, where the divider is product-
* dependent, but generally set to 8
* - A processor/peripheral independent clock source fully programmable
* provided by PMC (PCK)
* - The external clock, available on the SCK pin
*
* Only the first two options are supported by this driver. The divided
* peripheral clock is only used for very low BAUD selections.
*/
#define FAST_USART_CLOCK BOARD_MCK_FREQUENCY
#define SLOW_USART_CLOCK (BOARD_MCK_FREQUENCY >> 3)
/* Select USART parameters for the selected console */
# if defined(CONFIG_UART0_SERIAL_CONSOLE)
# define SAM_CONSOLE_BASE SAM_UART0_BASE
# define SAM_CONSOLE_BAUD CONFIG_UART0_BAUD
# define SAM_CONSOLE_BITS CONFIG_UART0_BITS
# define SAM_CONSOLE_PARITY CONFIG_UART0_PARITY
# define SAM_CONSOLE_2STOP CONFIG_UART0_2STOP
# elif defined(CONFIG_UART1_SERIAL_CONSOLE)
# define SAM_CONSOLE_BASE SAM_UART1_BASE
# define SAM_CONSOLE_BAUD CONFIG_UART1_BAUD
# define SAM_CONSOLE_BITS CONFIG_UART1_BITS
# define SAM_CONSOLE_PARITY CONFIG_UART1_PARITY
# define SAM_CONSOLE_2STOP CONFIG_UART1_2STOP
# elif defined(CONFIG_UART2_SERIAL_CONSOLE)
# define SAM_CONSOLE_BASE SAM_UART2_BASE
# define SAM_CONSOLE_BAUD CONFIG_UART2_BAUD
# define SAM_CONSOLE_BITS CONFIG_UART2_BITS
# define SAM_CONSOLE_PARITY CONFIG_UART2_PARITY
# define SAM_CONSOLE_2STOP CONFIG_UART2_2STOP
# elif defined(CONFIG_UART3_SERIAL_CONSOLE)
# define SAM_CONSOLE_BASE SAM_UART3_BASE
# define SAM_CONSOLE_BAUD CONFIG_UART3_BAUD
# define SAM_CONSOLE_BITS CONFIG_UART3_BITS
# define SAM_CONSOLE_PARITY CONFIG_UART3_PARITY
# define SAM_CONSOLE_2STOP CONFIG_UART3_2STOP
# elif defined(CONFIG_UART4_SERIAL_CONSOLE)
# define SAM_CONSOLE_BASE SAM_UART4_BASE
# define SAM_CONSOLE_BAUD CONFIG_UART4_BAUD
# define SAM_CONSOLE_BITS CONFIG_UART4_BITS
# define SAM_CONSOLE_PARITY CONFIG_UART4_PARITY
# define SAM_CONSOLE_2STOP CONFIG_UART4_2STOP
# elif defined(CONFIG_USART0_SERIAL_CONSOLE)
# define SAM_CONSOLE_BASE SAM_USART0_BASE
# define SAM_CONSOLE_BAUD CONFIG_USART0_BAUD
# define SAM_CONSOLE_BITS CONFIG_USART0_BITS
# define SAM_CONSOLE_PARITY CONFIG_USART0_PARITY
# define SAM_CONSOLE_2STOP CONFIG_USART0_2STOP
# elif defined(CONFIG_USART1_SERIAL_CONSOLE)
# define SAM_CONSOLE_BASE SAM_USART1_BASE
# define SAM_CONSOLE_BAUD CONFIG_USART1_BAUD
# define SAM_CONSOLE_BITS CONFIG_USART1_BITS
# define SAM_CONSOLE_PARITY CONFIG_USART1_PARITY
# define SAM_CONSOLE_2STOP CONFIG_USART1_2STOP
# elif defined(CONFIG_USART2_SERIAL_CONSOLE)
# define SAM_CONSOLE_BASE SAM_USART2_BASE
# define SAM_CONSOLE_BAUD CONFIG_USART2_BAUD
# define SAM_CONSOLE_BITS CONFIG_USART2_BITS
# define SAM_CONSOLE_PARITY CONFIG_USART2_PARITY
# define SAM_CONSOLE_2STOP CONFIG_USART2_2STOP
# else
# error "No CONFIG_U[S]ARTn_SERIAL_CONSOLE Setting"
# endif
/* Select the settings for the mode register */
# if SAM_CONSOLE_BITS == 5
# define MR_CHRL_VALUE UART_MR_CHRL_5BITS /* 5 bits */
# elif SAM_CONSOLE_BITS == 6
# define MR_CHRL_VALUE UART_MR_CHRL_6BITS /* 6 bits */
# elif SAM_CONSOLE_BITS == 7
# define MR_CHRL_VALUE UART_MR_CHRL_7BITS /* 7 bits */
# elif SAM_CONSOLE_BITS == 8
# define MR_CHRL_VALUE UART_MR_CHRL_8BITS /* 8 bits */
# elif SAM_CONSOLE_BITS == 9 && !defined(CONFIG_UART0_SERIAL_CONSOLE) && \
!defined(CONFIG_UART1_SERIAL_CONSOLE)
# define MR_CHRL_VALUE UART_MR_MODE9
# else
# error "Invalid number of bits"
# endif
# if SAM_CONSOLE_PARITY == 1
# define MR_PAR_VALUE UART_MR_PAR_ODD
# elif SAM_CONSOLE_PARITY == 2
# define MR_PAR_VALUE UART_MR_PAR_EVEN
# else
# define MR_PAR_VALUE UART_MR_PAR_NONE
# endif
# if SAM_CONSOLE_2STOP != 0
# define MR_NBSTOP_VALUE UART_MR_NBSTOP_2
# else
# define MR_NBSTOP_VALUE UART_MR_NBSTOP_1
# endif
# define MR_VALUE (UART_MR_MODE_NORMAL | UART_MR_USCLKS_MCK | \
MR_CHRL_VALUE | MR_PAR_VALUE | MR_NBSTOP_VALUE)
#endif /* HAVE_SERIAL_CONSOLE */
/**************************************************************************
* Private Types
**************************************************************************/
/**************************************************************************
* Private Function Prototypes
**************************************************************************/
/**************************************************************************
* Global Variables
**************************************************************************/
/**************************************************************************
* Private Variables
**************************************************************************/
/**************************************************************************
* Private Functions
**************************************************************************/
/**************************************************************************
* Public Functions
**************************************************************************/
/**************************************************************************
* Name: up_lowputc
*
* Description:
* Output one byte on the serial console
*
**************************************************************************/
void up_lowputc(char ch)
{
#ifdef HAVE_SERIAL_CONSOLE
irqstate_t flags;
for (;;)
{
/* Wait for the transmitter to be available */
while ((getreg32(SAM_CONSOLE_BASE + SAM_UART_SR_OFFSET) &
UART_INT_TXEMPTY) == 0);
/* Disable interrupts so that the test and the transmission are
* atomic.
*/
flags = irqsave();
if ((getreg32(SAM_CONSOLE_BASE + SAM_UART_SR_OFFSET) &
UART_INT_TXEMPTY) != 0)
{
/* Send the character */
putreg32((uint32_t)ch, SAM_CONSOLE_BASE + SAM_UART_THR_OFFSET);
irqrestore(flags);
return;
}
irqrestore(flags);
}
#endif
}
/****************************************************************************
* Name: up_putc
*
* Description:
* Provide priority, low-level access to support OS debug writes
*
****************************************************************************/
int up_putc(int ch)
{
#ifdef HAVE_SERIAL_CONSOLE
/* Check for LF */
if (ch == '\n')
{
/* Add CR */
up_lowputc('\r');
}
up_lowputc(ch);
#endif
return ch;
}
/**************************************************************************
* Name: sam_lowsetup
*
* Description:
* This performs basic initialization of the USART used for the serial
* console. Its purpose is to get the console output availabe as soon
* as possible.
*
**************************************************************************/
void sam_lowsetup(void)
{
#if defined(HAVE_SERIAL_CONSOLE) && !defined(CONFIG_SUPPRESS_UART_CONFIG)
uint64_t divb3;
uint32_t intpart;
uint32_t fracpart;
uint32_t regval;
#endif
/* Enable clocking for all selected UART/USARTs */
#ifdef CONFIG_SAMV7_UART0
sam_uart0_enableclk();
#endif
#ifdef CONFIG_SAMV7_UART1
sam_uart1_enableclk();
#endif
#ifdef CONFIG_SAMV7_UART2
sam_uart2_enableclk();
#endif
#ifdef CONFIG_SAMV7_UART3
sam_uart3_enableclk();
#endif
#ifdef CONFIG_SAMV7_UART4
sam_uart4_enableclk();
#endif
#ifdef CONFIG_SAMV7_USART0
sam_usart0_enableclk();
#endif
#ifdef CONFIG_SAMV7_USART1
sam_usart1_enableclk();
#endif
#ifdef CONFIG_SAMV7_USART2
sam_usart2_enableclk();
#endif
/* Configure UART pins for all selected UART/USARTs */
#ifdef CONFIG_SAMV7_UART0
(void)sam_configgpio(GPIO_UART0_RXD);
(void)sam_configgpio(GPIO_UART0_TXD);
#endif
#ifdef CONFIG_SAMV7_UART1
(void)sam_configgpio(GPIO_UART1_RXD);
(void)sam_configgpio(GPIO_UART1_TXD);
#endif
#ifdef CONFIG_SAMV7_UART2
(void)sam_configgpio(GPIO_UART2_RXD);
(void)sam_configgpio(GPIO_UART2_TXD);
#endif
#ifdef CONFIG_SAMV7_UART3
(void)sam_configgpio(GPIO_UART3_RXD);
(void)sam_configgpio(GPIO_UART3_TXD);
#endif
#ifdef CONFIG_SAMV7_UART4
(void)sam_configgpio(GPIO_UART4_RXD);
(void)sam_configgpio(GPIO_UART4_TXD);
#endif
#ifdef CONFIG_SAMV7_USART0
(void)sam_configgpio(GPIO_USART0_RXD);
(void)sam_configgpio(GPIO_USART0_TXD);
#ifdef CONFIG_USART0_OFLOWCONTROL
(void)sam_configgpio(GPIO_USART0_CTS);
#endif
#ifdef CONFIG_USART0_IFLOWCONTROL
(void)sam_configgpio(GPIO_USART0_RTS);
#endif
#endif
#ifdef CONFIG_SAMV7_USART1
(void)sam_configgpio(GPIO_USART1_RXD);
(void)sam_configgpio(GPIO_USART1_TXD);
#ifdef CONFIG_USART1_OFLOWCONTROL
(void)sam_configgpio(GPIO_USART1_CTS);
#endif
#ifdef CONFIG_USART1_IFLOWCONTROL
(void)sam_configgpio(GPIO_USART1_RTS);
#endif
#endif
#ifdef CONFIG_SAMV7_USART2
(void)sam_configgpio(GPIO_USART2_RXD);
(void)sam_configgpio(GPIO_USART2_TXD);
#ifdef CONFIG_USART2_OFLOWCONTROL
(void)sam_configgpio(GPIO_USART2_CTS);
#endif
#ifdef CONFIG_USART2_IFLOWCONTROL
(void)sam_configgpio(GPIO_USART2_RTS);
#endif
#endif
/* Configure the console (only) */
#if defined(HAVE_SERIAL_CONSOLE) && !defined(CONFIG_SUPPRESS_UART_CONFIG)
/* Reset and disable receiver and transmitter */
putreg32((UART_CR_RSTRX | UART_CR_RSTTX | UART_CR_RXDIS | UART_CR_TXDIS),
SAM_CONSOLE_BASE + SAM_UART_CR_OFFSET);
/* Disable all interrupts */
putreg32(0xffffffff, SAM_CONSOLE_BASE + SAM_UART_IDR_OFFSET);
/* Set up the mode register */
putreg32(MR_VALUE, SAM_CONSOLE_BASE + SAM_UART_MR_OFFSET);
/* Configure the console baud:
*
* Fbaud = USART_CLOCK / (16 * divisor)
* divisor = USART_CLOCK / (16 * Fbaud)
*
* NOTE: Oversampling by 8 is not supported. This may limit BAUD rates
* for lower USART clocks.
*/
divb3 = ((FAST_USART_CLOCK + (SAM_CONSOLE_BAUD << 3)) << 3) /
(SAM_CONSOLE_BAUD << 4);
intpart = (divb3 >> 3);
fracpart = (divb3 & 7);
/* Retain the fast MR peripheral clock UNLESS unless using that clock
* would result in an excessively large divider.
*
* REVISIT: The fractional divider is not used.
*/
if ((intpart & ~UART_BRGR_CD_MASK) != 0)
{
/* Use the divided USART clock */
divb3 = ((SLOW_USART_CLOCK + (SAM_CONSOLE_BAUD << 3)) << 3) /
(SAM_CONSOLE_BAUD << 4);
intpart = (divb3 >> 3);
fracpart = (divb3 & 7);
/* Re-select the clock source */
regval = getreg32(SAM_CONSOLE_BASE + SAM_UART_MR_OFFSET);
regval &= ~UART_MR_USCLKS_MASK;
regval |= UART_MR_USCLKS_MCKDIV;
putreg32(regval, SAM_CONSOLE_BASE + SAM_UART_MR_OFFSET);
}
/* Save the BAUD divider (the fractional part is not used for UARTs) */
regval = UART_BRGR_CD(intpart) | UART_BRGR_FP(fracpart);
putreg32(regval, SAM_CONSOLE_BASE + SAM_UART_BRGR_OFFSET);
/* Enable receiver & transmitter */
putreg32((UART_CR_RXEN | UART_CR_TXEN),
SAM_CONSOLE_BASE + SAM_UART_CR_OFFSET);
#endif
}
