/************************************************************************** * arch/arm/src/samv7/sam_lowputc.c * * Copyright (C) 2015 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include #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 }