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authorGregory Nutt <gnutt@nuttx.org>2014-03-08 13:29:09 -0600
committerGregory Nutt <gnutt@nuttx.org>2014-03-08 13:29:09 -0600
commit3100722cdd78ff94412a760138e2fd4fdc319548 (patch)
tree40fef8e42b9d2ad55872feb5a32ee6cbf9390a0c /nuttx/arch/arm/src/tiva/tiva_lowputc.c
parent39d69550a195f226b1985ebc62f760d286cd68c8 (diff)
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All files and functions beginning with lm_ changed to tiva_
Diffstat (limited to 'nuttx/arch/arm/src/tiva/tiva_lowputc.c')
-rw-r--r--nuttx/arch/arm/src/tiva/tiva_lowputc.c357
1 files changed, 357 insertions, 0 deletions
diff --git a/nuttx/arch/arm/src/tiva/tiva_lowputc.c b/nuttx/arch/arm/src/tiva/tiva_lowputc.c
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+/**************************************************************************
+ * arch/arm/src/tiva/tiva_lowputc.c
+ *
+ * Copyright (C) 2009-2010, 2014 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/board/board.h>
+
+#include "chip.h"
+#include "up_arch.h"
+#include "up_internal.h"
+
+#include "tiva_gpio.h"
+#include "chip/tiva_pinmap.h"
+
+#include "tiva_lowputc.h"
+
+/**************************************************************************
+ * Pre-processor Definitions
+ **************************************************************************/
+/* Configuration **********************************************************/
+
+/* Select UART parameters for the selected console */
+
+#if defined(CONFIG_UART0_SERIAL_CONSOLE)
+# define LM_CONSOLE_BASE LM_UART0_BASE
+# define LM_CONSOLE_BAUD CONFIG_UART0_BAUD
+# define LM_CONSOLE_BITS CONFIG_UART0_BITS
+# define LM_CONSOLE_PARITY CONFIG_UART0_PARITY
+# define LM_CONSOLE_2STOP CONFIG_UART0_2STOP
+#elif defined(CONFIG_UART1_SERIAL_CONSOLE)
+# define LM_CONSOLE_BASE LM_UART1_BASE
+# define LM_CONSOLE_BAUD CONFIG_UART1_BAUD
+# define LM_CONSOLE_BITS CONFIG_UART1_BITS
+# define LM_CONSOLE_PARITY CONFIG_UART1_PARITY
+# define LM_CONSOLE_2STOP CONFIG_UART1_2STOP
+#elif defined(CONFIG_UART2_SERIAL_CONSOLE)
+# define LM_CONSOLE_BASE LM_UART2_BASE
+# define LM_CONSOLE_BAUD CONFIG_UART2_BAUD
+# define LM_CONSOLE_BITS CONFIG_UART2_BITS
+# define LM_CONSOLE_PARITY CONFIG_UART2_PARITY
+# define LM_CONSOLE_2STOP CONFIG_UART2_2STOP
+#elif defined(CONFIG_UART3_SERIAL_CONSOLE)
+# define LM_CONSOLE_BASE LM_UART3_BASE
+# define LM_CONSOLE_BAUD CONFIG_UART3_BAUD
+# define LM_CONSOLE_BITS CONFIG_UART3_BITS
+# define LM_CONSOLE_PARITY CONFIG_UART3_PARITY
+# define LM_CONSOLE_2STOP CONFIG_UART3_2STOP
+#elif defined(CONFIG_UART4_SERIAL_CONSOLE)
+# define LM_CONSOLE_BASE LM_UART4_BASE
+# define LM_CONSOLE_BAUD CONFIG_UART4_BAUD
+# define LM_CONSOLE_BITS CONFIG_UART4_BITS
+# define LM_CONSOLE_PARITY CONFIG_UART4_PARITY
+# define LM_CONSOLE_2STOP CONFIG_UART4_2STOP
+#elif defined(CONFIG_UART5_SERIAL_CONSOLE)
+# define LM_CONSOLE_BASE LM_UART5_BASE
+# define LM_CONSOLE_BAUD CONFIG_UART5_BAUD
+# define LM_CONSOLE_BITS CONFIG_UART5_BITS
+# define LM_CONSOLE_PARITY CONFIG_UART5_PARITY
+# define LM_CONSOLE_2STOP CONFIG_UART5_2STOP
+#elif defined(CONFIG_UART6_SERIAL_CONSOLE)
+# define LM_CONSOLE_BASE LM_UART6_BASE
+# define LM_CONSOLE_BAUD CONFIG_UART6_BAUD
+# define LM_CONSOLE_BITS CONFIG_UART6_BITS
+# define LM_CONSOLE_PARITY CONFIG_UART6_PARITY
+# define LM_CONSOLE_2STOP CONFIG_UART6_2STOP
+#elif defined(CONFIG_UART7_SERIAL_CONSOLE)
+# define LM_CONSOLE_BASE LM_UART7_BASE
+# define LM_CONSOLE_BAUD CONFIG_UART7_BAUD
+# define LM_CONSOLE_BITS CONFIG_UART7_BITS
+# define LM_CONSOLE_PARITY CONFIG_UART7_PARITY
+# define LM_CONSOLE_2STOP CONFIG_UART7_2STOP
+#else
+# error "No CONFIG_UARTn_SERIAL_CONSOLE Setting"
+#endif
+
+/* Get LCRH settings */
+
+#if LM_CONSOLE_BITS == 5
+# define UART_LCRH_NBITS UART_LCRH_WLEN_5BITS
+#elif LM_CONSOLE_BITS == 6
+# define UART_LCRH_NBITS UART_LCRH_WLEN_6BITS
+#elif LM_CONSOLE_BITS == 7
+# define UART_LCRH_NBITS UART_LCRH_WLEN_7BITS
+#elif LM_CONSOLE_BITS == 8
+# define UART_LCRH_NBITS UART_LCRH_WLEN_8BITS
+#else
+# error "Number of bits not supported"
+#endif
+
+#if LM_CONSOLE_PARITY == 0
+# define UART_LCRH_PARITY (0)
+#elif LM_CONSOLE_PARITY == 1
+# define UART_LCRH_PARITY UART_LCRH_PEN
+#elif LM_CONSOLE_PARITY == 2
+# define UART_LCRH_PARITY (UART_LCRH_PEN|UART_LCRH_EPS)
+#else
+# error "Invalid parity selection"
+#endif
+
+#if LM_CONSOLE_2STOP != 0
+# define UART_LCRH_NSTOP UART_LCRH_STP2
+#else
+# define UART_LCRH_NSTOP (0)
+#endif
+
+#define UART_LCRH_VALUE (UART_LCRH_NBITS|UART_LCRH_PARITY|UART_LCRH_NSTOP|UART_LCRH_FEN)
+
+/* Calculate BAUD rate from the SYS clock:
+ *
+ * "The baud-rate divisor is a 22-bit number consisting of a 16-bit integer and a 6-bit
+ * fractional part. The number formed by these two values is used by the baud-rate generator
+ * to determine the bit period. Having a fractional baud-rate divider allows the UART to
+ * generate all the standard baud rates.
+ *
+ * "The 16-bit integer is loaded through the UART Integer Baud-Rate Divisor (UARTIBRD)
+ * register ... and the 6-bit fractional part is loaded with the UART Fractional Baud-Rate
+ * Divisor (UARTFBRD) register... The baud-rate divisor (BRD) has the following relationship
+ * to the system clock (where BRDI is the integer part of the BRD and BRDF is the fractional
+ * part, separated by a decimal place.):
+ *
+ * "BRD = BRDI + BRDF = UARTSysClk / (16 * Baud Rate)
+ *
+ * "where UARTSysClk is the system clock connected to the UART. The 6-bit fractional number
+ * (that is to be loaded into the DIVFRAC bit field in the UARTFBRD register) can be calculated
+ * by taking the fractional part of the baud-rate divisor, multiplying it by 64, and adding 0.5
+ * to account for rounding errors:
+ *
+ * "UARTFBRD[DIVFRAC] = integer(BRDF * 64 + 0.5)
+ *
+ * "The UART generates an internal baud-rate reference clock at 16x the baud-rate (referred
+ * to as Baud16). This reference clock is divided by 16 to generate the transmit clock, and is
+ * used for error detection during receive operations.
+ *
+ * "Along with the UART Line Control, High Byte (UARTLCRH) register ..., the UARTIBRD and
+ * UARTFBRD registers form an internal 30-bit register. This internal register is only
+ * updated when a write operation to UARTLCRH is performed, so any changes to the baud-rate
+ * divisor must be followed by a write to the UARTLCRH register for the changes to take effect. ..."
+ */
+
+#define LM_BRDDEN (16 * LM_CONSOLE_BAUD)
+#define LM_BRDI (SYSCLK_FREQUENCY / LM_BRDDEN)
+#define LM_REMAINDER (SYSCLK_FREQUENCY - LM_BRDDEN * LM_BRDI)
+#define LM_DIVFRAC ((LM_REMAINDER * 64 + (LM_BRDDEN/2)) / LM_BRDDEN)
+
+/* For example: LM_CONSOLE_BAUD = 115,200, SYSCLK_FREQUENCY = 50,000,000:
+ *
+ * LM_BRDDEN = (16 * 115,200) = 1,843,200
+ * LM_BRDI = 50,000,000 / 1,843,200 = 27
+ * LM_REMAINDER = 50,000,000 - 1,843,200 * 27 = 233,600
+ * LM_DIVFRAC = (233,600 * 64 + 921,600) / 1,843,200 = 8
+ *
+ * Which should yied BAUD = 50,000,000 / (16 * (27 + 8/64)) = 115207.37
+ */
+
+/**************************************************************************
+ * 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
+ /* Wait until the TX FIFO is not full */
+
+ while ((getreg32(LM_CONSOLE_BASE+LM_UART_FR_OFFSET) & UART_FR_TXFF) != 0);
+
+ /* Then send the character */
+
+ putreg32((uint32_t)ch, LM_CONSOLE_BASE+LM_UART_DR_OFFSET);
+#endif
+}
+
+/**************************************************************************
+ * Name: up_lowsetup
+ *
+ * Description:
+ * This performs basic initialization of the UART used for the serial
+ * console. Its purpose is to get the console output availabe as soon
+ * as possible.
+ *
+ **************************************************************************/
+
+void up_lowsetup(void)
+{
+ uint32_t regval;
+#if defined(HAVE_SERIAL_CONSOLE) && !defined(CONFIG_SUPPRESS_UART_CONFIG)
+ uint32_t ctl;
+#endif
+
+ /* Enable the selected UARTs and configure GPIO pins needed by the
+ * the selected UARTs. NOTE: The serial driver later depends on
+ * this pin configuration -- whether or not a serial console is selected.
+ */
+
+#ifdef CONFIG_LM_UART0
+ regval = getreg32(LM_SYSCON_RCGC1);
+ regval |= SYSCON_RCGC1_UART0;
+ putreg32(regval, LM_SYSCON_RCGC1);
+
+ tiva_configgpio(GPIO_UART0_RX);
+ tiva_configgpio(GPIO_UART0_TX);
+#endif
+
+#ifdef CONFIG_LM_UART1
+ regval = getreg32(LM_SYSCON_RCGC1);
+ regval |= SYSCON_RCGC1_UART1;
+ putreg32(regval, LM_SYSCON_RCGC1);
+
+ tiva_configgpio(GPIO_UART1_RX);
+ tiva_configgpio(GPIO_UART1_TX);
+#endif
+
+#ifdef CONFIG_LM_UART2
+ regval = getreg32(LM_SYSCON_RCGC1);
+ regval |= SYSCON_RCGC1_UART2;
+ putreg32(regval, LM_SYSCON_RCGC1);
+
+ tiva_configgpio(GPIO_UART2_RX);
+ tiva_configgpio(GPIO_UART2_TX);
+#endif
+
+#ifdef CONFIG_LM_UART3
+ regval = getreg32(LM_SYSCON_RCGCUART);
+ regval |= SYSCON_RCGCUART_R3;
+ putreg32(regval, LM_SYSCON_RCGCUART);
+
+ tiva_configgpio(GPIO_UART3_RX);
+ tiva_configgpio(GPIO_UART3_TX);
+#endif
+
+#ifdef CONFIG_LM_UART4
+ regval = getreg32(LM_SYSCON_RCGCUART);
+ regval |= SYSCON_RCGCUART_R4;
+ putreg32(regval, LM_SYSCON_RCGCUART);
+
+ tiva_configgpio(GPIO_UART4_RX);
+ tiva_configgpio(GPIO_UART4_TX);
+#endif
+
+#ifdef CONFIG_LM_UART5
+ regval = getreg32(LM_SYSCON_RCGCUART);
+ regval |= SYSCON_RCGCUART_R5;
+ putreg32(regval, LM_SYSCON_RCGCUART);
+
+ tiva_configgpio(GPIO_UART5_RX);
+ tiva_configgpio(GPIO_UART5_TX);
+#endif
+
+#ifdef CONFIG_LM_UART6
+ regval = getreg32(LM_SYSCON_RCGCUART);
+ regval |= SYSCON_RCGCUART_R6;
+ putreg32(regval, LM_SYSCON_RCGCUART);
+
+ tiva_configgpio(GPIO_UART6_RX);
+ tiva_configgpio(GPIO_UART6_TX);
+#endif
+
+#ifdef CONFIG_LM_UART7
+ regval = getreg32(LM_SYSCON_RCGCUART);
+ regval |= SYSCON_RCGCUART_R7;
+ putreg32(regval, LM_SYSCON_RCGCUART);
+
+ tiva_configgpio(GPIO_UART7_RX);
+ tiva_configgpio(GPIO_UART7_TX);
+#endif
+
+ /* Enable the selected console device */
+
+#if defined(HAVE_SERIAL_CONSOLE) && !defined(CONFIG_SUPPRESS_UART_CONFIG)
+ /* Disable the UART by clearing the UARTEN bit in the UART CTL register */
+
+ ctl = getreg32(LM_CONSOLE_BASE+LM_UART_CTL_OFFSET);
+ ctl &= ~UART_CTL_UARTEN;
+ putreg32(ctl, LM_CONSOLE_BASE+LM_UART_CTL_OFFSET);
+
+ /* Write the integer portion of the BRD to the UART IBRD register */
+
+ putreg32(LM_BRDI, LM_CONSOLE_BASE+LM_UART_IBRD_OFFSET);
+
+ /* Write the fractional portion of the BRD to the UART FBRD register */
+
+ putreg32(LM_DIVFRAC, LM_CONSOLE_BASE+LM_UART_FBRD_OFFSET);
+
+ /* Write the desired serial parameters to the UART LCRH register */
+
+ putreg32(UART_LCRH_VALUE, LM_CONSOLE_BASE+LM_UART_LCRH_OFFSET);
+
+ /* Enable the UART by setting the UARTEN bit in the UART CTL register */
+
+ ctl |= (UART_CTL_UARTEN|UART_CTL_TXE|UART_CTL_RXE);
+ putreg32(ctl, LM_CONSOLE_BASE+LM_UART_CTL_OFFSET);
+#endif
+}