/****************************************************************************
* arch/arm/src/nuc1xx/nuc_lowputc.c
*
* Copyright (C) 2013 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 <assert.h>
#include <debug.h>
#include <arch/board/board.h>
#include "up_arch.h"
#include "chip.h"
#include "nuc_config.h"
#include "chip/chip/nuc_clk.h"
#include "chip/chip/nuc_uart.h"
#include "chip/nuc_gcr.h"
#include "nuc_lowputc.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Get the serial console UART configuration */
#ifdef HAVE_SERIAL_CONSOLE
# if defined(CONFIG_UART0_SERIAL_CONSOLE)
# define NUC_CONSOLE_BASE NUC_UART0_BASE
# define NUC_CONSOLE_DEPTH UART0_FIFO_DEPTH
# define NUC_CONSOLE_BAUD CONFIG_UART0_BAUD
# define NUC_CONSOLE_BITS CONFIG_UART0_BITS
# define NUC_CONSOLE_PARITY CONFIG_UART0_PARITY
# define NUC_CONSOLE_2STOP CONFIG_UART0_2STOP
# elif defined(CONFIG_UART1_SERIAL_CONSOLE)
# define NUC_CONSOLE_BASE NUC_UART1_BASE
# define NUC_CONSOLE_DEPTH UART1_FIFO_DEPTH
# define NUC_CONSOLE_BAUD CONFIG_UART1_BAUD
# define NUC_CONSOLE_BITS CONFIG_UART1_BITS
# define NUC_CONSOLE_PARITY CONFIG_UART1_PARITY
# define NUC_CONSOLE_2STOP CONFIG_UART1_2STOP
# elif defined(CONFIG_UART2_SERIAL_CONSOLE)
# define NUC_CONSOLE_BASE NUC_UART2_BASE
# define NUC_CONSOLE_DEPTH UART2_FIFO_DEPTH
# define NUC_CONSOLE_BAUD CONFIG_UART2_BAUD
# define NUC_CONSOLE_BITS CONFIG_UART2_BITS
# define NUC_CONSOLE_PARITY CONFIG_UART2_PARITY
# define NUC_CONSOLE_2STOP CONFIG_UART2_2STOP
# endif
#endif
/* Select either the external high speed crystal, the PLL output, or
* the internal high speed clock as the the UART clock source.
*/
#if defined(CONFIG_NUC_UARTCLK_XTALHI)
# define NUC_UART_CLK BOARD_XTALHI_FREQUENCY
#elif defined(CONFIG_NUC_UARTCLK_PLL)
# define NUC_UART_CLK BOARD_PLL_FOUT
#elif defined(CONFIG_NUC_UARTCLK_INTHI)
# define NUC_UART_CLK NUC_INTHI_FREQUENCY
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: nuc_console_ready
*
* Description:
* Wait until the console is ready to add another character to the TX
* FIFO.
*
*****************************************************************************/
#ifdef HAVE_SERIAL_CONSOLE
static inline void nuc_console_ready(void)
{
#if 1
/* Wait for the TX FIFO to be empty (excessive!) */
while ((getreg32(NUC_CONSOLE_BASE + NUC_UART_FSR_OFFSET) & UART_FSR_TX_EMPTY) == 0);
#else
uint32_t depth;
/* Wait until there is space in the TX FIFO */
do
{
register uint32_t regval = getreg32(NUC_CONSOLE_BASE + NUC_UART_FSR_OFFSET);
depth = (regval & UART_FSR_TX_POINTER_MASK) >> UART_FSR_TX_POINTER_SHIFT;
}
while (depth >= (NUC_CONSOLE_DEPTH-1));
#endif
}
#endif /* HAVE_SERIAL_CONSOLE */
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nuc_lowsetup
*
* Description:
* Called at the very beginning of _start. Performs low level initialization.
*
*****************************************************************************/
void nuc_lowsetup(void)
{
#ifdef HAVE_UART
uint32_t regval;
/* Configure UART GPIO pins.
*
* Basic UART0 TX/RX requires that GPIOB MFP bits 0 and 1 be set. If flow
* control is enabled, then GPIOB MFP bits 3 and 4 must also be set and ALT
* MFP bits 11, 13, and 14 must be cleared.
*/
#if defined(CONFIG_NUC_UART0) || defined(CONFIG_NUC_UART1)
regval = getreg32(NUC_GCR_GPB_MFP);
#ifdef CONFIG_NUC_UART0
#ifdef CONFIG_UART0_FLOW_CONTROL
regval |= (GCR_GPB_MFP0 | GCR_GPB_MFP1 | GCR_GPB_MFP2| GCR_GPB_MFP3);
#else
regval |= (GCR_GPB_MFP0 | GCR_GPB_MFP1);
#endif
#endif /* CONFIG_NUC_UART0 */
/* Basic UART1 TX/RX requires that GPIOB MFP bits 4 and 5 be set. If flow
* control is enabled, then GPIOB MFP bits 6 and 7 must also be set and ALT
* MFP bit 11 must be cleared.
*/
#ifdef CONFIG_NUC_UART1
#ifdef CONFIG_UART1_FLOW_CONTROL
regval |= (GCR_GPB_MFP4 | GCR_GPB_MFP5 | GCR_GPB_MFP6| GCR_GPB_MFP7)
#else
regval |= (GCR_GPB_MFP4 | GCR_GPB_MFP5);
#endif
#endif /* CONFIG_NUC_UART1 */
putreg32(regval, NUC_GCR_GPB_MFP);
#if defined(CONFIG_UART0_FLOW_CONTROL) || defined(CONFIG_UART1_FLOW_CONTROL)
regval = getreg32(NUC_GCR_ALT_MFP);
regval &= ~GCR_ALT_MFP_EBI_EN;
#ifdef CONFIG_UART0_FLOW_CONTROL
regval &= ~(GCR_ALT_MFP_EBI_NWRL_EN | GCR_ALT_MFP_EBI_NWRH_WN);
#endif
putreg32(NUC_GCR_ALT_MFP);
#endif /* CONFIG_UART0_FLOW_CONTROL || CONFIG_UART1_FLOW_CONTROL */
#endif /* CONFIG_NUC_UART0 || CONFIG_NUC_UART1 */
/* UART1 TX/RX support requires that GPIOD bits 14 and 15 be set. UART2
* does not support flow control.
*/
#ifdef CONFIG_NUC_UART2
regval = getreg32(NUC_GCR_GPD_MFP);
regval |= (GCR_GPD_MFP14 | GCR_GPD_MFP15);
putreg32(regval, NUC_GCR_GPD_MFP);
#endif /* CONFIG_NUC_UART2 */
/* Reset the UART peripheral(s) */
regval = getreg32(NUC_GCR_IPRSTC2);
#ifdef CONFIG_NUC_UART0
regval |= GCR_IPRSTC2_UART0_RST;
putreg32(regval, NUC_GCR_IPRSTC2);
regval &= ~GCR_IPRSTC2_UART0_RST;
putreg32(regval, NUC_GCR_IPRSTC2);
#endif
#ifdef CONFIG_NUC_UART1
regval |= GCR_IPRSTC2_UART1_RST;
putreg32(regval, NUC_GCR_IPRSTC2);
regval &= ~GCR_IPRSTC2_UART1_RST;
putreg32(regval, NUC_GCR_IPRSTC2);
#endif
#ifdef CONFIG_NUC_UART2
regval |= GCR_IPRSTC2_UART2_RST;
putreg32(regval, NUC_GCR_IPRSTC2);
regval &= ~GCR_IPRSTC2_UART2_RST;
putreg32(regval, NUC_GCR_IPRSTC2);
#endif
/* Configure the UART clock source. Set the UART clock source to either
* the external high speed crystal (CLKSEL1 reset value), the PLL output,
* or the internal high speed clock.
*/
regval = getreg32(NUC_CLK_CLKSEL1);
regval &= ~CLK_CLKSEL1_UART_S_MASK;
#if defined(CONFIG_NUC_UARTCLK_XTALHI)
regval |= CLK_CLKSEL1_UART_S_XTALHI;
#elif defined(CONFIG_NUC_UARTCLK_PLL)
regval |= CLK_CLKSEL1_UART_S_PLL;
#elif defined(CONFIG_NUC_UARTCLK_INTHI)
regval |= CLK_CLKSEL1_UART_S_INTHI;
#endif
putreg32(regval, NUC_CLK_CLKSEL1);
/* Enable UART clocking for the selected UARTs */
regval = getreg32(NUC_CLK_APBCLK);
regval &= ~(CLK_APBCLK_UART0_EN | CLK_APBCLK_UART1_EN | CLK_APBCLK_UART2_EN);
#ifdef CONFIG_NUC_UART0
regval |= CLK_APBCLK_UART0_EN;
#endif
#ifdef CONFIG_NUC_UART1
regval |= CLK_APBCLK_UART1_EN;
#endif
#ifdef CONFIG_NUC_UART2
regval |= CLK_APBCLK_UART2_EN;
#endif
putreg32(regval, NUC_CLK_APBCLK);
/* Configure the console UART */
#ifdef HAVE_SERIAL_CONSOLE
/* Reset the TX FIFO */
regval = getreg32(NUC_CONSOLE_BASE + NUC_UART_FCR_OFFSET);
regval &= ~(UART_FCR_TFR | UART_FCR_RFR);
putreg32(regval | UART_FCR_TFR, NUC_CONSOLE_BASE + NUC_UART_FCR_OFFSET);
/* Reset the RX FIFO */
putreg32(regval | UART_FCR_RFR, NUC_CONSOLE_BASE + NUC_UART_FCR_OFFSET);
/* Set Rx Trigger Level */
regval &= ~UART_FCR_RFITL_MASK;
regval |= UART_FCR_RFITL_4;
putreg32(regval, NUC_CONSOLE_BASE + NUC_UART_FCR_OFFSET);
/* Set Parity & Data bits and Stop bits */
regval = 0;
#if NUC_CONSOLE_BITS == 5
regval |= UART_LCR_WLS_5;
#elif NUC_CONSOLE_BITS == 6
regval |= UART_LCR_WLS_6;
#elif NUC_CONSOLE_BITS == 7
regval |= UART_LCR_WLS_7;
#elif NUC_CONSOLE_BITS == 8
regval |= UART_LCR_WLS_8;
#else
error "Unknown console UART data width"
#endif
#if NUC_CONSOLE_PARITY == 1
regval |= UART_LCR_PBE;
#elif NUC_CONSOLE_PARITY == 2
regval |= (UART_LCR_PBE | UART_LCR_EPE);
#endif
#if NUC_CONSOLE_2STOP != 0
regval |= UART_LCR_NSB;
#endif
putreg32(regval, NUC_CONSOLE_BASE + NUC_UART_LCR_OFFSET);
/* Set Time-Out values */
regval = UART_TOR_TOIC(40) | UART_TOR_DLY(0);
putreg32(regval, NUC_CONSOLE_BASE + NUC_UART_TOR_OFFSET);
/* Set the baud */
nuc_setbaud(NUC_CONSOLE_BASE, NUC_CONSOLE_BAUD);
#endif /* HAVE_SERIAL_CONSOLE */
#endif /* HAVE_UART */
}
/****************************************************************************
* Name: nuc_lowputc
*
* Description:
* Output one character to the UART using a simple polling method.
*
*****************************************************************************/
void nuc_lowputc(uint32_t ch)
{
#ifdef HAVE_SERIAL_CONSOLE
/* Wait for the TX FIFO to become available */
nuc_console_ready();
/* Then write the character to to the TX FIFO */
putreg32(ch, NUC_CONSOLE_BASE + NUC_UART_THR_OFFSET);
#endif /* HAVE_SERIAL_CONSOLE */
}
/****************************************************************************
* Name: nuc_setbaud
*
* Description:
* Set the BAUD divxisor for the selected UART
*
* Mode DIV_X_EN DIV_X_ONE Divider X BRD (Baud rate equation)
* -------------------------------------------------------------
* 0 0 0 B A UART_CLK / [16 * (A+2)]
* 1 1 0 B A UART_CLK / [(B+1) * (A+2)] , B must >= 8
* 2 1 1 Don't care A UART_CLK / (A+2), A must >=3
*
* Here we assume that the default clock source for the UART modules is
* the external high speed crystal.
*
*****************************************************************************/
#ifdef HAVE_UART
void nuc_setbaud(uintptr_t base, uint32_t baud)
{
uint32_t regval;
uint32_t clksperbit;
uint32_t brd;
uint32_t divx;
regval = getreg32(base + NUC_UART_BAUD_OFFSET);
/* Mode 0: Source Clock mod 16 < 3 => Using Divider X = 16 */
clksperbit = (NUC_UART_CLK + (baud >> 1)) / baud;
if ((clksperbit & 15) < 3)
{
regval &= ~(UART_BAUD_DIV_X_ONE | UART_BAUD_DIV_X_EN);
brd = (clksperbit >> 4) - 2;
}
/* Source Clock mod 16 >3 => Up 5% Error BaudRate */
else
{
/* Mode 2: Try to Set Divider X = 1 */
regval |= (UART_BAUD_DIV_X_ONE | UART_BAUD_DIV_X_EN);
brd = clksperbit - 2;
/* Check if the divxider exceeds the range */
if (brd > 0xffff)
{
/* Mode 1: Try to Set Divider X up 10 */
regval &= ~UART_BAUD_DIV_X_ONE;
for (divx = 8; divx < 16; divx++)
{
brd = clksperbit % (divx + 1);
if (brd < 3)
{
regval &= ~UART_BAUD_DIVIDER_X_MASK;
regval |= UART_BAUD_DIVIDER_X(divx);
brd -= 2;
break;
}
}
}
}
regval &= ~UART_BAUD_BRD_MASK;
regval |= UART_BAUD_BRD(brd);
putreg32(regval, base + NUC_UART_BAUD_OFFSET);
}
#endif /* HAVE_UART */
