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/************************************************************************************
* include/nuttx/serial/uart_16550.h
* Serial driver for 16550 UART
*
* Copyright (C) 2011-2012 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.
*
************************************************************************************/
#ifndef __INCLUDE_NUTTX_SERIAL_UART_16550_H
#define __INCLUDE_NUTTX_SERIAL_UART_16550_H
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#ifdef CONFIG_16550_UART
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
/* CONFIGURATION ********************************************************************/
/* Are any UARTs enabled? */
#undef HAVE_UART
#if defined(CONFIG_16550_UART0) || defined(CONFIG_16550_UART1) || \
defined(CONFIG_16550_UART2) || defined(CONFIG_16550_UART3)
# define HAVE_UART 1
#endif
/* We need to be told the address increment between registers and the register bit
* width.
*/
#ifndef CONFIG_16550_REGINCR
# error "CONFIG_16550_REGINCR not defined"
#endif
#if CONFIG_16550_REGINCR != 1 && CONFIG_16550_REGINCR != 2 && CONFIG_16550_REGINCR != 4
# error "CONFIG_16550_REGINCR not supported"
#endif
#ifndef CONFIG_16550_REGWIDTH
# error "CONFIG_16550_REGWIDTH not defined"
#endif
#if CONFIG_16550_REGWIDTH != 8 && CONFIG_16550_REGWIDTH != 16 && CONFIG_16550_REGWIDTH != 32
# error "CONFIG_16550_REGWIDTH not supported"
#endif
#ifndef CONFIG_16550_ADDRWIDTH
# error "CONFIG_16550_ADDRWIDTH not defined"
#endif
#if CONFIG_16550_ADDRWIDTH != 8 && CONFIG_16550_ADDRWIDTH != 16 && CONFIG_16550_ADDRWIDTH != 32
# error "CONFIG_16550_ADDRWIDTH not supported"
#endif
/* If a UART is enabled, then its base address, clock, and IRQ must also be provided */
#ifdef CONFIG_16550_UART0
# ifndef CONFIG_16550_UART0_BASE
# error "CONFIG_16550_UART0_BASE not provided"
# undef CONFIG_16550_UART0
# endif
# ifndef CONFIG_16550_UART0_CLOCK
# error "CONFIG_16550_UART0_CLOCK not provided"
# undef CONFIG_16550_UART0
# endif
# ifndef CONFIG_16550_UART0_IRQ
# error "CONFIG_16550_UART0_IRQ not provided"
# undef CONFIG_16550_UART0
# endif
#endif
#ifdef CONFIG_16550_UART1
# ifndef CONFIG_16550_UART1_BASE
# error "CONFIG_16550_UART1_BASE not provided"
# undef CONFIG_16550_UART1
# endif
# ifndef CONFIG_16550_UART1_CLOCK
# error "CONFIG_16550_UART1_CLOCK not provided"
# undef CONFIG_16550_UART1
# endif
# ifndef CONFIG_16550_UART1_IRQ
# error "CONFIG_16550_UART1_IRQ not provided"
# undef CONFIG_16550_UART1
# endif
#endif
#ifdef CONFIG_16550_UART2
# ifndef CONFIG_16550_UART2_BASE
# error "CONFIG_16550_UART2_BASE not provided"
# undef CONFIG_16550_UART2
# endif
# ifndef CONFIG_16550_UART2_CLOCK
# error "CONFIG_16550_UART2_CLOCK not provided"
# undef CONFIG_16550_UART2
# endif
# ifndef CONFIG_16550_UART2_IRQ
# error "CONFIG_16550_UART2_IRQ not provided"
# undef CONFIG_16550_UART2
# endif
#endif
#ifdef CONFIG_16550_UART3
# ifndef CONFIG_16550_UART3_BASE
# error "CONFIG_16550_UART3_BASE not provided"
# undef CONFIG_16550_UART3
# endif
# ifndef CONFIG_16550_UART3_CLOCK
# error "CONFIG_16550_UART3_CLOCK not provided"
# undef CONFIG_16550_UART3
# endif
# ifndef CONFIG_16550_UART3_IRQ
# error "CONFIG_16550_UART3_IRQ not provided"
# undef CONFIG_16550_UART3
# endif
#endif
/* Is there a serial console? There should be at most one defined. It could be on
* any UARTn, n=0,1,2,3
*/
#if defined(CONFIG_UART0_SERIAL_CONSOLE) && defined(CONFIG_16550_UART0)
# undef CONFIG_UART1_SERIAL_CONSOLE
# undef CONFIG_UART2_SERIAL_CONSOLE
# undef CONFIG_UART3_SERIAL_CONSOLE
# define HAVE_16550_CONSOLE 1
#elif defined(CONFIG_UART1_SERIAL_CONSOLE) && defined(CONFIG_16550_UART1)
# undef CONFIG_UART0_SERIAL_CONSOLE
# undef CONFIG_UART2_SERIAL_CONSOLE
# undef CONFIG_UART3_SERIAL_CONSOLE
# define HAVE_16550_CONSOLE 1
#elif defined(CONFIG_UART2_SERIAL_CONSOLE) && defined(CONFIG_16550_UART2)
# undef CONFIG_UART0_SERIAL_CONSOLE
# undef CONFIG_UART1_SERIAL_CONSOLE
# undef CONFIG_UART3_SERIAL_CONSOLE
# define HAVE_16550_CONSOLE 1
#elif defined(CONFIG_UART3_SERIAL_CONSOLE) && defined(CONFIG_16550_UART3)
# undef CONFIG_UART0_SERIAL_CONSOLE
# undef CONFIG_UART1_SERIAL_CONSOLE
# undef CONFIG_UART2_SERIAL_CONSOLE
# define HAVE_16550_CONSOLE 1
#else
# undef CONFIG_UART0_SERIAL_CONSOLE
# undef CONFIG_UART1_SERIAL_CONSOLE
# undef CONFIG_UART2_SERIAL_CONSOLE
# undef CONFIG_UART3_SERIAL_CONSOLE
# undef HAVE_16550_CONSOLE
#endif
/* Register offsets *****************************************************************/
#define UART_RBR_INCR 0 /* (DLAB =0) Receiver Buffer Register */
#define UART_THR_INCR 0 /* (DLAB =0) Transmit Holding Register */
#define UART_DLL_INCR 0 /* (DLAB =1) Divisor Latch LSB */
#define UART_DLM_INCR 1 /* (DLAB =1) Divisor Latch MSB */
#define UART_IER_INCR 1 /* (DLAB =0) Interrupt Enable Register */
#define UART_IIR_INCR 2 /* Interrupt ID Register */
#define UART_FCR_INCR 2 /* FIFO Control Register */
#define UART_LCR_INCR 3 /* Line Control Register */
#define UART_MCR_INCR 4 /* Modem Control Register */
#define UART_LSR_INCR 5 /* Line Status Register */
#define UART_MSR_INCR 6 /* Modem Status Register */
#define UART_SCR_INCR 7 /* Scratch Pad Register */
#define UART_RBR_OFFSET (CONFIG_16550_REGINCR*UART_RBR_INCR)
#define UART_THR_OFFSET (CONFIG_16550_REGINCR*UART_THR_INCR)
#define UART_DLL_OFFSET (CONFIG_16550_REGINCR*UART_DLL_INCR)
#define UART_DLM_OFFSET (CONFIG_16550_REGINCR*UART_DLM_INCR)
#define UART_IER_OFFSET (CONFIG_16550_REGINCR*UART_IER_INCR)
#define UART_IIR_OFFSET (CONFIG_16550_REGINCR*UART_IIR_INCR)
#define UART_FCR_OFFSET (CONFIG_16550_REGINCR*UART_FCR_INCR)
#define UART_LCR_OFFSET (CONFIG_16550_REGINCR*UART_LCR_INCR)
#define UART_MCR_OFFSET (CONFIG_16550_REGINCR*UART_MCR_INCR)
#define UART_LSR_OFFSET (CONFIG_16550_REGINCR*UART_LSR_INCR)
#define UART_MSR_OFFSET (CONFIG_16550_REGINCR*UART_MSR_INCR)
#define UART_SCR_OFFSET (CONFIG_16550_REGINCR*UART_SCR_INCR)
/* Register bit definitions *********************************************************/
/* RBR (DLAB =0) Receiver Buffer Register */
#define UART_RBR_MASK (0xff) /* Bits 0-7: Oldest received byte in RX FIFO */
/* Bits 8-31: Reserved */
/* THR (DLAB =0) Transmit Holding Register */
#define UART_THR_MASK (0xff) /* Bits 0-7: Adds byte to TX FIFO */
/* Bits 8-31: Reserved */
/* DLL (DLAB =1) Divisor Latch LSB */
#define UART_DLL_MASK (0xff) /* Bits 0-7: DLL */
/* Bits 8-31: Reserved */
/* DLM (DLAB =1) Divisor Latch MSB */
#define UART_DLM_MASK (0xff) /* Bits 0-7: DLM */
/* Bits 8-31: Reserved */
/* IER (DLAB =0) Interrupt Enable Register */
#define UART_IER_ERBFI (1 << 0) /* Bit 0: Enable received data available interrupt */
#define UART_IER_ETBEI (1 << 1) /* Bit 1: Enable THR empty interrupt */
#define UART_IER_ELSI (1 << 2) /* Bit 2: Enable receiver line status interrupt */
#define UART_IER_EDSSI (1 << 3) /* Bit 3: Enable MODEM status interrupt */
/* Bits 4-7: Reserved */
#define UART_IER_ALLIE (0x0f)
/* IIR Interrupt ID Register */
#define UART_IIR_INTSTATUS (1 << 0) /* Bit 0: Interrupt status (active low) */
#define UART_IIR_INTID_SHIFT (1) /* Bits 1-3: Interrupt identification */
#define UART_IIR_INTID_MASK (7 << UART_IIR_INTID_SHIFT)
# define UART_IIR_INTID_MSI (0 << UART_IIR_INTID_SHIFT) /* Modem Status */
# define UART_IIR_INTID_THRE (1 << UART_IIR_INTID_SHIFT) /* THR Empty Interrupt */
# define UART_IIR_INTID_RDA (2 << UART_IIR_INTID_SHIFT) /* Receive Data Available (RDA) */
# define UART_IIR_INTID_RLS (3 << UART_IIR_INTID_SHIFT) /* Receiver Line Status (RLS) */
# define UART_IIR_INTID_CTI (6 << UART_IIR_INTID_SHIFT) /* Character Time-out Indicator (CTI) */
/* Bits 4-5: Reserved */
#define UART_IIR_FIFOEN_SHIFT (6) /* Bits 6-7: RCVR FIFO interrupt */
#define UART_IIR_FIFOEN_MASK (3 << UART_IIR_FIFOEN_SHIFT)
/* FCR FIFO Control Register */
#define UART_FCR_FIFOEN (1 << 0) /* Bit 0: Enable FIFOs */
#define UART_FCR_RXRST (1 << 1) /* Bit 1: RX FIFO Reset */
#define UART_FCR_TXRST (1 << 2) /* Bit 2: TX FIFO Reset */
#define UART_FCR_DMAMODE (1 << 3) /* Bit 3: DMA Mode Select */
/* Bits 4-5: Reserved */
#define UART_FCR_RXTRIGGER_SHIFT (6) /* Bits 6-7: RX Trigger Level */
#define UART_FCR_RXTRIGGER_MASK (3 << UART_FCR_RXTRIGGER_SHIFT)
# define UART_FCR_RXTRIGGER_1 (0 << UART_FCR_RXTRIGGER_SHIFT) /* Trigger level 0 (1 character) */
# define UART_FCR_RXTRIGGER_4 (1 << UART_FCR_RXTRIGGER_SHIFT) /* Trigger level 1 (4 characters) */
# define UART_FCR_RXTRIGGER_8 (2 << UART_FCR_RXTRIGGER_SHIFT) /* Trigger level 2 (8 characters) */
# define UART_FCR_RXTRIGGER_14 (3 << UART_FCR_RXTRIGGER_SHIFT) /* Trigger level 3 (14 characters) */
/* LCR Line Control Register */
#define UART_LCR_WLS_SHIFT (0) /* Bit 0-1: Word Length Select */
#define UART_LCR_WLS_MASK (3 << UART_LCR_WLS_SHIFT)
# define UART_LCR_WLS_5BIT (0 << UART_LCR_WLS_SHIFT)
# define UART_LCR_WLS_6BIT (1 << UART_LCR_WLS_SHIFT)
# define UART_LCR_WLS_7BIT (2 << UART_LCR_WLS_SHIFT)
# define UART_LCR_WLS_8BIT (3 << UART_LCR_WLS_SHIFT)
#define UART_LCR_STB (1 << 2) /* Bit 2: Number of Stop Bits */
#define UART_LCR_PEN (1 << 3) /* Bit 3: Parity Enable */
#define UART_LCR_EPS (1 << 4) /* Bit 4: Even Parity Select */
#define UART_LCR_STICKY (1 << 5) /* Bit 5: Stick Parity */
#define UART_LCR_BRK (1 << 6) /* Bit 6: Break Control */
#define UART_LCR_DLAB (1 << 7) /* Bit 7: Divisor Latch Access Bit (DLAB) */
/* MCR Modem Control Register */
#define UART_MCR_DTR (1 << 0) /* Bit 0: DTR Control Source for DTR output */
#define UART_MCR_RTS (1 << 1) /* Bit 1: Control Source for RTS output */
#define UART_MCR_OUT1 (1 << 2) /* Bit 2: Auxiliary user-defined output 1 */
#define UART_MCR_OUT2 (1 << 3) /* Bit 3: Auxiliary user-defined output 2 */
#define UART_MCR_LPBK (1 << 4) /* Bit 4: Loopback Mode Select */
/* Bit 5-7: Reserved */
/* LSR Line Status Register */
#define UART_LSR_DR (1 << 0) /* Bit 0: Data Ready */
#define UART_LSR_OE (1 << 1) /* Bit 1: Overrun Error */
#define UART_LSR_PE (1 << 2) /* Bit 2: Parity Error */
#define UART_LSR_FE (1 << 3) /* Bit 3: Framing Error */
#define UART_LSR_BI (1 << 4) /* Bit 4: Break Interrupt */
#define UART_LSR_THRE (1 << 5) /* Bit 5: Transmitter Holding Register Empty */
#define UART_LSR_TEMT (1 << 6) /* Bit 6: Transmitter Empty */
#define UART_LSR_RXFE (1 << 7) /* Bit 7: Error in RX FIFO (RXFE) */
/* SCR Scratch Pad Register */
#define UART_SCR_MASK (0xff) /* Bits 0-7: SCR data */
/************************************************************************************
* Public Types
************************************************************************************/
#if CONFIG_16550_REGWIDTH == 8
typedef uint8_t uart_datawidth_t;
#elif CONFIG_16550_REGWIDTH == 16
typedef uint16_t uart_datawidth_t;
#elif CONFIG_16550_REGWIDTH == 32
typedef uint32_t uart_datawidth_t;
#endif
#if CONFIG_16550_ADDRWIDTH == 8
typedef uint8_t uart_addrwidth_t;
#elif CONFIG_16550_ADDRWIDTH == 16
typedef uint16_t uart_addrwidth_t;
#elif CONFIG_16550_ADDRWIDTH == 32
typedef uint32_t uart_addrwidth_t;
#endif
/************************************************************************************
* Public Data
************************************************************************************/
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: uart_getreg(), uart_putreg()
*
* Description:
* These functions must be provided by the processor-specific code in order to
* correctly access 16550 registers
*
************************************************************************************/
extern uart_datawidth_t uart_getreg(uart_addrwidth_t base, unsigned int offset);
extern void uart_putreg(uart_addrwidth_t base, unsigned int offset, uart_datawidth_t value);
#endif /* CONFIG_UART_16550 */
#endif /* __INCLUDE_NUTTX_SERIAL_UART_16550_H */
|