source: rtems/bsps/powerpc/include/bsp/uart.h

/*
 * This software is Copyright (C) 1998 by T.sqware - all rights limited
 * It is provided in to the public domain "as is", can be freely modified
 * as far as this copyight notice is kept unchanged, but does not imply
 * an endorsement by T.sqware of the product in which it is included.
 */

#ifndef _BSPUART_H
#define _BSPUART_H

#include <bsp/irq.h>

#include <sys/ioctl.h>
#include <rtems/libio.h>

void     BSP_uart_init(int uart, int baud, int hwFlow);
void     BSP_uart_set_baud(int uart, int baud);
void     BSP_uart_intr_ctrl(int uart, int cmd);
void     BSP_uart_throttle(int uart);
void     BSP_uart_unthrottle(int uart);
int      BSP_uart_polled_status(int uart);
void     BSP_uart_polled_write(int uart, int val);
int      BSP_uart_polled_read(int uart);
void     BSP_uart_termios_set(int uart, void *ttyp);
ssize_t  BSP_uart_termios_write_com(int minor, const char *buf, size_t len);
int      BSP_uart_termios_read_com (int minor);
void     BSP_uart_termios_isr_com1(void *unused);
void     BSP_uart_termios_isr_com2(void *unused);
void     BSP_uart_dbgisr_com1(void);
void     BSP_uart_dbgisr_com2(void);
int      BSP_uart_install_isr(int uart, rtems_irq_hdl handler);
int      BSP_uart_remove_isr(int uart, rtems_irq_hdl handler);
ssize_t BSP_uart_termios_write_polled(int minor, const char *buf, size_t len);
int      BSP_uart_get_break_cb(int uart, rtems_libio_ioctl_args_t *arg);
int      BSP_uart_set_break_cb(int uart, rtems_libio_ioctl_args_t *arg);

extern unsigned BSP_poll_char_via_serial(void);
extern void BSP_output_char_via_serial(const char val);
extern int BSPConsolePort;
extern int BSPBaseBaud;

/* Special IOCTLS to install a lowlevel 'BREAK' handler */

/* pass a BSP_UartBreakCb pointer to ioctl when retrieving
 * or installing break callback
 */
typedef void (*BSP_UartBreakCbProc)(
  int uartMinor,
  unsigned uartRBRLSRStatus,
  void  *termiosPrivatePtr,
  void  *private
);

typedef struct BSP_UartBreakCbRec_ {
  BSP_UartBreakCbProc  handler; /* NOTE: handler runs in INTERRUPT CONTEXT */
  void     *private; /* closure pointer which is passed to the callback  */
} BSP_UartBreakCbRec, *BSP_UartBreakCb;

#define BIOCGETBREAKCB _IOR('b',1,sizeof(BSP_UartBreakCbRec))
#define BIOCSETBREAKCB _IOW('b',2,sizeof(BSP_UartBreakCbRec))

/*
 * Command values for BSP_uart_intr_ctrl(),
 * values are strange in order to catch errors
 * with assert
 */
#define BSP_UART_INTR_CTRL_DISABLE  (0)
#define BSP_UART_INTR_CTRL_GDB      (0xaa) /* RX only */
#define BSP_UART_INTR_CTRL_ENABLE   (0xbb) /* Normal operations */
#define BSP_UART_INTR_CTRL_TERMIOS  (0xcc) /* RX & line status */

/* Return values for uart_polled_status() */
#define BSP_UART_STATUS_ERROR    (-1) /* No character */
#define BSP_UART_STATUS_NOCHAR   (0)  /* No character */
#define BSP_UART_STATUS_CHAR     (1)  /* Character present */
#define BSP_UART_STATUS_BREAK    (2)  /* Break point is detected */

/* PC UART definitions */
#define BSP_UART_COM1            (0)
#define BSP_UART_COM2            (1)

/*
 * Offsets from base
 */

/* DLAB 0 */
#define RBR  (0)    /* Rx Buffer Register (read) */
#define THR  (0)    /* Tx Buffer Register (write) */
#define IER  (1)    /* Interrupt Enable Register */

/* DLAB X */
#define IIR  (2)    /* Interrupt Ident Register (read) */
#define FCR  (2)    /* FIFO Control Register (write) */
#define LCR  (3)    /* Line Control Register */
#define MCR  (4)    /* Modem Control Register */
#define LSR  (5)    /* Line Status Register */
#define MSR  (6)    /* Modem Status  Register */
#define SCR  (7)    /* Scratch register */

/* DLAB 1 */
#define DLL  (0)    /* Divisor Latch, LSB */
#define DLM  (1)    /* Divisor Latch, MSB */
#define AFR  (2)    /* Alternate Function register */

/*
 * Interrupt source definition via IIR
 */
#define MODEM_STATUS                       0
#define NO_MORE_INTR                       1
#define TRANSMITTER_HODING_REGISTER_EMPTY  2
#define RECEIVER_DATA_AVAIL                4
#define RECEIVER_ERROR                     6
#define CHARACTER_TIMEOUT_INDICATION      12

/*
 * Bits definition of IER
 */
#define RECEIVE_ENABLE          0x1
#define TRANSMIT_ENABLE         0x2
#define RECEIVER_LINE_ST_ENABLE 0x4
#define MODEM_ENABLE            0x8
#define INTERRUPT_DISABLE       0x0

/*
 * Bits definition of the Line Status Register (LSR)
 */
#define DR     0x01 /* Data Ready */
#define OE     0x02 /* Overrun Error */
#define PE     0x04 /* Parity Error */
#define FE     0x08 /* Framing Error */
#define BI     0x10 /* Break Interrupt */
#define THRE   0x20 /* Transmitter Holding Register Empty */
#define TEMT   0x40 /* Transmitter Empty */
#define ERFIFO 0x80 /* Error receive Fifo */

/*
 * Bits definition of the MODEM Control Register (MCR)
 */
#define DTR   0x01 /* Data Terminal Ready */
#define RTS   0x02 /* Request To Send */
#define OUT_1 0x04 /* Output 1, (reserved on COMPAQ I/O Board) */
#define OUT_2 0x08 /* Output 2, Enable Asynchronous Port Interrupts */
#define LB    0x10 /* Enable Internal Loop Back */

/*
 * Bits definition of the Line Control Register (LCR)
 */
#define CHR_5_BITS 0
#define CHR_6_BITS 1
#define CHR_7_BITS 2
#define CHR_8_BITS 3

#define WL   0x03 /* Word length mask */
#define STB  0x04 /* 1 Stop Bit, otherwise 2 Stop Bits */
#define PEN  0x08 /* Parity Enabled */
#define EPS  0x10 /* Even Parity Select, otherwise Odd */
#define SP   0x20 /* Stick Parity */
#define BCB  0x40 /* Break Control Bit */
#define DLAB 0x80 /* Enable Divisor Latch Access */

/*
 * Bits definition of the MODEM Status Register (MSR)
 */
#define DCTS 0x01 /* Delta Clear To Send */
#define DDSR 0x02 /* Delta Data Set Ready */
#define TERI 0x04 /* Trailing Edge Ring Indicator */
#define DDCD 0x08 /* Delta Carrier Detect Indicator */
#define CTS  0x10 /* Clear To Send (when loop back is active) */
#define DSR  0x20 /* Data Set Ready (when loop back is active) */
#define RI   0x40 /* Ring Indicator (when loop back is active) */
#define DCD  0x80 /* Data Carrier Detect (when loop back is active) */

/*
 * Bits definition of the FIFO Control Register : WD16C552 or NS16550
 */

#define FIFO_CTRL  0x01 /* Set to 1 permit access to other bits */
#define FIFO_EN    0x01 /* Enable the FIFO */
#define XMIT_RESET 0x02 /* Transmit FIFO Reset */
#define RCV_RESET  0x04 /* Receive FIFO Reset */
#define FCR3       0x08 /* do not understand manual! */

#define RECEIVE_FIFO_TRIGGER1  0x00 /* trigger RX interrupt after 1 byte  */
#define RECEIVE_FIFO_TRIGGER4  0x40 /* trigger RX interrupt after 4 bytes  */
#define RECEIVE_FIFO_TRIGGER8  0x80 /* trigger RX interrupt after 8 bytes  */
#define RECEIVE_FIFO_TRIGGER12 0xc0 /* trigger RX interrupt after 12 bytes */
#define TRIG_LEVEL             0xc0 /* Mask for the trigger level   */

#endif /* _BSPUART_H */