/*
* This file contains the efi68k console IO package.
*
* COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
* On-Line Applications Research Corporation (OAR).
* All rights assigned to U.S. Government, 1994.
*
* This material may be reproduced by or for the U.S. Government pursuant
* to the copyright license under the clause at DFARS 252.227-7013. This
* notice must appear in all copies of this file and its derivatives.
*
* $Id$
*/
#include <stdlib.h>
#include <bsp.h>
#include <rtems/libio.h>
#define BAUD 38400
#define CLK_FREQ 8000000.0
/* BUFFER_LENGTH must be 2^n for n=1, 2, 3, .... */
#define BUFFER_LENGTH 256
#define RTS_STOP_SIZE BUFFER_LENGTH-64
#define RTS_START_SIZE 16
char xmt_buf[BUFFER_LENGTH];
char rcv_buf[BUFFER_LENGTH];
/* in: last entry into the buffer; always on a valid character */
/* out: points to the next character to be pull from the buffer */
/* in+1=out => buffer empty */
/* in+2=out => buffer full */
struct UART_buf {
char *offset;
char *in;
char *out;
};
static volatile struct UART_buf xmt = { xmt_buf, (char *)0, (char *)1};
static volatile struct UART_buf rcv = { rcv_buf, (char *)0, (char *)1};
static volatile char _debug_flag = 0;
static volatile char _tx_stop = 0;
/* _catchUARTint is the interrupt front-end */
extern void _catchUARTint();
asm(" .text
.align 2
.globl _catchUARTint
_catchUARTint:
lea %sp@(4),%sp /* pop return address */
moveml %d0-%d7/%a0-%a6,%sp@- /* save registers */
jbsr uart_interrupt
moveml %sp@+,%d0-%d7/%a0-%a6
rte
");
/* _fake_trap_1 will continue the UART interrupt (%sr *still*
UART_ISR_LEVEL) as a trap #1 to enter the debugger */
asm(" .text
.align 2
_fake_trap_1:
unlk %a6 /* clear interrupt frame */
lea %sp@(4),%sp /* remove jbsr instruction */
moveml %sp@+,%d0-%d7/%a0-%a6 /* pop registers */
jmp (33*6-12+_VBR) /* jump exception 1 */
");
/* dispatch UART interrupt */
void xmit_interrupt(void);
void rcvr_interrupt(void);
void modem_status(void);
void _fake_trap_1(void);
void uart_interrupt(void) {
register char a;
a=*IIR & (NIP | IID_MASK); /* read interrupt id register */
switch (a) {
case 0x04: case 0x0c:
rcvr_interrupt();
break;
case 0x02:
xmit_interrupt();
break;
case 0x00:
modem_status();
break;
default:
break;
}
if (_debug_flag) {
_debug_flag = 0; /* reset the flag */
_fake_trap_1(); /* fake a trap #1 */
}
}
/* transfer received character to the buffer */
void rcvr_interrupt(void) {
register char *a, c;
register int length;
while ( (*LSR & DR) != 0) {
if ((c=*RBR) == 0x1a) /* use ctl-z to reboot */
reboot();
else if (c == 0x03) { /* use ctl-c to enter debugger */
_debug_flag = 1;
continue;
}
*(char *)((int)rcv.offset +(int)
(a=(char *)(((int)rcv.in+1) & ((int)BUFFER_LENGTH-1)))) = c;
if ((char *)(((int)rcv.in+2) & ((int)BUFFER_LENGTH-1)) != rcv.out)
rcv.in=a;
}
length = (BUFFER_LENGTH -1) & (
( ((int)rcv.out <= (int)rcv.in) ? 0 : BUFFER_LENGTH) - (int)rcv.out
+ (int)rcv.in + 1);
if (length >= RTS_STOP_SIZE)
*MCR &= (char) (~RTS);
}
/* tranfer buffered characters to the UART */
void xmit_interrupt(void) {
register short int i, oldsr;
_CPU_ISR_Disable( oldsr ); /* for when outbyte calls */
if ( (*LSR & THRE) != 0 && _tx_stop == 0 )
for (i=0;i<16;i++) {
if ((char *)(((int)xmt.in+1) & ((int)BUFFER_LENGTH-1))== xmt.out)
break;
*THR=*(char *)((int)xmt.offset+(int)xmt.out);
xmt.out= (char *)(((int)xmt.out+1) & ((int)BUFFER_LENGTH-1));
}
_CPU_ISR_Enable( oldsr );
}
void modem_status(void) {
register char a;
if ( ((a=*MDSR) & DCTS) != 0 )
if ( (a & CTS) == 0)
_tx_stop = 1;
else {
_tx_stop = 0;
xmit_interrupt();
}
}
/* transfer character from the buffer */
char inbyte(void) {
register char a;
register int length;
while ((char *)(((int)rcv.in+1) & ((int)BUFFER_LENGTH-1))== rcv.out);
a=*(char *)((int)rcv.offset+(int)rcv.out);
rcv.out= (char *)(((int)rcv.out+1) & ((int)BUFFER_LENGTH-1));
length = (BUFFER_LENGTH -1) & (
( ((int)rcv.out <= (int)rcv.in) ? 0 : BUFFER_LENGTH) - (int)rcv.out
+ (int)rcv.in + 1);
if (length < RTS_START_SIZE)
*MCR |= (char) RTS;
return (a);
}
/* once room is avaliable in the buffer, transfer
the character into the buffer and enable
the xmtr interrupt */
void outbyte(char c) {
register char *a;
while ((char *)(((int)xmt.in+2) & ((int)BUFFER_LENGTH-1)) == xmt.out);
*(char *)((int)xmt.offset+(int)
(a=(char *)(((int)xmt.in+1) & ((int)BUFFER_LENGTH-1))))=c;
xmt.in=a;
if ( (*LSR & THRE) != 0 ) /* if THRE, uart has already interrupted */
xmit_interrupt(); /* and was ignored. Need to restart. */
}
void _UART_flush(void) {
/* loop till xmt buffer empty. Works with interrupts disabled */
while ((char *)(((int)xmt.in+1) & ((int)BUFFER_LENGTH-1)) != xmt.out)
xmit_interrupt();
/* loop till UART buffer empty */
while ( (*LSR & TEMT) == 0 );
}
/* console_initialize
*
* This routine initializes the console IO driver.
*
* Input parameters: NONE
*
* Output parameters: NONE
*
* Return values:
*/
void console_init()
{
/* set clock divisor */
*LCR = (char)(DLAB);
*DLL = (char)((int)(CLK_FREQ/BAUD/16.0+0.5) & 0xFF);
*DLM = (char)(((int)(CLK_FREQ/BAUD/16.0+0.5) & 0xFF00) >> 8);
/* Line control setup */
*LCR = (char)(WL_8 | NSB);
/* Interrupt setup */
*IER = (char) 0x0b; /* enable transmit, receive, modem stat int */
/* FIFO setup */
*FCR = (char)(FIFO_E | 0xc0);
/* Modem control setup */
*MCR = (char) RTS;
/* init tx_stop with CTS */
_tx_stop = ( (*MDSR & CTS) ? 0 : 1);
set_vector(_catchUARTint, UART_ISR_LEVEL+24, 0);
}
rtems_device_driver console_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
rtems_status_code status;
status = rtems_io_register_name(
"/dev/console",
major,
(rtems_device_minor_number) 0
);
if (status != RTEMS_SUCCESSFUL)
rtems_fatal_error_occurred(status);
return RTEMS_SUCCESSFUL;
}
/* is_character_ready
*
* This routine returns TRUE if a character is available.
*
* Input parameters: NONE
*
* Output parameters: NONE
*
* Return values:
*/
rtems_boolean is_character_ready(
char *ch
)
{
if ((char *)(((int)rcv.in+1) & ((int)BUFFER_LENGTH-1))== rcv.out)
return(FALSE);
else
return(TRUE);
}
/*
* Open entry point
*/
rtems_device_driver console_open(
rtems_device_major_number major,
rtems_device_minor_number minor,
void * arg
)
{
return RTEMS_SUCCESSFUL;
}
/*
* Close entry point
*/
rtems_device_driver console_close(
rtems_device_major_number major,
rtems_device_minor_number minor,
void * arg
)
{
return RTEMS_SUCCESSFUL;
}
/*
* read bytes from the serial port. We only have stdin.
*/
rtems_device_driver console_read(
rtems_device_major_number major,
rtems_device_minor_number minor,
void * arg
)
{
rtems_libio_rw_args_t *rw_args;
char *buffer;
int maximum;
int count = 0;
rw_args = (rtems_libio_rw_args_t *) arg;
buffer = rw_args->buffer;
maximum = rw_args->count;
for (count = 0; count < maximum; count++) {
buffer[ count ] = inbyte();
if (buffer[ count ] == '\n' || buffer[ count ] == '\r') {
buffer[ count++ ] = '\n';
buffer[ count ] = 0;
break;
}
}
rw_args->bytes_moved = count;
return (count >= 0) ? RTEMS_SUCCESSFUL : RTEMS_UNSATISFIED;
}
/*
* write bytes to the serial port. Stdout and stderr are the same.
*/
rtems_device_driver console_write(
rtems_device_major_number major,
rtems_device_minor_number minor,
void * arg
)
{
int count;
int maximum;
rtems_libio_rw_args_t *rw_args;
char *buffer;
rw_args = (rtems_libio_rw_args_t *) arg;
buffer = rw_args->buffer;
maximum = rw_args->count;
for (count = 0; count < maximum; count++) {
if ( buffer[ count ] == '\n') {
outbyte('\r');
}
outbyte( buffer[ count ] );
}
rw_args->bytes_moved = maximum;
return 0;
}
/*
* IO Control entry point
*/
rtems_device_driver console_control(
rtems_device_major_number major,
rtems_device_minor_number minor,
void * arg
)
{
return RTEMS_SUCCESSFUL;
}
