source: rtems/c/src/lib/libbsp/hppa1.1/simhppa/tty/tty.c @ 556fb911

4.104.114.84.95
Last change on this file since 556fb911 was 556fb911, checked in by Joel Sherrill <joel.sherrill@…>, on 08/17/95 at 15:56:55

added tty driver to simhppa

  • Property mode set to 100644
File size: 6.1 KB
Line 
1/*
2 *  Tty IO Driver
3 *  This is a "libio" driver based on libc/support/generic/libio interface
4 *  which is on top of the RTEMS IO manager.
5 *
6 *  These provide UNIX-like read and write calls for the C library.
7 *
8 *  COPYRIGHT (c) 1994 by Division Incorporated
9 *
10 *  To anyone who acknowledges that this file is provided "AS IS"
11 *  without any express or implied warranty:
12 *      permission to use, copy, modify, and distribute this file
13 *      for any purpose is hereby granted without fee, provided that
14 *      the above copyright notice and this notice appears in all
15 *      copies, and that the name of Division Incorporated not be
16 *      used in advertising or publicity pertaining to distribution
17 *      of the software without specific, written prior permission.
18 *      Division Incorporated makes no representations about the
19 *      suitability of this software for any purpose.
20 *
21 *  tty.c,v 1.2 1995/05/09 20:17:14 joel Exp
22 */
23
24#include <bsp.h>
25#include <rtems/libio.h>
26
27#include <errno.h>
28
29#define PRINT_BUFFER_SIZE    (16 * 1024)
30
31/*
32 * NOTE: this structure is dumplicated in print_dump.c utility
33 */
34
35struct {
36    int  index;
37    int  size;
38    char buffer[PRINT_BUFFER_SIZE];
39} print_buffer;
40
41/* always use printf buffer if non-zero */
42int  use_print_buffer;
43
44static int host_read_syscall(int fd, char *buffer, int count);
45static int host_write_syscall(int fd, char *buffer, int count);
46
47rtems_device_driver
48tty_initialize(
49    rtems_device_major_number major,
50    rtems_device_minor_number minor,
51    void                    * arg
52  )
53{
54    rtems_status_code status;
55   
56    status = rtems_io_register_name("/dev/tty00",
57                                    major,
58                                    (rtems_device_minor_number) 0);
59    if (status != RTEMS_SUCCESSFUL)
60        rtems_fatal_error_occurred(status);
61
62    return RTEMS_SUCCESSFUL;
63}
64
65rtems_device_driver
66tty_open(
67    rtems_device_major_number major,
68    rtems_device_minor_number minor,
69    void                    * arg
70  )
71{
72    return RTEMS_SUCCESSFUL;
73}
74
75rtems_device_driver
76tty_close(
77    rtems_device_major_number major,
78    rtems_device_minor_number minor,
79    void                    * arg
80  )
81{
82    return RTEMS_SUCCESSFUL;
83}
84
85rtems_device_driver
86tty_control(
87    rtems_device_major_number major,
88    rtems_device_minor_number minor,
89    void                    * arg
90  )
91{
92    return RTEMS_SUCCESSFUL;
93}
94
95
96rtems_device_driver
97tty_read(
98    rtems_device_major_number major,
99    rtems_device_minor_number minor,
100    void                    * arg
101  )
102{
103    rtems_libio_rw_args_t *rw_args;
104    int count = 0;
105
106    rw_args = (rtems_libio_rw_args_t *) arg;
107
108    /*
109     * If we are printing to a buffer, then just return newline on all
110     * read's.  If we return 0 bytes read, then the pause() calls in
111     * the RTEMS tests get hosed (pause() does a gets())
112     */
113
114    if ( use_print_buffer )
115    {
116        *rw_args->buffer = '\n';
117        count = 1;
118    }
119    else
120    {
121        count = host_read_syscall(0, rw_args->buffer, rw_args->count);
122    }
123
124    if (count >= 0)
125    {
126        rw_args->bytes_moved = count;
127        return RTEMS_SUCCESSFUL;
128    }
129    return RTEMS_UNSATISFIED;
130}
131
132rtems_device_driver
133tty_write(
134    rtems_device_major_number major,
135    rtems_device_minor_number minor,
136    void                    * arg
137  )
138{
139    unsigned32 level;
140    rtems_libio_rw_args_t *rw_args;
141    int count = 0;
142    int fd = 1;                 /* XXX fixme; needs to be saved in iop */
143
144    rw_args = (rtems_libio_rw_args_t *) arg;
145
146    /*
147     * HACK alert
148     *
149     * Some of the simulators have real problems when multi cpu and
150     * using the system calls.  Until this is fixed, if we are multi
151     * cpu then we write to a printf buffer
152     */
153
154    if ( use_print_buffer )
155    {
156        /* save size in memory for dumper */
157        if (print_buffer.size == 0)
158            print_buffer.size = PRINT_BUFFER_SIZE;
159
160        while (rw_args->count-- > 0)
161        {
162            rtems_interrupt_disable(level);
163            print_buffer.buffer[print_buffer.index] = *rw_args->buffer++;
164            print_buffer.index++;
165            print_buffer.index &= (PRINT_BUFFER_SIZE - 1);
166            print_buffer.buffer[print_buffer.index] = 0;
167            rtems_interrupt_enable(level);
168            count++;
169        }
170    }
171    else
172    {
173#if 1
174        /*
175         * if on a multi cpu system and writing to stdout, redirect to stderr
176         * so we can keep them separate
177         */
178
179        if ((cpu_number == 1) && (fd == 1))
180            fd = 2;
181#endif
182        count = host_write_syscall(fd, rw_args->buffer, rw_args->count);
183    }
184
185    if (count >= 0)
186    {
187        rw_args->bytes_moved = count;
188        return RTEMS_SUCCESSFUL;
189    }
190    return RTEMS_UNSATISFIED;
191}
192
193
194/*
195 * Host system call hack.
196 * This little trick gets all the args in the right registers
197 * for the system call and permits simpler inline asm.
198 * Since this whole thing (syscalls under simulator) is a hack,
199 * this little bit more is not going to hurt anything.
200 */
201
202
203static int
204host_read_syscall(
205    int fd,
206    char *buffer,
207    int count
208  )
209{                   
210    unsigned32 level;
211    int rc;
212
213    rtems_interrupt_disable(level);
214
215    /* This is an HPUX system call, with return value copied out */
216    asm volatile (" stw     %%r19,-28(0,%%r30)\n\
217                    ldil    L%%0xc0000000,%%r1\n\
218                    ble     4(7,%%r1)\n\
219                    ldi     3,%%r22\n\
220                    ldw     -28(0,%%r30),%%r19\n\
221                    copy    %%r28, %0"
222                  : "=r" (rc)
223                  : );
224
225    rtems_interrupt_enable(level);
226    return rc;
227}
228
229static int
230host_write_syscall(
231    int fd,
232    char *buffer,
233    int count
234  )
235{                   
236    unsigned32 level;
237    int rc;
238
239    rtems_interrupt_disable(level);
240
241    /* This is an HPUX system call, with return value copied out */
242    asm volatile (" stw     %%r19,-28(0,%%r30)\n\
243                    ldil    L%%0xc0000000,%%r1\n\
244                    ble     4(7,%%r1)\n\
245                    ldi     4,%%r22\n\
246                    ldw     -28(0,%%r30),%%r19\n\
247                    copy    %%r28, %0"
248                  : "=r" (rc)
249                  : );
250
251    rtems_interrupt_enable(level);
252    return rc;
253}
254
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