ixgbe: Set Priority Flow Control low water threshhold for DCB
[linux-2.6] / drivers / char / vme_scc.c
1 /*
2  * drivers/char/vme_scc.c: MVME147, MVME162, BVME6000 SCC serial ports
3  * implementation.
4  * Copyright 1999 Richard Hirst <richard@sleepie.demon.co.uk>
5  *
6  * Based on atari_SCC.c which was
7  *   Copyright 1994-95 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
8  *   Partially based on PC-Linux serial.c by Linus Torvalds and Theodore Ts'o
9  *
10  * This file is subject to the terms and conditions of the GNU General Public
11  * License.  See the file COPYING in the main directory of this archive
12  * for more details.
13  *
14  */
15
16 #include <linux/module.h>
17 #include <linux/kdev_t.h>
18 #include <asm/io.h>
19 #include <linux/kernel.h>
20 #include <linux/ioport.h>
21 #include <linux/interrupt.h>
22 #include <linux/errno.h>
23 #include <linux/tty.h>
24 #include <linux/tty_flip.h>
25 #include <linux/mm.h>
26 #include <linux/serial.h>
27 #include <linux/fcntl.h>
28 #include <linux/major.h>
29 #include <linux/delay.h>
30 #include <linux/slab.h>
31 #include <linux/miscdevice.h>
32 #include <linux/console.h>
33 #include <linux/init.h>
34 #include <asm/setup.h>
35 #include <asm/bootinfo.h>
36
37 #ifdef CONFIG_MVME147_SCC
38 #include <asm/mvme147hw.h>
39 #endif
40 #ifdef CONFIG_MVME162_SCC
41 #include <asm/mvme16xhw.h>
42 #endif
43 #ifdef CONFIG_BVME6000_SCC
44 #include <asm/bvme6000hw.h>
45 #endif
46
47 #include <linux/generic_serial.h>
48 #include "scc.h"
49
50
51 #define CHANNEL_A       0
52 #define CHANNEL_B       1
53
54 #define SCC_MINOR_BASE  64
55
56 /* Shadows for all SCC write registers */
57 static unsigned char scc_shadow[2][16];
58
59 /* Location to access for SCC register access delay */
60 static volatile unsigned char *scc_del = NULL;
61
62 /* To keep track of STATUS_REG state for detection of Ext/Status int source */
63 static unsigned char scc_last_status_reg[2];
64
65 /***************************** Prototypes *****************************/
66
67 /* Function prototypes */
68 static void scc_disable_tx_interrupts(void * ptr);
69 static void scc_enable_tx_interrupts(void * ptr);
70 static void scc_disable_rx_interrupts(void * ptr);
71 static void scc_enable_rx_interrupts(void * ptr);
72 static int  scc_carrier_raised(struct tty_port *port);
73 static void scc_shutdown_port(void * ptr);
74 static int scc_set_real_termios(void  *ptr);
75 static void scc_hungup(void  *ptr);
76 static void scc_close(void  *ptr);
77 static int scc_chars_in_buffer(void * ptr);
78 static int scc_open(struct tty_struct * tty, struct file * filp);
79 static int scc_ioctl(struct tty_struct * tty, struct file * filp,
80                      unsigned int cmd, unsigned long arg);
81 static void scc_throttle(struct tty_struct *tty);
82 static void scc_unthrottle(struct tty_struct *tty);
83 static irqreturn_t scc_tx_int(int irq, void *data);
84 static irqreturn_t scc_rx_int(int irq, void *data);
85 static irqreturn_t scc_stat_int(int irq, void *data);
86 static irqreturn_t scc_spcond_int(int irq, void *data);
87 static void scc_setsignals(struct scc_port *port, int dtr, int rts);
88 static int scc_break_ctl(struct tty_struct *tty, int break_state);
89
90 static struct tty_driver *scc_driver;
91
92 static struct scc_port scc_ports[2];
93
94 /*---------------------------------------------------------------------------
95  * Interface from generic_serial.c back here
96  *--------------------------------------------------------------------------*/
97
98 static struct real_driver scc_real_driver = {
99         scc_disable_tx_interrupts,
100         scc_enable_tx_interrupts,
101         scc_disable_rx_interrupts,
102         scc_enable_rx_interrupts,
103         scc_shutdown_port,
104         scc_set_real_termios,
105         scc_chars_in_buffer,
106         scc_close,
107         scc_hungup,
108         NULL
109 };
110
111
112 static const struct tty_operations scc_ops = {
113         .open   = scc_open,
114         .close = gs_close,
115         .write = gs_write,
116         .put_char = gs_put_char,
117         .flush_chars = gs_flush_chars,
118         .write_room = gs_write_room,
119         .chars_in_buffer = gs_chars_in_buffer,
120         .flush_buffer = gs_flush_buffer,
121         .ioctl = scc_ioctl,
122         .throttle = scc_throttle,
123         .unthrottle = scc_unthrottle,
124         .set_termios = gs_set_termios,
125         .stop = gs_stop,
126         .start = gs_start,
127         .hangup = gs_hangup,
128         .break_ctl = scc_break_ctl,
129 };
130
131 static const struct tty_port_operations scc_port_ops = {
132         .carrier_raised = scc_carrier_raised,
133 };
134
135 /*----------------------------------------------------------------------------
136  * vme_scc_init() and support functions
137  *---------------------------------------------------------------------------*/
138
139 static int scc_init_drivers(void)
140 {
141         int error;
142
143         scc_driver = alloc_tty_driver(2);
144         if (!scc_driver)
145                 return -ENOMEM;
146         scc_driver->owner = THIS_MODULE;
147         scc_driver->driver_name = "scc";
148         scc_driver->name = "ttyS";
149         scc_driver->major = TTY_MAJOR;
150         scc_driver->minor_start = SCC_MINOR_BASE;
151         scc_driver->type = TTY_DRIVER_TYPE_SERIAL;
152         scc_driver->subtype = SERIAL_TYPE_NORMAL;
153         scc_driver->init_termios = tty_std_termios;
154         scc_driver->init_termios.c_cflag =
155           B9600 | CS8 | CREAD | HUPCL | CLOCAL;
156         scc_driver->init_termios.c_ispeed = 9600;
157         scc_driver->init_termios.c_ospeed = 9600;
158         scc_driver->flags = TTY_DRIVER_REAL_RAW;
159         tty_set_operations(scc_driver, &scc_ops);
160
161         if ((error = tty_register_driver(scc_driver))) {
162                 printk(KERN_ERR "scc: Couldn't register scc driver, error = %d\n",
163                        error);
164                 put_tty_driver(scc_driver);
165                 return 1;
166         }
167
168         return 0;
169 }
170
171
172 /* ports[] array is indexed by line no (i.e. [0] for ttyS0, [1] for ttyS1).
173  */
174
175 static void scc_init_portstructs(void)
176 {
177         struct scc_port *port;
178         int i;
179
180         for (i = 0; i < 2; i++) {
181                 port = scc_ports + i;
182                 tty_port_init(&port->gs.port);
183                 port->gs.port.ops = &scc_port_ops;
184                 port->gs.magic = SCC_MAGIC;
185                 port->gs.close_delay = HZ/2;
186                 port->gs.closing_wait = 30 * HZ;
187                 port->gs.rd = &scc_real_driver;
188 #ifdef NEW_WRITE_LOCKING
189                 port->gs.port_write_mutex = MUTEX;
190 #endif
191                 init_waitqueue_head(&port->gs.port.open_wait);
192                 init_waitqueue_head(&port->gs.port.close_wait);
193         }
194 }
195
196
197 #ifdef CONFIG_MVME147_SCC
198 static int mvme147_scc_init(void)
199 {
200         struct scc_port *port;
201         int error;
202
203         printk(KERN_INFO "SCC: MVME147 Serial Driver\n");
204         /* Init channel A */
205         port = &scc_ports[0];
206         port->channel = CHANNEL_A;
207         port->ctrlp = (volatile unsigned char *)M147_SCC_A_ADDR;
208         port->datap = port->ctrlp + 1;
209         port->port_a = &scc_ports[0];
210         port->port_b = &scc_ports[1];
211         error = request_irq(MVME147_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
212                             "SCC-A TX", port);
213         if (error)
214                 goto fail;
215         error = request_irq(MVME147_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
216                             "SCC-A status", port);
217         if (error)
218                 goto fail_free_a_tx;
219         error = request_irq(MVME147_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
220                             "SCC-A RX", port);
221         if (error)
222                 goto fail_free_a_stat;
223         error = request_irq(MVME147_IRQ_SCCA_SPCOND, scc_spcond_int,
224                             IRQF_DISABLED, "SCC-A special cond", port);
225         if (error)
226                 goto fail_free_a_rx;
227
228         {
229                 SCC_ACCESS_INIT(port);
230
231                 /* disable interrupts for this channel */
232                 SCCwrite(INT_AND_DMA_REG, 0);
233                 /* Set the interrupt vector */
234                 SCCwrite(INT_VECTOR_REG, MVME147_IRQ_SCC_BASE);
235                 /* Interrupt parameters: vector includes status, status low */
236                 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
237                 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
238         }
239
240         /* Init channel B */
241         port = &scc_ports[1];
242         port->channel = CHANNEL_B;
243         port->ctrlp = (volatile unsigned char *)M147_SCC_B_ADDR;
244         port->datap = port->ctrlp + 1;
245         port->port_a = &scc_ports[0];
246         port->port_b = &scc_ports[1];
247         error = request_irq(MVME147_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
248                             "SCC-B TX", port);
249         if (error)
250                 goto fail_free_a_spcond;
251         error = request_irq(MVME147_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
252                             "SCC-B status", port);
253         if (error)
254                 goto fail_free_b_tx;
255         error = request_irq(MVME147_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
256                             "SCC-B RX", port);
257         if (error)
258                 goto fail_free_b_stat;
259         error = request_irq(MVME147_IRQ_SCCB_SPCOND, scc_spcond_int,
260                             IRQF_DISABLED, "SCC-B special cond", port);
261         if (error)
262                 goto fail_free_b_rx;
263
264         {
265                 SCC_ACCESS_INIT(port);
266
267                 /* disable interrupts for this channel */
268                 SCCwrite(INT_AND_DMA_REG, 0);
269         }
270
271         /* Ensure interrupts are enabled in the PCC chip */
272         m147_pcc->serial_cntrl=PCC_LEVEL_SERIAL|PCC_INT_ENAB;
273
274         /* Initialise the tty driver structures and register */
275         scc_init_portstructs();
276         scc_init_drivers();
277
278         return 0;
279
280 fail_free_b_rx:
281         free_irq(MVME147_IRQ_SCCB_RX, port);
282 fail_free_b_stat:
283         free_irq(MVME147_IRQ_SCCB_STAT, port);
284 fail_free_b_tx:
285         free_irq(MVME147_IRQ_SCCB_TX, port);
286 fail_free_a_spcond:
287         free_irq(MVME147_IRQ_SCCA_SPCOND, port);
288 fail_free_a_rx:
289         free_irq(MVME147_IRQ_SCCA_RX, port);
290 fail_free_a_stat:
291         free_irq(MVME147_IRQ_SCCA_STAT, port);
292 fail_free_a_tx:
293         free_irq(MVME147_IRQ_SCCA_TX, port);
294 fail:
295         return error;
296 }
297 #endif
298
299
300 #ifdef CONFIG_MVME162_SCC
301 static int mvme162_scc_init(void)
302 {
303         struct scc_port *port;
304         int error;
305
306         if (!(mvme16x_config & MVME16x_CONFIG_GOT_SCCA))
307                 return (-ENODEV);
308
309         printk(KERN_INFO "SCC: MVME162 Serial Driver\n");
310         /* Init channel A */
311         port = &scc_ports[0];
312         port->channel = CHANNEL_A;
313         port->ctrlp = (volatile unsigned char *)MVME_SCC_A_ADDR;
314         port->datap = port->ctrlp + 2;
315         port->port_a = &scc_ports[0];
316         port->port_b = &scc_ports[1];
317         error = request_irq(MVME162_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
318                             "SCC-A TX", port);
319         if (error)
320                 goto fail;
321         error = request_irq(MVME162_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
322                             "SCC-A status", port);
323         if (error)
324                 goto fail_free_a_tx;
325         error = request_irq(MVME162_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
326                             "SCC-A RX", port);
327         if (error)
328                 goto fail_free_a_stat;
329         error = request_irq(MVME162_IRQ_SCCA_SPCOND, scc_spcond_int,
330                             IRQF_DISABLED, "SCC-A special cond", port);
331         if (error)
332                 goto fail_free_a_rx;
333
334         {
335                 SCC_ACCESS_INIT(port);
336
337                 /* disable interrupts for this channel */
338                 SCCwrite(INT_AND_DMA_REG, 0);
339                 /* Set the interrupt vector */
340                 SCCwrite(INT_VECTOR_REG, MVME162_IRQ_SCC_BASE);
341                 /* Interrupt parameters: vector includes status, status low */
342                 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
343                 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
344         }
345
346         /* Init channel B */
347         port = &scc_ports[1];
348         port->channel = CHANNEL_B;
349         port->ctrlp = (volatile unsigned char *)MVME_SCC_B_ADDR;
350         port->datap = port->ctrlp + 2;
351         port->port_a = &scc_ports[0];
352         port->port_b = &scc_ports[1];
353         error = request_irq(MVME162_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
354                             "SCC-B TX", port);
355         if (error)
356                 goto fail_free_a_spcond;
357         error = request_irq(MVME162_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
358                             "SCC-B status", port);
359         if (error)
360                 goto fail_free_b_tx;
361         error = request_irq(MVME162_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
362                             "SCC-B RX", port);
363         if (error)
364                 goto fail_free_b_stat;
365         error = request_irq(MVME162_IRQ_SCCB_SPCOND, scc_spcond_int,
366                             IRQF_DISABLED, "SCC-B special cond", port);
367         if (error)
368                 goto fail_free_b_rx;
369
370         {
371                 SCC_ACCESS_INIT(port);  /* Either channel will do */
372
373                 /* disable interrupts for this channel */
374                 SCCwrite(INT_AND_DMA_REG, 0);
375         }
376
377         /* Ensure interrupts are enabled in the MC2 chip */
378         *(volatile char *)0xfff4201d = 0x14;
379
380         /* Initialise the tty driver structures and register */
381         scc_init_portstructs();
382         scc_init_drivers();
383
384         return 0;
385
386 fail_free_b_rx:
387         free_irq(MVME162_IRQ_SCCB_RX, port);
388 fail_free_b_stat:
389         free_irq(MVME162_IRQ_SCCB_STAT, port);
390 fail_free_b_tx:
391         free_irq(MVME162_IRQ_SCCB_TX, port);
392 fail_free_a_spcond:
393         free_irq(MVME162_IRQ_SCCA_SPCOND, port);
394 fail_free_a_rx:
395         free_irq(MVME162_IRQ_SCCA_RX, port);
396 fail_free_a_stat:
397         free_irq(MVME162_IRQ_SCCA_STAT, port);
398 fail_free_a_tx:
399         free_irq(MVME162_IRQ_SCCA_TX, port);
400 fail:
401         return error;
402 }
403 #endif
404
405
406 #ifdef CONFIG_BVME6000_SCC
407 static int bvme6000_scc_init(void)
408 {
409         struct scc_port *port;
410         int error;
411
412         printk(KERN_INFO "SCC: BVME6000 Serial Driver\n");
413         /* Init channel A */
414         port = &scc_ports[0];
415         port->channel = CHANNEL_A;
416         port->ctrlp = (volatile unsigned char *)BVME_SCC_A_ADDR;
417         port->datap = port->ctrlp + 4;
418         port->port_a = &scc_ports[0];
419         port->port_b = &scc_ports[1];
420         error = request_irq(BVME_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
421                             "SCC-A TX", port);
422         if (error)
423                 goto fail;
424         error = request_irq(BVME_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
425                             "SCC-A status", port);
426         if (error)
427                 goto fail_free_a_tx;
428         error = request_irq(BVME_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
429                             "SCC-A RX", port);
430         if (error)
431                 goto fail_free_a_stat;
432         error = request_irq(BVME_IRQ_SCCA_SPCOND, scc_spcond_int,
433                             IRQF_DISABLED, "SCC-A special cond", port);
434         if (error)
435                 goto fail_free_a_rx;
436
437         {
438                 SCC_ACCESS_INIT(port);
439
440                 /* disable interrupts for this channel */
441                 SCCwrite(INT_AND_DMA_REG, 0);
442                 /* Set the interrupt vector */
443                 SCCwrite(INT_VECTOR_REG, BVME_IRQ_SCC_BASE);
444                 /* Interrupt parameters: vector includes status, status low */
445                 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
446                 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
447         }
448
449         /* Init channel B */
450         port = &scc_ports[1];
451         port->channel = CHANNEL_B;
452         port->ctrlp = (volatile unsigned char *)BVME_SCC_B_ADDR;
453         port->datap = port->ctrlp + 4;
454         port->port_a = &scc_ports[0];
455         port->port_b = &scc_ports[1];
456         error = request_irq(BVME_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
457                             "SCC-B TX", port);
458         if (error)
459                 goto fail_free_a_spcond;
460         error = request_irq(BVME_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
461                             "SCC-B status", port);
462         if (error)
463                 goto fail_free_b_tx;
464         error = request_irq(BVME_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
465                             "SCC-B RX", port);
466         if (error)
467                 goto fail_free_b_stat;
468         error = request_irq(BVME_IRQ_SCCB_SPCOND, scc_spcond_int,
469                             IRQF_DISABLED, "SCC-B special cond", port);
470         if (error)
471                 goto fail_free_b_rx;
472
473         {
474                 SCC_ACCESS_INIT(port);  /* Either channel will do */
475
476                 /* disable interrupts for this channel */
477                 SCCwrite(INT_AND_DMA_REG, 0);
478         }
479
480         /* Initialise the tty driver structures and register */
481         scc_init_portstructs();
482         scc_init_drivers();
483
484         return 0;
485
486 fail:
487         free_irq(BVME_IRQ_SCCA_STAT, port);
488 fail_free_a_tx:
489         free_irq(BVME_IRQ_SCCA_RX, port);
490 fail_free_a_stat:
491         free_irq(BVME_IRQ_SCCA_SPCOND, port);
492 fail_free_a_rx:
493         free_irq(BVME_IRQ_SCCB_TX, port);
494 fail_free_a_spcond:
495         free_irq(BVME_IRQ_SCCB_STAT, port);
496 fail_free_b_tx:
497         free_irq(BVME_IRQ_SCCB_RX, port);
498 fail_free_b_stat:
499         free_irq(BVME_IRQ_SCCB_SPCOND, port);
500 fail_free_b_rx:
501         return error;
502 }
503 #endif
504
505
506 static int vme_scc_init(void)
507 {
508         int res = -ENODEV;
509
510 #ifdef CONFIG_MVME147_SCC
511         if (MACH_IS_MVME147)
512                 res = mvme147_scc_init();
513 #endif
514 #ifdef CONFIG_MVME162_SCC
515         if (MACH_IS_MVME16x)
516                 res = mvme162_scc_init();
517 #endif
518 #ifdef CONFIG_BVME6000_SCC
519         if (MACH_IS_BVME6000)
520                 res = bvme6000_scc_init();
521 #endif
522         return res;
523 }
524
525 module_init(vme_scc_init);
526
527
528 /*---------------------------------------------------------------------------
529  * Interrupt handlers
530  *--------------------------------------------------------------------------*/
531
532 static irqreturn_t scc_rx_int(int irq, void *data)
533 {
534         unsigned char   ch;
535         struct scc_port *port = data;
536         struct tty_struct *tty = port->gs.port.tty;
537         SCC_ACCESS_INIT(port);
538
539         ch = SCCread_NB(RX_DATA_REG);
540         if (!tty) {
541                 printk(KERN_WARNING "scc_rx_int with NULL tty!\n");
542                 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
543                 return IRQ_HANDLED;
544         }
545         tty_insert_flip_char(tty, ch, 0);
546
547         /* Check if another character is already ready; in that case, the
548          * spcond_int() function must be used, because this character may have an
549          * error condition that isn't signalled by the interrupt vector used!
550          */
551         if (SCCread(INT_PENDING_REG) &
552             (port->channel == CHANNEL_A ? IPR_A_RX : IPR_B_RX)) {
553                 scc_spcond_int (irq, data);
554                 return IRQ_HANDLED;
555         }
556
557         SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
558
559         tty_flip_buffer_push(tty);
560         return IRQ_HANDLED;
561 }
562
563
564 static irqreturn_t scc_spcond_int(int irq, void *data)
565 {
566         struct scc_port *port = data;
567         struct tty_struct *tty = port->gs.port.tty;
568         unsigned char   stat, ch, err;
569         int             int_pending_mask = port->channel == CHANNEL_A ?
570                                            IPR_A_RX : IPR_B_RX;
571         SCC_ACCESS_INIT(port);
572         
573         if (!tty) {
574                 printk(KERN_WARNING "scc_spcond_int with NULL tty!\n");
575                 SCCwrite(COMMAND_REG, CR_ERROR_RESET);
576                 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
577                 return IRQ_HANDLED;
578         }
579         do {
580                 stat = SCCread(SPCOND_STATUS_REG);
581                 ch = SCCread_NB(RX_DATA_REG);
582
583                 if (stat & SCSR_RX_OVERRUN)
584                         err = TTY_OVERRUN;
585                 else if (stat & SCSR_PARITY_ERR)
586                         err = TTY_PARITY;
587                 else if (stat & SCSR_CRC_FRAME_ERR)
588                         err = TTY_FRAME;
589                 else
590                         err = 0;
591
592                 tty_insert_flip_char(tty, ch, err);
593
594                 /* ++TeSche: *All* errors have to be cleared manually,
595                  * else the condition persists for the next chars
596                  */
597                 if (err)
598                   SCCwrite(COMMAND_REG, CR_ERROR_RESET);
599
600         } while(SCCread(INT_PENDING_REG) & int_pending_mask);
601
602         SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
603
604         tty_flip_buffer_push(tty);
605         return IRQ_HANDLED;
606 }
607
608
609 static irqreturn_t scc_tx_int(int irq, void *data)
610 {
611         struct scc_port *port = data;
612         SCC_ACCESS_INIT(port);
613
614         if (!port->gs.port.tty) {
615                 printk(KERN_WARNING "scc_tx_int with NULL tty!\n");
616                 SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
617                 SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET);
618                 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
619                 return IRQ_HANDLED;
620         }
621         while ((SCCread_NB(STATUS_REG) & SR_TX_BUF_EMPTY)) {
622                 if (port->x_char) {
623                         SCCwrite(TX_DATA_REG, port->x_char);
624                         port->x_char = 0;
625                 }
626                 else if ((port->gs.xmit_cnt <= 0) ||
627                          port->gs.port.tty->stopped ||
628                          port->gs.port.tty->hw_stopped)
629                         break;
630                 else {
631                         SCCwrite(TX_DATA_REG, port->gs.xmit_buf[port->gs.xmit_tail++]);
632                         port->gs.xmit_tail = port->gs.xmit_tail & (SERIAL_XMIT_SIZE-1);
633                         if (--port->gs.xmit_cnt <= 0)
634                                 break;
635                 }
636         }
637         if ((port->gs.xmit_cnt <= 0) || port->gs.port.tty->stopped ||
638             port->gs.port.tty->hw_stopped) {
639                 /* disable tx interrupts */
640                 SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
641                 SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET);   /* disable tx_int on next tx underrun? */
642                 port->gs.port.flags &= ~GS_TX_INTEN;
643         }
644         if (port->gs.port.tty && port->gs.xmit_cnt <= port->gs.wakeup_chars)
645                 tty_wakeup(port->gs.port.tty);
646
647         SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
648         return IRQ_HANDLED;
649 }
650
651
652 static irqreturn_t scc_stat_int(int irq, void *data)
653 {
654         struct scc_port *port = data;
655         unsigned channel = port->channel;
656         unsigned char   last_sr, sr, changed;
657         SCC_ACCESS_INIT(port);
658
659         last_sr = scc_last_status_reg[channel];
660         sr = scc_last_status_reg[channel] = SCCread_NB(STATUS_REG);
661         changed = last_sr ^ sr;
662
663         if (changed & SR_DCD) {
664                 port->c_dcd = !!(sr & SR_DCD);
665                 if (!(port->gs.port.flags & ASYNC_CHECK_CD))
666                         ;       /* Don't report DCD changes */
667                 else if (port->c_dcd) {
668                         wake_up_interruptible(&port->gs.port.open_wait);
669                 }
670                 else {
671                         if (port->gs.port.tty)
672                                 tty_hangup (port->gs.port.tty);
673                 }
674         }
675         SCCwrite(COMMAND_REG, CR_EXTSTAT_RESET);
676         SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
677         return IRQ_HANDLED;
678 }
679
680
681 /*---------------------------------------------------------------------------
682  * generic_serial.c callback funtions
683  *--------------------------------------------------------------------------*/
684
685 static void scc_disable_tx_interrupts(void *ptr)
686 {
687         struct scc_port *port = ptr;
688         unsigned long   flags;
689         SCC_ACCESS_INIT(port);
690
691         local_irq_save(flags);
692         SCCmod(INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
693         port->gs.port.flags &= ~GS_TX_INTEN;
694         local_irq_restore(flags);
695 }
696
697
698 static void scc_enable_tx_interrupts(void *ptr)
699 {
700         struct scc_port *port = ptr;
701         unsigned long   flags;
702         SCC_ACCESS_INIT(port);
703
704         local_irq_save(flags);
705         SCCmod(INT_AND_DMA_REG, 0xff, IDR_TX_INT_ENAB);
706         /* restart the transmitter */
707         scc_tx_int (0, port);
708         local_irq_restore(flags);
709 }
710
711
712 static void scc_disable_rx_interrupts(void *ptr)
713 {
714         struct scc_port *port = ptr;
715         unsigned long   flags;
716         SCC_ACCESS_INIT(port);
717
718         local_irq_save(flags);
719         SCCmod(INT_AND_DMA_REG,
720             ~(IDR_RX_INT_MASK|IDR_PARERR_AS_SPCOND|IDR_EXTSTAT_INT_ENAB), 0);
721         local_irq_restore(flags);
722 }
723
724
725 static void scc_enable_rx_interrupts(void *ptr)
726 {
727         struct scc_port *port = ptr;
728         unsigned long   flags;
729         SCC_ACCESS_INIT(port);
730
731         local_irq_save(flags);
732         SCCmod(INT_AND_DMA_REG, 0xff,
733                 IDR_EXTSTAT_INT_ENAB|IDR_PARERR_AS_SPCOND|IDR_RX_INT_ALL);
734         local_irq_restore(flags);
735 }
736
737
738 static int scc_carrier_raised(struct tty_port *port)
739 {
740         struct scc_port *sc = container_of(port, struct scc_port, gs.port);
741         unsigned channel = sc->channel;
742
743         return !!(scc_last_status_reg[channel] & SR_DCD);
744 }
745
746
747 static void scc_shutdown_port(void *ptr)
748 {
749         struct scc_port *port = ptr;
750
751         port->gs.port.flags &= ~ GS_ACTIVE;
752         if (port->gs.port.tty && (port->gs.port.tty->termios->c_cflag & HUPCL)) {
753                 scc_setsignals (port, 0, 0);
754         }
755 }
756
757
758 static int scc_set_real_termios (void *ptr)
759 {
760         /* the SCC has char sizes 5,7,6,8 in that order! */
761         static int chsize_map[4] = { 0, 2, 1, 3 };
762         unsigned cflag, baud, chsize, channel, brgval = 0;
763         unsigned long flags;
764         struct scc_port *port = ptr;
765         SCC_ACCESS_INIT(port);
766
767         if (!port->gs.port.tty || !port->gs.port.tty->termios) return 0;
768
769         channel = port->channel;
770
771         if (channel == CHANNEL_A)
772                 return 0;               /* Settings controlled by boot PROM */
773
774         cflag  = port->gs.port.tty->termios->c_cflag;
775         baud = port->gs.baud;
776         chsize = (cflag & CSIZE) >> 4;
777
778         if (baud == 0) {
779                 /* speed == 0 -> drop DTR */
780                 local_irq_save(flags);
781                 SCCmod(TX_CTRL_REG, ~TCR_DTR, 0);
782                 local_irq_restore(flags);
783                 return 0;
784         }
785         else if ((MACH_IS_MVME16x && (baud < 50 || baud > 38400)) ||
786                  (MACH_IS_MVME147 && (baud < 50 || baud > 19200)) ||
787                  (MACH_IS_BVME6000 &&(baud < 50 || baud > 76800))) {
788                 printk(KERN_NOTICE "SCC: Bad speed requested, %d\n", baud);
789                 return 0;
790         }
791
792         if (cflag & CLOCAL)
793                 port->gs.port.flags &= ~ASYNC_CHECK_CD;
794         else
795                 port->gs.port.flags |= ASYNC_CHECK_CD;
796
797 #ifdef CONFIG_MVME147_SCC
798         if (MACH_IS_MVME147)
799                 brgval = (M147_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
800 #endif
801 #ifdef CONFIG_MVME162_SCC
802         if (MACH_IS_MVME16x)
803                 brgval = (MVME_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
804 #endif
805 #ifdef CONFIG_BVME6000_SCC
806         if (MACH_IS_BVME6000)
807                 brgval = (BVME_SCC_RTxC + baud/2) / (16 * 2 * baud) - 2;
808 #endif
809         /* Now we have all parameters and can go to set them: */
810         local_irq_save(flags);
811
812         /* receiver's character size and auto-enables */
813         SCCmod(RX_CTRL_REG, ~(RCR_CHSIZE_MASK|RCR_AUTO_ENAB_MODE),
814                         (chsize_map[chsize] << 6) |
815                         ((cflag & CRTSCTS) ? RCR_AUTO_ENAB_MODE : 0));
816         /* parity and stop bits (both, Tx and Rx), clock mode never changes */
817         SCCmod (AUX1_CTRL_REG,
818                 ~(A1CR_PARITY_MASK | A1CR_MODE_MASK),
819                 ((cflag & PARENB
820                   ? (cflag & PARODD ? A1CR_PARITY_ODD : A1CR_PARITY_EVEN)
821                   : A1CR_PARITY_NONE)
822                  | (cflag & CSTOPB ? A1CR_MODE_ASYNC_2 : A1CR_MODE_ASYNC_1)));
823         /* sender's character size, set DTR for valid baud rate */
824         SCCmod(TX_CTRL_REG, ~TCR_CHSIZE_MASK, chsize_map[chsize] << 5 | TCR_DTR);
825         /* clock sources never change */
826         /* disable BRG before changing the value */
827         SCCmod(DPLL_CTRL_REG, ~DCR_BRG_ENAB, 0);
828         /* BRG value */
829         SCCwrite(TIMER_LOW_REG, brgval & 0xff);
830         SCCwrite(TIMER_HIGH_REG, (brgval >> 8) & 0xff);
831         /* BRG enable, and clock source never changes */
832         SCCmod(DPLL_CTRL_REG, 0xff, DCR_BRG_ENAB);
833
834         local_irq_restore(flags);
835
836         return 0;
837 }
838
839
840 static int scc_chars_in_buffer (void *ptr)
841 {
842         struct scc_port *port = ptr;
843         SCC_ACCESS_INIT(port);
844
845         return (SCCread (SPCOND_STATUS_REG) & SCSR_ALL_SENT) ? 0  : 1;
846 }
847
848
849 /* Comment taken from sx.c (2.4.0):
850    I haven't the foggiest why the decrement use count has to happen
851    here. The whole linux serial drivers stuff needs to be redesigned.
852    My guess is that this is a hack to minimize the impact of a bug
853    elsewhere. Thinking about it some more. (try it sometime) Try
854    running minicom on a serial port that is driven by a modularized
855    driver. Have the modem hangup. Then remove the driver module. Then
856    exit minicom.  I expect an "oops".  -- REW */
857
858 static void scc_hungup(void *ptr)
859 {
860         scc_disable_tx_interrupts(ptr);
861         scc_disable_rx_interrupts(ptr);
862 }
863
864
865 static void scc_close(void *ptr)
866 {
867         scc_disable_tx_interrupts(ptr);
868         scc_disable_rx_interrupts(ptr);
869 }
870
871
872 /*---------------------------------------------------------------------------
873  * Internal support functions
874  *--------------------------------------------------------------------------*/
875
876 static void scc_setsignals(struct scc_port *port, int dtr, int rts)
877 {
878         unsigned long flags;
879         unsigned char t;
880         SCC_ACCESS_INIT(port);
881
882         local_irq_save(flags);
883         t = SCCread(TX_CTRL_REG);
884         if (dtr >= 0) t = dtr? (t | TCR_DTR): (t & ~TCR_DTR);
885         if (rts >= 0) t = rts? (t | TCR_RTS): (t & ~TCR_RTS);
886         SCCwrite(TX_CTRL_REG, t);
887         local_irq_restore(flags);
888 }
889
890
891 static void scc_send_xchar(struct tty_struct *tty, char ch)
892 {
893         struct scc_port *port = tty->driver_data;
894
895         port->x_char = ch;
896         if (ch)
897                 scc_enable_tx_interrupts(port);
898 }
899
900
901 /*---------------------------------------------------------------------------
902  * Driver entrypoints referenced from above
903  *--------------------------------------------------------------------------*/
904
905 static int scc_open (struct tty_struct * tty, struct file * filp)
906 {
907         int line = tty->index;
908         int retval;
909         struct scc_port *port = &scc_ports[line];
910         int i, channel = port->channel;
911         unsigned long   flags;
912         SCC_ACCESS_INIT(port);
913 #if defined(CONFIG_MVME162_SCC) || defined(CONFIG_MVME147_SCC)
914         static const struct {
915                 unsigned reg, val;
916         } mvme_init_tab[] = {
917                 /* Values for MVME162 and MVME147 */
918                 /* no parity, 1 stop bit, async, 1:16 */
919                 { AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
920                 /* parity error is special cond, ints disabled, no DMA */
921                 { INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
922                 /* Rx 8 bits/char, no auto enable, Rx off */
923                 { RX_CTRL_REG, RCR_CHSIZE_8 },
924                 /* DTR off, Tx 8 bits/char, RTS off, Tx off */
925                 { TX_CTRL_REG, TCR_CHSIZE_8 },
926                 /* special features off */
927                 { AUX2_CTRL_REG, 0 },
928                 { CLK_CTRL_REG, CCR_RXCLK_BRG | CCR_TXCLK_BRG },
929                 { DPLL_CTRL_REG, DCR_BRG_ENAB | DCR_BRG_USE_PCLK },
930                 /* Start Rx */
931                 { RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
932                 /* Start Tx */
933                 { TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
934                 /* Ext/Stat ints: DCD only */
935                 { INT_CTRL_REG, ICR_ENAB_DCD_INT },
936                 /* Reset Ext/Stat ints */
937                 { COMMAND_REG, CR_EXTSTAT_RESET },
938                 /* ...again */
939                 { COMMAND_REG, CR_EXTSTAT_RESET },
940         };
941 #endif
942 #if defined(CONFIG_BVME6000_SCC)
943         static const struct {
944                 unsigned reg, val;
945         } bvme_init_tab[] = {
946                 /* Values for BVME6000 */
947                 /* no parity, 1 stop bit, async, 1:16 */
948                 { AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
949                 /* parity error is special cond, ints disabled, no DMA */
950                 { INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
951                 /* Rx 8 bits/char, no auto enable, Rx off */
952                 { RX_CTRL_REG, RCR_CHSIZE_8 },
953                 /* DTR off, Tx 8 bits/char, RTS off, Tx off */
954                 { TX_CTRL_REG, TCR_CHSIZE_8 },
955                 /* special features off */
956                 { AUX2_CTRL_REG, 0 },
957                 { CLK_CTRL_REG, CCR_RTxC_XTAL | CCR_RXCLK_BRG | CCR_TXCLK_BRG },
958                 { DPLL_CTRL_REG, DCR_BRG_ENAB },
959                 /* Start Rx */
960                 { RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
961                 /* Start Tx */
962                 { TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
963                 /* Ext/Stat ints: DCD only */
964                 { INT_CTRL_REG, ICR_ENAB_DCD_INT },
965                 /* Reset Ext/Stat ints */
966                 { COMMAND_REG, CR_EXTSTAT_RESET },
967                 /* ...again */
968                 { COMMAND_REG, CR_EXTSTAT_RESET },
969         };
970 #endif
971         if (!(port->gs.port.flags & ASYNC_INITIALIZED)) {
972                 local_irq_save(flags);
973 #if defined(CONFIG_MVME147_SCC) || defined(CONFIG_MVME162_SCC)
974                 if (MACH_IS_MVME147 || MACH_IS_MVME16x) {
975                         for (i = 0; i < ARRAY_SIZE(mvme_init_tab); ++i)
976                                 SCCwrite(mvme_init_tab[i].reg, mvme_init_tab[i].val);
977                 }
978 #endif
979 #if defined(CONFIG_BVME6000_SCC)
980                 if (MACH_IS_BVME6000) {
981                         for (i = 0; i < ARRAY_SIZE(bvme_init_tab); ++i)
982                                 SCCwrite(bvme_init_tab[i].reg, bvme_init_tab[i].val);
983                 }
984 #endif
985
986                 /* remember status register for detection of DCD and CTS changes */
987                 scc_last_status_reg[channel] = SCCread(STATUS_REG);
988
989                 port->c_dcd = 0;        /* Prevent initial 1->0 interrupt */
990                 scc_setsignals (port, 1,1);
991                 local_irq_restore(flags);
992         }
993
994         tty->driver_data = port;
995         port->gs.port.tty = tty;
996         port->gs.port.count++;
997         retval = gs_init_port(&port->gs);
998         if (retval) {
999                 port->gs.port.count--;
1000                 return retval;
1001         }
1002         port->gs.port.flags |= GS_ACTIVE;
1003         retval = gs_block_til_ready(port, filp);
1004
1005         if (retval) {
1006                 port->gs.port.count--;
1007                 return retval;
1008         }
1009
1010         port->c_dcd = tty_port_carrier_raised(&port->gs.port);
1011
1012         scc_enable_rx_interrupts(port);
1013
1014         return 0;
1015 }
1016
1017
1018 static void scc_throttle (struct tty_struct * tty)
1019 {
1020         struct scc_port *port = tty->driver_data;
1021         unsigned long   flags;
1022         SCC_ACCESS_INIT(port);
1023
1024         if (tty->termios->c_cflag & CRTSCTS) {
1025                 local_irq_save(flags);
1026                 SCCmod(TX_CTRL_REG, ~TCR_RTS, 0);
1027                 local_irq_restore(flags);
1028         }
1029         if (I_IXOFF(tty))
1030                 scc_send_xchar(tty, STOP_CHAR(tty));
1031 }
1032
1033
1034 static void scc_unthrottle (struct tty_struct * tty)
1035 {
1036         struct scc_port *port = tty->driver_data;
1037         unsigned long   flags;
1038         SCC_ACCESS_INIT(port);
1039
1040         if (tty->termios->c_cflag & CRTSCTS) {
1041                 local_irq_save(flags);
1042                 SCCmod(TX_CTRL_REG, 0xff, TCR_RTS);
1043                 local_irq_restore(flags);
1044         }
1045         if (I_IXOFF(tty))
1046                 scc_send_xchar(tty, START_CHAR(tty));
1047 }
1048
1049
1050 static int scc_ioctl(struct tty_struct *tty, struct file *file,
1051                      unsigned int cmd, unsigned long arg)
1052 {
1053         return -ENOIOCTLCMD;
1054 }
1055
1056
1057 static int scc_break_ctl(struct tty_struct *tty, int break_state)
1058 {
1059         struct scc_port *port = tty->driver_data;
1060         unsigned long   flags;
1061         SCC_ACCESS_INIT(port);
1062
1063         local_irq_save(flags);
1064         SCCmod(TX_CTRL_REG, ~TCR_SEND_BREAK, 
1065                         break_state ? TCR_SEND_BREAK : 0);
1066         local_irq_restore(flags);
1067         return 0;
1068 }
1069
1070
1071 /*---------------------------------------------------------------------------
1072  * Serial console stuff...
1073  *--------------------------------------------------------------------------*/
1074
1075 #define scc_delay() do { __asm__ __volatile__ (" nop; nop"); } while (0)
1076
1077 static void scc_ch_write (char ch)
1078 {
1079         volatile char *p = NULL;
1080         
1081 #ifdef CONFIG_MVME147_SCC
1082         if (MACH_IS_MVME147)
1083                 p = (volatile char *)M147_SCC_A_ADDR;
1084 #endif
1085 #ifdef CONFIG_MVME162_SCC
1086         if (MACH_IS_MVME16x)
1087                 p = (volatile char *)MVME_SCC_A_ADDR;
1088 #endif
1089 #ifdef CONFIG_BVME6000_SCC
1090         if (MACH_IS_BVME6000)
1091                 p = (volatile char *)BVME_SCC_A_ADDR;
1092 #endif
1093
1094         do {
1095                 scc_delay();
1096         }
1097         while (!(*p & 4));
1098         scc_delay();
1099         *p = 8;
1100         scc_delay();
1101         *p = ch;
1102 }
1103
1104 /* The console must be locked when we get here. */
1105
1106 static void scc_console_write (struct console *co, const char *str, unsigned count)
1107 {
1108         unsigned long   flags;
1109
1110         local_irq_save(flags);
1111
1112         while (count--)
1113         {
1114                 if (*str == '\n')
1115                         scc_ch_write ('\r');
1116                 scc_ch_write (*str++);
1117         }
1118         local_irq_restore(flags);
1119 }
1120
1121 static struct tty_driver *scc_console_device(struct console *c, int *index)
1122 {
1123         *index = c->index;
1124         return scc_driver;
1125 }
1126
1127 static struct console sercons = {
1128         .name           = "ttyS",
1129         .write          = scc_console_write,
1130         .device         = scc_console_device,
1131         .flags          = CON_PRINTBUFFER,
1132         .index          = -1,
1133 };
1134
1135
1136 static int __init vme_scc_console_init(void)
1137 {
1138         if (vme_brdtype == VME_TYPE_MVME147 ||
1139                         vme_brdtype == VME_TYPE_MVME162 ||
1140                         vme_brdtype == VME_TYPE_MVME172 ||
1141                         vme_brdtype == VME_TYPE_BVME4000 ||
1142                         vme_brdtype == VME_TYPE_BVME6000)
1143                 register_console(&sercons);
1144         return 0;
1145 }
1146 console_initcall(vme_scc_console_init);