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