ia64/linux-2.6.18-xen.hg

view drivers/char/vme_scc.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
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 */
16 #include <linux/module.h>
17 #include <linux/kdev_t.h>
18 #include <asm/io.h>
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/ioport.h>
22 #include <linux/interrupt.h>
23 #include <linux/errno.h>
24 #include <linux/tty.h>
25 #include <linux/tty_flip.h>
26 #include <linux/mm.h>
27 #include <linux/serial.h>
28 #include <linux/fcntl.h>
29 #include <linux/major.h>
30 #include <linux/delay.h>
31 #include <linux/slab.h>
32 #include <linux/miscdevice.h>
33 #include <linux/console.h>
34 #include <linux/init.h>
35 #include <asm/setup.h>
36 #include <asm/bootinfo.h>
38 #ifdef CONFIG_MVME147_SCC
39 #include <asm/mvme147hw.h>
40 #endif
41 #ifdef CONFIG_MVME162_SCC
42 #include <asm/mvme16xhw.h>
43 #endif
44 #ifdef CONFIG_BVME6000_SCC
45 #include <asm/bvme6000hw.h>
46 #endif
48 #include <linux/generic_serial.h>
49 #include "scc.h"
52 #define CHANNEL_A 0
53 #define CHANNEL_B 1
55 #define SCC_MINOR_BASE 64
57 /* Shadows for all SCC write registers */
58 static unsigned char scc_shadow[2][16];
60 /* Location to access for SCC register access delay */
61 static volatile unsigned char *scc_del = NULL;
63 /* To keep track of STATUS_REG state for detection of Ext/Status int source */
64 static unsigned char scc_last_status_reg[2];
66 /***************************** Prototypes *****************************/
68 /* Function prototypes */
69 static void scc_disable_tx_interrupts(void * ptr);
70 static void scc_enable_tx_interrupts(void * ptr);
71 static void scc_disable_rx_interrupts(void * ptr);
72 static void scc_enable_rx_interrupts(void * ptr);
73 static int scc_get_CD(void * ptr);
74 static void scc_shutdown_port(void * ptr);
75 static int scc_set_real_termios(void *ptr);
76 static void scc_hungup(void *ptr);
77 static void scc_close(void *ptr);
78 static int scc_chars_in_buffer(void * ptr);
79 static int scc_open(struct tty_struct * tty, struct file * filp);
80 static int scc_ioctl(struct tty_struct * tty, struct file * filp,
81 unsigned int cmd, unsigned long arg);
82 static void scc_throttle(struct tty_struct *tty);
83 static void scc_unthrottle(struct tty_struct *tty);
84 static irqreturn_t scc_tx_int(int irq, void *data, struct pt_regs *fp);
85 static irqreturn_t scc_rx_int(int irq, void *data, struct pt_regs *fp);
86 static irqreturn_t scc_stat_int(int irq, void *data, struct pt_regs *fp);
87 static irqreturn_t scc_spcond_int(int irq, void *data, struct pt_regs *fp);
88 static void scc_setsignals(struct scc_port *port, int dtr, int rts);
89 static void scc_break_ctl(struct tty_struct *tty, int break_state);
91 static struct tty_driver *scc_driver;
93 struct scc_port scc_ports[2];
95 int scc_initialized = 0;
97 /*---------------------------------------------------------------------------
98 * Interface from generic_serial.c back here
99 *--------------------------------------------------------------------------*/
101 static struct real_driver scc_real_driver = {
102 scc_disable_tx_interrupts,
103 scc_enable_tx_interrupts,
104 scc_disable_rx_interrupts,
105 scc_enable_rx_interrupts,
106 scc_get_CD,
107 scc_shutdown_port,
108 scc_set_real_termios,
109 scc_chars_in_buffer,
110 scc_close,
111 scc_hungup,
112 NULL
113 };
116 static struct tty_operations scc_ops = {
117 .open = scc_open,
118 .close = gs_close,
119 .write = gs_write,
120 .put_char = gs_put_char,
121 .flush_chars = gs_flush_chars,
122 .write_room = gs_write_room,
123 .chars_in_buffer = gs_chars_in_buffer,
124 .flush_buffer = gs_flush_buffer,
125 .ioctl = scc_ioctl,
126 .throttle = scc_throttle,
127 .unthrottle = scc_unthrottle,
128 .set_termios = gs_set_termios,
129 .stop = gs_stop,
130 .start = gs_start,
131 .hangup = gs_hangup,
132 .break_ctl = scc_break_ctl,
133 };
135 /*----------------------------------------------------------------------------
136 * vme_scc_init() and support functions
137 *---------------------------------------------------------------------------*/
139 static int scc_init_drivers(void)
140 {
141 int error;
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->flags = TTY_DRIVER_REAL_RAW;
157 tty_set_operations(scc_driver, &scc_ops);
159 if ((error = tty_register_driver(scc_driver))) {
160 printk(KERN_ERR "scc: Couldn't register scc driver, error = %d\n",
161 error);
162 put_tty_driver(scc_driver);
163 return 1;
164 }
166 return 0;
167 }
170 /* ports[] array is indexed by line no (i.e. [0] for ttyS0, [1] for ttyS1).
171 */
173 static void scc_init_portstructs(void)
174 {
175 struct scc_port *port;
176 int i;
178 for (i = 0; i < 2; i++) {
179 port = scc_ports + i;
180 port->gs.magic = SCC_MAGIC;
181 port->gs.close_delay = HZ/2;
182 port->gs.closing_wait = 30 * HZ;
183 port->gs.rd = &scc_real_driver;
184 #ifdef NEW_WRITE_LOCKING
185 port->gs.port_write_mutex = MUTEX;
186 #endif
187 init_waitqueue_head(&port->gs.open_wait);
188 init_waitqueue_head(&port->gs.close_wait);
189 }
190 }
193 #ifdef CONFIG_MVME147_SCC
194 static int mvme147_scc_init(void)
195 {
196 struct scc_port *port;
198 printk(KERN_INFO "SCC: MVME147 Serial Driver\n");
199 /* Init channel A */
200 port = &scc_ports[0];
201 port->channel = CHANNEL_A;
202 port->ctrlp = (volatile unsigned char *)M147_SCC_A_ADDR;
203 port->datap = port->ctrlp + 1;
204 port->port_a = &scc_ports[0];
205 port->port_b = &scc_ports[1];
206 request_irq(MVME147_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
207 "SCC-A TX", port);
208 request_irq(MVME147_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
209 "SCC-A status", port);
210 request_irq(MVME147_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
211 "SCC-A RX", port);
212 request_irq(MVME147_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
213 "SCC-A special cond", port);
214 {
215 SCC_ACCESS_INIT(port);
217 /* disable interrupts for this channel */
218 SCCwrite(INT_AND_DMA_REG, 0);
219 /* Set the interrupt vector */
220 SCCwrite(INT_VECTOR_REG, MVME147_IRQ_SCC_BASE);
221 /* Interrupt parameters: vector includes status, status low */
222 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
223 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
224 }
226 /* Init channel B */
227 port = &scc_ports[1];
228 port->channel = CHANNEL_B;
229 port->ctrlp = (volatile unsigned char *)M147_SCC_B_ADDR;
230 port->datap = port->ctrlp + 1;
231 port->port_a = &scc_ports[0];
232 port->port_b = &scc_ports[1];
233 request_irq(MVME147_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
234 "SCC-B TX", port);
235 request_irq(MVME147_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
236 "SCC-B status", port);
237 request_irq(MVME147_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
238 "SCC-B RX", port);
239 request_irq(MVME147_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
240 "SCC-B special cond", port);
241 {
242 SCC_ACCESS_INIT(port);
244 /* disable interrupts for this channel */
245 SCCwrite(INT_AND_DMA_REG, 0);
246 }
248 /* Ensure interrupts are enabled in the PCC chip */
249 m147_pcc->serial_cntrl=PCC_LEVEL_SERIAL|PCC_INT_ENAB;
251 /* Initialise the tty driver structures and register */
252 scc_init_portstructs();
253 scc_init_drivers();
255 return 0;
256 }
257 #endif
260 #ifdef CONFIG_MVME162_SCC
261 static int mvme162_scc_init(void)
262 {
263 struct scc_port *port;
265 if (!(mvme16x_config & MVME16x_CONFIG_GOT_SCCA))
266 return (-ENODEV);
268 printk(KERN_INFO "SCC: MVME162 Serial Driver\n");
269 /* Init channel A */
270 port = &scc_ports[0];
271 port->channel = CHANNEL_A;
272 port->ctrlp = (volatile unsigned char *)MVME_SCC_A_ADDR;
273 port->datap = port->ctrlp + 2;
274 port->port_a = &scc_ports[0];
275 port->port_b = &scc_ports[1];
276 request_irq(MVME162_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
277 "SCC-A TX", port);
278 request_irq(MVME162_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
279 "SCC-A status", port);
280 request_irq(MVME162_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
281 "SCC-A RX", port);
282 request_irq(MVME162_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
283 "SCC-A special cond", port);
284 {
285 SCC_ACCESS_INIT(port);
287 /* disable interrupts for this channel */
288 SCCwrite(INT_AND_DMA_REG, 0);
289 /* Set the interrupt vector */
290 SCCwrite(INT_VECTOR_REG, MVME162_IRQ_SCC_BASE);
291 /* Interrupt parameters: vector includes status, status low */
292 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
293 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
294 }
296 /* Init channel B */
297 port = &scc_ports[1];
298 port->channel = CHANNEL_B;
299 port->ctrlp = (volatile unsigned char *)MVME_SCC_B_ADDR;
300 port->datap = port->ctrlp + 2;
301 port->port_a = &scc_ports[0];
302 port->port_b = &scc_ports[1];
303 request_irq(MVME162_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
304 "SCC-B TX", port);
305 request_irq(MVME162_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
306 "SCC-B status", port);
307 request_irq(MVME162_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
308 "SCC-B RX", port);
309 request_irq(MVME162_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
310 "SCC-B special cond", port);
312 {
313 SCC_ACCESS_INIT(port); /* Either channel will do */
315 /* disable interrupts for this channel */
316 SCCwrite(INT_AND_DMA_REG, 0);
317 }
319 /* Ensure interrupts are enabled in the MC2 chip */
320 *(volatile char *)0xfff4201d = 0x14;
322 /* Initialise the tty driver structures and register */
323 scc_init_portstructs();
324 scc_init_drivers();
326 return 0;
327 }
328 #endif
331 #ifdef CONFIG_BVME6000_SCC
332 static int bvme6000_scc_init(void)
333 {
334 struct scc_port *port;
336 printk(KERN_INFO "SCC: BVME6000 Serial Driver\n");
337 /* Init channel A */
338 port = &scc_ports[0];
339 port->channel = CHANNEL_A;
340 port->ctrlp = (volatile unsigned char *)BVME_SCC_A_ADDR;
341 port->datap = port->ctrlp + 4;
342 port->port_a = &scc_ports[0];
343 port->port_b = &scc_ports[1];
344 request_irq(BVME_IRQ_SCCA_TX, scc_tx_int, IRQF_DISABLED,
345 "SCC-A TX", port);
346 request_irq(BVME_IRQ_SCCA_STAT, scc_stat_int, IRQF_DISABLED,
347 "SCC-A status", port);
348 request_irq(BVME_IRQ_SCCA_RX, scc_rx_int, IRQF_DISABLED,
349 "SCC-A RX", port);
350 request_irq(BVME_IRQ_SCCA_SPCOND, scc_spcond_int, IRQF_DISABLED,
351 "SCC-A special cond", port);
352 {
353 SCC_ACCESS_INIT(port);
355 /* disable interrupts for this channel */
356 SCCwrite(INT_AND_DMA_REG, 0);
357 /* Set the interrupt vector */
358 SCCwrite(INT_VECTOR_REG, BVME_IRQ_SCC_BASE);
359 /* Interrupt parameters: vector includes status, status low */
360 SCCwrite(MASTER_INT_CTRL, MIC_VEC_INCL_STAT);
361 SCCmod(MASTER_INT_CTRL, 0xff, MIC_MASTER_INT_ENAB);
362 }
364 /* Init channel B */
365 port = &scc_ports[1];
366 port->channel = CHANNEL_B;
367 port->ctrlp = (volatile unsigned char *)BVME_SCC_B_ADDR;
368 port->datap = port->ctrlp + 4;
369 port->port_a = &scc_ports[0];
370 port->port_b = &scc_ports[1];
371 request_irq(BVME_IRQ_SCCB_TX, scc_tx_int, IRQF_DISABLED,
372 "SCC-B TX", port);
373 request_irq(BVME_IRQ_SCCB_STAT, scc_stat_int, IRQF_DISABLED,
374 "SCC-B status", port);
375 request_irq(BVME_IRQ_SCCB_RX, scc_rx_int, IRQF_DISABLED,
376 "SCC-B RX", port);
377 request_irq(BVME_IRQ_SCCB_SPCOND, scc_spcond_int, IRQF_DISABLED,
378 "SCC-B special cond", port);
380 {
381 SCC_ACCESS_INIT(port); /* Either channel will do */
383 /* disable interrupts for this channel */
384 SCCwrite(INT_AND_DMA_REG, 0);
385 }
387 /* Initialise the tty driver structures and register */
388 scc_init_portstructs();
389 scc_init_drivers();
391 return 0;
392 }
393 #endif
396 static int vme_scc_init(void)
397 {
398 int res = -ENODEV;
400 #ifdef CONFIG_MVME147_SCC
401 if (MACH_IS_MVME147)
402 res = mvme147_scc_init();
403 #endif
404 #ifdef CONFIG_MVME162_SCC
405 if (MACH_IS_MVME16x)
406 res = mvme162_scc_init();
407 #endif
408 #ifdef CONFIG_BVME6000_SCC
409 if (MACH_IS_BVME6000)
410 res = bvme6000_scc_init();
411 #endif
412 return res;
413 }
415 module_init(vme_scc_init);
418 /*---------------------------------------------------------------------------
419 * Interrupt handlers
420 *--------------------------------------------------------------------------*/
422 static irqreturn_t scc_rx_int(int irq, void *data, struct pt_regs *fp)
423 {
424 unsigned char ch;
425 struct scc_port *port = data;
426 struct tty_struct *tty = port->gs.tty;
427 SCC_ACCESS_INIT(port);
429 ch = SCCread_NB(RX_DATA_REG);
430 if (!tty) {
431 printk(KERN_WARNING "scc_rx_int with NULL tty!\n");
432 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
433 return IRQ_HANDLED;
434 }
435 tty_insert_flip_char(tty, ch, 0);
437 /* Check if another character is already ready; in that case, the
438 * spcond_int() function must be used, because this character may have an
439 * error condition that isn't signalled by the interrupt vector used!
440 */
441 if (SCCread(INT_PENDING_REG) &
442 (port->channel == CHANNEL_A ? IPR_A_RX : IPR_B_RX)) {
443 scc_spcond_int (irq, data, fp);
444 return IRQ_HANDLED;
445 }
447 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
449 tty_flip_buffer_push(tty);
450 return IRQ_HANDLED;
451 }
454 static irqreturn_t scc_spcond_int(int irq, void *data, struct pt_regs *fp)
455 {
456 struct scc_port *port = data;
457 struct tty_struct *tty = port->gs.tty;
458 unsigned char stat, ch, err;
459 int int_pending_mask = port->channel == CHANNEL_A ?
460 IPR_A_RX : IPR_B_RX;
461 SCC_ACCESS_INIT(port);
463 if (!tty) {
464 printk(KERN_WARNING "scc_spcond_int with NULL tty!\n");
465 SCCwrite(COMMAND_REG, CR_ERROR_RESET);
466 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
467 return IRQ_HANDLED;
468 }
469 do {
470 stat = SCCread(SPCOND_STATUS_REG);
471 ch = SCCread_NB(RX_DATA_REG);
473 if (stat & SCSR_RX_OVERRUN)
474 err = TTY_OVERRUN;
475 else if (stat & SCSR_PARITY_ERR)
476 err = TTY_PARITY;
477 else if (stat & SCSR_CRC_FRAME_ERR)
478 err = TTY_FRAME;
479 else
480 err = 0;
482 tty_insert_flip_char(tty, ch, err);
484 /* ++TeSche: *All* errors have to be cleared manually,
485 * else the condition persists for the next chars
486 */
487 if (err)
488 SCCwrite(COMMAND_REG, CR_ERROR_RESET);
490 } while(SCCread(INT_PENDING_REG) & int_pending_mask);
492 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
494 tty_flip_buffer_push(tty);
495 return IRQ_HANDLED;
496 }
499 static irqreturn_t scc_tx_int(int irq, void *data, struct pt_regs *fp)
500 {
501 struct scc_port *port = data;
502 SCC_ACCESS_INIT(port);
504 if (!port->gs.tty) {
505 printk(KERN_WARNING "scc_tx_int with NULL tty!\n");
506 SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
507 SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET);
508 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
509 return IRQ_HANDLED;
510 }
511 while ((SCCread_NB(STATUS_REG) & SR_TX_BUF_EMPTY)) {
512 if (port->x_char) {
513 SCCwrite(TX_DATA_REG, port->x_char);
514 port->x_char = 0;
515 }
516 else if ((port->gs.xmit_cnt <= 0) || port->gs.tty->stopped ||
517 port->gs.tty->hw_stopped)
518 break;
519 else {
520 SCCwrite(TX_DATA_REG, port->gs.xmit_buf[port->gs.xmit_tail++]);
521 port->gs.xmit_tail = port->gs.xmit_tail & (SERIAL_XMIT_SIZE-1);
522 if (--port->gs.xmit_cnt <= 0)
523 break;
524 }
525 }
526 if ((port->gs.xmit_cnt <= 0) || port->gs.tty->stopped ||
527 port->gs.tty->hw_stopped) {
528 /* disable tx interrupts */
529 SCCmod (INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
530 SCCwrite(COMMAND_REG, CR_TX_PENDING_RESET); /* disable tx_int on next tx underrun? */
531 port->gs.flags &= ~GS_TX_INTEN;
532 }
533 if (port->gs.tty && port->gs.xmit_cnt <= port->gs.wakeup_chars)
534 tty_wakeup(port->gs.tty);
536 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
537 return IRQ_HANDLED;
538 }
541 static irqreturn_t scc_stat_int(int irq, void *data, struct pt_regs *fp)
542 {
543 struct scc_port *port = data;
544 unsigned channel = port->channel;
545 unsigned char last_sr, sr, changed;
546 SCC_ACCESS_INIT(port);
548 last_sr = scc_last_status_reg[channel];
549 sr = scc_last_status_reg[channel] = SCCread_NB(STATUS_REG);
550 changed = last_sr ^ sr;
552 if (changed & SR_DCD) {
553 port->c_dcd = !!(sr & SR_DCD);
554 if (!(port->gs.flags & ASYNC_CHECK_CD))
555 ; /* Don't report DCD changes */
556 else if (port->c_dcd) {
557 wake_up_interruptible(&port->gs.open_wait);
558 }
559 else {
560 if (port->gs.tty)
561 tty_hangup (port->gs.tty);
562 }
563 }
564 SCCwrite(COMMAND_REG, CR_EXTSTAT_RESET);
565 SCCwrite_NB(COMMAND_REG, CR_HIGHEST_IUS_RESET);
566 return IRQ_HANDLED;
567 }
570 /*---------------------------------------------------------------------------
571 * generic_serial.c callback funtions
572 *--------------------------------------------------------------------------*/
574 static void scc_disable_tx_interrupts(void *ptr)
575 {
576 struct scc_port *port = ptr;
577 unsigned long flags;
578 SCC_ACCESS_INIT(port);
580 local_irq_save(flags);
581 SCCmod(INT_AND_DMA_REG, ~IDR_TX_INT_ENAB, 0);
582 port->gs.flags &= ~GS_TX_INTEN;
583 local_irq_restore(flags);
584 }
587 static void scc_enable_tx_interrupts(void *ptr)
588 {
589 struct scc_port *port = ptr;
590 unsigned long flags;
591 SCC_ACCESS_INIT(port);
593 local_irq_save(flags);
594 SCCmod(INT_AND_DMA_REG, 0xff, IDR_TX_INT_ENAB);
595 /* restart the transmitter */
596 scc_tx_int (0, port, 0);
597 local_irq_restore(flags);
598 }
601 static void scc_disable_rx_interrupts(void *ptr)
602 {
603 struct scc_port *port = ptr;
604 unsigned long flags;
605 SCC_ACCESS_INIT(port);
607 local_irq_save(flags);
608 SCCmod(INT_AND_DMA_REG,
609 ~(IDR_RX_INT_MASK|IDR_PARERR_AS_SPCOND|IDR_EXTSTAT_INT_ENAB), 0);
610 local_irq_restore(flags);
611 }
614 static void scc_enable_rx_interrupts(void *ptr)
615 {
616 struct scc_port *port = ptr;
617 unsigned long flags;
618 SCC_ACCESS_INIT(port);
620 local_irq_save(flags);
621 SCCmod(INT_AND_DMA_REG, 0xff,
622 IDR_EXTSTAT_INT_ENAB|IDR_PARERR_AS_SPCOND|IDR_RX_INT_ALL);
623 local_irq_restore(flags);
624 }
627 static int scc_get_CD(void *ptr)
628 {
629 struct scc_port *port = ptr;
630 unsigned channel = port->channel;
632 return !!(scc_last_status_reg[channel] & SR_DCD);
633 }
636 static void scc_shutdown_port(void *ptr)
637 {
638 struct scc_port *port = ptr;
640 port->gs.flags &= ~ GS_ACTIVE;
641 if (port->gs.tty && port->gs.tty->termios->c_cflag & HUPCL) {
642 scc_setsignals (port, 0, 0);
643 }
644 }
647 static int scc_set_real_termios (void *ptr)
648 {
649 /* the SCC has char sizes 5,7,6,8 in that order! */
650 static int chsize_map[4] = { 0, 2, 1, 3 };
651 unsigned cflag, baud, chsize, channel, brgval = 0;
652 unsigned long flags;
653 struct scc_port *port = ptr;
654 SCC_ACCESS_INIT(port);
656 if (!port->gs.tty || !port->gs.tty->termios) return 0;
658 channel = port->channel;
660 if (channel == CHANNEL_A)
661 return 0; /* Settings controlled by boot PROM */
663 cflag = port->gs.tty->termios->c_cflag;
664 baud = port->gs.baud;
665 chsize = (cflag & CSIZE) >> 4;
667 if (baud == 0) {
668 /* speed == 0 -> drop DTR */
669 local_irq_save(flags);
670 SCCmod(TX_CTRL_REG, ~TCR_DTR, 0);
671 local_irq_restore(flags);
672 return 0;
673 }
674 else if ((MACH_IS_MVME16x && (baud < 50 || baud > 38400)) ||
675 (MACH_IS_MVME147 && (baud < 50 || baud > 19200)) ||
676 (MACH_IS_BVME6000 &&(baud < 50 || baud > 76800))) {
677 printk(KERN_NOTICE "SCC: Bad speed requested, %d\n", baud);
678 return 0;
679 }
681 if (cflag & CLOCAL)
682 port->gs.flags &= ~ASYNC_CHECK_CD;
683 else
684 port->gs.flags |= ASYNC_CHECK_CD;
686 #ifdef CONFIG_MVME147_SCC
687 if (MACH_IS_MVME147)
688 brgval = (M147_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
689 #endif
690 #ifdef CONFIG_MVME162_SCC
691 if (MACH_IS_MVME16x)
692 brgval = (MVME_SCC_PCLK + baud/2) / (16 * 2 * baud) - 2;
693 #endif
694 #ifdef CONFIG_BVME6000_SCC
695 if (MACH_IS_BVME6000)
696 brgval = (BVME_SCC_RTxC + baud/2) / (16 * 2 * baud) - 2;
697 #endif
698 /* Now we have all parameters and can go to set them: */
699 local_irq_save(flags);
701 /* receiver's character size and auto-enables */
702 SCCmod(RX_CTRL_REG, ~(RCR_CHSIZE_MASK|RCR_AUTO_ENAB_MODE),
703 (chsize_map[chsize] << 6) |
704 ((cflag & CRTSCTS) ? RCR_AUTO_ENAB_MODE : 0));
705 /* parity and stop bits (both, Tx and Rx), clock mode never changes */
706 SCCmod (AUX1_CTRL_REG,
707 ~(A1CR_PARITY_MASK | A1CR_MODE_MASK),
708 ((cflag & PARENB
709 ? (cflag & PARODD ? A1CR_PARITY_ODD : A1CR_PARITY_EVEN)
710 : A1CR_PARITY_NONE)
711 | (cflag & CSTOPB ? A1CR_MODE_ASYNC_2 : A1CR_MODE_ASYNC_1)));
712 /* sender's character size, set DTR for valid baud rate */
713 SCCmod(TX_CTRL_REG, ~TCR_CHSIZE_MASK, chsize_map[chsize] << 5 | TCR_DTR);
714 /* clock sources never change */
715 /* disable BRG before changing the value */
716 SCCmod(DPLL_CTRL_REG, ~DCR_BRG_ENAB, 0);
717 /* BRG value */
718 SCCwrite(TIMER_LOW_REG, brgval & 0xff);
719 SCCwrite(TIMER_HIGH_REG, (brgval >> 8) & 0xff);
720 /* BRG enable, and clock source never changes */
721 SCCmod(DPLL_CTRL_REG, 0xff, DCR_BRG_ENAB);
723 local_irq_restore(flags);
725 return 0;
726 }
729 static int scc_chars_in_buffer (void *ptr)
730 {
731 struct scc_port *port = ptr;
732 SCC_ACCESS_INIT(port);
734 return (SCCread (SPCOND_STATUS_REG) & SCSR_ALL_SENT) ? 0 : 1;
735 }
738 /* Comment taken from sx.c (2.4.0):
739 I haven't the foggiest why the decrement use count has to happen
740 here. The whole linux serial drivers stuff needs to be redesigned.
741 My guess is that this is a hack to minimize the impact of a bug
742 elsewhere. Thinking about it some more. (try it sometime) Try
743 running minicom on a serial port that is driven by a modularized
744 driver. Have the modem hangup. Then remove the driver module. Then
745 exit minicom. I expect an "oops". -- REW */
747 static void scc_hungup(void *ptr)
748 {
749 scc_disable_tx_interrupts(ptr);
750 scc_disable_rx_interrupts(ptr);
751 }
754 static void scc_close(void *ptr)
755 {
756 scc_disable_tx_interrupts(ptr);
757 scc_disable_rx_interrupts(ptr);
758 }
761 /*---------------------------------------------------------------------------
762 * Internal support functions
763 *--------------------------------------------------------------------------*/
765 static void scc_setsignals(struct scc_port *port, int dtr, int rts)
766 {
767 unsigned long flags;
768 unsigned char t;
769 SCC_ACCESS_INIT(port);
771 local_irq_save(flags);
772 t = SCCread(TX_CTRL_REG);
773 if (dtr >= 0) t = dtr? (t | TCR_DTR): (t & ~TCR_DTR);
774 if (rts >= 0) t = rts? (t | TCR_RTS): (t & ~TCR_RTS);
775 SCCwrite(TX_CTRL_REG, t);
776 local_irq_restore(flags);
777 }
780 static void scc_send_xchar(struct tty_struct *tty, char ch)
781 {
782 struct scc_port *port = (struct scc_port *)tty->driver_data;
784 port->x_char = ch;
785 if (ch)
786 scc_enable_tx_interrupts(port);
787 }
790 /*---------------------------------------------------------------------------
791 * Driver entrypoints referenced from above
792 *--------------------------------------------------------------------------*/
794 static int scc_open (struct tty_struct * tty, struct file * filp)
795 {
796 int line = tty->index;
797 int retval;
798 struct scc_port *port = &scc_ports[line];
799 int i, channel = port->channel;
800 unsigned long flags;
801 SCC_ACCESS_INIT(port);
802 #if defined(CONFIG_MVME162_SCC) || defined(CONFIG_MVME147_SCC)
803 static const struct {
804 unsigned reg, val;
805 } mvme_init_tab[] = {
806 /* Values for MVME162 and MVME147 */
807 /* no parity, 1 stop bit, async, 1:16 */
808 { AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
809 /* parity error is special cond, ints disabled, no DMA */
810 { INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
811 /* Rx 8 bits/char, no auto enable, Rx off */
812 { RX_CTRL_REG, RCR_CHSIZE_8 },
813 /* DTR off, Tx 8 bits/char, RTS off, Tx off */
814 { TX_CTRL_REG, TCR_CHSIZE_8 },
815 /* special features off */
816 { AUX2_CTRL_REG, 0 },
817 { CLK_CTRL_REG, CCR_RXCLK_BRG | CCR_TXCLK_BRG },
818 { DPLL_CTRL_REG, DCR_BRG_ENAB | DCR_BRG_USE_PCLK },
819 /* Start Rx */
820 { RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
821 /* Start Tx */
822 { TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
823 /* Ext/Stat ints: DCD only */
824 { INT_CTRL_REG, ICR_ENAB_DCD_INT },
825 /* Reset Ext/Stat ints */
826 { COMMAND_REG, CR_EXTSTAT_RESET },
827 /* ...again */
828 { COMMAND_REG, CR_EXTSTAT_RESET },
829 };
830 #endif
831 #if defined(CONFIG_BVME6000_SCC)
832 static const struct {
833 unsigned reg, val;
834 } bvme_init_tab[] = {
835 /* Values for BVME6000 */
836 /* no parity, 1 stop bit, async, 1:16 */
837 { AUX1_CTRL_REG, A1CR_PARITY_NONE|A1CR_MODE_ASYNC_1|A1CR_CLKMODE_x16 },
838 /* parity error is special cond, ints disabled, no DMA */
839 { INT_AND_DMA_REG, IDR_PARERR_AS_SPCOND | IDR_RX_INT_DISAB },
840 /* Rx 8 bits/char, no auto enable, Rx off */
841 { RX_CTRL_REG, RCR_CHSIZE_8 },
842 /* DTR off, Tx 8 bits/char, RTS off, Tx off */
843 { TX_CTRL_REG, TCR_CHSIZE_8 },
844 /* special features off */
845 { AUX2_CTRL_REG, 0 },
846 { CLK_CTRL_REG, CCR_RTxC_XTAL | CCR_RXCLK_BRG | CCR_TXCLK_BRG },
847 { DPLL_CTRL_REG, DCR_BRG_ENAB },
848 /* Start Rx */
849 { RX_CTRL_REG, RCR_RX_ENAB | RCR_CHSIZE_8 },
850 /* Start Tx */
851 { TX_CTRL_REG, TCR_TX_ENAB | TCR_RTS | TCR_DTR | TCR_CHSIZE_8 },
852 /* Ext/Stat ints: DCD only */
853 { INT_CTRL_REG, ICR_ENAB_DCD_INT },
854 /* Reset Ext/Stat ints */
855 { COMMAND_REG, CR_EXTSTAT_RESET },
856 /* ...again */
857 { COMMAND_REG, CR_EXTSTAT_RESET },
858 };
859 #endif
860 if (!(port->gs.flags & ASYNC_INITIALIZED)) {
861 local_irq_save(flags);
862 #if defined(CONFIG_MVME147_SCC) || defined(CONFIG_MVME162_SCC)
863 if (MACH_IS_MVME147 || MACH_IS_MVME16x) {
864 for (i = 0; i < ARRAY_SIZE(mvme_init_tab); ++i)
865 SCCwrite(mvme_init_tab[i].reg, mvme_init_tab[i].val);
866 }
867 #endif
868 #if defined(CONFIG_BVME6000_SCC)
869 if (MACH_IS_BVME6000) {
870 for (i = 0; i < ARRAY_SIZE(bvme_init_tab); ++i)
871 SCCwrite(bvme_init_tab[i].reg, bvme_init_tab[i].val);
872 }
873 #endif
875 /* remember status register for detection of DCD and CTS changes */
876 scc_last_status_reg[channel] = SCCread(STATUS_REG);
878 port->c_dcd = 0; /* Prevent initial 1->0 interrupt */
879 scc_setsignals (port, 1,1);
880 local_irq_restore(flags);
881 }
883 tty->driver_data = port;
884 port->gs.tty = tty;
885 port->gs.count++;
886 retval = gs_init_port(&port->gs);
887 if (retval) {
888 port->gs.count--;
889 return retval;
890 }
891 port->gs.flags |= GS_ACTIVE;
892 retval = gs_block_til_ready(port, filp);
894 if (retval) {
895 port->gs.count--;
896 return retval;
897 }
899 port->c_dcd = scc_get_CD (port);
901 scc_enable_rx_interrupts(port);
903 return 0;
904 }
907 static void scc_throttle (struct tty_struct * tty)
908 {
909 struct scc_port *port = (struct scc_port *)tty->driver_data;
910 unsigned long flags;
911 SCC_ACCESS_INIT(port);
913 if (tty->termios->c_cflag & CRTSCTS) {
914 local_irq_save(flags);
915 SCCmod(TX_CTRL_REG, ~TCR_RTS, 0);
916 local_irq_restore(flags);
917 }
918 if (I_IXOFF(tty))
919 scc_send_xchar(tty, STOP_CHAR(tty));
920 }
923 static void scc_unthrottle (struct tty_struct * tty)
924 {
925 struct scc_port *port = (struct scc_port *)tty->driver_data;
926 unsigned long flags;
927 SCC_ACCESS_INIT(port);
929 if (tty->termios->c_cflag & CRTSCTS) {
930 local_irq_save(flags);
931 SCCmod(TX_CTRL_REG, 0xff, TCR_RTS);
932 local_irq_restore(flags);
933 }
934 if (I_IXOFF(tty))
935 scc_send_xchar(tty, START_CHAR(tty));
936 }
939 static int scc_ioctl(struct tty_struct *tty, struct file *file,
940 unsigned int cmd, unsigned long arg)
941 {
942 return -ENOIOCTLCMD;
943 }
946 static void scc_break_ctl(struct tty_struct *tty, int break_state)
947 {
948 struct scc_port *port = (struct scc_port *)tty->driver_data;
949 unsigned long flags;
950 SCC_ACCESS_INIT(port);
952 local_irq_save(flags);
953 SCCmod(TX_CTRL_REG, ~TCR_SEND_BREAK,
954 break_state ? TCR_SEND_BREAK : 0);
955 local_irq_restore(flags);
956 }
959 /*---------------------------------------------------------------------------
960 * Serial console stuff...
961 *--------------------------------------------------------------------------*/
963 #define scc_delay() do { __asm__ __volatile__ (" nop; nop"); } while (0)
965 static void scc_ch_write (char ch)
966 {
967 volatile char *p = NULL;
969 #ifdef CONFIG_MVME147_SCC
970 if (MACH_IS_MVME147)
971 p = (volatile char *)M147_SCC_A_ADDR;
972 #endif
973 #ifdef CONFIG_MVME162_SCC
974 if (MACH_IS_MVME16x)
975 p = (volatile char *)MVME_SCC_A_ADDR;
976 #endif
977 #ifdef CONFIG_BVME6000_SCC
978 if (MACH_IS_BVME6000)
979 p = (volatile char *)BVME_SCC_A_ADDR;
980 #endif
982 do {
983 scc_delay();
984 }
985 while (!(*p & 4));
986 scc_delay();
987 *p = 8;
988 scc_delay();
989 *p = ch;
990 }
992 /* The console must be locked when we get here. */
994 static void scc_console_write (struct console *co, const char *str, unsigned count)
995 {
996 unsigned long flags;
998 local_irq_save(flags);
1000 while (count--)
1002 if (*str == '\n')
1003 scc_ch_write ('\r');
1004 scc_ch_write (*str++);
1006 local_irq_restore(flags);
1009 static struct tty_driver *scc_console_device(struct console *c, int *index)
1011 *index = c->index;
1012 return scc_driver;
1016 static int __init scc_console_setup(struct console *co, char *options)
1018 return 0;
1022 static struct console sercons = {
1023 .name = "ttyS",
1024 .write = scc_console_write,
1025 .device = scc_console_device,
1026 .setup = scc_console_setup,
1027 .flags = CON_PRINTBUFFER,
1028 .index = -1,
1029 };
1032 static int __init vme_scc_console_init(void)
1034 if (vme_brdtype == VME_TYPE_MVME147 ||
1035 vme_brdtype == VME_TYPE_MVME162 ||
1036 vme_brdtype == VME_TYPE_MVME172 ||
1037 vme_brdtype == VME_TYPE_BVME4000 ||
1038 vme_brdtype == VME_TYPE_BVME6000)
1039 register_console(&sercons);
1040 return 0;
1042 console_initcall(vme_scc_console_init);