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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/serial/au1x00_uart.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/serial/au1x00_uart.c')
-rw-r--r--drivers/serial/au1x00_uart.c1312
1 files changed, 1312 insertions, 0 deletions
diff --git a/drivers/serial/au1x00_uart.c b/drivers/serial/au1x00_uart.c
new file mode 100644
index 000000000000..b6d3d5034940
--- /dev/null
+++ b/drivers/serial/au1x00_uart.c
@@ -0,0 +1,1312 @@
1/*
2 * Driver for 8250/16550-type serial ports
3 *
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5 *
6 * Copyright (C) 2001 Russell King.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * A note about mapbase / membase
14 *
15 * mapbase is the physical address of the IO port. Currently, we don't
16 * support this very well, and it may well be dropped from this driver
17 * in future. As such, mapbase should be NULL.
18 *
19 * membase is an 'ioremapped' cookie. This is compatible with the old
20 * serial.c driver, and is currently the preferred form.
21 */
22#include <linux/config.h>
23#include <linux/module.h>
24#include <linux/tty.h>
25#include <linux/ioport.h>
26#include <linux/init.h>
27#include <linux/console.h>
28#include <linux/sysrq.h>
29#include <linux/serial.h>
30#include <linux/serialP.h>
31#include <linux/delay.h>
32
33#include <asm/serial.h>
34#include <asm/io.h>
35#include <asm/irq.h>
36#include <asm/mach-au1x00/au1000.h>
37
38#if defined(CONFIG_SERIAL_AU1X00_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
39#define SUPPORT_SYSRQ
40#endif
41
42#include <linux/serial_core.h>
43#include "8250.h"
44
45/*
46 * Debugging.
47 */
48#if 0
49#define DEBUG_AUTOCONF(fmt...) printk(fmt)
50#else
51#define DEBUG_AUTOCONF(fmt...) do { } while (0)
52#endif
53
54#if 0
55#define DEBUG_INTR(fmt...) printk(fmt)
56#else
57#define DEBUG_INTR(fmt...) do { } while (0)
58#endif
59
60#define PASS_LIMIT 256
61
62/*
63 * We default to IRQ0 for the "no irq" hack. Some
64 * machine types want others as well - they're free
65 * to redefine this in their header file.
66 */
67#define is_real_interrupt(irq) ((irq) != 0)
68
69static struct old_serial_port old_serial_port[] = {
70 { .baud_base = 0,
71 .iomem_base = (u8 *)UART0_ADDR,
72 .irq = AU1000_UART0_INT,
73 .flags = STD_COM_FLAGS,
74 .iomem_reg_shift = 2,
75 }, {
76 .baud_base = 0,
77 .iomem_base = (u8 *)UART1_ADDR,
78 .irq = AU1000_UART1_INT,
79 .flags = STD_COM_FLAGS,
80 .iomem_reg_shift = 2
81 }, {
82 .baud_base = 0,
83 .iomem_base = (u8 *)UART2_ADDR,
84 .irq = AU1000_UART2_INT,
85 .flags = STD_COM_FLAGS,
86 .iomem_reg_shift = 2
87 }, {
88 .baud_base = 0,
89 .iomem_base = (u8 *)UART3_ADDR,
90 .irq = AU1000_UART3_INT,
91 .flags = STD_COM_FLAGS,
92 .iomem_reg_shift = 2
93 }
94};
95
96#define UART_NR ARRAY_SIZE(old_serial_port)
97
98struct uart_8250_port {
99 struct uart_port port;
100 struct timer_list timer; /* "no irq" timer */
101 struct list_head list; /* ports on this IRQ */
102 unsigned short rev;
103 unsigned char acr;
104 unsigned char ier;
105 unsigned char lcr;
106 unsigned char mcr_mask; /* mask of user bits */
107 unsigned char mcr_force; /* mask of forced bits */
108 unsigned char lsr_break_flag;
109
110 /*
111 * We provide a per-port pm hook.
112 */
113 void (*pm)(struct uart_port *port,
114 unsigned int state, unsigned int old);
115};
116
117struct irq_info {
118 spinlock_t lock;
119 struct list_head *head;
120};
121
122static struct irq_info irq_lists[NR_IRQS];
123
124/*
125 * Here we define the default xmit fifo size used for each type of UART.
126 */
127static const struct serial_uart_config uart_config[PORT_MAX_8250+1] = {
128 { "unknown", 1, 0 },
129 { "8250", 1, 0 },
130 { "16450", 1, 0 },
131 { "16550", 1, 0 },
132 /* PORT_16550A */
133 { "AU1X00_UART",16, UART_CLEAR_FIFO | UART_USE_FIFO },
134};
135
136static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset)
137{
138 return au_readl((unsigned long)up->port.membase + offset);
139}
140
141static _INLINE_ void
142serial_out(struct uart_8250_port *up, int offset, int value)
143{
144 au_writel(value, (unsigned long)up->port.membase + offset);
145}
146
147#define serial_inp(up, offset) serial_in(up, offset)
148#define serial_outp(up, offset, value) serial_out(up, offset, value)
149
150/*
151 * This routine is called by rs_init() to initialize a specific serial
152 * port. It determines what type of UART chip this serial port is
153 * using: 8250, 16450, 16550, 16550A. The important question is
154 * whether or not this UART is a 16550A or not, since this will
155 * determine whether or not we can use its FIFO features or not.
156 */
157static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
158{
159 unsigned char save_lcr, save_mcr;
160 unsigned long flags;
161
162 if (!up->port.iobase && !up->port.mapbase && !up->port.membase)
163 return;
164
165 DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04x, 0x%08lx): ",
166 up->port.line, up->port.iobase, up->port.membase);
167
168 /*
169 * We really do need global IRQs disabled here - we're going to
170 * be frobbing the chips IRQ enable register to see if it exists.
171 */
172 spin_lock_irqsave(&up->port.lock, flags);
173// save_flags(flags); cli();
174
175 save_mcr = serial_in(up, UART_MCR);
176 save_lcr = serial_in(up, UART_LCR);
177
178 up->port.type = PORT_16550A;
179 serial_outp(up, UART_LCR, save_lcr);
180
181 up->port.fifosize = uart_config[up->port.type].dfl_xmit_fifo_size;
182
183 if (up->port.type == PORT_UNKNOWN)
184 goto out;
185
186 /*
187 * Reset the UART.
188 */
189 serial_outp(up, UART_MCR, save_mcr);
190 serial_outp(up, UART_FCR, (UART_FCR_ENABLE_FIFO |
191 UART_FCR_CLEAR_RCVR |
192 UART_FCR_CLEAR_XMIT));
193 serial_outp(up, UART_FCR, 0);
194 (void)serial_in(up, UART_RX);
195 serial_outp(up, UART_IER, 0);
196
197 out:
198 spin_unlock_irqrestore(&up->port.lock, flags);
199// restore_flags(flags);
200 DEBUG_AUTOCONF("type=%s\n", uart_config[up->port.type].name);
201}
202
203static void serial8250_stop_tx(struct uart_port *port, unsigned int tty_stop)
204{
205 struct uart_8250_port *up = (struct uart_8250_port *)port;
206
207 if (up->ier & UART_IER_THRI) {
208 up->ier &= ~UART_IER_THRI;
209 serial_out(up, UART_IER, up->ier);
210 }
211}
212
213static void serial8250_start_tx(struct uart_port *port, unsigned int tty_start)
214{
215 struct uart_8250_port *up = (struct uart_8250_port *)port;
216
217 if (!(up->ier & UART_IER_THRI)) {
218 up->ier |= UART_IER_THRI;
219 serial_out(up, UART_IER, up->ier);
220 }
221}
222
223static void serial8250_stop_rx(struct uart_port *port)
224{
225 struct uart_8250_port *up = (struct uart_8250_port *)port;
226
227 up->ier &= ~UART_IER_RLSI;
228 up->port.read_status_mask &= ~UART_LSR_DR;
229 serial_out(up, UART_IER, up->ier);
230}
231
232static void serial8250_enable_ms(struct uart_port *port)
233{
234 struct uart_8250_port *up = (struct uart_8250_port *)port;
235
236 up->ier |= UART_IER_MSI;
237 serial_out(up, UART_IER, up->ier);
238}
239
240static _INLINE_ void
241receive_chars(struct uart_8250_port *up, int *status, struct pt_regs *regs)
242{
243 struct tty_struct *tty = up->port.info->tty;
244 unsigned char ch;
245 int max_count = 256;
246
247 do {
248 if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
249 tty->flip.work.func((void *)tty);
250 if (tty->flip.count >= TTY_FLIPBUF_SIZE)
251 return; // if TTY_DONT_FLIP is set
252 }
253 ch = serial_inp(up, UART_RX);
254 *tty->flip.char_buf_ptr = ch;
255 *tty->flip.flag_buf_ptr = TTY_NORMAL;
256 up->port.icount.rx++;
257
258 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
259 UART_LSR_FE | UART_LSR_OE))) {
260 /*
261 * For statistics only
262 */
263 if (*status & UART_LSR_BI) {
264 *status &= ~(UART_LSR_FE | UART_LSR_PE);
265 up->port.icount.brk++;
266 /*
267 * We do the SysRQ and SAK checking
268 * here because otherwise the break
269 * may get masked by ignore_status_mask
270 * or read_status_mask.
271 */
272 if (uart_handle_break(&up->port))
273 goto ignore_char;
274 } else if (*status & UART_LSR_PE)
275 up->port.icount.parity++;
276 else if (*status & UART_LSR_FE)
277 up->port.icount.frame++;
278 if (*status & UART_LSR_OE)
279 up->port.icount.overrun++;
280
281 /*
282 * Mask off conditions which should be ingored.
283 */
284 *status &= up->port.read_status_mask;
285
286#ifdef CONFIG_SERIAL_AU1X00_CONSOLE
287 if (up->port.line == up->port.cons->index) {
288 /* Recover the break flag from console xmit */
289 *status |= up->lsr_break_flag;
290 up->lsr_break_flag = 0;
291 }
292#endif
293 if (*status & UART_LSR_BI) {
294 DEBUG_INTR("handling break....");
295 *tty->flip.flag_buf_ptr = TTY_BREAK;
296 } else if (*status & UART_LSR_PE)
297 *tty->flip.flag_buf_ptr = TTY_PARITY;
298 else if (*status & UART_LSR_FE)
299 *tty->flip.flag_buf_ptr = TTY_FRAME;
300 }
301 if (uart_handle_sysrq_char(&up->port, ch, regs))
302 goto ignore_char;
303 if ((*status & up->port.ignore_status_mask) == 0) {
304 tty->flip.flag_buf_ptr++;
305 tty->flip.char_buf_ptr++;
306 tty->flip.count++;
307 }
308 if ((*status & UART_LSR_OE) &&
309 tty->flip.count < TTY_FLIPBUF_SIZE) {
310 /*
311 * Overrun is special, since it's reported
312 * immediately, and doesn't affect the current
313 * character.
314 */
315 *tty->flip.flag_buf_ptr = TTY_OVERRUN;
316 tty->flip.flag_buf_ptr++;
317 tty->flip.char_buf_ptr++;
318 tty->flip.count++;
319 }
320 ignore_char:
321 *status = serial_inp(up, UART_LSR);
322 } while ((*status & UART_LSR_DR) && (max_count-- > 0));
323 spin_unlock(&up->port.lock);
324 tty_flip_buffer_push(tty);
325 spin_lock(&up->port.lock);
326}
327
328static _INLINE_ void transmit_chars(struct uart_8250_port *up)
329{
330 struct circ_buf *xmit = &up->port.info->xmit;
331 int count;
332
333 if (up->port.x_char) {
334 serial_outp(up, UART_TX, up->port.x_char);
335 up->port.icount.tx++;
336 up->port.x_char = 0;
337 return;
338 }
339 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
340 serial8250_stop_tx(&up->port, 0);
341 return;
342 }
343
344 count = up->port.fifosize;
345 do {
346 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
347 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
348 up->port.icount.tx++;
349 if (uart_circ_empty(xmit))
350 break;
351 } while (--count > 0);
352
353 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
354 uart_write_wakeup(&up->port);
355
356 DEBUG_INTR("THRE...");
357
358 if (uart_circ_empty(xmit))
359 serial8250_stop_tx(&up->port, 0);
360}
361
362static _INLINE_ void check_modem_status(struct uart_8250_port *up)
363{
364 int status;
365
366 status = serial_in(up, UART_MSR);
367
368 if ((status & UART_MSR_ANY_DELTA) == 0)
369 return;
370
371 if (status & UART_MSR_TERI)
372 up->port.icount.rng++;
373 if (status & UART_MSR_DDSR)
374 up->port.icount.dsr++;
375 if (status & UART_MSR_DDCD)
376 uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
377 if (status & UART_MSR_DCTS)
378 uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
379
380 wake_up_interruptible(&up->port.info->delta_msr_wait);
381}
382
383/*
384 * This handles the interrupt from one port.
385 */
386static inline void
387serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs)
388{
389 unsigned int status = serial_inp(up, UART_LSR);
390
391 DEBUG_INTR("status = %x...", status);
392
393 if (status & UART_LSR_DR)
394 receive_chars(up, &status, regs);
395 check_modem_status(up);
396 if (status & UART_LSR_THRE)
397 transmit_chars(up);
398}
399
400/*
401 * This is the serial driver's interrupt routine.
402 *
403 * Arjan thinks the old way was overly complex, so it got simplified.
404 * Alan disagrees, saying that need the complexity to handle the weird
405 * nature of ISA shared interrupts. (This is a special exception.)
406 *
407 * In order to handle ISA shared interrupts properly, we need to check
408 * that all ports have been serviced, and therefore the ISA interrupt
409 * line has been de-asserted.
410 *
411 * This means we need to loop through all ports. checking that they
412 * don't have an interrupt pending.
413 */
414static irqreturn_t serial8250_interrupt(int irq, void *dev_id, struct pt_regs *regs)
415{
416 struct irq_info *i = dev_id;
417 struct list_head *l, *end = NULL;
418 int pass_counter = 0;
419
420 DEBUG_INTR("serial8250_interrupt(%d)...", irq);
421
422 spin_lock(&i->lock);
423
424 l = i->head;
425 do {
426 struct uart_8250_port *up;
427 unsigned int iir;
428
429 up = list_entry(l, struct uart_8250_port, list);
430
431 iir = serial_in(up, UART_IIR);
432 if (!(iir & UART_IIR_NO_INT)) {
433 spin_lock(&up->port.lock);
434 serial8250_handle_port(up, regs);
435 spin_unlock(&up->port.lock);
436
437 end = NULL;
438 } else if (end == NULL)
439 end = l;
440
441 l = l->next;
442
443 if (l == i->head && pass_counter++ > PASS_LIMIT) {
444 /* If we hit this, we're dead. */
445 printk(KERN_ERR "serial8250: too much work for "
446 "irq%d\n", irq);
447 break;
448 }
449 } while (l != end);
450
451 spin_unlock(&i->lock);
452
453 DEBUG_INTR("end.\n");
454 /* FIXME! Was it really ours? */
455 return IRQ_HANDLED;
456}
457
458/*
459 * To support ISA shared interrupts, we need to have one interrupt
460 * handler that ensures that the IRQ line has been deasserted
461 * before returning. Failing to do this will result in the IRQ
462 * line being stuck active, and, since ISA irqs are edge triggered,
463 * no more IRQs will be seen.
464 */
465static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
466{
467 spin_lock_irq(&i->lock);
468
469 if (!list_empty(i->head)) {
470 if (i->head == &up->list)
471 i->head = i->head->next;
472 list_del(&up->list);
473 } else {
474 BUG_ON(i->head != &up->list);
475 i->head = NULL;
476 }
477
478 spin_unlock_irq(&i->lock);
479}
480
481static int serial_link_irq_chain(struct uart_8250_port *up)
482{
483 struct irq_info *i = irq_lists + up->port.irq;
484 int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? SA_SHIRQ : 0;
485
486 spin_lock_irq(&i->lock);
487
488 if (i->head) {
489 list_add(&up->list, i->head);
490 spin_unlock_irq(&i->lock);
491
492 ret = 0;
493 } else {
494 INIT_LIST_HEAD(&up->list);
495 i->head = &up->list;
496 spin_unlock_irq(&i->lock);
497
498 ret = request_irq(up->port.irq, serial8250_interrupt,
499 irq_flags, "serial", i);
500 if (ret < 0)
501 serial_do_unlink(i, up);
502 }
503
504 return ret;
505}
506
507static void serial_unlink_irq_chain(struct uart_8250_port *up)
508{
509 struct irq_info *i = irq_lists + up->port.irq;
510
511 BUG_ON(i->head == NULL);
512
513 if (list_empty(i->head))
514 free_irq(up->port.irq, i);
515
516 serial_do_unlink(i, up);
517}
518
519/*
520 * This function is used to handle ports that do not have an
521 * interrupt. This doesn't work very well for 16450's, but gives
522 * barely passable results for a 16550A. (Although at the expense
523 * of much CPU overhead).
524 */
525static void serial8250_timeout(unsigned long data)
526{
527 struct uart_8250_port *up = (struct uart_8250_port *)data;
528 unsigned int timeout;
529 unsigned int iir;
530
531 iir = serial_in(up, UART_IIR);
532 if (!(iir & UART_IIR_NO_INT)) {
533 spin_lock(&up->port.lock);
534 serial8250_handle_port(up, NULL);
535 spin_unlock(&up->port.lock);
536 }
537
538 timeout = up->port.timeout;
539 timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
540 mod_timer(&up->timer, jiffies + timeout);
541}
542
543static unsigned int serial8250_tx_empty(struct uart_port *port)
544{
545 struct uart_8250_port *up = (struct uart_8250_port *)port;
546 unsigned long flags;
547 unsigned int ret;
548
549 spin_lock_irqsave(&up->port.lock, flags);
550 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
551 spin_unlock_irqrestore(&up->port.lock, flags);
552
553 return ret;
554}
555
556static unsigned int serial8250_get_mctrl(struct uart_port *port)
557{
558 struct uart_8250_port *up = (struct uart_8250_port *)port;
559 unsigned long flags;
560 unsigned char status;
561 unsigned int ret;
562
563 spin_lock_irqsave(&up->port.lock, flags);
564 status = serial_in(up, UART_MSR);
565 spin_unlock_irqrestore(&up->port.lock, flags);
566
567 ret = 0;
568 if (status & UART_MSR_DCD)
569 ret |= TIOCM_CAR;
570 if (status & UART_MSR_RI)
571 ret |= TIOCM_RNG;
572 if (status & UART_MSR_DSR)
573 ret |= TIOCM_DSR;
574 if (status & UART_MSR_CTS)
575 ret |= TIOCM_CTS;
576 return ret;
577}
578
579static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl)
580{
581 struct uart_8250_port *up = (struct uart_8250_port *)port;
582 unsigned char mcr = 0;
583
584 if (mctrl & TIOCM_RTS)
585 mcr |= UART_MCR_RTS;
586 if (mctrl & TIOCM_DTR)
587 mcr |= UART_MCR_DTR;
588 if (mctrl & TIOCM_OUT1)
589 mcr |= UART_MCR_OUT1;
590 if (mctrl & TIOCM_OUT2)
591 mcr |= UART_MCR_OUT2;
592 if (mctrl & TIOCM_LOOP)
593 mcr |= UART_MCR_LOOP;
594
595 mcr = (mcr & up->mcr_mask) | up->mcr_force;
596
597 serial_out(up, UART_MCR, mcr);
598}
599
600static void serial8250_break_ctl(struct uart_port *port, int break_state)
601{
602 struct uart_8250_port *up = (struct uart_8250_port *)port;
603 unsigned long flags;
604
605 spin_lock_irqsave(&up->port.lock, flags);
606 if (break_state == -1)
607 up->lcr |= UART_LCR_SBC;
608 else
609 up->lcr &= ~UART_LCR_SBC;
610 serial_out(up, UART_LCR, up->lcr);
611 spin_unlock_irqrestore(&up->port.lock, flags);
612}
613
614static int serial8250_startup(struct uart_port *port)
615{
616 struct uart_8250_port *up = (struct uart_8250_port *)port;
617 unsigned long flags;
618 int retval;
619
620 /*
621 * Clear the FIFO buffers and disable them.
622 * (they will be reeanbled in set_termios())
623 */
624 if (uart_config[up->port.type].flags & UART_CLEAR_FIFO) {
625 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
626 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
627 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
628 serial_outp(up, UART_FCR, 0);
629 }
630
631 /*
632 * Clear the interrupt registers.
633 */
634 (void) serial_inp(up, UART_LSR);
635 (void) serial_inp(up, UART_RX);
636 (void) serial_inp(up, UART_IIR);
637 (void) serial_inp(up, UART_MSR);
638
639 /*
640 * At this point, there's no way the LSR could still be 0xff;
641 * if it is, then bail out, because there's likely no UART
642 * here.
643 */
644 if (!(up->port.flags & UPF_BUGGY_UART) &&
645 (serial_inp(up, UART_LSR) == 0xff)) {
646 printk("ttyS%d: LSR safety check engaged!\n", up->port.line);
647 return -ENODEV;
648 }
649
650 retval = serial_link_irq_chain(up);
651 if (retval)
652 return retval;
653
654 /*
655 * Now, initialize the UART
656 */
657 serial_outp(up, UART_LCR, UART_LCR_WLEN8);
658
659 spin_lock_irqsave(&up->port.lock, flags);
660 if (up->port.flags & UPF_FOURPORT) {
661 if (!is_real_interrupt(up->port.irq))
662 up->port.mctrl |= TIOCM_OUT1;
663 } else
664 /*
665 * Most PC uarts need OUT2 raised to enable interrupts.
666 */
667 if (is_real_interrupt(up->port.irq))
668 up->port.mctrl |= TIOCM_OUT2;
669
670 serial8250_set_mctrl(&up->port, up->port.mctrl);
671 spin_unlock_irqrestore(&up->port.lock, flags);
672
673 /*
674 * Finally, enable interrupts. Note: Modem status interrupts
675 * are set via set_termios(), which will be occurring imminently
676 * anyway, so we don't enable them here.
677 */
678 up->ier = UART_IER_RLSI | UART_IER_RDI;
679 serial_outp(up, UART_IER, up->ier);
680
681 if (up->port.flags & UPF_FOURPORT) {
682 unsigned int icp;
683 /*
684 * Enable interrupts on the AST Fourport board
685 */
686 icp = (up->port.iobase & 0xfe0) | 0x01f;
687 outb_p(0x80, icp);
688 (void) inb_p(icp);
689 }
690
691 /*
692 * And clear the interrupt registers again for luck.
693 */
694 (void) serial_inp(up, UART_LSR);
695 (void) serial_inp(up, UART_RX);
696 (void) serial_inp(up, UART_IIR);
697 (void) serial_inp(up, UART_MSR);
698
699 return 0;
700}
701
702static void serial8250_shutdown(struct uart_port *port)
703{
704 struct uart_8250_port *up = (struct uart_8250_port *)port;
705 unsigned long flags;
706
707 /*
708 * Disable interrupts from this port
709 */
710 up->ier = 0;
711 serial_outp(up, UART_IER, 0);
712
713 spin_lock_irqsave(&up->port.lock, flags);
714 if (up->port.flags & UPF_FOURPORT) {
715 /* reset interrupts on the AST Fourport board */
716 inb((up->port.iobase & 0xfe0) | 0x1f);
717 up->port.mctrl |= TIOCM_OUT1;
718 } else
719 up->port.mctrl &= ~TIOCM_OUT2;
720
721 serial8250_set_mctrl(&up->port, up->port.mctrl);
722 spin_unlock_irqrestore(&up->port.lock, flags);
723
724 /*
725 * Disable break condition and FIFOs
726 */
727 serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC);
728 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO |
729 UART_FCR_CLEAR_RCVR |
730 UART_FCR_CLEAR_XMIT);
731 serial_outp(up, UART_FCR, 0);
732
733 /*
734 * Read data port to reset things, and then unlink from
735 * the IRQ chain.
736 */
737 (void) serial_in(up, UART_RX);
738
739 if (!is_real_interrupt(up->port.irq))
740 del_timer_sync(&up->timer);
741 else
742 serial_unlink_irq_chain(up);
743}
744
745static unsigned int serial8250_get_divisor(struct uart_port *port, unsigned int baud)
746{
747 unsigned int quot;
748
749 /*
750 * Handle magic divisors for baud rates above baud_base on
751 * SMSC SuperIO chips.
752 */
753 if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
754 baud == (port->uartclk/4))
755 quot = 0x8001;
756 else if ((port->flags & UPF_MAGIC_MULTIPLIER) &&
757 baud == (port->uartclk/8))
758 quot = 0x8002;
759 else
760 quot = uart_get_divisor(port, baud);
761
762 return quot;
763}
764
765static void
766serial8250_set_termios(struct uart_port *port, struct termios *termios,
767 struct termios *old)
768{
769 struct uart_8250_port *up = (struct uart_8250_port *)port;
770 unsigned char cval, fcr = 0;
771 unsigned long flags;
772 unsigned int baud, quot;
773
774 switch (termios->c_cflag & CSIZE) {
775 case CS5:
776 cval = 0x00;
777 break;
778 case CS6:
779 cval = 0x01;
780 break;
781 case CS7:
782 cval = 0x02;
783 break;
784 default:
785 case CS8:
786 cval = 0x03;
787 break;
788 }
789
790 if (termios->c_cflag & CSTOPB)
791 cval |= 0x04;
792 if (termios->c_cflag & PARENB)
793 cval |= UART_LCR_PARITY;
794 if (!(termios->c_cflag & PARODD))
795 cval |= UART_LCR_EPAR;
796#ifdef CMSPAR
797 if (termios->c_cflag & CMSPAR)
798 cval |= UART_LCR_SPAR;
799#endif
800
801 /*
802 * Ask the core to calculate the divisor for us.
803 */
804 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
805 quot = serial8250_get_divisor(port, baud);
806 quot = 0x35; /* FIXME */
807
808 /*
809 * Work around a bug in the Oxford Semiconductor 952 rev B
810 * chip which causes it to seriously miscalculate baud rates
811 * when DLL is 0.
812 */
813 if ((quot & 0xff) == 0 && up->port.type == PORT_16C950 &&
814 up->rev == 0x5201)
815 quot ++;
816
817 if (uart_config[up->port.type].flags & UART_USE_FIFO) {
818 if (baud < 2400)
819 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_1;
820 else
821 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_8;
822 }
823
824 /*
825 * Ok, we're now changing the port state. Do it with
826 * interrupts disabled.
827 */
828 spin_lock_irqsave(&up->port.lock, flags);
829
830 /*
831 * Update the per-port timeout.
832 */
833 uart_update_timeout(port, termios->c_cflag, baud);
834
835 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
836 if (termios->c_iflag & INPCK)
837 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
838 if (termios->c_iflag & (BRKINT | PARMRK))
839 up->port.read_status_mask |= UART_LSR_BI;
840
841 /*
842 * Characteres to ignore
843 */
844 up->port.ignore_status_mask = 0;
845 if (termios->c_iflag & IGNPAR)
846 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
847 if (termios->c_iflag & IGNBRK) {
848 up->port.ignore_status_mask |= UART_LSR_BI;
849 /*
850 * If we're ignoring parity and break indicators,
851 * ignore overruns too (for real raw support).
852 */
853 if (termios->c_iflag & IGNPAR)
854 up->port.ignore_status_mask |= UART_LSR_OE;
855 }
856
857 /*
858 * ignore all characters if CREAD is not set
859 */
860 if ((termios->c_cflag & CREAD) == 0)
861 up->port.ignore_status_mask |= UART_LSR_DR;
862
863 /*
864 * CTS flow control flag and modem status interrupts
865 */
866 up->ier &= ~UART_IER_MSI;
867 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
868 up->ier |= UART_IER_MSI;
869
870 serial_out(up, UART_IER, up->ier);
871 serial_outp(up, 0x28, quot & 0xffff);
872 up->lcr = cval; /* Save LCR */
873 if (up->port.type != PORT_16750) {
874 if (fcr & UART_FCR_ENABLE_FIFO) {
875 /* emulated UARTs (Lucent Venus 167x) need two steps */
876 serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO);
877 }
878 serial_outp(up, UART_FCR, fcr); /* set fcr */
879 }
880 spin_unlock_irqrestore(&up->port.lock, flags);
881}
882
883static void
884serial8250_pm(struct uart_port *port, unsigned int state,
885 unsigned int oldstate)
886{
887 struct uart_8250_port *up = (struct uart_8250_port *)port;
888 if (state) {
889 /* sleep */
890 if (up->pm)
891 up->pm(port, state, oldstate);
892 } else {
893 /* wake */
894 if (up->pm)
895 up->pm(port, state, oldstate);
896 }
897}
898
899/*
900 * Resource handling. This is complicated by the fact that resources
901 * depend on the port type. Maybe we should be claiming the standard
902 * 8250 ports, and then trying to get other resources as necessary?
903 */
904static int
905serial8250_request_std_resource(struct uart_8250_port *up, struct resource **res)
906{
907 unsigned int size = 8 << up->port.regshift;
908 int ret = 0;
909
910 switch (up->port.iotype) {
911 case SERIAL_IO_MEM:
912 if (up->port.mapbase) {
913 *res = request_mem_region(up->port.mapbase, size, "serial");
914 if (!*res)
915 ret = -EBUSY;
916 }
917 break;
918
919 case SERIAL_IO_HUB6:
920 case SERIAL_IO_PORT:
921 *res = request_region(up->port.iobase, size, "serial");
922 if (!*res)
923 ret = -EBUSY;
924 break;
925 }
926 return ret;
927}
928
929
930static void serial8250_release_port(struct uart_port *port)
931{
932 struct uart_8250_port *up = (struct uart_8250_port *)port;
933 unsigned long start, offset = 0, size = 0;
934
935 size <<= up->port.regshift;
936
937 switch (up->port.iotype) {
938 case SERIAL_IO_MEM:
939 if (up->port.mapbase) {
940 /*
941 * Unmap the area.
942 */
943 iounmap(up->port.membase);
944 up->port.membase = NULL;
945
946 start = up->port.mapbase;
947
948 if (size)
949 release_mem_region(start + offset, size);
950 release_mem_region(start, 8 << up->port.regshift);
951 }
952 break;
953
954 case SERIAL_IO_HUB6:
955 case SERIAL_IO_PORT:
956 start = up->port.iobase;
957
958 if (size)
959 release_region(start + offset, size);
960 release_region(start + offset, 8 << up->port.regshift);
961 break;
962
963 default:
964 break;
965 }
966}
967
968static int serial8250_request_port(struct uart_port *port)
969{
970 struct uart_8250_port *up = (struct uart_8250_port *)port;
971 struct resource *res = NULL, *res_rsa = NULL;
972 int ret = 0;
973
974 ret = serial8250_request_std_resource(up, &res);
975
976 /*
977 * If we have a mapbase, then request that as well.
978 */
979 if (ret == 0 && up->port.flags & UPF_IOREMAP) {
980 int size = res->end - res->start + 1;
981
982 up->port.membase = ioremap(up->port.mapbase, size);
983 if (!up->port.membase)
984 ret = -ENOMEM;
985 }
986
987 if (ret < 0) {
988 if (res_rsa)
989 release_resource(res_rsa);
990 if (res)
991 release_resource(res);
992 }
993 return ret;
994}
995
996static void serial8250_config_port(struct uart_port *port, int flags)
997{
998 struct uart_8250_port *up = (struct uart_8250_port *)port;
999 struct resource *res_std = NULL, *res_rsa = NULL;
1000 int probeflags = PROBE_ANY;
1001
1002 probeflags &= ~PROBE_RSA;
1003
1004 if (flags & UART_CONFIG_TYPE)
1005 autoconfig(up, probeflags);
1006
1007 /*
1008 * If the port wasn't an RSA port, release the resource.
1009 */
1010 if (up->port.type != PORT_RSA && res_rsa)
1011 release_resource(res_rsa);
1012
1013 if (up->port.type == PORT_UNKNOWN && res_std)
1014 release_resource(res_std);
1015}
1016
1017static int
1018serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
1019{
1020 if (ser->irq >= NR_IRQS || ser->irq < 0 ||
1021 ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
1022 ser->type > PORT_MAX_8250 || ser->type == PORT_CIRRUS ||
1023 ser->type == PORT_STARTECH)
1024 return -EINVAL;
1025 return 0;
1026}
1027
1028static const char *
1029serial8250_type(struct uart_port *port)
1030{
1031 int type = port->type;
1032
1033 if (type >= ARRAY_SIZE(uart_config))
1034 type = 0;
1035 return uart_config[type].name;
1036}
1037
1038static struct uart_ops serial8250_pops = {
1039 .tx_empty = serial8250_tx_empty,
1040 .set_mctrl = serial8250_set_mctrl,
1041 .get_mctrl = serial8250_get_mctrl,
1042 .stop_tx = serial8250_stop_tx,
1043 .start_tx = serial8250_start_tx,
1044 .stop_rx = serial8250_stop_rx,
1045 .enable_ms = serial8250_enable_ms,
1046 .break_ctl = serial8250_break_ctl,
1047 .startup = serial8250_startup,
1048 .shutdown = serial8250_shutdown,
1049 .set_termios = serial8250_set_termios,
1050 .pm = serial8250_pm,
1051 .type = serial8250_type,
1052 .release_port = serial8250_release_port,
1053 .request_port = serial8250_request_port,
1054 .config_port = serial8250_config_port,
1055 .verify_port = serial8250_verify_port,
1056};
1057
1058static struct uart_8250_port serial8250_ports[UART_NR];
1059
1060static void __init serial8250_isa_init_ports(void)
1061{
1062 struct uart_8250_port *up;
1063 static int first = 1;
1064 int i;
1065
1066 if (!first)
1067 return;
1068 first = 0;
1069
1070 for (i = 0, up = serial8250_ports; i < ARRAY_SIZE(old_serial_port);
1071 i++, up++) {
1072 up->port.iobase = old_serial_port[i].port;
1073 up->port.irq = old_serial_port[i].irq;
1074 up->port.uartclk = get_au1x00_uart_baud_base();
1075 up->port.flags = old_serial_port[i].flags;
1076 up->port.hub6 = old_serial_port[i].hub6;
1077 up->port.membase = old_serial_port[i].iomem_base;
1078 up->port.iotype = old_serial_port[i].io_type;
1079 up->port.regshift = old_serial_port[i].iomem_reg_shift;
1080 up->port.ops = &serial8250_pops;
1081 }
1082}
1083
1084static void __init serial8250_register_ports(struct uart_driver *drv)
1085{
1086 int i;
1087
1088 serial8250_isa_init_ports();
1089
1090 for (i = 0; i < UART_NR; i++) {
1091 struct uart_8250_port *up = &serial8250_ports[i];
1092
1093 up->port.line = i;
1094 up->port.ops = &serial8250_pops;
1095 init_timer(&up->timer);
1096 up->timer.function = serial8250_timeout;
1097
1098 /*
1099 * ALPHA_KLUDGE_MCR needs to be killed.
1100 */
1101 up->mcr_mask = ~ALPHA_KLUDGE_MCR;
1102 up->mcr_force = ALPHA_KLUDGE_MCR;
1103
1104 uart_add_one_port(drv, &up->port);
1105 }
1106}
1107
1108#ifdef CONFIG_SERIAL_AU1X00_CONSOLE
1109
1110#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1111
1112/*
1113 * Wait for transmitter & holding register to empty
1114 */
1115static inline void wait_for_xmitr(struct uart_8250_port *up)
1116{
1117 unsigned int status, tmout = 10000;
1118
1119 /* Wait up to 10ms for the character(s) to be sent. */
1120 do {
1121 status = serial_in(up, UART_LSR);
1122
1123 if (status & UART_LSR_BI)
1124 up->lsr_break_flag = UART_LSR_BI;
1125
1126 if (--tmout == 0)
1127 break;
1128 udelay(1);
1129 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1130
1131 /* Wait up to 1s for flow control if necessary */
1132 if (up->port.flags & UPF_CONS_FLOW) {
1133 tmout = 1000000;
1134 while (--tmout &&
1135 ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
1136 udelay(1);
1137 }
1138}
1139
1140/*
1141 * Print a string to the serial port trying not to disturb
1142 * any possible real use of the port...
1143 *
1144 * The console_lock must be held when we get here.
1145 */
1146static void
1147serial8250_console_write(struct console *co, const char *s, unsigned int count)
1148{
1149 struct uart_8250_port *up = &serial8250_ports[co->index];
1150 unsigned int ier;
1151 int i;
1152
1153 /*
1154 * First save the UER then disable the interrupts
1155 */
1156 ier = serial_in(up, UART_IER);
1157 serial_out(up, UART_IER, 0);
1158
1159 /*
1160 * Now, do each character
1161 */
1162 for (i = 0; i < count; i++, s++) {
1163 wait_for_xmitr(up);
1164
1165 /*
1166 * Send the character out.
1167 * If a LF, also do CR...
1168 */
1169 serial_out(up, UART_TX, *s);
1170 if (*s == 10) {
1171 wait_for_xmitr(up);
1172 serial_out(up, UART_TX, 13);
1173 }
1174 }
1175
1176 /*
1177 * Finally, wait for transmitter to become empty
1178 * and restore the IER
1179 */
1180 wait_for_xmitr(up);
1181 serial_out(up, UART_IER, ier);
1182}
1183
1184static int __init serial8250_console_setup(struct console *co, char *options)
1185{
1186 struct uart_port *port;
1187 int baud = 9600;
1188 int bits = 8;
1189 int parity = 'n';
1190 int flow = 'n';
1191
1192 /*
1193 * Check whether an invalid uart number has been specified, and
1194 * if so, search for the first available port that does have
1195 * console support.
1196 */
1197 if (co->index >= UART_NR)
1198 co->index = 0;
1199 port = &serial8250_ports[co->index].port;
1200
1201 /*
1202 * Temporary fix.
1203 */
1204 spin_lock_init(&port->lock);
1205
1206 if (options)
1207 uart_parse_options(options, &baud, &parity, &bits, &flow);
1208
1209 return uart_set_options(port, co, baud, parity, bits, flow);
1210}
1211
1212extern struct uart_driver serial8250_reg;
1213static struct console serial8250_console = {
1214 .name = "ttyS",
1215 .write = serial8250_console_write,
1216 .device = uart_console_device,
1217 .setup = serial8250_console_setup,
1218 .flags = CON_PRINTBUFFER,
1219 .index = -1,
1220 .data = &serial8250_reg,
1221};
1222
1223static int __init serial8250_console_init(void)
1224{
1225 serial8250_isa_init_ports();
1226 register_console(&serial8250_console);
1227 return 0;
1228}
1229console_initcall(serial8250_console_init);
1230
1231#define SERIAL8250_CONSOLE &serial8250_console
1232#else
1233#define SERIAL8250_CONSOLE NULL
1234#endif
1235
1236static struct uart_driver serial8250_reg = {
1237 .owner = THIS_MODULE,
1238 .driver_name = "serial",
1239 .devfs_name = "tts/",
1240 .dev_name = "ttyS",
1241 .major = TTY_MAJOR,
1242 .minor = 64,
1243 .nr = UART_NR,
1244 .cons = SERIAL8250_CONSOLE,
1245};
1246
1247int __init early_serial_setup(struct uart_port *port)
1248{
1249 serial8250_isa_init_ports();
1250 serial8250_ports[port->line].port = *port;
1251 serial8250_ports[port->line].port.ops = &serial8250_pops;
1252 return 0;
1253}
1254
1255/**
1256 * serial8250_suspend_port - suspend one serial port
1257 * @line: serial line number
1258 * @level: the level of port suspension, as per uart_suspend_port
1259 *
1260 * Suspend one serial port.
1261 */
1262void serial8250_suspend_port(int line)
1263{
1264 uart_suspend_port(&serial8250_reg, &serial8250_ports[line].port);
1265}
1266
1267/**
1268 * serial8250_resume_port - resume one serial port
1269 * @line: serial line number
1270 * @level: the level of port resumption, as per uart_resume_port
1271 *
1272 * Resume one serial port.
1273 */
1274void serial8250_resume_port(int line)
1275{
1276 uart_resume_port(&serial8250_reg, &serial8250_ports[line].port);
1277}
1278
1279static int __init serial8250_init(void)
1280{
1281 int ret, i;
1282
1283 printk(KERN_INFO "Serial: Au1x00 driver\n");
1284
1285 for (i = 0; i < NR_IRQS; i++)
1286 spin_lock_init(&irq_lists[i].lock);
1287
1288 ret = uart_register_driver(&serial8250_reg);
1289 if (ret >= 0)
1290 serial8250_register_ports(&serial8250_reg);
1291
1292 return ret;
1293}
1294
1295static void __exit serial8250_exit(void)
1296{
1297 int i;
1298
1299 for (i = 0; i < UART_NR; i++)
1300 uart_remove_one_port(&serial8250_reg, &serial8250_ports[i].port);
1301
1302 uart_unregister_driver(&serial8250_reg);
1303}
1304
1305module_init(serial8250_init);
1306module_exit(serial8250_exit);
1307
1308EXPORT_SYMBOL(serial8250_suspend_port);
1309EXPORT_SYMBOL(serial8250_resume_port);
1310
1311MODULE_LICENSE("GPL");
1312MODULE_DESCRIPTION("Au1x00 serial driver\n");
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-15 04:47:36 -0500