Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / drivers / serial / bfin_5xx.c
1 /*
2  * File:         drivers/serial/bfin_5xx.c
3  * Based on:     Based on drivers/serial/sa1100.c
4  * Author:       Aubrey Li <aubrey.li@analog.com>
5  *
6  * Created:
7  * Description:  Driver for blackfin 5xx serial ports
8  *
9  * Modified:
10  *               Copyright 2006 Analog Devices Inc.
11  *
12  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  *
24  * You should have received a copy of the GNU General Public License
25  * along with this program; if not, see the file COPYING, or write
26  * to the Free Software Foundation, Inc.,
27  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
28  */
29
30 #if defined(CONFIG_SERIAL_BFIN_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
31 #define SUPPORT_SYSRQ
32 #endif
33
34 #include <linux/module.h>
35 #include <linux/ioport.h>
36 #include <linux/init.h>
37 #include <linux/console.h>
38 #include <linux/sysrq.h>
39 #include <linux/platform_device.h>
40 #include <linux/tty.h>
41 #include <linux/tty_flip.h>
42 #include <linux/serial_core.h>
43
44 #ifdef CONFIG_KGDB_UART
45 #include <linux/kgdb.h>
46 #include <asm/irq_regs.h>
47 #endif
48
49 #include <asm/gpio.h>
50 #include <asm/mach/bfin_serial_5xx.h>
51
52 #ifdef CONFIG_SERIAL_BFIN_DMA
53 #include <linux/dma-mapping.h>
54 #include <asm/io.h>
55 #include <asm/irq.h>
56 #include <asm/cacheflush.h>
57 #endif
58
59 /* UART name and device definitions */
60 #define BFIN_SERIAL_NAME        "ttyBF"
61 #define BFIN_SERIAL_MAJOR       204
62 #define BFIN_SERIAL_MINOR       64
63
64 /*
65  * Setup for console. Argument comes from the menuconfig
66  */
67 #define DMA_RX_XCOUNT           512
68 #define DMA_RX_YCOUNT           (PAGE_SIZE / DMA_RX_XCOUNT)
69
70 #define DMA_RX_FLUSH_JIFFIES    5
71
72 #ifdef CONFIG_SERIAL_BFIN_DMA
73 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart);
74 #else
75 static void bfin_serial_do_work(struct work_struct *work);
76 static void bfin_serial_tx_chars(struct bfin_serial_port *uart);
77 static void local_put_char(struct bfin_serial_port *uart, char ch);
78 #endif
79
80 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart);
81
82 /*
83  * interrupts are disabled on entry
84  */
85 static void bfin_serial_stop_tx(struct uart_port *port)
86 {
87         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
88
89         while (!(UART_GET_LSR(uart) & TEMT))
90                 continue;
91
92 #ifdef CONFIG_SERIAL_BFIN_DMA
93         disable_dma(uart->tx_dma_channel);
94 #else
95 #ifdef CONFIG_BF54x
96         /* Waiting for Transmission Finished */
97         while (!(UART_GET_LSR(uart) & TFI))
98                 continue;
99         /* Clear TFI bit */
100         UART_PUT_LSR(uart, TFI);
101         UART_CLEAR_IER(uart, ETBEI);
102 #else
103         unsigned short ier;
104
105         ier = UART_GET_IER(uart);
106         ier &= ~ETBEI;
107         UART_PUT_IER(uart, ier);
108 #endif
109 #endif
110 }
111
112 /*
113  * port is locked and interrupts are disabled
114  */
115 static void bfin_serial_start_tx(struct uart_port *port)
116 {
117         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
118
119 #ifdef CONFIG_SERIAL_BFIN_DMA
120         bfin_serial_dma_tx_chars(uart);
121 #else
122 #ifdef CONFIG_BF54x
123         UART_SET_IER(uart, ETBEI);
124 #else
125         unsigned short ier;
126         ier = UART_GET_IER(uart);
127         ier |= ETBEI;
128         UART_PUT_IER(uart, ier);
129 #endif
130         bfin_serial_tx_chars(uart);
131 #endif
132 }
133
134 /*
135  * Interrupts are enabled
136  */
137 static void bfin_serial_stop_rx(struct uart_port *port)
138 {
139         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
140 #ifdef  CONFIG_KGDB_UART
141         if (uart->port.line != CONFIG_KGDB_UART_PORT) {
142 #endif
143 #ifdef CONFIG_BF54x
144         UART_CLEAR_IER(uart, ERBFI);
145 #else
146         unsigned short ier;
147
148         ier = UART_GET_IER(uart);
149         ier &= ~ERBFI;
150         UART_PUT_IER(uart, ier);
151 #endif
152 #ifdef  CONFIG_KGDB_UART
153         }
154 #endif
155 }
156
157 /*
158  * Set the modem control timer to fire immediately.
159  */
160 static void bfin_serial_enable_ms(struct uart_port *port)
161 {
162 }
163
164 #ifdef CONFIG_KGDB_UART
165 static int kgdb_entry_state;
166
167 void kgdb_put_debug_char(int chr)
168 {
169         struct bfin_serial_port *uart;
170         
171         if (CONFIG_KGDB_UART_PORT<0 || CONFIG_KGDB_UART_PORT>=NR_PORTS)
172                 uart = &bfin_serial_ports[0];
173         else
174                 uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
175         
176         while (!(UART_GET_LSR(uart) & THRE)) {
177                 SSYNC();
178         }
179
180 #ifndef CONFIG_BF54x
181         UART_PUT_LCR(uart, UART_GET_LCR(uart)&(~DLAB));
182         SSYNC();
183 #endif
184         UART_PUT_CHAR(uart, (unsigned char)chr);
185         SSYNC();
186 }
187
188 int kgdb_get_debug_char(void)
189 {
190         struct bfin_serial_port *uart;
191         unsigned char chr;
192
193         if (CONFIG_KGDB_UART_PORT<0 || CONFIG_KGDB_UART_PORT>=NR_PORTS)
194                 uart = &bfin_serial_ports[0];
195         else
196                 uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
197         
198         while(!(UART_GET_LSR(uart) & DR)) {
199                 SSYNC();
200         }
201 #ifndef CONFIG_BF54x
202         UART_PUT_LCR(uart, UART_GET_LCR(uart)&(~DLAB));
203         SSYNC();
204 #endif
205         chr = UART_GET_CHAR(uart);
206         SSYNC();
207
208         return chr;
209 }
210 #endif
211
212 #ifdef CONFIG_SERIAL_BFIN_PIO
213 static void local_put_char(struct bfin_serial_port *uart, char ch)
214 {
215         unsigned short status;
216         int flags = 0;
217
218         spin_lock_irqsave(&uart->port.lock, flags);
219
220         do {
221                 status = UART_GET_LSR(uart);
222         } while (!(status & THRE));
223
224         UART_PUT_CHAR(uart, ch);
225         SSYNC();
226
227         spin_unlock_irqrestore(&uart->port.lock, flags);
228 }
229
230 static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
231 {
232         struct tty_struct *tty = uart->port.info->tty;
233         unsigned int status, ch, flg;
234         static int in_break = 0;
235 #ifdef CONFIG_KGDB_UART
236         struct pt_regs *regs = get_irq_regs();
237 #endif
238
239         status = UART_GET_LSR(uart);
240         ch = UART_GET_CHAR(uart);
241         uart->port.icount.rx++;
242
243 #ifdef CONFIG_KGDB_UART
244         if (uart->port.line == CONFIG_KGDB_UART_PORT) {
245                 if (uart->port.cons->index == CONFIG_KGDB_UART_PORT && ch == 0x1) { /* Ctrl + A */
246                         kgdb_breakkey_pressed(regs);
247                         return;
248                 } else if (kgdb_entry_state == 0 && ch == '$') {/* connection from KGDB */
249                         kgdb_entry_state = 1;
250                 } else if (kgdb_entry_state == 1 && ch == 'q') {
251                         kgdb_entry_state = 0;
252                         kgdb_breakkey_pressed(regs);
253                         return;
254                 } else if (ch == 0x3) {/* Ctrl + C */
255                         kgdb_entry_state = 0;
256                         kgdb_breakkey_pressed(regs);
257                         return;
258                 } else {
259                         kgdb_entry_state = 0;
260                 }
261         }
262 #endif
263
264         if (ANOMALY_05000230) {
265                 /* The BF533 family of processors have a nice misbehavior where
266                  * they continuously generate characters for a "single" break.
267                  * We have to basically ignore this flood until the "next" valid
268                  * character comes across.  All other Blackfin families operate
269                  * properly though.
270                  * Note: While Anomaly 05000230 does not directly address this,
271                  *       the changes that went in for it also fixed this issue.
272                  */
273                 if (in_break) {
274                         if (ch != 0) {
275                                 in_break = 0;
276                                 ch = UART_GET_CHAR(uart);
277                                 if (bfin_revid() < 5)
278                                         return;
279                         } else
280                                 return;
281                 }
282         }
283
284         if (status & BI) {
285                 if (ANOMALY_05000230)
286                         in_break = 1;
287                 uart->port.icount.brk++;
288                 if (uart_handle_break(&uart->port))
289                         goto ignore_char;
290                 status &= ~(PE | FE);
291         }
292         if (status & PE)
293                 uart->port.icount.parity++;
294         if (status & OE)
295                 uart->port.icount.overrun++;
296         if (status & FE)
297                 uart->port.icount.frame++;
298
299         status &= uart->port.read_status_mask;
300
301         if (status & BI)
302                 flg = TTY_BREAK;
303         else if (status & PE)
304                 flg = TTY_PARITY;
305         else if (status & FE)
306                 flg = TTY_FRAME;
307         else
308                 flg = TTY_NORMAL;
309
310         if (uart_handle_sysrq_char(&uart->port, ch))
311                 goto ignore_char;
312
313         uart_insert_char(&uart->port, status, OE, ch, flg);
314
315  ignore_char:
316         tty_flip_buffer_push(tty);
317 }
318
319 static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
320 {
321         struct circ_buf *xmit = &uart->port.info->xmit;
322
323         if (uart->port.x_char) {
324                 UART_PUT_CHAR(uart, uart->port.x_char);
325                 uart->port.icount.tx++;
326                 uart->port.x_char = 0;
327                 return;
328         }
329         /*
330          * Check the modem control lines before
331          * transmitting anything.
332          */
333         bfin_serial_mctrl_check(uart);
334
335         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
336                 bfin_serial_stop_tx(&uart->port);
337                 return;
338         }
339
340         local_put_char(uart, xmit->buf[xmit->tail]);
341         xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
342         uart->port.icount.tx++;
343
344         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
345                 uart_write_wakeup(&uart->port);
346
347         if (uart_circ_empty(xmit))
348                 bfin_serial_stop_tx(&uart->port);
349 }
350
351 static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
352 {
353         struct bfin_serial_port *uart = dev_id;
354
355 #ifdef CONFIG_BF54x
356         unsigned short status;
357         spin_lock(&uart->port.lock);
358         status = UART_GET_LSR(uart);
359         while ((UART_GET_IER(uart) & ERBFI) && (status & DR)) {
360                 bfin_serial_rx_chars(uart);
361                 status = UART_GET_LSR(uart);
362         }
363         spin_unlock(&uart->port.lock);
364 #else
365         spin_lock(&uart->port.lock);
366         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_RX_READY)
367                 bfin_serial_rx_chars(uart);
368         spin_unlock(&uart->port.lock);
369 #endif
370         return IRQ_HANDLED;
371 }
372
373 static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
374 {
375         struct bfin_serial_port *uart = dev_id;
376
377 #ifdef CONFIG_BF54x
378         unsigned short status;
379         spin_lock(&uart->port.lock);
380         status = UART_GET_LSR(uart);
381         while ((UART_GET_IER(uart) & ETBEI) && (status & THRE)) {
382                 bfin_serial_tx_chars(uart);
383                 status = UART_GET_LSR(uart);
384         }
385         spin_unlock(&uart->port.lock);
386 #else
387         spin_lock(&uart->port.lock);
388         while ((UART_GET_IIR(uart) & IIR_STATUS) == IIR_TX_READY)
389                 bfin_serial_tx_chars(uart);
390         spin_unlock(&uart->port.lock);
391 #endif
392         return IRQ_HANDLED;
393 }
394
395
396 static void bfin_serial_do_work(struct work_struct *work)
397 {
398         struct bfin_serial_port *uart = container_of(work, struct bfin_serial_port, cts_workqueue);
399
400         bfin_serial_mctrl_check(uart);
401 }
402 #endif
403
404 #ifdef CONFIG_SERIAL_BFIN_DMA
405 static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
406 {
407         struct circ_buf *xmit = &uart->port.info->xmit;
408         unsigned short ier;
409         int flags = 0;
410
411         if (!uart->tx_done)
412                 return;
413
414         uart->tx_done = 0;
415
416         if (uart->port.x_char) {
417                 UART_PUT_CHAR(uart, uart->port.x_char);
418                 uart->port.icount.tx++;
419                 uart->port.x_char = 0;
420                 uart->tx_done = 1;
421                 return;
422         }
423         /*
424          * Check the modem control lines before
425          * transmitting anything.
426          */
427         bfin_serial_mctrl_check(uart);
428
429         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
430                 bfin_serial_stop_tx(&uart->port);
431                 uart->tx_done = 1;
432                 return;
433         }
434
435         spin_lock_irqsave(&uart->port.lock, flags);
436         uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
437         if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
438                 uart->tx_count = UART_XMIT_SIZE - xmit->tail;
439         blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
440                                         (unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
441         set_dma_config(uart->tx_dma_channel,
442                 set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
443                         INTR_ON_BUF,
444                         DIMENSION_LINEAR,
445                         DATA_SIZE_8));
446         set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
447         set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
448         set_dma_x_modify(uart->tx_dma_channel, 1);
449         enable_dma(uart->tx_dma_channel);
450 #ifdef CONFIG_BF54x
451         UART_SET_IER(uart, ETBEI);
452 #else
453         ier = UART_GET_IER(uart);
454         ier |= ETBEI;
455         UART_PUT_IER(uart, ier);
456 #endif
457         spin_unlock_irqrestore(&uart->port.lock, flags);
458 }
459
460 static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
461 {
462         struct tty_struct *tty = uart->port.info->tty;
463         int i, flg, status;
464
465         status = UART_GET_LSR(uart);
466         uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);;
467
468         if (status & BI) {
469                 uart->port.icount.brk++;
470                 if (uart_handle_break(&uart->port))
471                         goto dma_ignore_char;
472                 status &= ~(PE | FE);
473         }
474         if (status & PE)
475                 uart->port.icount.parity++;
476         if (status & OE)
477                 uart->port.icount.overrun++;
478         if (status & FE)
479                 uart->port.icount.frame++;
480
481         status &= uart->port.read_status_mask;
482
483         if (status & BI)
484                 flg = TTY_BREAK;
485         else if (status & PE)
486                 flg = TTY_PARITY;
487         else if (status & FE)
488                 flg = TTY_FRAME;
489         else
490                 flg = TTY_NORMAL;
491
492         for (i = uart->rx_dma_buf.head; i < uart->rx_dma_buf.tail; i++) {
493                 if (uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
494                         goto dma_ignore_char;
495                 uart_insert_char(&uart->port, status, OE, uart->rx_dma_buf.buf[i], flg);
496         }
497
498  dma_ignore_char:
499         tty_flip_buffer_push(tty);
500 }
501
502 void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
503 {
504         int x_pos, pos;
505         int flags = 0;
506
507         bfin_serial_dma_tx_chars(uart);
508
509         spin_lock_irqsave(&uart->port.lock, flags);
510         x_pos = DMA_RX_XCOUNT - get_dma_curr_xcount(uart->rx_dma_channel);
511         if (x_pos == DMA_RX_XCOUNT)
512                 x_pos = 0;
513
514         pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
515
516         if (pos>uart->rx_dma_buf.tail) {
517                 uart->rx_dma_buf.tail = pos;
518                 bfin_serial_dma_rx_chars(uart);
519                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail;
520         }
521         spin_unlock_irqrestore(&uart->port.lock, flags);
522         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
523         add_timer(&(uart->rx_dma_timer));
524 }
525
526 static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
527 {
528         struct bfin_serial_port *uart = dev_id;
529         struct circ_buf *xmit = &uart->port.info->xmit;
530         unsigned short ier;
531
532         spin_lock(&uart->port.lock);
533         if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) {
534                 clear_dma_irqstat(uart->tx_dma_channel);
535                 disable_dma(uart->tx_dma_channel);
536 #ifdef CONFIG_BF54x
537                 UART_CLEAR_IER(uart, ETBEI);
538 #else
539                 ier = UART_GET_IER(uart);
540                 ier &= ~ETBEI;
541                 UART_PUT_IER(uart, ier);
542 #endif
543                 xmit->tail = (xmit->tail+uart->tx_count) &(UART_XMIT_SIZE -1);
544                 uart->port.icount.tx+=uart->tx_count;
545
546                 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
547                         uart_write_wakeup(&uart->port);
548
549                 if (uart_circ_empty(xmit))
550                         bfin_serial_stop_tx(&uart->port);
551                 uart->tx_done = 1;
552         }
553
554         spin_unlock(&uart->port.lock);
555         return IRQ_HANDLED;
556 }
557
558 static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
559 {
560         struct bfin_serial_port *uart = dev_id;
561         unsigned short irqstat;
562
563         uart->rx_dma_nrows++;
564         if (uart->rx_dma_nrows == DMA_RX_YCOUNT) {
565                 uart->rx_dma_nrows = 0;
566                 uart->rx_dma_buf.tail = DMA_RX_XCOUNT*DMA_RX_YCOUNT;
567                 bfin_serial_dma_rx_chars(uart);
568                 uart->rx_dma_buf.head = uart->rx_dma_buf.tail = 0;
569         }
570         spin_lock(&uart->port.lock);
571         irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
572         clear_dma_irqstat(uart->rx_dma_channel);
573
574         spin_unlock(&uart->port.lock);
575         return IRQ_HANDLED;
576 }
577 #endif
578
579 /*
580  * Return TIOCSER_TEMT when transmitter is not busy.
581  */
582 static unsigned int bfin_serial_tx_empty(struct uart_port *port)
583 {
584         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
585         unsigned short lsr;
586
587         lsr = UART_GET_LSR(uart);
588         if (lsr & TEMT)
589                 return TIOCSER_TEMT;
590         else
591                 return 0;
592 }
593
594 static unsigned int bfin_serial_get_mctrl(struct uart_port *port)
595 {
596 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
597         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
598         if (uart->cts_pin < 0)
599                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
600
601         if (gpio_get_value(uart->cts_pin))
602                 return TIOCM_DSR | TIOCM_CAR;
603         else
604 #endif
605                 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
606 }
607
608 static void bfin_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
609 {
610 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
611         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
612         if (uart->rts_pin < 0)
613                 return;
614
615         if (mctrl & TIOCM_RTS)
616                 gpio_set_value(uart->rts_pin, 0);
617         else
618                 gpio_set_value(uart->rts_pin, 1);
619 #endif
620 }
621
622 /*
623  * Handle any change of modem status signal since we were last called.
624  */
625 static void bfin_serial_mctrl_check(struct bfin_serial_port *uart)
626 {
627 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
628         unsigned int status;
629 # ifdef CONFIG_SERIAL_BFIN_DMA
630         struct uart_info *info = uart->port.info;
631         struct tty_struct *tty = info->tty;
632
633         status = bfin_serial_get_mctrl(&uart->port);
634         if (!(status & TIOCM_CTS)) {
635                 tty->hw_stopped = 1;
636         } else {
637                 tty->hw_stopped = 0;
638         }
639 # else
640         status = bfin_serial_get_mctrl(&uart->port);
641         uart_handle_cts_change(&uart->port, status & TIOCM_CTS);
642         if (!(status & TIOCM_CTS))
643                 schedule_work(&uart->cts_workqueue);
644 # endif
645 #endif
646 }
647
648 /*
649  * Interrupts are always disabled.
650  */
651 static void bfin_serial_break_ctl(struct uart_port *port, int break_state)
652 {
653         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
654         u16 lcr = UART_GET_LCR(uart);
655         if (break_state)
656                 lcr |= SB;
657         else
658                 lcr &= ~SB;
659         UART_PUT_LCR(uart, lcr);
660         SSYNC();
661 }
662
663 static int bfin_serial_startup(struct uart_port *port)
664 {
665         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
666
667 #ifdef CONFIG_SERIAL_BFIN_DMA
668         dma_addr_t dma_handle;
669
670         if (request_dma(uart->rx_dma_channel, "BFIN_UART_RX") < 0) {
671                 printk(KERN_NOTICE "Unable to attach Blackfin UART RX DMA channel\n");
672                 return -EBUSY;
673         }
674
675         if (request_dma(uart->tx_dma_channel, "BFIN_UART_TX") < 0) {
676                 printk(KERN_NOTICE "Unable to attach Blackfin UART TX DMA channel\n");
677                 free_dma(uart->rx_dma_channel);
678                 return -EBUSY;
679         }
680
681         set_dma_callback(uart->rx_dma_channel, bfin_serial_dma_rx_int, uart);
682         set_dma_callback(uart->tx_dma_channel, bfin_serial_dma_tx_int, uart);
683
684         uart->rx_dma_buf.buf = (unsigned char *)dma_alloc_coherent(NULL, PAGE_SIZE, &dma_handle, GFP_DMA);
685         uart->rx_dma_buf.head = 0;
686         uart->rx_dma_buf.tail = 0;
687         uart->rx_dma_nrows = 0;
688
689         set_dma_config(uart->rx_dma_channel,
690                 set_bfin_dma_config(DIR_WRITE, DMA_FLOW_AUTO,
691                                 INTR_ON_ROW, DIMENSION_2D,
692                                 DATA_SIZE_8));
693         set_dma_x_count(uart->rx_dma_channel, DMA_RX_XCOUNT);
694         set_dma_x_modify(uart->rx_dma_channel, 1);
695         set_dma_y_count(uart->rx_dma_channel, DMA_RX_YCOUNT);
696         set_dma_y_modify(uart->rx_dma_channel, 1);
697         set_dma_start_addr(uart->rx_dma_channel, (unsigned long)uart->rx_dma_buf.buf);
698         enable_dma(uart->rx_dma_channel);
699
700         uart->rx_dma_timer.data = (unsigned long)(uart);
701         uart->rx_dma_timer.function = (void *)bfin_serial_rx_dma_timeout;
702         uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
703         add_timer(&(uart->rx_dma_timer));
704 #else
705         if (request_irq(uart->port.irq, bfin_serial_rx_int, IRQF_DISABLED,
706              "BFIN_UART_RX", uart)) {
707 # ifdef CONFIG_KGDB_UART
708                 if (uart->port.line != CONFIG_KGDB_UART_PORT) {
709 # endif
710                 printk(KERN_NOTICE "Unable to attach BlackFin UART RX interrupt\n");
711                 return -EBUSY;
712 # ifdef CONFIG_KGDB_UART
713                 }
714 # endif
715         }
716
717
718         if (request_irq
719             (uart->port.irq+1, bfin_serial_tx_int, IRQF_DISABLED,
720              "BFIN_UART_TX", uart)) {
721                 printk(KERN_NOTICE "Unable to attach BlackFin UART TX interrupt\n");
722                 free_irq(uart->port.irq, uart);
723                 return -EBUSY;
724         }
725 #endif
726 #ifdef CONFIG_BF54x
727         UART_SET_IER(uart, ERBFI);
728 #else
729         UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
730 #endif
731         return 0;
732 }
733
734 static void bfin_serial_shutdown(struct uart_port *port)
735 {
736         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
737
738 #ifdef CONFIG_SERIAL_BFIN_DMA
739         disable_dma(uart->tx_dma_channel);
740         free_dma(uart->tx_dma_channel);
741         disable_dma(uart->rx_dma_channel);
742         free_dma(uart->rx_dma_channel);
743         del_timer(&(uart->rx_dma_timer));
744 #else
745 #ifdef  CONFIG_KGDB_UART
746         if (uart->port.line != CONFIG_KGDB_UART_PORT)
747 #endif
748         free_irq(uart->port.irq, uart);
749         free_irq(uart->port.irq+1, uart);
750 #endif
751 }
752
753 static void
754 bfin_serial_set_termios(struct uart_port *port, struct ktermios *termios,
755                    struct ktermios *old)
756 {
757         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
758         unsigned long flags;
759         unsigned int baud, quot;
760         unsigned short val, ier, lsr, lcr = 0;
761
762         switch (termios->c_cflag & CSIZE) {
763         case CS8:
764                 lcr = WLS(8);
765                 break;
766         case CS7:
767                 lcr = WLS(7);
768                 break;
769         case CS6:
770                 lcr = WLS(6);
771                 break;
772         case CS5:
773                 lcr = WLS(5);
774                 break;
775         default:
776                 printk(KERN_ERR "%s: word lengh not supported\n",
777                         __FUNCTION__);
778         }
779
780         if (termios->c_cflag & CSTOPB)
781                 lcr |= STB;
782         if (termios->c_cflag & PARENB)
783                 lcr |= PEN;
784         if (!(termios->c_cflag & PARODD))
785                 lcr |= EPS;
786         if (termios->c_cflag & CMSPAR)
787                 lcr |= STP;
788
789         port->read_status_mask = OE;
790         if (termios->c_iflag & INPCK)
791                 port->read_status_mask |= (FE | PE);
792         if (termios->c_iflag & (BRKINT | PARMRK))
793                 port->read_status_mask |= BI;
794
795         /*
796          * Characters to ignore
797          */
798         port->ignore_status_mask = 0;
799         if (termios->c_iflag & IGNPAR)
800                 port->ignore_status_mask |= FE | PE;
801         if (termios->c_iflag & IGNBRK) {
802                 port->ignore_status_mask |= BI;
803                 /*
804                  * If we're ignoring parity and break indicators,
805                  * ignore overruns too (for real raw support).
806                  */
807                 if (termios->c_iflag & IGNPAR)
808                         port->ignore_status_mask |= OE;
809         }
810
811         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
812         quot = uart_get_divisor(port, baud);
813         spin_lock_irqsave(&uart->port.lock, flags);
814
815         do {
816                 lsr = UART_GET_LSR(uart);
817         } while (!(lsr & TEMT));
818
819         /* Disable UART */
820         ier = UART_GET_IER(uart);
821 #ifdef CONFIG_BF54x
822         UART_CLEAR_IER(uart, 0xF);
823 #else
824         UART_PUT_IER(uart, 0);
825 #endif
826
827 #ifndef CONFIG_BF54x
828         /* Set DLAB in LCR to Access DLL and DLH */
829         val = UART_GET_LCR(uart);
830         val |= DLAB;
831         UART_PUT_LCR(uart, val);
832         SSYNC();
833 #endif
834
835         UART_PUT_DLL(uart, quot & 0xFF);
836         SSYNC();
837         UART_PUT_DLH(uart, (quot >> 8) & 0xFF);
838         SSYNC();
839
840 #ifndef CONFIG_BF54x
841         /* Clear DLAB in LCR to Access THR RBR IER */
842         val = UART_GET_LCR(uart);
843         val &= ~DLAB;
844         UART_PUT_LCR(uart, val);
845         SSYNC();
846 #endif
847
848         UART_PUT_LCR(uart, lcr);
849
850         /* Enable UART */
851 #ifdef CONFIG_BF54x
852         UART_SET_IER(uart, ier);
853 #else
854         UART_PUT_IER(uart, ier);
855 #endif
856
857         val = UART_GET_GCTL(uart);
858         val |= UCEN;
859         UART_PUT_GCTL(uart, val);
860
861         spin_unlock_irqrestore(&uart->port.lock, flags);
862 }
863
864 static const char *bfin_serial_type(struct uart_port *port)
865 {
866         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
867
868         return uart->port.type == PORT_BFIN ? "BFIN-UART" : NULL;
869 }
870
871 /*
872  * Release the memory region(s) being used by 'port'.
873  */
874 static void bfin_serial_release_port(struct uart_port *port)
875 {
876 }
877
878 /*
879  * Request the memory region(s) being used by 'port'.
880  */
881 static int bfin_serial_request_port(struct uart_port *port)
882 {
883         return 0;
884 }
885
886 /*
887  * Configure/autoconfigure the port.
888  */
889 static void bfin_serial_config_port(struct uart_port *port, int flags)
890 {
891         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
892
893         if (flags & UART_CONFIG_TYPE &&
894             bfin_serial_request_port(&uart->port) == 0)
895                 uart->port.type = PORT_BFIN;
896 }
897
898 /*
899  * Verify the new serial_struct (for TIOCSSERIAL).
900  * The only change we allow are to the flags and type, and
901  * even then only between PORT_BFIN and PORT_UNKNOWN
902  */
903 static int
904 bfin_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
905 {
906         return 0;
907 }
908
909 static struct uart_ops bfin_serial_pops = {
910         .tx_empty       = bfin_serial_tx_empty,
911         .set_mctrl      = bfin_serial_set_mctrl,
912         .get_mctrl      = bfin_serial_get_mctrl,
913         .stop_tx        = bfin_serial_stop_tx,
914         .start_tx       = bfin_serial_start_tx,
915         .stop_rx        = bfin_serial_stop_rx,
916         .enable_ms      = bfin_serial_enable_ms,
917         .break_ctl      = bfin_serial_break_ctl,
918         .startup        = bfin_serial_startup,
919         .shutdown       = bfin_serial_shutdown,
920         .set_termios    = bfin_serial_set_termios,
921         .type           = bfin_serial_type,
922         .release_port   = bfin_serial_release_port,
923         .request_port   = bfin_serial_request_port,
924         .config_port    = bfin_serial_config_port,
925         .verify_port    = bfin_serial_verify_port,
926 };
927
928 static void __init bfin_serial_init_ports(void)
929 {
930         static int first = 1;
931         int i;
932
933         if (!first)
934                 return;
935         first = 0;
936
937         for (i = 0; i < nr_ports; i++) {
938                 bfin_serial_ports[i].port.uartclk   = get_sclk();
939                 bfin_serial_ports[i].port.ops       = &bfin_serial_pops;
940                 bfin_serial_ports[i].port.line      = i;
941                 bfin_serial_ports[i].port.iotype    = UPIO_MEM;
942                 bfin_serial_ports[i].port.membase   =
943                         (void __iomem *)bfin_serial_resource[i].uart_base_addr;
944                 bfin_serial_ports[i].port.mapbase   =
945                         bfin_serial_resource[i].uart_base_addr;
946                 bfin_serial_ports[i].port.irq       =
947                         bfin_serial_resource[i].uart_irq;
948                 bfin_serial_ports[i].port.flags     = UPF_BOOT_AUTOCONF;
949 #ifdef CONFIG_SERIAL_BFIN_DMA
950                 bfin_serial_ports[i].tx_done        = 1;
951                 bfin_serial_ports[i].tx_count       = 0;
952                 bfin_serial_ports[i].tx_dma_channel =
953                         bfin_serial_resource[i].uart_tx_dma_channel;
954                 bfin_serial_ports[i].rx_dma_channel =
955                         bfin_serial_resource[i].uart_rx_dma_channel;
956                 init_timer(&(bfin_serial_ports[i].rx_dma_timer));
957 #else
958                 INIT_WORK(&bfin_serial_ports[i].cts_workqueue, bfin_serial_do_work);
959 #endif
960 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
961                 bfin_serial_ports[i].cts_pin        =
962                         bfin_serial_resource[i].uart_cts_pin;
963                 bfin_serial_ports[i].rts_pin        =
964                         bfin_serial_resource[i].uart_rts_pin;
965 #endif
966                 bfin_serial_hw_init(&bfin_serial_ports[i]);
967         }
968
969 }
970
971 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
972 /*
973  * If the port was already initialised (eg, by a boot loader),
974  * try to determine the current setup.
975  */
976 static void __init
977 bfin_serial_console_get_options(struct bfin_serial_port *uart, int *baud,
978                            int *parity, int *bits)
979 {
980         unsigned short status;
981
982         status = UART_GET_IER(uart) & (ERBFI | ETBEI);
983         if (status == (ERBFI | ETBEI)) {
984                 /* ok, the port was enabled */
985                 unsigned short lcr, val;
986                 unsigned short dlh, dll;
987
988                 lcr = UART_GET_LCR(uart);
989
990                 *parity = 'n';
991                 if (lcr & PEN) {
992                         if (lcr & EPS)
993                                 *parity = 'e';
994                         else
995                                 *parity = 'o';
996                 }
997                 switch (lcr & 0x03) {
998                         case 0: *bits = 5; break;
999                         case 1: *bits = 6; break;
1000                         case 2: *bits = 7; break;
1001                         case 3: *bits = 8; break;
1002                 }
1003 #ifndef CONFIG_BF54x
1004                 /* Set DLAB in LCR to Access DLL and DLH */
1005                 val = UART_GET_LCR(uart);
1006                 val |= DLAB;
1007                 UART_PUT_LCR(uart, val);
1008 #endif
1009
1010                 dll = UART_GET_DLL(uart);
1011                 dlh = UART_GET_DLH(uart);
1012
1013 #ifndef CONFIG_BF54x
1014                 /* Clear DLAB in LCR to Access THR RBR IER */
1015                 val = UART_GET_LCR(uart);
1016                 val &= ~DLAB;
1017                 UART_PUT_LCR(uart, val);
1018 #endif
1019
1020                 *baud = get_sclk() / (16*(dll | dlh << 8));
1021         }
1022         pr_debug("%s:baud = %d, parity = %c, bits= %d\n", __FUNCTION__, *baud, *parity, *bits);
1023 }
1024 #endif
1025
1026 #if defined(CONFIG_SERIAL_BFIN_CONSOLE) || defined(CONFIG_EARLY_PRINTK)
1027 static struct uart_driver bfin_serial_reg;
1028
1029 static int __init
1030 bfin_serial_console_setup(struct console *co, char *options)
1031 {
1032         struct bfin_serial_port *uart;
1033 # ifdef CONFIG_SERIAL_BFIN_CONSOLE
1034         int baud = 57600;
1035         int bits = 8;
1036         int parity = 'n';
1037 #  ifdef CONFIG_SERIAL_BFIN_CTSRTS
1038         int flow = 'r';
1039 #  else
1040         int flow = 'n';
1041 #  endif
1042 # endif
1043
1044         /*
1045          * Check whether an invalid uart number has been specified, and
1046          * if so, search for the first available port that does have
1047          * console support.
1048          */
1049         if (co->index == -1 || co->index >= nr_ports)
1050                 co->index = 0;
1051         uart = &bfin_serial_ports[co->index];
1052
1053 # ifdef CONFIG_SERIAL_BFIN_CONSOLE
1054         if (options)
1055                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1056         else
1057                 bfin_serial_console_get_options(uart, &baud, &parity, &bits);
1058
1059         return uart_set_options(&uart->port, co, baud, parity, bits, flow);
1060 # else
1061         return 0;
1062 # endif
1063 }
1064 #endif /* defined (CONFIG_SERIAL_BFIN_CONSOLE) ||
1065                                  defined (CONFIG_EARLY_PRINTK) */
1066
1067 #ifdef CONFIG_SERIAL_BFIN_CONSOLE
1068 static void bfin_serial_console_putchar(struct uart_port *port, int ch)
1069 {
1070         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
1071         while (!(UART_GET_LSR(uart) & THRE))
1072                 barrier();
1073         UART_PUT_CHAR(uart, ch);
1074         SSYNC();
1075 }
1076
1077 /*
1078  * Interrupts are disabled on entering
1079  */
1080 static void
1081 bfin_serial_console_write(struct console *co, const char *s, unsigned int count)
1082 {
1083         struct bfin_serial_port *uart = &bfin_serial_ports[co->index];
1084         int flags = 0;
1085
1086         spin_lock_irqsave(&uart->port.lock, flags);
1087         uart_console_write(&uart->port, s, count, bfin_serial_console_putchar);
1088         spin_unlock_irqrestore(&uart->port.lock, flags);
1089
1090 }
1091
1092 static struct console bfin_serial_console = {
1093         .name           = BFIN_SERIAL_NAME,
1094         .write          = bfin_serial_console_write,
1095         .device         = uart_console_device,
1096         .setup          = bfin_serial_console_setup,
1097         .flags          = CON_PRINTBUFFER,
1098         .index          = -1,
1099         .data           = &bfin_serial_reg,
1100 };
1101
1102 static int __init bfin_serial_rs_console_init(void)
1103 {
1104         bfin_serial_init_ports();
1105         register_console(&bfin_serial_console);
1106 #ifdef CONFIG_KGDB_UART
1107         kgdb_entry_state = 0;
1108         init_kgdb_uart();
1109 #endif
1110         return 0;
1111 }
1112 console_initcall(bfin_serial_rs_console_init);
1113
1114 #define BFIN_SERIAL_CONSOLE     &bfin_serial_console
1115 #else
1116 #define BFIN_SERIAL_CONSOLE     NULL
1117 #endif /* CONFIG_SERIAL_BFIN_CONSOLE */
1118
1119
1120 #ifdef CONFIG_EARLY_PRINTK
1121 static __init void early_serial_putc(struct uart_port *port, int ch)
1122 {
1123         unsigned timeout = 0xffff;
1124         struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
1125
1126         while ((!(UART_GET_LSR(uart) & THRE)) && --timeout)
1127                 cpu_relax();
1128         UART_PUT_CHAR(uart, ch);
1129 }
1130
1131 static __init void early_serial_write(struct console *con, const char *s,
1132                                         unsigned int n)
1133 {
1134         struct bfin_serial_port *uart = &bfin_serial_ports[con->index];
1135         unsigned int i;
1136
1137         for (i = 0; i < n; i++, s++) {
1138                 if (*s == '\n')
1139                         early_serial_putc(&uart->port, '\r');
1140                 early_serial_putc(&uart->port, *s);
1141         }
1142 }
1143
1144 static struct __init console bfin_early_serial_console = {
1145         .name = "early_BFuart",
1146         .write = early_serial_write,
1147         .device = uart_console_device,
1148         .flags = CON_PRINTBUFFER,
1149         .setup = bfin_serial_console_setup,
1150         .index = -1,
1151         .data  = &bfin_serial_reg,
1152 };
1153
1154 struct console __init *bfin_earlyserial_init(unsigned int port,
1155                                                 unsigned int cflag)
1156 {
1157         struct bfin_serial_port *uart;
1158         struct ktermios t;
1159
1160         if (port == -1 || port >= nr_ports)
1161                 port = 0;
1162         bfin_serial_init_ports();
1163         bfin_early_serial_console.index = port;
1164         uart = &bfin_serial_ports[port];
1165         t.c_cflag = cflag;
1166         t.c_iflag = 0;
1167         t.c_oflag = 0;
1168         t.c_lflag = ICANON;
1169         t.c_line = port;
1170         bfin_serial_set_termios(&uart->port, &t, &t);
1171         return &bfin_early_serial_console;
1172 }
1173
1174 #endif /* CONFIG_SERIAL_BFIN_CONSOLE */
1175
1176 static struct uart_driver bfin_serial_reg = {
1177         .owner                  = THIS_MODULE,
1178         .driver_name            = "bfin-uart",
1179         .dev_name               = BFIN_SERIAL_NAME,
1180         .major                  = BFIN_SERIAL_MAJOR,
1181         .minor                  = BFIN_SERIAL_MINOR,
1182         .nr                     = NR_PORTS,
1183         .cons                   = BFIN_SERIAL_CONSOLE,
1184 };
1185
1186 static int bfin_serial_suspend(struct platform_device *dev, pm_message_t state)
1187 {
1188         struct bfin_serial_port *uart = platform_get_drvdata(dev);
1189
1190         if (uart)
1191                 uart_suspend_port(&bfin_serial_reg, &uart->port);
1192
1193         return 0;
1194 }
1195
1196 static int bfin_serial_resume(struct platform_device *dev)
1197 {
1198         struct bfin_serial_port *uart = platform_get_drvdata(dev);
1199
1200         if (uart)
1201                 uart_resume_port(&bfin_serial_reg, &uart->port);
1202
1203         return 0;
1204 }
1205
1206 static int bfin_serial_probe(struct platform_device *dev)
1207 {
1208         struct resource *res = dev->resource;
1209         int i;
1210
1211         for (i = 0; i < dev->num_resources; i++, res++)
1212                 if (res->flags & IORESOURCE_MEM)
1213                         break;
1214
1215         if (i < dev->num_resources) {
1216                 for (i = 0; i < nr_ports; i++, res++) {
1217                         if (bfin_serial_ports[i].port.mapbase != res->start)
1218                                 continue;
1219                         bfin_serial_ports[i].port.dev = &dev->dev;
1220                         uart_add_one_port(&bfin_serial_reg, &bfin_serial_ports[i].port);
1221                         platform_set_drvdata(dev, &bfin_serial_ports[i]);
1222                 }
1223         }
1224
1225         return 0;
1226 }
1227
1228 static int bfin_serial_remove(struct platform_device *pdev)
1229 {
1230         struct bfin_serial_port *uart = platform_get_drvdata(pdev);
1231
1232
1233 #ifdef CONFIG_SERIAL_BFIN_CTSRTS
1234         gpio_free(uart->cts_pin);
1235         gpio_free(uart->rts_pin);
1236 #endif
1237
1238         platform_set_drvdata(pdev, NULL);
1239
1240         if (uart)
1241                 uart_remove_one_port(&bfin_serial_reg, &uart->port);
1242
1243         return 0;
1244 }
1245
1246 static struct platform_driver bfin_serial_driver = {
1247         .probe          = bfin_serial_probe,
1248         .remove         = bfin_serial_remove,
1249         .suspend        = bfin_serial_suspend,
1250         .resume         = bfin_serial_resume,
1251         .driver         = {
1252                 .name   = "bfin-uart",
1253         },
1254 };
1255
1256 static int __init bfin_serial_init(void)
1257 {
1258         int ret;
1259 #ifdef CONFIG_KGDB_UART
1260         struct bfin_serial_port *uart = &bfin_serial_ports[CONFIG_KGDB_UART_PORT];
1261         struct ktermios t;
1262 #endif
1263
1264         pr_info("Serial: Blackfin serial driver\n");
1265
1266         bfin_serial_init_ports();
1267
1268         ret = uart_register_driver(&bfin_serial_reg);
1269         if (ret == 0) {
1270                 ret = platform_driver_register(&bfin_serial_driver);
1271                 if (ret) {
1272                         pr_debug("uart register failed\n");
1273                         uart_unregister_driver(&bfin_serial_reg);
1274                 }
1275         }
1276 #ifdef CONFIG_KGDB_UART
1277         if (uart->port.cons->index != CONFIG_KGDB_UART_PORT) {
1278                 request_irq(uart->port.irq, bfin_serial_rx_int,
1279                         IRQF_DISABLED, "BFIN_UART_RX", uart);
1280                 pr_info("Request irq for kgdb uart port\n");
1281 #ifdef CONFIG_BF54x
1282                 UART_SET_IER(uart, ERBFI);
1283 #else
1284                 UART_PUT_IER(uart, UART_GET_IER(uart) | ERBFI);
1285 #endif
1286                 SSYNC();
1287                 t.c_cflag = CS8|B57600;
1288                 t.c_iflag = 0;
1289                 t.c_oflag = 0;
1290                 t.c_lflag = ICANON;
1291                 t.c_line = CONFIG_KGDB_UART_PORT;
1292                 bfin_serial_set_termios(&uart->port, &t, &t);
1293         }
1294 #endif
1295         return ret;
1296 }
1297
1298 static void __exit bfin_serial_exit(void)
1299 {
1300         platform_driver_unregister(&bfin_serial_driver);
1301         uart_unregister_driver(&bfin_serial_reg);
1302 }
1303
1304 module_init(bfin_serial_init);
1305 module_exit(bfin_serial_exit);
1306
1307 MODULE_AUTHOR("Aubrey.Li <aubrey.li@analog.com>");
1308 MODULE_DESCRIPTION("Blackfin generic serial port driver");
1309 MODULE_LICENSE("GPL");
1310 MODULE_ALIAS_CHARDEV_MAJOR(BFIN_SERIAL_MAJOR);