summaryrefslogtreecommitdiffstats
path: root/drivers/tty/serial/rp2.c
blob: 2108bf34ff90279d332c459a3c157c7334f47f20 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for Comtrol RocketPort EXPRESS/INFINITY cards
 *
 * Copyright (C) 2012 Kevin Cernekee <cernekee@gmail.com>
 *
 * Inspired by, and loosely based on:
 *
 *   ar933x_uart.c
 *     Copyright (C) 2011 Gabor Juhos <juhosg@openwrt.org>
 *
 *   rocketport_infinity_express-linux-1.20.tar.gz
 *     Copyright (C) 2004-2011 Comtrol, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 */

#include <linux/bitops.h>
#include <linux/compiler.h>
#include <linux/completion.h>
#include <linux/console.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/slab.h>
#include <linux/sysrq.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/types.h>

#define DRV_NAME			"rp2"

#define RP2_FW_NAME			"rp2.fw"
#define RP2_UCODE_BYTES			0x3f

#define PORTS_PER_ASIC			16
#define ALL_PORTS_MASK			(BIT(PORTS_PER_ASIC) - 1)

#define UART_CLOCK			44236800
#define DEFAULT_BAUD_DIV		(UART_CLOCK / (9600 * 16))
#define FIFO_SIZE			512

/* BAR0 registers */
#define RP2_FPGA_CTL0			0x110
#define RP2_FPGA_CTL1			0x11c
#define RP2_IRQ_MASK			0x1ec
#define RP2_IRQ_MASK_EN_m		BIT(0)
#define RP2_IRQ_STATUS			0x1f0

/* BAR1 registers */
#define RP2_ASIC_SPACING		0x1000
#define RP2_ASIC_OFFSET(i)		((i) << ilog2(RP2_ASIC_SPACING))

#define RP2_PORT_BASE			0x000
#define RP2_PORT_SPACING		0x040

#define RP2_UCODE_BASE			0x400
#define RP2_UCODE_SPACING		0x80

#define RP2_CLK_PRESCALER		0xc00
#define RP2_CH_IRQ_STAT			0xc04
#define RP2_CH_IRQ_MASK			0xc08
#define RP2_ASIC_IRQ			0xd00
#define RP2_ASIC_IRQ_EN_m		BIT(20)
#define RP2_GLOBAL_CMD			0xd0c
#define RP2_ASIC_CFG			0xd04

/* port registers */
#define RP2_DATA_DWORD			0x000

#define RP2_DATA_BYTE			0x008
#define RP2_DATA_BYTE_ERR_PARITY_m	BIT(8)
#define RP2_DATA_BYTE_ERR_OVERRUN_m	BIT(9)
#define RP2_DATA_BYTE_ERR_FRAMING_m	BIT(10)
#define RP2_DATA_BYTE_BREAK_m		BIT(11)

/* This lets uart_insert_char() drop bytes received on a !CREAD port */
#define RP2_DUMMY_READ			BIT(16)

#define RP2_DATA_BYTE_EXCEPTION_MASK	(RP2_DATA_BYTE_ERR_PARITY_m | \
					 RP2_DATA_BYTE_ERR_OVERRUN_m | \
					 RP2_DATA_BYTE_ERR_FRAMING_m | \
					 RP2_DATA_BYTE_BREAK_m)

#define RP2_RX_FIFO_COUNT		0x00c
#define RP2_TX_FIFO_COUNT		0x00e

#define RP2_CHAN_STAT			0x010
#define RP2_CHAN_STAT_RXDATA_m		BIT(0)
#define RP2_CHAN_STAT_DCD_m		BIT(3)
#define RP2_CHAN_STAT_DSR_m		BIT(4)
#define RP2_CHAN_STAT_CTS_m		BIT(5)
#define RP2_CHAN_STAT_RI_m		BIT(6)
#define RP2_CHAN_STAT_OVERRUN_m		BIT(13)
#define RP2_CHAN_STAT_DSR_CHANGED_m	BIT(16)
#define RP2_CHAN_STAT_CTS_CHANGED_m	BIT(17)
#define RP2_CHAN_STAT_CD_CHANGED_m	BIT(18)
#define RP2_CHAN_STAT_RI_CHANGED_m	BIT(22)
#define RP2_CHAN_STAT_TXEMPTY_m		BIT(25)

#define RP2_CHAN_STAT_MS_CHANGED_MASK	(RP2_CHAN_STAT_DSR_CHANGED_m | \
					 RP2_CHAN_STAT_CTS_CHANGED_m | \
					 RP2_CHAN_STAT_CD_CHANGED_m | \
					 RP2_CHAN_STAT_RI_CHANGED_m)

#define RP2_TXRX_CTL			0x014
#define RP2_TXRX_CTL_MSRIRQ_m		BIT(0)
#define RP2_TXRX_CTL_RXIRQ_m		BIT(2)
#define RP2_TXRX_CTL_RX_TRIG_s		3
#define RP2_TXRX_CTL_RX_TRIG_m		(0x3 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_RX_TRIG_1		(0x1 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_RX_TRIG_256	(0x2 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_RX_TRIG_448	(0x3 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_RX_EN_m		BIT(5)
#define RP2_TXRX_CTL_RTSFLOW_m		BIT(6)
#define RP2_TXRX_CTL_DTRFLOW_m		BIT(7)
#define RP2_TXRX_CTL_TX_TRIG_s		16
#define RP2_TXRX_CTL_TX_TRIG_m		(0x3 << RP2_TXRX_CTL_RX_TRIG_s)
#define RP2_TXRX_CTL_DSRFLOW_m		BIT(18)
#define RP2_TXRX_CTL_TXIRQ_m		BIT(19)
#define RP2_TXRX_CTL_CTSFLOW_m		BIT(23)
#define RP2_TXRX_CTL_TX_EN_m		BIT(24)
#define RP2_TXRX_CTL_RTS_m		BIT(25)
#define RP2_TXRX_CTL_DTR_m		BIT(26)
#define RP2_TXRX_CTL_LOOP_m		BIT(27)
#define RP2_TXRX_CTL_BREAK_m		BIT(28)
#define RP2_TXRX_CTL_CMSPAR_m		BIT(29)
#define RP2_TXRX_CTL_nPARODD_m		BIT(30)
#define RP2_TXRX_CTL_PARENB_m		BIT(31)

#define RP2_UART_CTL			0x018
#define RP2_UART_CTL_MODE_s		0
#define RP2_UART_CTL_MODE_m		(0x7 << RP2_UART_CTL_MODE_s)
#define RP2_UART_CTL_MODE_rs232		(0x1 << RP2_UART_CTL_MODE_s)
#define RP2_UART_CTL_FLUSH_RX_m		BIT(3)
#define RP2_UART_CTL_FLUSH_TX_m		BIT(4)
#define RP2_UART_CTL_RESET_CH_m		BIT(5)
#define RP2_UART_CTL_XMIT_EN_m		BIT(6)
#define RP2_UART_CTL_DATABITS_s		8
#define RP2_UART_CTL_DATABITS_m		(0x3 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_DATABITS_8		(0x3 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_DATABITS_7		(0x2 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_DATABITS_6		(0x1 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_DATABITS_5		(0x0 << RP2_UART_CTL_DATABITS_s)
#define RP2_UART_CTL_STOPBITS_m		BIT(10)

#define RP2_BAUD			0x01c

/* ucode registers */
#define RP2_TX_SWFLOW			0x02
#define RP2_TX_SWFLOW_ena		0x81
#define RP2_TX_SWFLOW_dis		0x9d

#define RP2_RX_SWFLOW			0x0c
#define RP2_RX_SWFLOW_ena		0x81
#define RP2_RX_SWFLOW_dis		0x8d

#define RP2_RX_FIFO			0x37
#define RP2_RX_FIFO_ena			0x08
#define RP2_RX_FIFO_dis			0x81

static struct uart_driver rp2_uart_driver = {
	.owner				= THIS_MODULE,
	.driver_name			= DRV_NAME,
	.dev_name			= "ttyRP",
	.nr				= CONFIG_SERIAL_RP2_NR_UARTS,
};

struct rp2_card;

struct rp2_uart_port {
	struct uart_port		port;
	int				idx;
	int				ignore_rx;
	struct rp2_card			*card;
	void __iomem			*asic_base;
	void __iomem			*base;
	void __iomem			*ucode;
};

struct rp2_card {
	struct pci_dev			*pdev;
	struct rp2_uart_port		*ports;
	int				n_ports;
	int				initialized_ports;
	int				minor_start;
	int				smpte;
	void __iomem			*bar0;
	void __iomem			*bar1;
	spinlock_t			card_lock;
	struct completion		fw_loaded;
};

#define RP_ID(prod) PCI_VDEVICE(RP, (prod))
#define RP_CAP(ports, smpte) (((ports) << 8) | ((smpte) << 0))

static inline void rp2_decode_cap(const struct pci_device_id *id,
				  int *ports, int *smpte)
{
	*ports = id->driver_data >> 8;
	*smpte = id->driver_data & 0xff;
}

static DEFINE_SPINLOCK(rp2_minor_lock);
static int rp2_minor_next;

static int rp2_alloc_ports(int n_ports)
{
	int ret = -ENOSPC;

	spin_lock(&rp2_minor_lock);
	if (rp2_minor_next + n_ports <= CONFIG_SERIAL_RP2_NR_UARTS) {
		/* sorry, no support for hot unplugging individual cards */
		ret = rp2_minor_next;
		rp2_minor_next += n_ports;
	}
	spin_unlock(&rp2_minor_lock);

	return ret;
}

static inline struct rp2_uart_port *port_to_up(struct uart_port *port)
{
	return container_of(port, struct rp2_uart_port, port);
}

static void rp2_rmw(struct rp2_uart_port *up, int reg,
		    u32 clr_bits, u32 set_bits)
{
	u32 tmp = readl(up->base + reg);
	tmp &= ~clr_bits;
	tmp |= set_bits;
	writel(tmp, up->base + reg);
}

static void rp2_rmw_clr(struct rp2_uart_port *up, int reg, u32 val)
{
	rp2_rmw(up, reg, val, 0);
}

static void rp2_rmw_set(struct rp2_uart_port *up, int reg, u32 val)
{
	rp2_rmw(up, reg, 0, val);
}

static void rp2_mask_ch_irq(struct rp2_uart_port *up, int ch_num,
			    int is_enabled)
{
	unsigned long flags, irq_mask;

	spin_lock_irqsave(&up->card->card_lock, flags);

	irq_mask = readl(up->asic_base + RP2_CH_IRQ_MASK);
	if (is_enabled)
		irq_mask &= ~BIT(ch_num);
	else
		irq_mask |= BIT(ch_num);
	writel(irq_mask, up->asic_base + RP2_CH_IRQ_MASK);

	spin_unlock_irqrestore(&up->card->card_lock, flags);
}

static unsigned int rp2_uart_tx_empty(struct uart_port *port)
{
	struct rp2_uart_port *up = port_to_up(port);
	unsigned long tx_fifo_bytes, flags;

	/*
	 * This should probably check the transmitter, not the FIFO.
	 * But the TXEMPTY bit doesn't seem to work unless the TX IRQ is
	 * enabled.
	 */
	spin_lock_irqsave(&up->port.lock, flags);
	tx_fifo_bytes = readw(up->base + RP2_TX_FIFO_COUNT);
	spin_unlock_irqrestore(&up->port.lock, flags);

	return tx_fifo_bytes ? 0 : TIOCSER_TEMT;
}

static unsigned int rp2_uart_get_mctrl(struct uart_port *port)
{
	struct rp2_uart_port *up = port_to_up(port);
	u32 status;

	status = readl(up->base + RP2_CHAN_STAT);
	return ((status & RP2_CHAN_STAT_DCD_m) ? TIOCM_CAR : 0) |
	       ((status & RP2_CHAN_STAT_DSR_m) ? TIOCM_DSR : 0) |
	       ((status & RP2_CHAN_STAT_CTS_m) ? TIOCM_CTS : 0) |
	       ((status & RP2_CHAN_STAT_RI_m) ? TIOCM_RI : 0);
}

static void rp2_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
	rp2_rmw(port_to_up(port), RP2_TXRX_CTL,
		RP2_TXRX_CTL_DTR_m | RP2_TXRX_CTL_RTS_m | RP2_TXRX_CTL_LOOP_m,
		((mctrl & TIOCM_DTR) ? RP2_TXRX_CTL_DTR_m : 0) |
		((mctrl & TIOCM_RTS) ? RP2_TXRX_CTL_RTS_m : 0) |
		((mctrl & TIOCM_LOOP) ? RP2_TXRX_CTL_LOOP_m : 0));
}

static void rp2_uart_start_tx(struct uart_port *port)
{
	rp2_rmw_set(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_TXIRQ_m);
}

static void rp2_uart_stop_tx(struct uart_port *port)
{
	rp2_rmw_clr(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_TXIRQ_m);
}

static void rp2_uart_stop_rx(struct uart_port *port)
{
	rp2_rmw_clr(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_RXIRQ_m);
}

static void rp2_uart_break_ctl(struct uart_port *port, int break_state)
{
	unsigned long flags;

	spin_lock_irqsave(&port->lock, flags);
	rp2_rmw(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_BREAK_m,
		break_state ? RP2_TXRX_CTL_BREAK_m : 0);
	spin_unlock_irqrestore(&port->lock, flags);
}

static void rp2_uart_enable_ms(struct uart_port *port)
{
	rp2_rmw_set(port_to_up(port), RP2_TXRX_CTL, RP2_TXRX_CTL_MSRIRQ_m);
}

static void __rp2_uart_set_termios(struct rp2_uart_port *up,
				   unsigned long cfl,
				   unsigned long ifl,
				   unsigned int baud_div)
{
	/* baud rate divisor (calculated elsewhere).  0 = divide-by-1 */
	writew(baud_div - 1, up->base + RP2_BAUD);

	/* data bits and stop bits */
	rp2_rmw(up, RP2_UART_CTL,
		RP2_UART_CTL_STOPBITS_m | RP2_UART_CTL_DATABITS_m,
		((cfl & CSTOPB) ? RP2_UART_CTL_STOPBITS_m : 0) |
		(((cfl & CSIZE) == CS8) ? RP2_UART_CTL_DATABITS_8 : 0) |
		(((cfl & CSIZE) == CS7) ? RP2_UART_CTL_DATABITS_7 : 0) |
		(((cfl & CSIZE) == CS6) ? RP2_UART_CTL_DATABITS_6 : 0) |
		(((cfl & CSIZE) == CS5) ? RP2_UART_CTL_DATABITS_5 : 0));

	/* parity and hardware flow control */
	rp2_rmw(up, RP2_TXRX_CTL,
		RP2_TXRX_CTL_PARENB_m | RP2_TXRX_CTL_nPARODD_m |
		RP2_TXRX_CTL_CMSPAR_m | RP2_TXRX_CTL_DTRFLOW_m |
		RP2_TXRX_CTL_DSRFLOW_m | RP2_TXRX_CTL_RTSFLOW_m |
		RP2_TXRX_CTL_CTSFLOW_m,
		((cfl & PARENB) ? RP2_TXRX_CTL_PARENB_m : 0) |
		((cfl & PARODD) ? 0 : RP2_TXRX_CTL_nPARODD_m) |
		((cfl & CMSPAR) ? RP2_TXRX_CTL_CMSPAR_m : 0) |
		((cfl & CRTSCTS) ? (RP2_TXRX_CTL_RTSFLOW_m |
				    RP2_TXRX_CTL_CTSFLOW_m) : 0));

	/* XON/XOFF software flow control */
	writeb((ifl & IXON) ? RP2_TX_SWFLOW_ena : RP2_TX_SWFLOW_dis,
	       up->ucode + RP2_TX_SWFLOW);
	writeb((ifl & IXOFF) ? RP2_RX_SWFLOW_ena : RP2_RX_SWFLOW_dis,
	       up->ucode + RP2_RX_SWFLOW);
}

static void rp2_uart_set_termios(struct uart_port *port,
				 struct ktermios *new,
				 struct ktermios *old)
{
	struct rp2_uart_port *up = port_to_up(port);
	unsigned long flags;
	unsigned int baud, baud_div;

	baud = uart_get_baud_rate(port, new, old, 0, port->uartclk / 16);
	baud_div = uart_get_divisor(port, baud);

	if (tty_termios_baud_rate(new))
		tty_termios_encode_baud_rate(new, baud, baud);

	spin_lock_irqsave(&port->lock, flags);

	/* ignore all characters if CREAD is not set */
	port->ignore_status_mask = (new->c_cflag & CREAD) ? 0 : RP2_DUMMY_READ;

	__rp2_uart_set_termios(up, new->c_cflag, new->c_iflag, baud_div);
	uart_update_timeout(port, new->c_cflag, baud);

	spin_unlock_irqrestore(&port->lock, flags);
}

static void rp2_rx_chars(struct rp2_uart_port *up)
{
	u16 bytes = readw(up->base + RP2_RX_FIFO_COUNT);
	struct tty_port *port = &up->port.state->port;

	for (; bytes != 0; bytes--) {
		u32 byte = readw(up->base + RP2_DATA_BYTE) | RP2_DUMMY_READ;
		char ch = byte & 0xff;

		if (likely(!(byte & RP2_DATA_BYTE_EXCEPTION_MASK))) {
			if (!uart_handle_sysrq_char(&up->port, ch))
				uart_insert_char(&up->port, byte, 0, ch,
						 TTY_NORMAL);
		} else {
			char flag = TTY_NORMAL;

			if (byte & RP2_DATA_BYTE_BREAK_m)
				flag = TTY_BREAK;
			else if (byte & RP2_DATA_BYTE_ERR_FRAMING_m)
				flag = TTY_FRAME;
			else if (byte & RP2_DATA_BYTE_ERR_PARITY_m)
				flag = TTY_PARITY;
			uart_insert_char(&up->port, byte,
					 RP2_DATA_BYTE_ERR_OVERRUN_m, ch, flag);
		}
		up->port.icount.rx++;
	}

	spin_unlock(&up->port.lock);
	tty_flip_buffer_push(port);
	spin_lock(&up->port.lock);
}

static void rp2_tx_chars(struct rp2_uart_port *up)
{
	u16 max_tx = FIFO_SIZE - readw(up->base + RP2_TX_FIFO_COUNT);
	struct circ_buf *xmit = &up->port.state->xmit;

	if (uart_tx_stopped(&up->port)) {
		rp2_uart_stop_tx(&up->port);
		return;
	}

	for (; max_tx != 0; max_tx--) {
		if (up->port.x_char) {
			writeb(up->port.x_char, up->base + RP2_DATA_BYTE);
			up->port.x_char = 0;
			up->port.icount.tx++;
			continue;
		}
		if (uart_circ_empty(xmit)) {
			rp2_uart_stop_tx(&up->port);
			break;
		}
		writeb(xmit->buf[xmit->tail], up->base + RP2_DATA_BYTE);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		up->port.icount.tx++;
	}

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(&up->port);
}

static void rp2_ch_interrupt(struct rp2_uart_port *up)
{
	u32 status;

	spin_lock(&up->port.lock);

	/*
	 * The IRQ status bits are clear-on-write.  Other status bits in
	 * this register aren't, so it's harmless to write to them.
	 */
	status = readl(up->base + RP2_CHAN_STAT);
	writel(status, up->base + RP2_CHAN_STAT);

	if (status & RP2_CHAN_STAT_RXDATA_m)
		rp2_rx_chars(up);
	if (status & RP2_CHAN_STAT_TXEMPTY_m)
		rp2_tx_chars(up);
	if (status & RP2_CHAN_STAT_MS_CHANGED_MASK)
		wake_up_interruptible(&up->port.state->port.delta_msr_wait);

	spin_unlock(&up->port.lock);
}

static int rp2_asic_interrupt(struct rp2_card *card, unsigned int asic_id)
{
	void __iomem *base = card->bar1 + RP2_ASIC_OFFSET(asic_id);
	int ch, handled = 0;
	unsigned long status = readl(base + RP2_CH_IRQ_STAT) &
			       ~readl(base + RP2_CH_IRQ_MASK);

	for_each_set_bit(ch, &status, PORTS_PER_ASIC) {
		rp2_ch_interrupt(&card->ports[ch]);
		handled++;
	}
	return handled;
}

static irqreturn_t rp2_uart_interrupt(int irq, void *dev_id)
{
	struct rp2_card *card = dev_id;
	int handled;

	handled = rp2_asic_interrupt(card, 0);
	if (card->n_ports >= PORTS_PER_ASIC)
		handled += rp2_asic_interrupt(card, 1);

	return handled ? IRQ_HANDLED : IRQ_NONE;
}

static inline void rp2_flush_fifos(struct rp2_uart_port *up)
{
	rp2_rmw_set(up, RP2_UART_CTL,
		    RP2_UART_CTL_FLUSH_RX_m | RP2_UART_CTL_FLUSH_TX_m);
	readl(up->base + RP2_UART_CTL);
	udelay(10);
	rp2_rmw_clr(up, RP2_UART_CTL,
		    RP2_UART_CTL_FLUSH_RX_m | RP2_UART_CTL_FLUSH_TX_m);
}

static int rp2_uart_startup(struct uart_port *port)
{
	struct rp2_uart_port *up = port_to_up(port);

	rp2_flush_fifos(up);
	rp2_rmw(up, RP2_TXRX_CTL, RP2_TXRX_CTL_MSRIRQ_m, RP2_TXRX_CTL_RXIRQ_m);
	rp2_rmw(up, RP2_TXRX_CTL, RP2_TXRX_CTL_RX_TRIG_m,
		RP2_TXRX_CTL_RX_TRIG_1);
	rp2_rmw(up, RP2_CHAN_STAT, 0, 0);
	rp2_mask_ch_irq(up, up->idx, 1);

	return 0;
}

static void rp2_uart_shutdown(struct uart_port *port)
{
	struct rp2_uart_port *up = port_to_up(port);
	unsigned long flags;

	rp2_uart_break_ctl(port, 0);

	spin_lock_irqsave(&port->lock, flags);
	rp2_mask_ch_irq(up, up->idx, 0);
	rp2_rmw(up, RP2_CHAN_STAT, 0, 0);
	spin_unlock_irqrestore(&port->lock, flags);
}

static const char *rp2_uart_type(struct uart_port *port)
{
	return (port->type == PORT_RP2) ? "RocketPort 2 UART" : NULL;
}

static void rp2_uart_release_port(struct uart_port *port)
{
	/* Nothing to release ... */
}

static int rp2_uart_request_port(struct uart_port *port)
{
	/* UARTs always present */
	return 0;
}

static void rp2_uart_config_port(struct uart_port *port, int flags)
{
	if (flags & UART_CONFIG_TYPE)
		port->type = PORT_RP2;
}

static int rp2_uart_verify_port(struct uart_port *port,
				   struct serial_struct *ser)
{
	if (ser->type != PORT_UNKNOWN && ser->type != PORT_RP2)
		return -EINVAL;

	return 0;
}

static const struct uart_ops rp2_uart_ops = {
	.tx_empty	= rp2_uart_tx_empty,
	.set_mctrl	= rp2_uart_set_mctrl,
	.get_mctrl	= rp2_uart_get_mctrl,
	.stop_tx	= rp2_uart_stop_tx,
	.start_tx	= rp2_uart_start_tx,
	.stop_rx	= rp2_uart_stop_rx,
	.enable_ms	= rp2_uart_enable_ms,
	.break_ctl	= rp2_uart_break_ctl,
	.startup	= rp2_uart_startup,
	.shutdown	= rp2_uart_shutdown,
	.set_termios	= rp2_uart_set_termios,
	.type		= rp2_uart_type,
	.release_port	= rp2_uart_release_port,
	.request_port	= rp2_uart_request_port,
	.config_port	= rp2_uart_config_port,
	.verify_port	= rp2_uart_verify_port,
};

static void rp2_reset_asic(struct rp2_card *card, unsigned int asic_id)
{
	void __iomem *base = card->bar1 + RP2_ASIC_OFFSET(asic_id);
	u32 clk_cfg;

	writew(1, base + RP2_GLOBAL_CMD);
	readw(base + RP2_GLOBAL_CMD);
	msleep(100);
	writel(0, base + RP2_CLK_PRESCALER);

	/* TDM clock configuration */
	clk_cfg = readw(base + RP2_ASIC_CFG);
	clk_cfg = (clk_cfg & ~BIT(8)) | BIT(9);
	writew(clk_cfg, base + RP2_ASIC_CFG);

	/* IRQ routing */
	writel(ALL_PORTS_MASK, base + RP2_CH_IRQ_MASK);
	writel(RP2_ASIC_IRQ_EN_m, base + RP2_ASIC_IRQ);
}

static void rp2_init_card(struct rp2_card *card)
{
	writel(4, card->bar0 + RP2_FPGA_CTL0);
	writel(0, card->bar0 + RP2_FPGA_CTL1);

	rp2_reset_asic(card, 0);
	if (card->n_ports >= PORTS_PER_ASIC)
		rp2_reset_asic(card, 1);

	writel(RP2_IRQ_MASK_EN_m, card->bar0 + RP2_IRQ_MASK);
}

static void rp2_init_port(struct rp2_uart_port *up, const struct firmware *fw)
{
	int i;

	writel(RP2_UART_CTL_RESET_CH_m, up->base + RP2_UART_CTL);
	readl(up->base + RP2_UART_CTL);
	udelay(1);

	writel(0, up->base + RP2_TXRX_CTL);
	writel(0, up->base + RP2_UART_CTL);
	readl(up->base + RP2_UART_CTL);
	udelay(1);

	rp2_flush_fifos(up);

	for (i = 0; i < min_t(int, fw->size, RP2_UCODE_BYTES); i++)
		writeb(fw->data[i], up->ucode + i);

	__rp2_uart_set_termios(up, CS8 | CREAD | CLOCAL, 0, DEFAULT_BAUD_DIV);
	rp2_uart_set_mctrl(&up->port, 0);

	writeb(RP2_RX_FIFO_ena, up->ucode + RP2_RX_FIFO);
	rp2_rmw(up, RP2_UART_CTL, RP2_UART_CTL_MODE_m,
		RP2_UART_CTL_XMIT_EN_m | RP2_UART_CTL_MODE_rs232);
	rp2_rmw_set(up, RP2_TXRX_CTL,
		    RP2_TXRX_CTL_TX_EN_m | RP2_TXRX_CTL_RX_EN_m);
}

static void rp2_remove_ports(struct rp2_card *card)
{
	int i;

	for (i = 0; i < card->initialized_ports; i++)
		uart_remove_one_port(&rp2_uart_driver, &card->ports[i].port);
	card->initialized_ports = 0;
}

static void rp2_fw_cb(const struct firmware *fw, void *context)
{
	struct rp2_card *card = context;
	resource_size_t phys_base;
	int i, rc = -ENOENT;

	if (!fw) {
		dev_err(&card->pdev->dev, "cannot find '%s' firmware image\n",
			RP2_FW_NAME);
		goto no_fw;
	}

	phys_base = pci_resource_start(card->pdev, 1);

	for (i = 0; i < card->n_ports; i++) {
		struct rp2_uart_port *rp = &card->ports[i];
		struct uart_port *p;
		int j = (unsigned)i % PORTS_PER_ASIC;

		rp->asic_base = card->bar1;
		rp->base = card->bar1 + RP2_PORT_BASE + j*RP2_PORT_SPACING;
		rp->ucode = card->bar1 + RP2_UCODE_BASE + j*RP2_UCODE_SPACING;
		rp->card = card;
		rp->idx = j;

		p = &rp->port;
		p->line = card->minor_start + i;
		p->dev = &card->pdev->dev;
		p->type = PORT_RP2;
		p->iotype = UPIO_MEM32;
		p->uartclk = UART_CLOCK;
		p->regshift = 2;
		p->fifosize = FIFO_SIZE;
		p->ops = &rp2_uart_ops;
		p->irq = card->pdev->irq;
		p->membase = rp->base;
		p->mapbase = phys_base + RP2_PORT_BASE + j*RP2_PORT_SPACING;

		if (i >= PORTS_PER_ASIC) {
			rp->asic_base += RP2_ASIC_SPACING;
			rp->base += RP2_ASIC_SPACING;
			rp->ucode += RP2_ASIC_SPACING;
			p->mapbase += RP2_ASIC_SPACING;
		}

		rp2_init_port(rp, fw);
		rc = uart_add_one_port(&rp2_uart_driver, p);
		if (rc) {
			dev_err(&card->pdev->dev,
				"error registering port %d: %d\n", i, rc);
			rp2_remove_ports(card);
			break;
		}
		card->initialized_ports++;
	}

	release_firmware(fw);
no_fw:
	/*
	 * rp2_fw_cb() is called from a workqueue long after rp2_probe()
	 * has already returned success.  So if something failed here,
	 * we'll just leave the now-dormant device in place until somebody
	 * unbinds it.
	 */
	if (rc)
		dev_warn(&card->pdev->dev, "driver initialization failed\n");

	complete(&card->fw_loaded);
}

static int rp2_probe(struct pci_dev *pdev,
				   const struct pci_device_id *id)
{
	struct rp2_card *card;
	struct rp2_uart_port *ports;
	void __iomem * const *bars;
	int rc;

	card = devm_kzalloc(&pdev->dev, sizeof(*card), GFP_KERNEL);
	if (!card)
		return -ENOMEM;
	pci_set_drvdata(pdev, card);
	spin_lock_init(&card->card_lock);
	init_completion(&card->fw_loaded);

	rc = pcim_enable_device(pdev);
	if (rc)
		return rc;

	rc = pcim_iomap_regions_request_all(pdev, 0x03, DRV_NAME);
	if (rc)
		return rc;

	bars = pcim_iomap_table(pdev);
	card->bar0 = bars[0];
	card->bar1 = bars[1];
	card->pdev = pdev;

	rp2_decode_cap(id, &card->n_ports, &card->smpte);
	dev_info(&pdev->dev, "found new card with %d ports\n", card->n_ports);

	card->minor_start = rp2_alloc_ports(card->n_ports);
	if (card->minor_start < 0) {
		dev_err(&pdev->dev,
			"too many ports (try increasing CONFIG_SERIAL_RP2_NR_UARTS)\n");
		return -EINVAL;
	}

	rp2_init_card(card);

	ports = devm_kzalloc(&pdev->dev, sizeof(*ports) * card->n_ports,
			     GFP_KERNEL);
	if (!ports)
		return -ENOMEM;
	card->ports = ports;

	rc = devm_request_irq(&pdev->dev, pdev->irq, rp2_uart_interrupt,
			      IRQF_SHARED, DRV_NAME, card);
	if (rc)
		return rc;

	/*
	 * Only catastrophic errors (e.g. ENOMEM) are reported here.
	 * If the FW image is missing, we'll find out in rp2_fw_cb()
	 * and print an error message.
	 */
	rc = request_firmware_nowait(THIS_MODULE, 1, RP2_FW_NAME, &pdev->dev,
				     GFP_KERNEL, card, rp2_fw_cb);
	if (rc)
		return rc;
	dev_dbg(&pdev->dev, "waiting for firmware blob...\n");

	return 0;
}

static void rp2_remove(struct pci_dev *pdev)
{
	struct rp2_card *card = pci_get_drvdata(pdev);

	wait_for_completion(&card->fw_loaded);
	rp2_remove_ports(card);
}

static const struct pci_device_id rp2_pci_tbl[] = {

	/* RocketPort INFINITY cards */

	{ RP_ID(0x0040), RP_CAP(8,  0) }, /* INF Octa, RJ45, selectable */
	{ RP_ID(0x0041), RP_CAP(32, 0) }, /* INF 32, ext interface */
	{ RP_ID(0x0042), RP_CAP(8,  0) }, /* INF Octa, ext interface */
	{ RP_ID(0x0043), RP_CAP(16, 0) }, /* INF 16, ext interface */
	{ RP_ID(0x0044), RP_CAP(4,  0) }, /* INF Quad, DB, selectable */
	{ RP_ID(0x0045), RP_CAP(8,  0) }, /* INF Octa, DB, selectable */
	{ RP_ID(0x0046), RP_CAP(4,  0) }, /* INF Quad, ext interface */
	{ RP_ID(0x0047), RP_CAP(4,  0) }, /* INF Quad, RJ45 */
	{ RP_ID(0x004a), RP_CAP(4,  0) }, /* INF Plus, Quad */
	{ RP_ID(0x004b), RP_CAP(8,  0) }, /* INF Plus, Octa */
	{ RP_ID(0x004c), RP_CAP(8,  0) }, /* INF III, Octa */
	{ RP_ID(0x004d), RP_CAP(4,  0) }, /* INF III, Quad */
	{ RP_ID(0x004e), RP_CAP(2,  0) }, /* INF Plus, 2, RS232 */
	{ RP_ID(0x004f), RP_CAP(2,  1) }, /* INF Plus, 2, SMPTE */
	{ RP_ID(0x0050), RP_CAP(4,  0) }, /* INF Plus, Quad, RJ45 */
	{ RP_ID(0x0051), RP_CAP(8,  0) }, /* INF Plus, Octa, RJ45 */
	{ RP_ID(0x0052), RP_CAP(8,  1) }, /* INF Octa, SMPTE */

	/* RocketPort EXPRESS cards */

	{ RP_ID(0x0060), RP_CAP(8,  0) }, /* EXP Octa, RJ45, selectable */
	{ RP_ID(0x0061), RP_CAP(32, 0) }, /* EXP 32, ext interface */
	{ RP_ID(0x0062), RP_CAP(8,  0) }, /* EXP Octa, ext interface */
	{ RP_ID(0x0063), RP_CAP(16, 0) }, /* EXP 16, ext interface */
	{ RP_ID(0x0064), RP_CAP(4,  0) }, /* EXP Quad, DB, selectable */
	{ RP_ID(0x0065), RP_CAP(8,  0) }, /* EXP Octa, DB, selectable */
	{ RP_ID(0x0066), RP_CAP(4,  0) }, /* EXP Quad, ext interface */
	{ RP_ID(0x0067), RP_CAP(4,  0) }, /* EXP Quad, RJ45 */
	{ RP_ID(0x0068), RP_CAP(8,  0) }, /* EXP Octa, RJ11 */
	{ RP_ID(0x0072), RP_CAP(8,  1) }, /* EXP Octa, SMPTE */
	{ }
};
MODULE_DEVICE_TABLE(pci, rp2_pci_tbl);

static struct pci_driver rp2_pci_driver = {
	.name		= DRV_NAME,
	.id_table	= rp2_pci_tbl,
	.probe		= rp2_probe,
	.remove		= rp2_remove,
};

static int __init rp2_uart_init(void)
{
	int rc;

	rc = uart_register_driver(&rp2_uart_driver);
	if (rc)
		return rc;

	rc = pci_register_driver(&rp2_pci_driver);
	if (rc) {
		uart_unregister_driver(&rp2_uart_driver);
		return rc;
	}

	return 0;
}

static void __exit rp2_uart_exit(void)
{
	pci_unregister_driver(&rp2_pci_driver);
	uart_unregister_driver(&rp2_uart_driver);
}

module_init(rp2_uart_init);
module_exit(rp2_uart_exit);

MODULE_DESCRIPTION("Comtrol RocketPort EXPRESS/INFINITY driver");
MODULE_AUTHOR("Kevin Cernekee <cernekee@gmail.com>");
MODULE_LICENSE("GPL v2");
MODULE_FIRMWARE(RP2_FW_NAME);