xref: /linux/drivers/net/wan/n2.c (revision 6ee738610f41b59733f63718f0bdbcba7d3a3f12)
1 /*
2  * SDL Inc. RISCom/N2 synchronous serial card driver for Linux
3  *
4  * Copyright (C) 1998-2003 Krzysztof Halasa <khc@pm.waw.pl>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of version 2 of the GNU General Public License
8  * as published by the Free Software Foundation.
9  *
10  * For information see <http://www.kernel.org/pub/linux/utils/net/hdlc/>
11  *
12  * Note: integrated CSU/DSU/DDS are not supported by this driver
13  *
14  * Sources of information:
15  *    Hitachi HD64570 SCA User's Manual
16  *    SDL Inc. PPP/HDLC/CISCO driver
17  */
18 
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/capability.h>
22 #include <linux/slab.h>
23 #include <linux/types.h>
24 #include <linux/fcntl.h>
25 #include <linux/in.h>
26 #include <linux/string.h>
27 #include <linux/errno.h>
28 #include <linux/init.h>
29 #include <linux/ioport.h>
30 #include <linux/moduleparam.h>
31 #include <linux/netdevice.h>
32 #include <linux/hdlc.h>
33 #include <asm/io.h>
34 #include "hd64570.h"
35 
36 
37 static const char* version = "SDL RISCom/N2 driver version: 1.15";
38 static const char* devname = "RISCom/N2";
39 
40 #undef DEBUG_PKT
41 #define DEBUG_RINGS
42 
43 #define USE_WINDOWSIZE 16384
44 #define USE_BUS16BITS 1
45 #define CLOCK_BASE 9830400	/* 9.8304 MHz */
46 #define MAX_PAGES      16	/* 16 RAM pages at max */
47 #define MAX_RAM_SIZE 0x80000	/* 512 KB */
48 #if MAX_RAM_SIZE > MAX_PAGES * USE_WINDOWSIZE
49 #undef MAX_RAM_SIZE
50 #define MAX_RAM_SIZE (MAX_PAGES * USE_WINDOWSIZE)
51 #endif
52 #define N2_IOPORTS 0x10
53 #define NEED_DETECT_RAM
54 #define NEED_SCA_MSCI_INTR
55 #define MAX_TX_BUFFERS 10
56 
57 static char *hw;	/* pointer to hw=xxx command line string */
58 
59 /* RISCom/N2 Board Registers */
60 
61 /* PC Control Register */
62 #define N2_PCR 0
63 #define PCR_RUNSCA 1     /* Run 64570 */
64 #define PCR_VPM    2     /* Enable VPM - needed if using RAM above 1 MB */
65 #define PCR_ENWIN  4     /* Open window */
66 #define PCR_BUS16  8     /* 16-bit bus */
67 
68 
69 /* Memory Base Address Register */
70 #define N2_BAR 2
71 
72 
73 /* Page Scan Register  */
74 #define N2_PSR 4
75 #define WIN16K       0x00
76 #define WIN32K       0x20
77 #define WIN64K       0x40
78 #define PSR_WINBITS  0x60
79 #define PSR_DMAEN    0x80
80 #define PSR_PAGEBITS 0x0F
81 
82 
83 /* Modem Control Reg */
84 #define N2_MCR 6
85 #define CLOCK_OUT_PORT1 0x80
86 #define CLOCK_OUT_PORT0 0x40
87 #define TX422_PORT1     0x20
88 #define TX422_PORT0     0x10
89 #define DSR_PORT1       0x08
90 #define DSR_PORT0       0x04
91 #define DTR_PORT1       0x02
92 #define DTR_PORT0       0x01
93 
94 
95 typedef struct port_s {
96 	struct net_device *dev;
97 	struct card_s *card;
98 	spinlock_t lock;	/* TX lock */
99 	sync_serial_settings settings;
100 	int valid;		/* port enabled */
101 	int rxpart;		/* partial frame received, next frame invalid*/
102 	unsigned short encoding;
103 	unsigned short parity;
104 	u16 rxin;		/* rx ring buffer 'in' pointer */
105 	u16 txin;		/* tx ring buffer 'in' and 'last' pointers */
106 	u16 txlast;
107 	u8 rxs, txs, tmc;	/* SCA registers */
108 	u8 phy_node;		/* physical port # - 0 or 1 */
109 	u8 log_node;		/* logical port # */
110 }port_t;
111 
112 
113 
114 typedef struct card_s {
115 	u8 __iomem *winbase;		/* ISA window base address */
116 	u32 phy_winbase;	/* ISA physical base address */
117 	u32 ram_size;		/* number of bytes */
118 	u16 io;			/* IO Base address */
119 	u16 buff_offset;	/* offset of first buffer of first channel */
120 	u16 rx_ring_buffers;	/* number of buffers in a ring */
121 	u16 tx_ring_buffers;
122 	u8 irq;			/* IRQ (3-15) */
123 
124 	port_t ports[2];
125 	struct card_s *next_card;
126 }card_t;
127 
128 
129 static card_t *first_card;
130 static card_t **new_card = &first_card;
131 
132 
133 #define sca_reg(reg, card) (0x8000 | (card)->io | \
134 			    ((reg) & 0x0F) | (((reg) & 0xF0) << 6))
135 #define sca_in(reg, card)		inb(sca_reg(reg, card))
136 #define sca_out(value, reg, card)	outb(value, sca_reg(reg, card))
137 #define sca_inw(reg, card)		inw(sca_reg(reg, card))
138 #define sca_outw(value, reg, card)	outw(value, sca_reg(reg, card))
139 
140 #define port_to_card(port)		((port)->card)
141 #define log_node(port)			((port)->log_node)
142 #define phy_node(port)			((port)->phy_node)
143 #define winsize(card)			(USE_WINDOWSIZE)
144 #define winbase(card)      	     	((card)->winbase)
145 #define get_port(card, port)		((card)->ports[port].valid ? \
146 					 &(card)->ports[port] : NULL)
147 
148 
149 static __inline__ u8 sca_get_page(card_t *card)
150 {
151 	return inb(card->io + N2_PSR) & PSR_PAGEBITS;
152 }
153 
154 
155 static __inline__ void openwin(card_t *card, u8 page)
156 {
157 	u8 psr = inb(card->io + N2_PSR);
158 	outb((psr & ~PSR_PAGEBITS) | page, card->io + N2_PSR);
159 }
160 
161 
162 #include "hd64570.c"
163 
164 
165 static void n2_set_iface(port_t *port)
166 {
167 	card_t *card = port->card;
168 	int io = card->io;
169 	u8 mcr = inb(io + N2_MCR);
170 	u8 msci = get_msci(port);
171 	u8 rxs = port->rxs & CLK_BRG_MASK;
172 	u8 txs = port->txs & CLK_BRG_MASK;
173 
174 	switch(port->settings.clock_type) {
175 	case CLOCK_INT:
176 		mcr |= port->phy_node ? CLOCK_OUT_PORT1 : CLOCK_OUT_PORT0;
177 		rxs |= CLK_BRG_RX; /* BRG output */
178 		txs |= CLK_RXCLK_TX; /* RX clock */
179 		break;
180 
181 	case CLOCK_TXINT:
182 		mcr |= port->phy_node ? CLOCK_OUT_PORT1 : CLOCK_OUT_PORT0;
183 		rxs |= CLK_LINE_RX; /* RXC input */
184 		txs |= CLK_BRG_TX; /* BRG output */
185 		break;
186 
187 	case CLOCK_TXFROMRX:
188 		mcr |= port->phy_node ? CLOCK_OUT_PORT1 : CLOCK_OUT_PORT0;
189 		rxs |= CLK_LINE_RX; /* RXC input */
190 		txs |= CLK_RXCLK_TX; /* RX clock */
191 		break;
192 
193 	default:		/* Clock EXTernal */
194 		mcr &= port->phy_node ? ~CLOCK_OUT_PORT1 : ~CLOCK_OUT_PORT0;
195 		rxs |= CLK_LINE_RX; /* RXC input */
196 		txs |= CLK_LINE_TX; /* TXC input */
197 	}
198 
199 	outb(mcr, io + N2_MCR);
200 	port->rxs = rxs;
201 	port->txs = txs;
202 	sca_out(rxs, msci + RXS, card);
203 	sca_out(txs, msci + TXS, card);
204 	sca_set_port(port);
205 }
206 
207 
208 
209 static int n2_open(struct net_device *dev)
210 {
211 	port_t *port = dev_to_port(dev);
212 	int io = port->card->io;
213 	u8 mcr = inb(io + N2_MCR) | (port->phy_node ? TX422_PORT1:TX422_PORT0);
214 	int result;
215 
216 	result = hdlc_open(dev);
217 	if (result)
218 		return result;
219 
220 	mcr &= port->phy_node ? ~DTR_PORT1 : ~DTR_PORT0; /* set DTR ON */
221 	outb(mcr, io + N2_MCR);
222 
223 	outb(inb(io + N2_PCR) | PCR_ENWIN, io + N2_PCR); /* open window */
224 	outb(inb(io + N2_PSR) | PSR_DMAEN, io + N2_PSR); /* enable dma */
225 	sca_open(dev);
226 	n2_set_iface(port);
227 	return 0;
228 }
229 
230 
231 
232 static int n2_close(struct net_device *dev)
233 {
234 	port_t *port = dev_to_port(dev);
235 	int io = port->card->io;
236 	u8 mcr = inb(io+N2_MCR) | (port->phy_node ? TX422_PORT1 : TX422_PORT0);
237 
238 	sca_close(dev);
239 	mcr |= port->phy_node ? DTR_PORT1 : DTR_PORT0; /* set DTR OFF */
240 	outb(mcr, io + N2_MCR);
241 	hdlc_close(dev);
242 	return 0;
243 }
244 
245 
246 
247 static int n2_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
248 {
249 	const size_t size = sizeof(sync_serial_settings);
250 	sync_serial_settings new_line;
251 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
252 	port_t *port = dev_to_port(dev);
253 
254 #ifdef DEBUG_RINGS
255 	if (cmd == SIOCDEVPRIVATE) {
256 		sca_dump_rings(dev);
257 		return 0;
258 	}
259 #endif
260 	if (cmd != SIOCWANDEV)
261 		return hdlc_ioctl(dev, ifr, cmd);
262 
263 	switch(ifr->ifr_settings.type) {
264 	case IF_GET_IFACE:
265 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
266 		if (ifr->ifr_settings.size < size) {
267 			ifr->ifr_settings.size = size; /* data size wanted */
268 			return -ENOBUFS;
269 		}
270 		if (copy_to_user(line, &port->settings, size))
271 			return -EFAULT;
272 		return 0;
273 
274 	case IF_IFACE_SYNC_SERIAL:
275 		if(!capable(CAP_NET_ADMIN))
276 			return -EPERM;
277 
278 		if (copy_from_user(&new_line, line, size))
279 			return -EFAULT;
280 
281 		if (new_line.clock_type != CLOCK_EXT &&
282 		    new_line.clock_type != CLOCK_TXFROMRX &&
283 		    new_line.clock_type != CLOCK_INT &&
284 		    new_line.clock_type != CLOCK_TXINT)
285 		return -EINVAL;	/* No such clock setting */
286 
287 		if (new_line.loopback != 0 && new_line.loopback != 1)
288 			return -EINVAL;
289 
290 		memcpy(&port->settings, &new_line, size); /* Update settings */
291 		n2_set_iface(port);
292 		return 0;
293 
294 	default:
295 		return hdlc_ioctl(dev, ifr, cmd);
296 	}
297 }
298 
299 
300 
301 static void n2_destroy_card(card_t *card)
302 {
303 	int cnt;
304 
305 	for (cnt = 0; cnt < 2; cnt++)
306 		if (card->ports[cnt].card) {
307 			struct net_device *dev = port_to_dev(&card->ports[cnt]);
308 			unregister_hdlc_device(dev);
309 		}
310 
311 	if (card->irq)
312 		free_irq(card->irq, card);
313 
314 	if (card->winbase) {
315 		iounmap(card->winbase);
316 		release_mem_region(card->phy_winbase, USE_WINDOWSIZE);
317 	}
318 
319 	if (card->io)
320 		release_region(card->io, N2_IOPORTS);
321 	if (card->ports[0].dev)
322 		free_netdev(card->ports[0].dev);
323 	if (card->ports[1].dev)
324 		free_netdev(card->ports[1].dev);
325 	kfree(card);
326 }
327 
328 static const struct net_device_ops n2_ops = {
329 	.ndo_open       = n2_open,
330 	.ndo_stop       = n2_close,
331 	.ndo_change_mtu = hdlc_change_mtu,
332 	.ndo_start_xmit = hdlc_start_xmit,
333 	.ndo_do_ioctl   = n2_ioctl,
334 };
335 
336 static int __init n2_run(unsigned long io, unsigned long irq,
337 			 unsigned long winbase, long valid0, long valid1)
338 {
339 	card_t *card;
340 	u8 cnt, pcr;
341 	int i;
342 
343 	if (io < 0x200 || io > 0x3FF || (io % N2_IOPORTS) != 0) {
344 		printk(KERN_ERR "n2: invalid I/O port value\n");
345 		return -ENODEV;
346 	}
347 
348 	if (irq < 3 || irq > 15 || irq == 6) /* FIXME */ {
349 		printk(KERN_ERR "n2: invalid IRQ value\n");
350 		return -ENODEV;
351 	}
352 
353 	if (winbase < 0xA0000 || winbase > 0xFFFFF || (winbase & 0xFFF) != 0) {
354 		printk(KERN_ERR "n2: invalid RAM value\n");
355 		return -ENODEV;
356 	}
357 
358 	card = kzalloc(sizeof(card_t), GFP_KERNEL);
359 	if (card == NULL) {
360 		printk(KERN_ERR "n2: unable to allocate memory\n");
361 		return -ENOBUFS;
362 	}
363 
364 	card->ports[0].dev = alloc_hdlcdev(&card->ports[0]);
365 	card->ports[1].dev = alloc_hdlcdev(&card->ports[1]);
366 	if (!card->ports[0].dev || !card->ports[1].dev) {
367 		printk(KERN_ERR "n2: unable to allocate memory\n");
368 		n2_destroy_card(card);
369 		return -ENOMEM;
370 	}
371 
372 	if (!request_region(io, N2_IOPORTS, devname)) {
373 		printk(KERN_ERR "n2: I/O port region in use\n");
374 		n2_destroy_card(card);
375 		return -EBUSY;
376 	}
377 	card->io = io;
378 
379 	if (request_irq(irq, &sca_intr, 0, devname, card)) {
380 		printk(KERN_ERR "n2: could not allocate IRQ\n");
381 		n2_destroy_card(card);
382 		return(-EBUSY);
383 	}
384 	card->irq = irq;
385 
386 	if (!request_mem_region(winbase, USE_WINDOWSIZE, devname)) {
387 		printk(KERN_ERR "n2: could not request RAM window\n");
388 		n2_destroy_card(card);
389 		return(-EBUSY);
390 	}
391 	card->phy_winbase = winbase;
392 	card->winbase = ioremap(winbase, USE_WINDOWSIZE);
393 	if (!card->winbase) {
394 		printk(KERN_ERR "n2: ioremap() failed\n");
395 		n2_destroy_card(card);
396 		return -EFAULT;
397 	}
398 
399 	outb(0, io + N2_PCR);
400 	outb(winbase >> 12, io + N2_BAR);
401 
402 	switch (USE_WINDOWSIZE) {
403 	case 16384:
404 		outb(WIN16K, io + N2_PSR);
405 		break;
406 
407 	case 32768:
408 		outb(WIN32K, io + N2_PSR);
409 		break;
410 
411 	case 65536:
412 		outb(WIN64K, io + N2_PSR);
413 		break;
414 
415 	default:
416 		printk(KERN_ERR "n2: invalid window size\n");
417 		n2_destroy_card(card);
418 		return -ENODEV;
419 	}
420 
421 	pcr = PCR_ENWIN | PCR_VPM | (USE_BUS16BITS ? PCR_BUS16 : 0);
422 	outb(pcr, io + N2_PCR);
423 
424 	card->ram_size = sca_detect_ram(card, card->winbase, MAX_RAM_SIZE);
425 
426 	/* number of TX + RX buffers for one port */
427 	i = card->ram_size / ((valid0 + valid1) * (sizeof(pkt_desc) +
428 						   HDLC_MAX_MRU));
429 
430 	card->tx_ring_buffers = min(i / 2, MAX_TX_BUFFERS);
431 	card->rx_ring_buffers = i - card->tx_ring_buffers;
432 
433 	card->buff_offset = (valid0 + valid1) * sizeof(pkt_desc) *
434 		(card->tx_ring_buffers + card->rx_ring_buffers);
435 
436 	printk(KERN_INFO "n2: RISCom/N2 %u KB RAM, IRQ%u, "
437 	       "using %u TX + %u RX packets rings\n", card->ram_size / 1024,
438 	       card->irq, card->tx_ring_buffers, card->rx_ring_buffers);
439 
440 	if (card->tx_ring_buffers < 1) {
441 		printk(KERN_ERR "n2: RAM test failed\n");
442 		n2_destroy_card(card);
443 		return -EIO;
444 	}
445 
446 	pcr |= PCR_RUNSCA;		/* run SCA */
447 	outb(pcr, io + N2_PCR);
448 	outb(0, io + N2_MCR);
449 
450 	sca_init(card, 0);
451 	for (cnt = 0; cnt < 2; cnt++) {
452 		port_t *port = &card->ports[cnt];
453 		struct net_device *dev = port_to_dev(port);
454 		hdlc_device *hdlc = dev_to_hdlc(dev);
455 
456 		if ((cnt == 0 && !valid0) || (cnt == 1 && !valid1))
457 			continue;
458 
459 		port->phy_node = cnt;
460 		port->valid = 1;
461 
462 		if ((cnt == 1) && valid0)
463 			port->log_node = 1;
464 
465 		spin_lock_init(&port->lock);
466 		dev->irq = irq;
467 		dev->mem_start = winbase;
468 		dev->mem_end = winbase + USE_WINDOWSIZE - 1;
469 		dev->tx_queue_len = 50;
470 		dev->netdev_ops = &n2_ops;
471 		hdlc->attach = sca_attach;
472 		hdlc->xmit = sca_xmit;
473 		port->settings.clock_type = CLOCK_EXT;
474 		port->card = card;
475 
476 		if (register_hdlc_device(dev)) {
477 			printk(KERN_WARNING "n2: unable to register hdlc "
478 			       "device\n");
479 			port->card = NULL;
480 			n2_destroy_card(card);
481 			return -ENOBUFS;
482 		}
483 		sca_init_port(port); /* Set up SCA memory */
484 
485 		printk(KERN_INFO "%s: RISCom/N2 node %d\n",
486 		       dev->name, port->phy_node);
487 	}
488 
489 	*new_card = card;
490 	new_card = &card->next_card;
491 
492 	return 0;
493 }
494 
495 
496 
497 static int __init n2_init(void)
498 {
499 	if (hw==NULL) {
500 #ifdef MODULE
501 		printk(KERN_INFO "n2: no card initialized\n");
502 #endif
503 		return -EINVAL;	/* no parameters specified, abort */
504 	}
505 
506 	printk(KERN_INFO "%s\n", version);
507 
508 	do {
509 		unsigned long io, irq, ram;
510 		long valid[2] = { 0, 0 }; /* Default = both ports disabled */
511 
512 		io = simple_strtoul(hw, &hw, 0);
513 
514 		if (*hw++ != ',')
515 			break;
516 		irq = simple_strtoul(hw, &hw, 0);
517 
518 		if (*hw++ != ',')
519 			break;
520 		ram = simple_strtoul(hw, &hw, 0);
521 
522 		if (*hw++ != ',')
523 			break;
524 		while(1) {
525 			if (*hw == '0' && !valid[0])
526 				valid[0] = 1; /* Port 0 enabled */
527 			else if (*hw == '1' && !valid[1])
528 				valid[1] = 1; /* Port 1 enabled */
529 			else
530 				break;
531 			hw++;
532 		}
533 
534 		if (!valid[0] && !valid[1])
535 			break;	/* at least one port must be used */
536 
537 		if (*hw == ':' || *hw == '\x0')
538 			n2_run(io, irq, ram, valid[0], valid[1]);
539 
540 		if (*hw == '\x0')
541 			return first_card ? 0 : -EINVAL;
542 	}while(*hw++ == ':');
543 
544 	printk(KERN_ERR "n2: invalid hardware parameters\n");
545 	return first_card ? 0 : -EINVAL;
546 }
547 
548 
549 static void __exit n2_cleanup(void)
550 {
551 	card_t *card = first_card;
552 
553 	while (card) {
554 		card_t *ptr = card;
555 		card = card->next_card;
556 		n2_destroy_card(ptr);
557 	}
558 }
559 
560 
561 module_init(n2_init);
562 module_exit(n2_cleanup);
563 
564 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
565 MODULE_DESCRIPTION("RISCom/N2 serial port driver");
566 MODULE_LICENSE("GPL v2");
567 module_param(hw, charp, 0444);
568 MODULE_PARM_DESC(hw, "io,irq,ram,ports:io,irq,...");
569