xref: /openbmc/linux/drivers/net/wan/n2.c (revision 367b8112)
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/slab.h>
22 #include <linux/types.h>
23 #include <linux/fcntl.h>
24 #include <linux/in.h>
25 #include <linux/string.h>
26 #include <linux/errno.h>
27 #include <linux/init.h>
28 #include <linux/ioport.h>
29 #include <linux/moduleparam.h>
30 #include <linux/netdevice.h>
31 #include <linux/hdlc.h>
32 #include <asm/io.h>
33 #include "hd64570.h"
34 
35 
36 static const char* version = "SDL RISCom/N2 driver version: 1.15";
37 static const char* devname = "RISCom/N2";
38 
39 #undef DEBUG_PKT
40 #define DEBUG_RINGS
41 
42 #define USE_WINDOWSIZE 16384
43 #define USE_BUS16BITS 1
44 #define CLOCK_BASE 9830400	/* 9.8304 MHz */
45 #define MAX_PAGES      16	/* 16 RAM pages at max */
46 #define MAX_RAM_SIZE 0x80000	/* 512 KB */
47 #if MAX_RAM_SIZE > MAX_PAGES * USE_WINDOWSIZE
48 #undef MAX_RAM_SIZE
49 #define MAX_RAM_SIZE (MAX_PAGES * USE_WINDOWSIZE)
50 #endif
51 #define N2_IOPORTS 0x10
52 #define NEED_DETECT_RAM
53 #define NEED_SCA_MSCI_INTR
54 #define MAX_TX_BUFFERS 10
55 
56 static char *hw = NULL;	/* pointer to hw=xxx command line string */
57 
58 /* RISCom/N2 Board Registers */
59 
60 /* PC Control Register */
61 #define N2_PCR 0
62 #define PCR_RUNSCA 1     /* Run 64570 */
63 #define PCR_VPM    2     /* Enable VPM - needed if using RAM above 1 MB */
64 #define PCR_ENWIN  4     /* Open window */
65 #define PCR_BUS16  8     /* 16-bit bus */
66 
67 
68 /* Memory Base Address Register */
69 #define N2_BAR 2
70 
71 
72 /* Page Scan Register  */
73 #define N2_PSR 4
74 #define WIN16K       0x00
75 #define WIN32K       0x20
76 #define WIN64K       0x40
77 #define PSR_WINBITS  0x60
78 #define PSR_DMAEN    0x80
79 #define PSR_PAGEBITS 0x0F
80 
81 
82 /* Modem Control Reg */
83 #define N2_MCR 6
84 #define CLOCK_OUT_PORT1 0x80
85 #define CLOCK_OUT_PORT0 0x40
86 #define TX422_PORT1     0x20
87 #define TX422_PORT0     0x10
88 #define DSR_PORT1       0x08
89 #define DSR_PORT0       0x04
90 #define DTR_PORT1       0x02
91 #define DTR_PORT0       0x01
92 
93 
94 typedef struct port_s {
95 	struct net_device *dev;
96 	struct card_s *card;
97 	spinlock_t lock;	/* TX lock */
98 	sync_serial_settings settings;
99 	int valid;		/* port enabled */
100 	int rxpart;		/* partial frame received, next frame invalid*/
101 	unsigned short encoding;
102 	unsigned short parity;
103 	u16 rxin;		/* rx ring buffer 'in' pointer */
104 	u16 txin;		/* tx ring buffer 'in' and 'last' pointers */
105 	u16 txlast;
106 	u8 rxs, txs, tmc;	/* SCA registers */
107 	u8 phy_node;		/* physical port # - 0 or 1 */
108 	u8 log_node;		/* logical port # */
109 }port_t;
110 
111 
112 
113 typedef struct card_s {
114 	u8 __iomem *winbase;		/* ISA window base address */
115 	u32 phy_winbase;	/* ISA physical base address */
116 	u32 ram_size;		/* number of bytes */
117 	u16 io;			/* IO Base address */
118 	u16 buff_offset;	/* offset of first buffer of first channel */
119 	u16 rx_ring_buffers;	/* number of buffers in a ring */
120 	u16 tx_ring_buffers;
121 	u8 irq;			/* IRQ (3-15) */
122 
123 	port_t ports[2];
124 	struct card_s *next_card;
125 }card_t;
126 
127 
128 static card_t *first_card;
129 static card_t **new_card = &first_card;
130 
131 
132 #define sca_reg(reg, card) (0x8000 | (card)->io | \
133 			    ((reg) & 0x0F) | (((reg) & 0xF0) << 6))
134 #define sca_in(reg, card)		inb(sca_reg(reg, card))
135 #define sca_out(value, reg, card)	outb(value, sca_reg(reg, card))
136 #define sca_inw(reg, card)		inw(sca_reg(reg, card))
137 #define sca_outw(value, reg, card)	outw(value, sca_reg(reg, card))
138 
139 #define port_to_card(port)		((port)->card)
140 #define log_node(port)			((port)->log_node)
141 #define phy_node(port)			((port)->phy_node)
142 #define winsize(card)			(USE_WINDOWSIZE)
143 #define winbase(card)      	     	((card)->winbase)
144 #define get_port(card, port)		((card)->ports[port].valid ? \
145 					 &(card)->ports[port] : NULL)
146 
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 
163 #include "hd6457x.c"
164 
165 
166 
167 static void n2_set_iface(port_t *port)
168 {
169 	card_t *card = port->card;
170 	int io = card->io;
171 	u8 mcr = inb(io + N2_MCR);
172 	u8 msci = get_msci(port);
173 	u8 rxs = port->rxs & CLK_BRG_MASK;
174 	u8 txs = port->txs & CLK_BRG_MASK;
175 
176 	switch(port->settings.clock_type) {
177 	case CLOCK_INT:
178 		mcr |= port->phy_node ? CLOCK_OUT_PORT1 : CLOCK_OUT_PORT0;
179 		rxs |= CLK_BRG_RX; /* BRG output */
180 		txs |= CLK_RXCLK_TX; /* RX clock */
181 		break;
182 
183 	case CLOCK_TXINT:
184 		mcr |= port->phy_node ? CLOCK_OUT_PORT1 : CLOCK_OUT_PORT0;
185 		rxs |= CLK_LINE_RX; /* RXC input */
186 		txs |= CLK_BRG_TX; /* BRG output */
187 		break;
188 
189 	case CLOCK_TXFROMRX:
190 		mcr |= port->phy_node ? CLOCK_OUT_PORT1 : CLOCK_OUT_PORT0;
191 		rxs |= CLK_LINE_RX; /* RXC input */
192 		txs |= CLK_RXCLK_TX; /* RX clock */
193 		break;
194 
195 	default:		/* Clock EXTernal */
196 		mcr &= port->phy_node ? ~CLOCK_OUT_PORT1 : ~CLOCK_OUT_PORT0;
197 		rxs |= CLK_LINE_RX; /* RXC input */
198 		txs |= CLK_LINE_TX; /* TXC input */
199 	}
200 
201 	outb(mcr, io + N2_MCR);
202 	port->rxs = rxs;
203 	port->txs = txs;
204 	sca_out(rxs, msci + RXS, card);
205 	sca_out(txs, msci + TXS, card);
206 	sca_set_port(port);
207 }
208 
209 
210 
211 static int n2_open(struct net_device *dev)
212 {
213 	port_t *port = dev_to_port(dev);
214 	int io = port->card->io;
215 	u8 mcr = inb(io + N2_MCR) | (port->phy_node ? TX422_PORT1:TX422_PORT0);
216 	int result;
217 
218 	result = hdlc_open(dev);
219 	if (result)
220 		return result;
221 
222 	mcr &= port->phy_node ? ~DTR_PORT1 : ~DTR_PORT0; /* set DTR ON */
223 	outb(mcr, io + N2_MCR);
224 
225 	outb(inb(io + N2_PCR) | PCR_ENWIN, io + N2_PCR); /* open window */
226 	outb(inb(io + N2_PSR) | PSR_DMAEN, io + N2_PSR); /* enable dma */
227 	sca_open(dev);
228 	n2_set_iface(port);
229 	return 0;
230 }
231 
232 
233 
234 static int n2_close(struct net_device *dev)
235 {
236 	port_t *port = dev_to_port(dev);
237 	int io = port->card->io;
238 	u8 mcr = inb(io+N2_MCR) | (port->phy_node ? TX422_PORT1 : TX422_PORT0);
239 
240 	sca_close(dev);
241 	mcr |= port->phy_node ? DTR_PORT1 : DTR_PORT0; /* set DTR OFF */
242 	outb(mcr, io + N2_MCR);
243 	hdlc_close(dev);
244 	return 0;
245 }
246 
247 
248 
249 static int n2_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
250 {
251 	const size_t size = sizeof(sync_serial_settings);
252 	sync_serial_settings new_line;
253 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
254 	port_t *port = dev_to_port(dev);
255 
256 #ifdef DEBUG_RINGS
257 	if (cmd == SIOCDEVPRIVATE) {
258 		sca_dump_rings(dev);
259 		return 0;
260 	}
261 #endif
262 	if (cmd != SIOCWANDEV)
263 		return hdlc_ioctl(dev, ifr, cmd);
264 
265 	switch(ifr->ifr_settings.type) {
266 	case IF_GET_IFACE:
267 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
268 		if (ifr->ifr_settings.size < size) {
269 			ifr->ifr_settings.size = size; /* data size wanted */
270 			return -ENOBUFS;
271 		}
272 		if (copy_to_user(line, &port->settings, size))
273 			return -EFAULT;
274 		return 0;
275 
276 	case IF_IFACE_SYNC_SERIAL:
277 		if(!capable(CAP_NET_ADMIN))
278 			return -EPERM;
279 
280 		if (copy_from_user(&new_line, line, size))
281 			return -EFAULT;
282 
283 		if (new_line.clock_type != CLOCK_EXT &&
284 		    new_line.clock_type != CLOCK_TXFROMRX &&
285 		    new_line.clock_type != CLOCK_INT &&
286 		    new_line.clock_type != CLOCK_TXINT)
287 		return -EINVAL;	/* No such clock setting */
288 
289 		if (new_line.loopback != 0 && new_line.loopback != 1)
290 			return -EINVAL;
291 
292 		memcpy(&port->settings, &new_line, size); /* Update settings */
293 		n2_set_iface(port);
294 		return 0;
295 
296 	default:
297 		return hdlc_ioctl(dev, ifr, cmd);
298 	}
299 }
300 
301 
302 
303 static void n2_destroy_card(card_t *card)
304 {
305 	int cnt;
306 
307 	for (cnt = 0; cnt < 2; cnt++)
308 		if (card->ports[cnt].card) {
309 			struct net_device *dev = port_to_dev(&card->ports[cnt]);
310 			unregister_hdlc_device(dev);
311 		}
312 
313 	if (card->irq)
314 		free_irq(card->irq, card);
315 
316 	if (card->winbase) {
317 		iounmap(card->winbase);
318 		release_mem_region(card->phy_winbase, USE_WINDOWSIZE);
319 	}
320 
321 	if (card->io)
322 		release_region(card->io, N2_IOPORTS);
323 	if (card->ports[0].dev)
324 		free_netdev(card->ports[0].dev);
325 	if (card->ports[1].dev)
326 		free_netdev(card->ports[1].dev);
327 	kfree(card);
328 }
329 
330 
331 
332 static int __init n2_run(unsigned long io, unsigned long irq,
333 			 unsigned long winbase, long valid0, long valid1)
334 {
335 	card_t *card;
336 	u8 cnt, pcr;
337 	int i;
338 
339 	if (io < 0x200 || io > 0x3FF || (io % N2_IOPORTS) != 0) {
340 		printk(KERN_ERR "n2: invalid I/O port value\n");
341 		return -ENODEV;
342 	}
343 
344 	if (irq < 3 || irq > 15 || irq == 6) /* FIXME */ {
345 		printk(KERN_ERR "n2: invalid IRQ value\n");
346 		return -ENODEV;
347 	}
348 
349 	if (winbase < 0xA0000 || winbase > 0xFFFFF || (winbase & 0xFFF) != 0) {
350 		printk(KERN_ERR "n2: invalid RAM value\n");
351 		return -ENODEV;
352 	}
353 
354 	card = kzalloc(sizeof(card_t), GFP_KERNEL);
355 	if (card == NULL) {
356 		printk(KERN_ERR "n2: unable to allocate memory\n");
357 		return -ENOBUFS;
358 	}
359 
360 	card->ports[0].dev = alloc_hdlcdev(&card->ports[0]);
361 	card->ports[1].dev = alloc_hdlcdev(&card->ports[1]);
362 	if (!card->ports[0].dev || !card->ports[1].dev) {
363 		printk(KERN_ERR "n2: unable to allocate memory\n");
364 		n2_destroy_card(card);
365 		return -ENOMEM;
366 	}
367 
368 	if (!request_region(io, N2_IOPORTS, devname)) {
369 		printk(KERN_ERR "n2: I/O port region in use\n");
370 		n2_destroy_card(card);
371 		return -EBUSY;
372 	}
373 	card->io = io;
374 
375 	if (request_irq(irq, &sca_intr, 0, devname, card)) {
376 		printk(KERN_ERR "n2: could not allocate IRQ\n");
377 		n2_destroy_card(card);
378 		return(-EBUSY);
379 	}
380 	card->irq = irq;
381 
382 	if (!request_mem_region(winbase, USE_WINDOWSIZE, devname)) {
383 		printk(KERN_ERR "n2: could not request RAM window\n");
384 		n2_destroy_card(card);
385 		return(-EBUSY);
386 	}
387 	card->phy_winbase = winbase;
388 	card->winbase = ioremap(winbase, USE_WINDOWSIZE);
389 	if (!card->winbase) {
390 		printk(KERN_ERR "n2: ioremap() failed\n");
391 		n2_destroy_card(card);
392 		return -EFAULT;
393 	}
394 
395 	outb(0, io + N2_PCR);
396 	outb(winbase >> 12, io + N2_BAR);
397 
398 	switch (USE_WINDOWSIZE) {
399 	case 16384:
400 		outb(WIN16K, io + N2_PSR);
401 		break;
402 
403 	case 32768:
404 		outb(WIN32K, io + N2_PSR);
405 		break;
406 
407 	case 65536:
408 		outb(WIN64K, io + N2_PSR);
409 		break;
410 
411 	default:
412 		printk(KERN_ERR "n2: invalid window size\n");
413 		n2_destroy_card(card);
414 		return -ENODEV;
415 	}
416 
417 	pcr = PCR_ENWIN | PCR_VPM | (USE_BUS16BITS ? PCR_BUS16 : 0);
418 	outb(pcr, io + N2_PCR);
419 
420 	card->ram_size = sca_detect_ram(card, card->winbase, MAX_RAM_SIZE);
421 
422 	/* number of TX + RX buffers for one port */
423 	i = card->ram_size / ((valid0 + valid1) * (sizeof(pkt_desc) +
424 						   HDLC_MAX_MRU));
425 
426 	card->tx_ring_buffers = min(i / 2, MAX_TX_BUFFERS);
427 	card->rx_ring_buffers = i - card->tx_ring_buffers;
428 
429 	card->buff_offset = (valid0 + valid1) * sizeof(pkt_desc) *
430 		(card->tx_ring_buffers + card->rx_ring_buffers);
431 
432 	printk(KERN_INFO "n2: RISCom/N2 %u KB RAM, IRQ%u, "
433 	       "using %u TX + %u RX packets rings\n", card->ram_size / 1024,
434 	       card->irq, card->tx_ring_buffers, card->rx_ring_buffers);
435 
436 	if (card->tx_ring_buffers < 1) {
437 		printk(KERN_ERR "n2: RAM test failed\n");
438 		n2_destroy_card(card);
439 		return -EIO;
440 	}
441 
442 	pcr |= PCR_RUNSCA;		/* run SCA */
443 	outb(pcr, io + N2_PCR);
444 	outb(0, io + N2_MCR);
445 
446 	sca_init(card, 0);
447 	for (cnt = 0; cnt < 2; cnt++) {
448 		port_t *port = &card->ports[cnt];
449 		struct net_device *dev = port_to_dev(port);
450 		hdlc_device *hdlc = dev_to_hdlc(dev);
451 
452 		if ((cnt == 0 && !valid0) || (cnt == 1 && !valid1))
453 			continue;
454 
455 		port->phy_node = cnt;
456 		port->valid = 1;
457 
458 		if ((cnt == 1) && valid0)
459 			port->log_node = 1;
460 
461 		spin_lock_init(&port->lock);
462 		dev->irq = irq;
463 		dev->mem_start = winbase;
464 		dev->mem_end = winbase + USE_WINDOWSIZE - 1;
465 		dev->tx_queue_len = 50;
466 		dev->do_ioctl = n2_ioctl;
467 		dev->open = n2_open;
468 		dev->stop = n2_close;
469 		hdlc->attach = sca_attach;
470 		hdlc->xmit = sca_xmit;
471 		port->settings.clock_type = CLOCK_EXT;
472 		port->card = card;
473 
474 		if (register_hdlc_device(dev)) {
475 			printk(KERN_WARNING "n2: unable to register hdlc "
476 			       "device\n");
477 			port->card = NULL;
478 			n2_destroy_card(card);
479 			return -ENOBUFS;
480 		}
481 		sca_init_sync_port(port); /* Set up SCA memory */
482 
483 		printk(KERN_INFO "%s: RISCom/N2 node %d\n",
484 		       dev->name, port->phy_node);
485 	}
486 
487 	*new_card = card;
488 	new_card = &card->next_card;
489 
490 	return 0;
491 }
492 
493 
494 
495 static int __init n2_init(void)
496 {
497 	if (hw==NULL) {
498 #ifdef MODULE
499 		printk(KERN_INFO "n2: no card initialized\n");
500 #endif
501 		return -EINVAL;	/* no parameters specified, abort */
502 	}
503 
504 	printk(KERN_INFO "%s\n", version);
505 
506 	do {
507 		unsigned long io, irq, ram;
508 		long valid[2] = { 0, 0 }; /* Default = both ports disabled */
509 
510 		io = simple_strtoul(hw, &hw, 0);
511 
512 		if (*hw++ != ',')
513 			break;
514 		irq = simple_strtoul(hw, &hw, 0);
515 
516 		if (*hw++ != ',')
517 			break;
518 		ram = simple_strtoul(hw, &hw, 0);
519 
520 		if (*hw++ != ',')
521 			break;
522 		while(1) {
523 			if (*hw == '0' && !valid[0])
524 				valid[0] = 1; /* Port 0 enabled */
525 			else if (*hw == '1' && !valid[1])
526 				valid[1] = 1; /* Port 1 enabled */
527 			else
528 				break;
529 			hw++;
530 		}
531 
532 		if (!valid[0] && !valid[1])
533 			break;	/* at least one port must be used */
534 
535 		if (*hw == ':' || *hw == '\x0')
536 			n2_run(io, irq, ram, valid[0], valid[1]);
537 
538 		if (*hw == '\x0')
539 			return first_card ? 0 : -EINVAL;
540 	}while(*hw++ == ':');
541 
542 	printk(KERN_ERR "n2: invalid hardware parameters\n");
543 	return first_card ? 0 : -EINVAL;
544 }
545 
546 
547 static void __exit n2_cleanup(void)
548 {
549 	card_t *card = first_card;
550 
551 	while (card) {
552 		card_t *ptr = card;
553 		card = card->next_card;
554 		n2_destroy_card(ptr);
555 	}
556 }
557 
558 
559 module_init(n2_init);
560 module_exit(n2_cleanup);
561 
562 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
563 MODULE_DESCRIPTION("RISCom/N2 serial port driver");
564 MODULE_LICENSE("GPL v2");
565 module_param(hw, charp, 0444);
566 MODULE_PARM_DESC(hw, "io,irq,ram,ports:io,irq,...");
567