xref: /openbmc/linux/drivers/net/wan/c101.c (revision 92ed1a76)
1 /*
2  * Moxa C101 synchronous serial card driver for Linux
3  *
4  * Copyright (C) 2000-2003 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  * Sources of information:
13  *    Hitachi HD64570 SCA User's Manual
14  *    Moxa C101 User's Manual
15  */
16 
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/capability.h>
20 #include <linux/slab.h>
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/errno.h>
24 #include <linux/init.h>
25 #include <linux/moduleparam.h>
26 #include <linux/netdevice.h>
27 #include <linux/hdlc.h>
28 #include <linux/delay.h>
29 #include <asm/io.h>
30 
31 #include "hd64570.h"
32 
33 
34 static const char* version = "Moxa C101 driver version: 1.15";
35 static const char* devname = "C101";
36 
37 #undef DEBUG_PKT
38 #define DEBUG_RINGS
39 
40 #define C101_PAGE 0x1D00
41 #define C101_DTR 0x1E00
42 #define C101_SCA 0x1F00
43 #define C101_WINDOW_SIZE 0x2000
44 #define C101_MAPPED_RAM_SIZE 0x4000
45 
46 #define RAM_SIZE (256 * 1024)
47 #define TX_RING_BUFFERS 10
48 #define RX_RING_BUFFERS ((RAM_SIZE - C101_WINDOW_SIZE) /		\
49 			 (sizeof(pkt_desc) + HDLC_MAX_MRU) - TX_RING_BUFFERS)
50 
51 #define CLOCK_BASE 9830400	/* 9.8304 MHz */
52 #define PAGE0_ALWAYS_MAPPED
53 
54 static char *hw;		/* pointer to hw=xxx command line string */
55 
56 
57 typedef struct card_s {
58 	struct net_device *dev;
59 	spinlock_t lock;	/* TX lock */
60 	u8 __iomem *win0base;	/* ISA window base address */
61 	u32 phy_winbase;	/* ISA physical base address */
62 	sync_serial_settings settings;
63 	int rxpart;		/* partial frame received, next frame invalid*/
64 	unsigned short encoding;
65 	unsigned short parity;
66 	u16 rx_ring_buffers;	/* number of buffers in a ring */
67 	u16 tx_ring_buffers;
68 	u16 buff_offset;	/* offset of first buffer of first channel */
69 	u16 rxin;		/* rx ring buffer 'in' pointer */
70 	u16 txin;		/* tx ring buffer 'in' and 'last' pointers */
71 	u16 txlast;
72 	u8 rxs, txs, tmc;	/* SCA registers */
73 	u8 irq;			/* IRQ (3-15) */
74 	u8 page;
75 
76 	struct card_s *next_card;
77 }card_t;
78 
79 typedef card_t port_t;
80 
81 static card_t *first_card;
82 static card_t **new_card = &first_card;
83 
84 
85 #define sca_in(reg, card)	   readb((card)->win0base + C101_SCA + (reg))
86 #define sca_out(value, reg, card)  writeb(value, (card)->win0base + C101_SCA + (reg))
87 #define sca_inw(reg, card)	   readw((card)->win0base + C101_SCA + (reg))
88 
89 /* EDA address register must be set in EDAL, EDAH order - 8 bit ISA bus */
90 #define sca_outw(value, reg, card) do { \
91 	writeb(value & 0xFF, (card)->win0base + C101_SCA + (reg)); \
92 	writeb((value >> 8 ) & 0xFF, (card)->win0base + C101_SCA + (reg + 1));\
93 } while(0)
94 
95 #define port_to_card(port)	   (port)
96 #define log_node(port)		   (0)
97 #define phy_node(port)		   (0)
98 #define winsize(card)		   (C101_WINDOW_SIZE)
99 #define win0base(card)		   ((card)->win0base)
100 #define winbase(card)      	   ((card)->win0base + 0x2000)
101 #define get_port(card, port)	   (card)
102 static void sca_msci_intr(port_t *port);
103 
104 
105 static inline u8 sca_get_page(card_t *card)
106 {
107 	return card->page;
108 }
109 
110 static inline void openwin(card_t *card, u8 page)
111 {
112 	card->page = page;
113 	writeb(page, card->win0base + C101_PAGE);
114 }
115 
116 
117 #include "hd64570.c"
118 
119 
120 static inline void set_carrier(port_t *port)
121 {
122 	if (!(sca_in(MSCI1_OFFSET + ST3, port) & ST3_DCD))
123 		netif_carrier_on(port_to_dev(port));
124 	else
125 		netif_carrier_off(port_to_dev(port));
126 }
127 
128 
129 static void sca_msci_intr(port_t *port)
130 {
131 	u8 stat = sca_in(MSCI0_OFFSET + ST1, port); /* read MSCI ST1 status */
132 
133 	/* Reset MSCI TX underrun and CDCD (ignored) status bit */
134 	sca_out(stat & (ST1_UDRN | ST1_CDCD), MSCI0_OFFSET + ST1, port);
135 
136 	if (stat & ST1_UDRN) {
137 		/* TX Underrun error detected */
138 		port_to_dev(port)->stats.tx_errors++;
139 		port_to_dev(port)->stats.tx_fifo_errors++;
140 	}
141 
142 	stat = sca_in(MSCI1_OFFSET + ST1, port); /* read MSCI1 ST1 status */
143 	/* Reset MSCI CDCD status bit - uses ch#2 DCD input */
144 	sca_out(stat & ST1_CDCD, MSCI1_OFFSET + ST1, port);
145 
146 	if (stat & ST1_CDCD)
147 		set_carrier(port);
148 }
149 
150 
151 static void c101_set_iface(port_t *port)
152 {
153 	u8 rxs = port->rxs & CLK_BRG_MASK;
154 	u8 txs = port->txs & CLK_BRG_MASK;
155 
156 	switch(port->settings.clock_type) {
157 	case CLOCK_INT:
158 		rxs |= CLK_BRG_RX; /* TX clock */
159 		txs |= CLK_RXCLK_TX; /* BRG output */
160 		break;
161 
162 	case CLOCK_TXINT:
163 		rxs |= CLK_LINE_RX; /* RXC input */
164 		txs |= CLK_BRG_TX; /* BRG output */
165 		break;
166 
167 	case CLOCK_TXFROMRX:
168 		rxs |= CLK_LINE_RX; /* RXC input */
169 		txs |= CLK_RXCLK_TX; /* RX clock */
170 		break;
171 
172 	default:	/* EXTernal clock */
173 		rxs |= CLK_LINE_RX; /* RXC input */
174 		txs |= CLK_LINE_TX; /* TXC input */
175 	}
176 
177 	port->rxs = rxs;
178 	port->txs = txs;
179 	sca_out(rxs, MSCI1_OFFSET + RXS, port);
180 	sca_out(txs, MSCI1_OFFSET + TXS, port);
181 	sca_set_port(port);
182 }
183 
184 
185 static int c101_open(struct net_device *dev)
186 {
187 	port_t *port = dev_to_port(dev);
188 	int result;
189 
190 	result = hdlc_open(dev);
191 	if (result)
192 		return result;
193 
194 	writeb(1, port->win0base + C101_DTR);
195 	sca_out(0, MSCI1_OFFSET + CTL, port); /* RTS uses ch#2 output */
196 	sca_open(dev);
197 	/* DCD is connected to port 2 !@#$%^& - disable MSCI0 CDCD interrupt */
198 	sca_out(IE1_UDRN, MSCI0_OFFSET + IE1, port);
199 	sca_out(IE0_TXINT, MSCI0_OFFSET + IE0, port);
200 
201 	set_carrier(port);
202 
203 	/* enable MSCI1 CDCD interrupt */
204 	sca_out(IE1_CDCD, MSCI1_OFFSET + IE1, port);
205 	sca_out(IE0_RXINTA, MSCI1_OFFSET + IE0, port);
206 	sca_out(0x48, IER0, port); /* TXINT #0 and RXINT #1 */
207 	c101_set_iface(port);
208 	return 0;
209 }
210 
211 
212 static int c101_close(struct net_device *dev)
213 {
214 	port_t *port = dev_to_port(dev);
215 
216 	sca_close(dev);
217 	writeb(0, port->win0base + C101_DTR);
218 	sca_out(CTL_NORTS, MSCI1_OFFSET + CTL, port);
219 	hdlc_close(dev);
220 	return 0;
221 }
222 
223 
224 static int c101_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
225 {
226 	const size_t size = sizeof(sync_serial_settings);
227 	sync_serial_settings new_line;
228 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
229 	port_t *port = dev_to_port(dev);
230 
231 #ifdef DEBUG_RINGS
232 	if (cmd == SIOCDEVPRIVATE) {
233 		sca_dump_rings(dev);
234 		printk(KERN_DEBUG "MSCI1: ST: %02x %02x %02x %02x\n",
235 		       sca_in(MSCI1_OFFSET + ST0, port),
236 		       sca_in(MSCI1_OFFSET + ST1, port),
237 		       sca_in(MSCI1_OFFSET + ST2, port),
238 		       sca_in(MSCI1_OFFSET + ST3, port));
239 		return 0;
240 	}
241 #endif
242 	if (cmd != SIOCWANDEV)
243 		return hdlc_ioctl(dev, ifr, cmd);
244 
245 	switch(ifr->ifr_settings.type) {
246 	case IF_GET_IFACE:
247 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
248 		if (ifr->ifr_settings.size < size) {
249 			ifr->ifr_settings.size = size; /* data size wanted */
250 			return -ENOBUFS;
251 		}
252 		if (copy_to_user(line, &port->settings, size))
253 			return -EFAULT;
254 		return 0;
255 
256 	case IF_IFACE_SYNC_SERIAL:
257 		if(!capable(CAP_NET_ADMIN))
258 			return -EPERM;
259 
260 		if (copy_from_user(&new_line, line, size))
261 			return -EFAULT;
262 
263 		if (new_line.clock_type != CLOCK_EXT &&
264 		    new_line.clock_type != CLOCK_TXFROMRX &&
265 		    new_line.clock_type != CLOCK_INT &&
266 		    new_line.clock_type != CLOCK_TXINT)
267 			return -EINVAL;	/* No such clock setting */
268 
269 		if (new_line.loopback != 0 && new_line.loopback != 1)
270 			return -EINVAL;
271 
272 		memcpy(&port->settings, &new_line, size); /* Update settings */
273 		c101_set_iface(port);
274 		return 0;
275 
276 	default:
277 		return hdlc_ioctl(dev, ifr, cmd);
278 	}
279 }
280 
281 
282 
283 static void c101_destroy_card(card_t *card)
284 {
285 	readb(card->win0base + C101_PAGE); /* Resets SCA? */
286 
287 	if (card->irq)
288 		free_irq(card->irq, card);
289 
290 	if (card->win0base) {
291 		iounmap(card->win0base);
292 		release_mem_region(card->phy_winbase, C101_MAPPED_RAM_SIZE);
293 	}
294 
295 	free_netdev(card->dev);
296 
297 	kfree(card);
298 }
299 
300 static const struct net_device_ops c101_ops = {
301 	.ndo_open       = c101_open,
302 	.ndo_stop       = c101_close,
303 	.ndo_change_mtu = hdlc_change_mtu,
304 	.ndo_start_xmit = hdlc_start_xmit,
305 	.ndo_do_ioctl   = c101_ioctl,
306 };
307 
308 static int __init c101_run(unsigned long irq, unsigned long winbase)
309 {
310 	struct net_device *dev;
311 	hdlc_device *hdlc;
312 	card_t *card;
313 	int result;
314 
315 	if (irq<3 || irq>15 || irq == 6) /* FIXME */ {
316 		printk(KERN_ERR "c101: invalid IRQ value\n");
317 		return -ENODEV;
318 	}
319 
320 	if (winbase < 0xC0000 || winbase > 0xDFFFF || (winbase & 0x3FFF) !=0) {
321 		printk(KERN_ERR "c101: invalid RAM value\n");
322 		return -ENODEV;
323 	}
324 
325 	card = kzalloc(sizeof(card_t), GFP_KERNEL);
326 	if (card == NULL) {
327 		printk(KERN_ERR "c101: unable to allocate memory\n");
328 		return -ENOBUFS;
329 	}
330 
331 	card->dev = alloc_hdlcdev(card);
332 	if (!card->dev) {
333 		printk(KERN_ERR "c101: unable to allocate memory\n");
334 		kfree(card);
335 		return -ENOBUFS;
336 	}
337 
338 	if (request_irq(irq, sca_intr, 0, devname, card)) {
339 		printk(KERN_ERR "c101: could not allocate IRQ\n");
340 		c101_destroy_card(card);
341 		return -EBUSY;
342 	}
343 	card->irq = irq;
344 
345 	if (!request_mem_region(winbase, C101_MAPPED_RAM_SIZE, devname)) {
346 		printk(KERN_ERR "c101: could not request RAM window\n");
347 		c101_destroy_card(card);
348 		return -EBUSY;
349 	}
350 	card->phy_winbase = winbase;
351 	card->win0base = ioremap(winbase, C101_MAPPED_RAM_SIZE);
352 	if (!card->win0base) {
353 		printk(KERN_ERR "c101: could not map I/O address\n");
354 		c101_destroy_card(card);
355 		return -EFAULT;
356 	}
357 
358 	card->tx_ring_buffers = TX_RING_BUFFERS;
359 	card->rx_ring_buffers = RX_RING_BUFFERS;
360 	card->buff_offset = C101_WINDOW_SIZE; /* Bytes 1D00-1FFF reserved */
361 
362 	readb(card->win0base + C101_PAGE); /* Resets SCA? */
363 	udelay(100);
364 	writeb(0, card->win0base + C101_PAGE);
365 	writeb(0, card->win0base + C101_DTR); /* Power-up for RAM? */
366 
367 	sca_init(card, 0);
368 
369 	dev = port_to_dev(card);
370 	hdlc = dev_to_hdlc(dev);
371 
372 	spin_lock_init(&card->lock);
373 	dev->irq = irq;
374 	dev->mem_start = winbase;
375 	dev->mem_end = winbase + C101_MAPPED_RAM_SIZE - 1;
376 	dev->tx_queue_len = 50;
377 	dev->netdev_ops = &c101_ops;
378 	hdlc->attach = sca_attach;
379 	hdlc->xmit = sca_xmit;
380 	card->settings.clock_type = CLOCK_EXT;
381 
382 	result = register_hdlc_device(dev);
383 	if (result) {
384 		printk(KERN_WARNING "c101: unable to register hdlc device\n");
385 		c101_destroy_card(card);
386 		return result;
387 	}
388 
389 	sca_init_port(card); /* Set up C101 memory */
390 	set_carrier(card);
391 
392 	printk(KERN_INFO "%s: Moxa C101 on IRQ%u,"
393 	       " using %u TX + %u RX packets rings\n",
394 	       dev->name, card->irq,
395 	       card->tx_ring_buffers, card->rx_ring_buffers);
396 
397 	*new_card = card;
398 	new_card = &card->next_card;
399 	return 0;
400 }
401 
402 
403 
404 static int __init c101_init(void)
405 {
406 	if (hw == NULL) {
407 #ifdef MODULE
408 		printk(KERN_INFO "c101: no card initialized\n");
409 #endif
410 		return -EINVAL;	/* no parameters specified, abort */
411 	}
412 
413 	printk(KERN_INFO "%s\n", version);
414 
415 	do {
416 		unsigned long irq, ram;
417 
418 		irq = simple_strtoul(hw, &hw, 0);
419 
420 		if (*hw++ != ',')
421 			break;
422 		ram = simple_strtoul(hw, &hw, 0);
423 
424 		if (*hw == ':' || *hw == '\x0')
425 			c101_run(irq, ram);
426 
427 		if (*hw == '\x0')
428 			return first_card ? 0 : -EINVAL;
429 	}while(*hw++ == ':');
430 
431 	printk(KERN_ERR "c101: invalid hardware parameters\n");
432 	return first_card ? 0 : -EINVAL;
433 }
434 
435 
436 static void __exit c101_cleanup(void)
437 {
438 	card_t *card = first_card;
439 
440 	while (card) {
441 		card_t *ptr = card;
442 		card = card->next_card;
443 		unregister_hdlc_device(port_to_dev(ptr));
444 		c101_destroy_card(ptr);
445 	}
446 }
447 
448 
449 module_init(c101_init);
450 module_exit(c101_cleanup);
451 
452 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
453 MODULE_DESCRIPTION("Moxa C101 serial port driver");
454 MODULE_LICENSE("GPL v2");
455 module_param(hw, charp, 0444);
456 MODULE_PARM_DESC(hw, "irq,ram:irq,...");
457