xref: /openbmc/linux/drivers/net/wan/c101.c (revision b627b4ed)
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/slab.h>
20 #include <linux/types.h>
21 #include <linux/string.h>
22 #include <linux/errno.h>
23 #include <linux/init.h>
24 #include <linux/moduleparam.h>
25 #include <linux/netdevice.h>
26 #include <linux/hdlc.h>
27 #include <linux/delay.h>
28 #include <asm/io.h>
29 
30 #include "hd64570.h"
31 
32 
33 static const char* version = "Moxa C101 driver version: 1.15";
34 static const char* devname = "C101";
35 
36 #undef DEBUG_PKT
37 #define DEBUG_RINGS
38 
39 #define C101_PAGE 0x1D00
40 #define C101_DTR 0x1E00
41 #define C101_SCA 0x1F00
42 #define C101_WINDOW_SIZE 0x2000
43 #define C101_MAPPED_RAM_SIZE 0x4000
44 
45 #define RAM_SIZE (256 * 1024)
46 #define TX_RING_BUFFERS 10
47 #define RX_RING_BUFFERS ((RAM_SIZE - C101_WINDOW_SIZE) /		\
48 			 (sizeof(pkt_desc) + HDLC_MAX_MRU) - TX_RING_BUFFERS)
49 
50 #define CLOCK_BASE 9830400	/* 9.8304 MHz */
51 #define PAGE0_ALWAYS_MAPPED
52 
53 static char *hw;		/* pointer to hw=xxx command line string */
54 
55 
56 typedef struct card_s {
57 	struct net_device *dev;
58 	spinlock_t lock;	/* TX lock */
59 	u8 __iomem *win0base;	/* ISA window base address */
60 	u32 phy_winbase;	/* ISA physical base address */
61 	sync_serial_settings settings;
62 	int rxpart;		/* partial frame received, next frame invalid*/
63 	unsigned short encoding;
64 	unsigned short parity;
65 	u16 rx_ring_buffers;	/* number of buffers in a ring */
66 	u16 tx_ring_buffers;
67 	u16 buff_offset;	/* offset of first buffer of first channel */
68 	u16 rxin;		/* rx ring buffer 'in' pointer */
69 	u16 txin;		/* tx ring buffer 'in' and 'last' pointers */
70 	u16 txlast;
71 	u8 rxs, txs, tmc;	/* SCA registers */
72 	u8 irq;			/* IRQ (3-15) */
73 	u8 page;
74 
75 	struct card_s *next_card;
76 }card_t;
77 
78 typedef card_t port_t;
79 
80 static card_t *first_card;
81 static card_t **new_card = &first_card;
82 
83 
84 #define sca_in(reg, card)	   readb((card)->win0base + C101_SCA + (reg))
85 #define sca_out(value, reg, card)  writeb(value, (card)->win0base + C101_SCA + (reg))
86 #define sca_inw(reg, card)	   readw((card)->win0base + C101_SCA + (reg))
87 
88 /* EDA address register must be set in EDAL, EDAH order - 8 bit ISA bus */
89 #define sca_outw(value, reg, card) do { \
90 	writeb(value & 0xFF, (card)->win0base + C101_SCA + (reg)); \
91 	writeb((value >> 8 ) & 0xFF, (card)->win0base + C101_SCA + (reg + 1));\
92 } while(0)
93 
94 #define port_to_card(port)	   (port)
95 #define log_node(port)		   (0)
96 #define phy_node(port)		   (0)
97 #define winsize(card)		   (C101_WINDOW_SIZE)
98 #define win0base(card)		   ((card)->win0base)
99 #define winbase(card)      	   ((card)->win0base + 0x2000)
100 #define get_port(card, port)	   (card)
101 static void sca_msci_intr(port_t *port);
102 
103 
104 static inline u8 sca_get_page(card_t *card)
105 {
106 	return card->page;
107 }
108 
109 static inline void openwin(card_t *card, u8 page)
110 {
111 	card->page = page;
112 	writeb(page, card->win0base + C101_PAGE);
113 }
114 
115 
116 #include "hd64570.c"
117 
118 
119 static inline void set_carrier(port_t *port)
120 {
121 	if (!(sca_in(MSCI1_OFFSET + ST3, port) & ST3_DCD))
122 		netif_carrier_on(port_to_dev(port));
123 	else
124 		netif_carrier_off(port_to_dev(port));
125 }
126 
127 
128 static void sca_msci_intr(port_t *port)
129 {
130 	u8 stat = sca_in(MSCI0_OFFSET + ST1, port); /* read MSCI ST1 status */
131 
132 	/* Reset MSCI TX underrun and CDCD (ignored) status bit */
133 	sca_out(stat & (ST1_UDRN | ST1_CDCD), MSCI0_OFFSET + ST1, port);
134 
135 	if (stat & ST1_UDRN) {
136 		/* TX Underrun error detected */
137 		port_to_dev(port)->stats.tx_errors++;
138 		port_to_dev(port)->stats.tx_fifo_errors++;
139 	}
140 
141 	stat = sca_in(MSCI1_OFFSET + ST1, port); /* read MSCI1 ST1 status */
142 	/* Reset MSCI CDCD status bit - uses ch#2 DCD input */
143 	sca_out(stat & ST1_CDCD, MSCI1_OFFSET + ST1, port);
144 
145 	if (stat & ST1_CDCD)
146 		set_carrier(port);
147 }
148 
149 
150 static void c101_set_iface(port_t *port)
151 {
152 	u8 rxs = port->rxs & CLK_BRG_MASK;
153 	u8 txs = port->txs & CLK_BRG_MASK;
154 
155 	switch(port->settings.clock_type) {
156 	case CLOCK_INT:
157 		rxs |= CLK_BRG_RX; /* TX clock */
158 		txs |= CLK_RXCLK_TX; /* BRG output */
159 		break;
160 
161 	case CLOCK_TXINT:
162 		rxs |= CLK_LINE_RX; /* RXC input */
163 		txs |= CLK_BRG_TX; /* BRG output */
164 		break;
165 
166 	case CLOCK_TXFROMRX:
167 		rxs |= CLK_LINE_RX; /* RXC input */
168 		txs |= CLK_RXCLK_TX; /* RX clock */
169 		break;
170 
171 	default:	/* EXTernal clock */
172 		rxs |= CLK_LINE_RX; /* RXC input */
173 		txs |= CLK_LINE_TX; /* TXC input */
174 	}
175 
176 	port->rxs = rxs;
177 	port->txs = txs;
178 	sca_out(rxs, MSCI1_OFFSET + RXS, port);
179 	sca_out(txs, MSCI1_OFFSET + TXS, port);
180 	sca_set_port(port);
181 }
182 
183 
184 static int c101_open(struct net_device *dev)
185 {
186 	port_t *port = dev_to_port(dev);
187 	int result;
188 
189 	result = hdlc_open(dev);
190 	if (result)
191 		return result;
192 
193 	writeb(1, port->win0base + C101_DTR);
194 	sca_out(0, MSCI1_OFFSET + CTL, port); /* RTS uses ch#2 output */
195 	sca_open(dev);
196 	/* DCD is connected to port 2 !@#$%^& - disable MSCI0 CDCD interrupt */
197 	sca_out(IE1_UDRN, MSCI0_OFFSET + IE1, port);
198 	sca_out(IE0_TXINT, MSCI0_OFFSET + IE0, port);
199 
200 	set_carrier(port);
201 
202 	/* enable MSCI1 CDCD interrupt */
203 	sca_out(IE1_CDCD, MSCI1_OFFSET + IE1, port);
204 	sca_out(IE0_RXINTA, MSCI1_OFFSET + IE0, port);
205 	sca_out(0x48, IER0, port); /* TXINT #0 and RXINT #1 */
206 	c101_set_iface(port);
207 	return 0;
208 }
209 
210 
211 static int c101_close(struct net_device *dev)
212 {
213 	port_t *port = dev_to_port(dev);
214 
215 	sca_close(dev);
216 	writeb(0, port->win0base + C101_DTR);
217 	sca_out(CTL_NORTS, MSCI1_OFFSET + CTL, port);
218 	hdlc_close(dev);
219 	return 0;
220 }
221 
222 
223 static int c101_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
224 {
225 	const size_t size = sizeof(sync_serial_settings);
226 	sync_serial_settings new_line;
227 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
228 	port_t *port = dev_to_port(dev);
229 
230 #ifdef DEBUG_RINGS
231 	if (cmd == SIOCDEVPRIVATE) {
232 		sca_dump_rings(dev);
233 		printk(KERN_DEBUG "MSCI1: ST: %02x %02x %02x %02x\n",
234 		       sca_in(MSCI1_OFFSET + ST0, port),
235 		       sca_in(MSCI1_OFFSET + ST1, port),
236 		       sca_in(MSCI1_OFFSET + ST2, port),
237 		       sca_in(MSCI1_OFFSET + ST3, port));
238 		return 0;
239 	}
240 #endif
241 	if (cmd != SIOCWANDEV)
242 		return hdlc_ioctl(dev, ifr, cmd);
243 
244 	switch(ifr->ifr_settings.type) {
245 	case IF_GET_IFACE:
246 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
247 		if (ifr->ifr_settings.size < size) {
248 			ifr->ifr_settings.size = size; /* data size wanted */
249 			return -ENOBUFS;
250 		}
251 		if (copy_to_user(line, &port->settings, size))
252 			return -EFAULT;
253 		return 0;
254 
255 	case IF_IFACE_SYNC_SERIAL:
256 		if(!capable(CAP_NET_ADMIN))
257 			return -EPERM;
258 
259 		if (copy_from_user(&new_line, line, size))
260 			return -EFAULT;
261 
262 		if (new_line.clock_type != CLOCK_EXT &&
263 		    new_line.clock_type != CLOCK_TXFROMRX &&
264 		    new_line.clock_type != CLOCK_INT &&
265 		    new_line.clock_type != CLOCK_TXINT)
266 		return -EINVAL;	/* No such clock setting */
267 
268 		if (new_line.loopback != 0 && new_line.loopback != 1)
269 			return -EINVAL;
270 
271 		memcpy(&port->settings, &new_line, size); /* Update settings */
272 		c101_set_iface(port);
273 		return 0;
274 
275 	default:
276 		return hdlc_ioctl(dev, ifr, cmd);
277 	}
278 }
279 
280 
281 
282 static void c101_destroy_card(card_t *card)
283 {
284 	readb(card->win0base + C101_PAGE); /* Resets SCA? */
285 
286 	if (card->irq)
287 		free_irq(card->irq, card);
288 
289 	if (card->win0base) {
290 		iounmap(card->win0base);
291 		release_mem_region(card->phy_winbase, C101_MAPPED_RAM_SIZE);
292 	}
293 
294 	free_netdev(card->dev);
295 
296 	kfree(card);
297 }
298 
299 static const struct net_device_ops c101_ops = {
300 	.ndo_open       = c101_open,
301 	.ndo_stop       = c101_close,
302 	.ndo_change_mtu = hdlc_change_mtu,
303 	.ndo_start_xmit = hdlc_start_xmit,
304 	.ndo_do_ioctl   = c101_ioctl,
305 };
306 
307 static int __init c101_run(unsigned long irq, unsigned long winbase)
308 {
309 	struct net_device *dev;
310 	hdlc_device *hdlc;
311 	card_t *card;
312 	int result;
313 
314 	if (irq<3 || irq>15 || irq == 6) /* FIXME */ {
315 		printk(KERN_ERR "c101: invalid IRQ value\n");
316 		return -ENODEV;
317 	}
318 
319 	if (winbase < 0xC0000 || winbase > 0xDFFFF || (winbase & 0x3FFF) !=0) {
320 		printk(KERN_ERR "c101: invalid RAM value\n");
321 		return -ENODEV;
322 	}
323 
324 	card = kzalloc(sizeof(card_t), GFP_KERNEL);
325 	if (card == NULL) {
326 		printk(KERN_ERR "c101: unable to allocate memory\n");
327 		return -ENOBUFS;
328 	}
329 
330 	card->dev = alloc_hdlcdev(card);
331 	if (!card->dev) {
332 		printk(KERN_ERR "c101: unable to allocate memory\n");
333 		kfree(card);
334 		return -ENOBUFS;
335 	}
336 
337 	if (request_irq(irq, sca_intr, 0, devname, card)) {
338 		printk(KERN_ERR "c101: could not allocate IRQ\n");
339 		c101_destroy_card(card);
340 		return -EBUSY;
341 	}
342 	card->irq = irq;
343 
344 	if (!request_mem_region(winbase, C101_MAPPED_RAM_SIZE, devname)) {
345 		printk(KERN_ERR "c101: could not request RAM window\n");
346 		c101_destroy_card(card);
347 		return -EBUSY;
348 	}
349 	card->phy_winbase = winbase;
350 	card->win0base = ioremap(winbase, C101_MAPPED_RAM_SIZE);
351 	if (!card->win0base) {
352 		printk(KERN_ERR "c101: could not map I/O address\n");
353 		c101_destroy_card(card);
354 		return -EFAULT;
355 	}
356 
357 	card->tx_ring_buffers = TX_RING_BUFFERS;
358 	card->rx_ring_buffers = RX_RING_BUFFERS;
359 	card->buff_offset = C101_WINDOW_SIZE; /* Bytes 1D00-1FFF reserved */
360 
361 	readb(card->win0base + C101_PAGE); /* Resets SCA? */
362 	udelay(100);
363 	writeb(0, card->win0base + C101_PAGE);
364 	writeb(0, card->win0base + C101_DTR); /* Power-up for RAM? */
365 
366 	sca_init(card, 0);
367 
368 	dev = port_to_dev(card);
369 	hdlc = dev_to_hdlc(dev);
370 
371 	spin_lock_init(&card->lock);
372 	dev->irq = irq;
373 	dev->mem_start = winbase;
374 	dev->mem_end = winbase + C101_MAPPED_RAM_SIZE - 1;
375 	dev->tx_queue_len = 50;
376 	dev->netdev_ops = &c101_ops;
377 	hdlc->attach = sca_attach;
378 	hdlc->xmit = sca_xmit;
379 	card->settings.clock_type = CLOCK_EXT;
380 
381 	result = register_hdlc_device(dev);
382 	if (result) {
383 		printk(KERN_WARNING "c101: unable to register hdlc device\n");
384 		c101_destroy_card(card);
385 		return result;
386 	}
387 
388 	sca_init_port(card); /* Set up C101 memory */
389 	set_carrier(card);
390 
391 	printk(KERN_INFO "%s: Moxa C101 on IRQ%u,"
392 	       " using %u TX + %u RX packets rings\n",
393 	       dev->name, card->irq,
394 	       card->tx_ring_buffers, card->rx_ring_buffers);
395 
396 	*new_card = card;
397 	new_card = &card->next_card;
398 	return 0;
399 }
400 
401 
402 
403 static int __init c101_init(void)
404 {
405 	if (hw == NULL) {
406 #ifdef MODULE
407 		printk(KERN_INFO "c101: no card initialized\n");
408 #endif
409 		return -EINVAL;	/* no parameters specified, abort */
410 	}
411 
412 	printk(KERN_INFO "%s\n", version);
413 
414 	do {
415 		unsigned long irq, ram;
416 
417 		irq = simple_strtoul(hw, &hw, 0);
418 
419 		if (*hw++ != ',')
420 			break;
421 		ram = simple_strtoul(hw, &hw, 0);
422 
423 		if (*hw == ':' || *hw == '\x0')
424 			c101_run(irq, ram);
425 
426 		if (*hw == '\x0')
427 			return first_card ? 0 : -EINVAL;
428 	}while(*hw++ == ':');
429 
430 	printk(KERN_ERR "c101: invalid hardware parameters\n");
431 	return first_card ? 0 : -EINVAL;
432 }
433 
434 
435 static void __exit c101_cleanup(void)
436 {
437 	card_t *card = first_card;
438 
439 	while (card) {
440 		card_t *ptr = card;
441 		card = card->next_card;
442 		unregister_hdlc_device(port_to_dev(ptr));
443 		c101_destroy_card(ptr);
444 	}
445 }
446 
447 
448 module_init(c101_init);
449 module_exit(c101_cleanup);
450 
451 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
452 MODULE_DESCRIPTION("Moxa C101 serial port driver");
453 MODULE_LICENSE("GPL v2");
454 module_param(hw, charp, 0444);
455 MODULE_PARM_DESC(hw, "irq,ram:irq,...");
456