xref: /openbmc/linux/drivers/net/wan/c101.c (revision 9b93eb47)
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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/string.h>
25 #include <linux/errno.h>
26 #include <linux/init.h>
27 #include <linux/netdevice.h>
28 #include <linux/hdlc.h>
29 #include <linux/delay.h>
30 #include <asm/io.h>
31 
32 #include "hd64570.h"
33 
34 
35 static const char* version = "Moxa C101 driver version: 1.15";
36 static const char* devname = "C101";
37 
38 #undef DEBUG_PKT
39 #define DEBUG_RINGS
40 
41 #define C101_PAGE 0x1D00
42 #define C101_DTR 0x1E00
43 #define C101_SCA 0x1F00
44 #define C101_WINDOW_SIZE 0x2000
45 #define C101_MAPPED_RAM_SIZE 0x4000
46 
47 #define RAM_SIZE (256 * 1024)
48 #define TX_RING_BUFFERS 10
49 #define RX_RING_BUFFERS ((RAM_SIZE - C101_WINDOW_SIZE) /		\
50 			 (sizeof(pkt_desc) + HDLC_MAX_MRU) - TX_RING_BUFFERS)
51 
52 #define CLOCK_BASE 9830400	/* 9.8304 MHz */
53 #define PAGE0_ALWAYS_MAPPED
54 
55 static char *hw;		/* pointer to hw=xxx command line string */
56 
57 
58 typedef struct card_s {
59 	struct net_device *dev;
60 	spinlock_t lock;	/* TX lock */
61 	u8 __iomem *win0base;	/* ISA window base address */
62 	u32 phy_winbase;	/* ISA physical base address */
63 	sync_serial_settings settings;
64 	int rxpart;		/* partial frame received, next frame invalid*/
65 	unsigned short encoding;
66 	unsigned short parity;
67 	u16 rx_ring_buffers;	/* number of buffers in a ring */
68 	u16 tx_ring_buffers;
69 	u16 buff_offset;	/* offset of first buffer of first channel */
70 	u16 rxin;		/* rx ring buffer 'in' pointer */
71 	u16 txin;		/* tx ring buffer 'in' and 'last' pointers */
72 	u16 txlast;
73 	u8 rxs, txs, tmc;	/* SCA registers */
74 	u8 irq;			/* IRQ (3-15) */
75 	u8 page;
76 
77 	struct card_s *next_card;
78 }card_t;
79 
80 typedef card_t port_t;
81 
82 static card_t *first_card;
83 static card_t **new_card = &first_card;
84 
85 
86 #define sca_in(reg, card)	   readb((card)->win0base + C101_SCA + (reg))
87 #define sca_out(value, reg, card)  writeb(value, (card)->win0base + C101_SCA + (reg))
88 #define sca_inw(reg, card)	   readw((card)->win0base + C101_SCA + (reg))
89 
90 /* EDA address register must be set in EDAL, EDAH order - 8 bit ISA bus */
91 #define sca_outw(value, reg, card) do { \
92 	writeb(value & 0xFF, (card)->win0base + C101_SCA + (reg)); \
93 	writeb((value >> 8 ) & 0xFF, (card)->win0base + C101_SCA + (reg + 1));\
94 } while(0)
95 
96 #define port_to_card(port)	   (port)
97 #define log_node(port)		   (0)
98 #define phy_node(port)		   (0)
99 #define winsize(card)		   (C101_WINDOW_SIZE)
100 #define win0base(card)		   ((card)->win0base)
101 #define winbase(card)      	   ((card)->win0base + 0x2000)
102 #define get_port(card, port)	   (card)
103 static void sca_msci_intr(port_t *port);
104 
105 
106 static inline u8 sca_get_page(card_t *card)
107 {
108 	return card->page;
109 }
110 
111 static inline void openwin(card_t *card, u8 page)
112 {
113 	card->page = page;
114 	writeb(page, card->win0base + C101_PAGE);
115 }
116 
117 
118 #include "hd64570.c"
119 
120 
121 static inline void set_carrier(port_t *port)
122 {
123 	if (!(sca_in(MSCI1_OFFSET + ST3, port) & ST3_DCD))
124 		netif_carrier_on(port_to_dev(port));
125 	else
126 		netif_carrier_off(port_to_dev(port));
127 }
128 
129 
130 static void sca_msci_intr(port_t *port)
131 {
132 	u8 stat = sca_in(MSCI0_OFFSET + ST1, port); /* read MSCI ST1 status */
133 
134 	/* Reset MSCI TX underrun and CDCD (ignored) status bit */
135 	sca_out(stat & (ST1_UDRN | ST1_CDCD), MSCI0_OFFSET + ST1, port);
136 
137 	if (stat & ST1_UDRN) {
138 		/* TX Underrun error detected */
139 		port_to_dev(port)->stats.tx_errors++;
140 		port_to_dev(port)->stats.tx_fifo_errors++;
141 	}
142 
143 	stat = sca_in(MSCI1_OFFSET + ST1, port); /* read MSCI1 ST1 status */
144 	/* Reset MSCI CDCD status bit - uses ch#2 DCD input */
145 	sca_out(stat & ST1_CDCD, MSCI1_OFFSET + ST1, port);
146 
147 	if (stat & ST1_CDCD)
148 		set_carrier(port);
149 }
150 
151 
152 static void c101_set_iface(port_t *port)
153 {
154 	u8 rxs = port->rxs & CLK_BRG_MASK;
155 	u8 txs = port->txs & CLK_BRG_MASK;
156 
157 	switch(port->settings.clock_type) {
158 	case CLOCK_INT:
159 		rxs |= CLK_BRG_RX; /* TX clock */
160 		txs |= CLK_RXCLK_TX; /* BRG output */
161 		break;
162 
163 	case CLOCK_TXINT:
164 		rxs |= CLK_LINE_RX; /* RXC input */
165 		txs |= CLK_BRG_TX; /* BRG output */
166 		break;
167 
168 	case CLOCK_TXFROMRX:
169 		rxs |= CLK_LINE_RX; /* RXC input */
170 		txs |= CLK_RXCLK_TX; /* RX clock */
171 		break;
172 
173 	default:	/* EXTernal clock */
174 		rxs |= CLK_LINE_RX; /* RXC input */
175 		txs |= CLK_LINE_TX; /* TXC input */
176 	}
177 
178 	port->rxs = rxs;
179 	port->txs = txs;
180 	sca_out(rxs, MSCI1_OFFSET + RXS, port);
181 	sca_out(txs, MSCI1_OFFSET + TXS, port);
182 	sca_set_port(port);
183 }
184 
185 
186 static int c101_open(struct net_device *dev)
187 {
188 	port_t *port = dev_to_port(dev);
189 	int result;
190 
191 	result = hdlc_open(dev);
192 	if (result)
193 		return result;
194 
195 	writeb(1, port->win0base + C101_DTR);
196 	sca_out(0, MSCI1_OFFSET + CTL, port); /* RTS uses ch#2 output */
197 	sca_open(dev);
198 	/* DCD is connected to port 2 !@#$%^& - disable MSCI0 CDCD interrupt */
199 	sca_out(IE1_UDRN, MSCI0_OFFSET + IE1, port);
200 	sca_out(IE0_TXINT, MSCI0_OFFSET + IE0, port);
201 
202 	set_carrier(port);
203 
204 	/* enable MSCI1 CDCD interrupt */
205 	sca_out(IE1_CDCD, MSCI1_OFFSET + IE1, port);
206 	sca_out(IE0_RXINTA, MSCI1_OFFSET + IE0, port);
207 	sca_out(0x48, IER0, port); /* TXINT #0 and RXINT #1 */
208 	c101_set_iface(port);
209 	return 0;
210 }
211 
212 
213 static int c101_close(struct net_device *dev)
214 {
215 	port_t *port = dev_to_port(dev);
216 
217 	sca_close(dev);
218 	writeb(0, port->win0base + C101_DTR);
219 	sca_out(CTL_NORTS, MSCI1_OFFSET + CTL, port);
220 	hdlc_close(dev);
221 	return 0;
222 }
223 
224 
225 static int c101_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
226 {
227 	const size_t size = sizeof(sync_serial_settings);
228 	sync_serial_settings new_line;
229 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
230 	port_t *port = dev_to_port(dev);
231 
232 #ifdef DEBUG_RINGS
233 	if (cmd == SIOCDEVPRIVATE) {
234 		sca_dump_rings(dev);
235 		printk(KERN_DEBUG "MSCI1: ST: %02x %02x %02x %02x\n",
236 		       sca_in(MSCI1_OFFSET + ST0, port),
237 		       sca_in(MSCI1_OFFSET + ST1, port),
238 		       sca_in(MSCI1_OFFSET + ST2, port),
239 		       sca_in(MSCI1_OFFSET + ST3, port));
240 		return 0;
241 	}
242 #endif
243 	if (cmd != SIOCWANDEV)
244 		return hdlc_ioctl(dev, ifr, cmd);
245 
246 	switch(ifr->ifr_settings.type) {
247 	case IF_GET_IFACE:
248 		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
249 		if (ifr->ifr_settings.size < size) {
250 			ifr->ifr_settings.size = size; /* data size wanted */
251 			return -ENOBUFS;
252 		}
253 		if (copy_to_user(line, &port->settings, size))
254 			return -EFAULT;
255 		return 0;
256 
257 	case IF_IFACE_SYNC_SERIAL:
258 		if(!capable(CAP_NET_ADMIN))
259 			return -EPERM;
260 
261 		if (copy_from_user(&new_line, line, size))
262 			return -EFAULT;
263 
264 		if (new_line.clock_type != CLOCK_EXT &&
265 		    new_line.clock_type != CLOCK_TXFROMRX &&
266 		    new_line.clock_type != CLOCK_INT &&
267 		    new_line.clock_type != CLOCK_TXINT)
268 			return -EINVAL;	/* No such clock setting */
269 
270 		if (new_line.loopback != 0 && new_line.loopback != 1)
271 			return -EINVAL;
272 
273 		memcpy(&port->settings, &new_line, size); /* Update settings */
274 		c101_set_iface(port);
275 		return 0;
276 
277 	default:
278 		return hdlc_ioctl(dev, ifr, cmd);
279 	}
280 }
281 
282 
283 
284 static void c101_destroy_card(card_t *card)
285 {
286 	readb(card->win0base + C101_PAGE); /* Resets SCA? */
287 
288 	if (card->irq)
289 		free_irq(card->irq, card);
290 
291 	if (card->win0base) {
292 		iounmap(card->win0base);
293 		release_mem_region(card->phy_winbase, C101_MAPPED_RAM_SIZE);
294 	}
295 
296 	free_netdev(card->dev);
297 
298 	kfree(card);
299 }
300 
301 static const struct net_device_ops c101_ops = {
302 	.ndo_open       = c101_open,
303 	.ndo_stop       = c101_close,
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 		pr_err("invalid IRQ value\n");
317 		return -ENODEV;
318 	}
319 
320 	if (winbase < 0xC0000 || winbase > 0xDFFFF || (winbase & 0x3FFF) !=0) {
321 		pr_err("invalid RAM value\n");
322 		return -ENODEV;
323 	}
324 
325 	card = kzalloc(sizeof(card_t), GFP_KERNEL);
326 	if (card == NULL)
327 		return -ENOBUFS;
328 
329 	card->dev = alloc_hdlcdev(card);
330 	if (!card->dev) {
331 		pr_err("unable to allocate memory\n");
332 		kfree(card);
333 		return -ENOBUFS;
334 	}
335 
336 	if (request_irq(irq, sca_intr, 0, devname, card)) {
337 		pr_err("could not allocate IRQ\n");
338 		c101_destroy_card(card);
339 		return -EBUSY;
340 	}
341 	card->irq = irq;
342 
343 	if (!request_mem_region(winbase, C101_MAPPED_RAM_SIZE, devname)) {
344 		pr_err("could not request RAM window\n");
345 		c101_destroy_card(card);
346 		return -EBUSY;
347 	}
348 	card->phy_winbase = winbase;
349 	card->win0base = ioremap(winbase, C101_MAPPED_RAM_SIZE);
350 	if (!card->win0base) {
351 		pr_err("could not map I/O address\n");
352 		c101_destroy_card(card);
353 		return -EFAULT;
354 	}
355 
356 	card->tx_ring_buffers = TX_RING_BUFFERS;
357 	card->rx_ring_buffers = RX_RING_BUFFERS;
358 	card->buff_offset = C101_WINDOW_SIZE; /* Bytes 1D00-1FFF reserved */
359 
360 	readb(card->win0base + C101_PAGE); /* Resets SCA? */
361 	udelay(100);
362 	writeb(0, card->win0base + C101_PAGE);
363 	writeb(0, card->win0base + C101_DTR); /* Power-up for RAM? */
364 
365 	sca_init(card, 0);
366 
367 	dev = port_to_dev(card);
368 	hdlc = dev_to_hdlc(dev);
369 
370 	spin_lock_init(&card->lock);
371 	dev->irq = irq;
372 	dev->mem_start = winbase;
373 	dev->mem_end = winbase + C101_MAPPED_RAM_SIZE - 1;
374 	dev->tx_queue_len = 50;
375 	dev->netdev_ops = &c101_ops;
376 	hdlc->attach = sca_attach;
377 	hdlc->xmit = sca_xmit;
378 	card->settings.clock_type = CLOCK_EXT;
379 
380 	result = register_hdlc_device(dev);
381 	if (result) {
382 		pr_warn("unable to register hdlc device\n");
383 		c101_destroy_card(card);
384 		return result;
385 	}
386 
387 	sca_init_port(card); /* Set up C101 memory */
388 	set_carrier(card);
389 
390 	netdev_info(dev, "Moxa C101 on IRQ%u, using %u TX + %u RX packets rings\n",
391 		    card->irq, card->tx_ring_buffers, card->rx_ring_buffers);
392 
393 	*new_card = card;
394 	new_card = &card->next_card;
395 	return 0;
396 }
397 
398 
399 
400 static int __init c101_init(void)
401 {
402 	if (hw == NULL) {
403 #ifdef MODULE
404 		pr_info("no card initialized\n");
405 #endif
406 		return -EINVAL;	/* no parameters specified, abort */
407 	}
408 
409 	pr_info("%s\n", version);
410 
411 	do {
412 		unsigned long irq, ram;
413 
414 		irq = simple_strtoul(hw, &hw, 0);
415 
416 		if (*hw++ != ',')
417 			break;
418 		ram = simple_strtoul(hw, &hw, 0);
419 
420 		if (*hw == ':' || *hw == '\x0')
421 			c101_run(irq, ram);
422 
423 		if (*hw == '\x0')
424 			return first_card ? 0 : -EINVAL;
425 	}while(*hw++ == ':');
426 
427 	pr_err("invalid hardware parameters\n");
428 	return first_card ? 0 : -EINVAL;
429 }
430 
431 
432 static void __exit c101_cleanup(void)
433 {
434 	card_t *card = first_card;
435 
436 	while (card) {
437 		card_t *ptr = card;
438 		card = card->next_card;
439 		unregister_hdlc_device(port_to_dev(ptr));
440 		c101_destroy_card(ptr);
441 	}
442 }
443 
444 
445 module_init(c101_init);
446 module_exit(c101_cleanup);
447 
448 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
449 MODULE_DESCRIPTION("Moxa C101 serial port driver");
450 MODULE_LICENSE("GPL v2");
451 module_param(hw, charp, 0444);
452 MODULE_PARM_DESC(hw, "irq,ram:irq,...");
453