xref: /openbmc/linux/drivers/net/arcnet/arc-rimi.c (revision afba8b0a)
1 /*
2  * Linux ARCnet driver - "RIM I" (entirely mem-mapped) cards
3  *
4  * Written 1994-1999 by Avery Pennarun.
5  * Written 1999-2000 by Martin Mares <mj@ucw.cz>.
6  * Derived from skeleton.c by Donald Becker.
7  *
8  * Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
9  *  for sponsoring the further development of this driver.
10  *
11  * **********************
12  *
13  * The original copyright of skeleton.c was as follows:
14  *
15  * skeleton.c Written 1993 by Donald Becker.
16  * Copyright 1993 United States Government as represented by the
17  * Director, National Security Agency.  This software may only be used
18  * and distributed according to the terms of the GNU General Public License as
19  * modified by SRC, incorporated herein by reference.
20  *
21  * **********************
22  *
23  * For more details, see drivers/net/arcnet.c
24  *
25  * **********************
26  */
27 
28 #define pr_fmt(fmt) "arcnet:" KBUILD_MODNAME ": " fmt
29 
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/moduleparam.h>
33 #include <linux/ioport.h>
34 #include <linux/delay.h>
35 #include <linux/netdevice.h>
36 #include <linux/memblock.h>
37 #include <linux/init.h>
38 #include <linux/interrupt.h>
39 #include <linux/io.h>
40 
41 #include "arcdevice.h"
42 #include "com9026.h"
43 
44 /* Internal function declarations */
45 
46 static int arcrimi_probe(struct net_device *dev);
47 static int arcrimi_found(struct net_device *dev);
48 static void arcrimi_command(struct net_device *dev, int command);
49 static int arcrimi_status(struct net_device *dev);
50 static void arcrimi_setmask(struct net_device *dev, int mask);
51 static int arcrimi_reset(struct net_device *dev, int really_reset);
52 static void arcrimi_copy_to_card(struct net_device *dev, int bufnum, int offset,
53 				 void *buf, int count);
54 static void arcrimi_copy_from_card(struct net_device *dev, int bufnum,
55 				   int offset, void *buf, int count);
56 
57 /* Handy defines for ARCnet specific stuff */
58 
59 /* Amount of I/O memory used by the card */
60 #define BUFFER_SIZE	(512)
61 #define MIRROR_SIZE	(BUFFER_SIZE * 4)
62 
63 /* We cannot probe for a RIM I card; one reason is I don't know how to reset
64  * them.  In fact, we can't even get their node ID automatically.  So, we
65  * need to be passed a specific shmem address, IRQ, and node ID.
66  */
67 static int __init arcrimi_probe(struct net_device *dev)
68 {
69 	if (BUGLVL(D_NORMAL)) {
70 		pr_info("%s\n", "RIM I (entirely mem-mapped) support");
71 		pr_info("E-mail me if you actually test the RIM I driver, please!\n");
72 		pr_info("Given: node %02Xh, shmem %lXh, irq %d\n",
73 			dev->dev_addr[0], dev->mem_start, dev->irq);
74 	}
75 
76 	if (dev->mem_start <= 0 || dev->irq <= 0) {
77 		if (BUGLVL(D_NORMAL))
78 			pr_err("No autoprobe for RIM I; you must specify the shmem and irq!\n");
79 		return -ENODEV;
80 	}
81 	if (dev->dev_addr[0] == 0) {
82 		if (BUGLVL(D_NORMAL))
83 			pr_err("You need to specify your card's station ID!\n");
84 		return -ENODEV;
85 	}
86 	/* Grab the memory region at mem_start for MIRROR_SIZE bytes.
87 	 * Later in arcrimi_found() the real size will be determined
88 	 * and this reserve will be released and the correct size
89 	 * will be taken.
90 	 */
91 	if (!request_mem_region(dev->mem_start, MIRROR_SIZE, "arcnet (90xx)")) {
92 		if (BUGLVL(D_NORMAL))
93 			pr_notice("Card memory already allocated\n");
94 		return -ENODEV;
95 	}
96 	return arcrimi_found(dev);
97 }
98 
99 static int check_mirror(unsigned long addr, size_t size)
100 {
101 	void __iomem *p;
102 	int res = -1;
103 
104 	if (!request_mem_region(addr, size, "arcnet (90xx)"))
105 		return -1;
106 
107 	p = ioremap(addr, size);
108 	if (p) {
109 		if (arcnet_readb(p, COM9026_REG_R_STATUS) == TESTvalue)
110 			res = 1;
111 		else
112 			res = 0;
113 		iounmap(p);
114 	}
115 
116 	release_mem_region(addr, size);
117 	return res;
118 }
119 
120 /* Set up the struct net_device associated with this card.
121  * Called after probing succeeds.
122  */
123 static int __init arcrimi_found(struct net_device *dev)
124 {
125 	struct arcnet_local *lp;
126 	unsigned long first_mirror, last_mirror, shmem;
127 	void __iomem *p;
128 	int mirror_size;
129 	int err;
130 
131 	p = ioremap(dev->mem_start, MIRROR_SIZE);
132 	if (!p) {
133 		release_mem_region(dev->mem_start, MIRROR_SIZE);
134 		arc_printk(D_NORMAL, dev, "Can't ioremap\n");
135 		return -ENODEV;
136 	}
137 
138 	/* reserve the irq */
139 	if (request_irq(dev->irq, arcnet_interrupt, 0, "arcnet (RIM I)", dev)) {
140 		iounmap(p);
141 		release_mem_region(dev->mem_start, MIRROR_SIZE);
142 		arc_printk(D_NORMAL, dev, "Can't get IRQ %d!\n", dev->irq);
143 		return -ENODEV;
144 	}
145 
146 	shmem = dev->mem_start;
147 	arcnet_writeb(TESTvalue, p, COM9026_REG_W_INTMASK);
148 	arcnet_writeb(TESTvalue, p, COM9026_REG_W_COMMAND);
149 					/* actually the station/node ID */
150 
151 	/* find the real shared memory start/end points, including mirrors */
152 
153 	/* guess the actual size of one "memory mirror" - the number of
154 	 * bytes between copies of the shared memory.  On most cards, it's
155 	 * 2k (or there are no mirrors at all) but on some, it's 4k.
156 	 */
157 	mirror_size = MIRROR_SIZE;
158 	if (arcnet_readb(p, COM9026_REG_R_STATUS) == TESTvalue &&
159 	    check_mirror(shmem - MIRROR_SIZE, MIRROR_SIZE) == 0 &&
160 	    check_mirror(shmem - 2 * MIRROR_SIZE, MIRROR_SIZE) == 1)
161 		mirror_size = 2 * MIRROR_SIZE;
162 
163 	first_mirror = shmem - mirror_size;
164 	while (check_mirror(first_mirror, mirror_size) == 1)
165 		first_mirror -= mirror_size;
166 	first_mirror += mirror_size;
167 
168 	last_mirror = shmem + mirror_size;
169 	while (check_mirror(last_mirror, mirror_size) == 1)
170 		last_mirror += mirror_size;
171 	last_mirror -= mirror_size;
172 
173 	dev->mem_start = first_mirror;
174 	dev->mem_end = last_mirror + MIRROR_SIZE - 1;
175 
176 	/* initialize the rest of the device structure. */
177 
178 	lp = netdev_priv(dev);
179 	lp->card_name = "RIM I";
180 	lp->hw.command = arcrimi_command;
181 	lp->hw.status = arcrimi_status;
182 	lp->hw.intmask = arcrimi_setmask;
183 	lp->hw.reset = arcrimi_reset;
184 	lp->hw.owner = THIS_MODULE;
185 	lp->hw.copy_to_card = arcrimi_copy_to_card;
186 	lp->hw.copy_from_card = arcrimi_copy_from_card;
187 
188 	/* re-reserve the memory region - arcrimi_probe() alloced this reqion
189 	 * but didn't know the real size.  Free that region and then re-get
190 	 * with the correct size.  There is a VERY slim chance this could
191 	 * fail.
192 	 */
193 	iounmap(p);
194 	release_mem_region(shmem, MIRROR_SIZE);
195 	if (!request_mem_region(dev->mem_start,
196 				dev->mem_end - dev->mem_start + 1,
197 				"arcnet (90xx)")) {
198 		arc_printk(D_NORMAL, dev, "Card memory already allocated\n");
199 		goto err_free_irq;
200 	}
201 
202 	lp->mem_start = ioremap(dev->mem_start,
203 				dev->mem_end - dev->mem_start + 1);
204 	if (!lp->mem_start) {
205 		arc_printk(D_NORMAL, dev, "Can't remap device memory!\n");
206 		goto err_release_mem;
207 	}
208 
209 	/* get and check the station ID from offset 1 in shmem */
210 	dev->dev_addr[0] = arcnet_readb(lp->mem_start, COM9026_REG_R_STATION);
211 
212 	arc_printk(D_NORMAL, dev, "ARCnet RIM I: station %02Xh found at IRQ %d, ShMem %lXh (%ld*%d bytes)\n",
213 		   dev->dev_addr[0],
214 		   dev->irq, dev->mem_start,
215 		   (dev->mem_end - dev->mem_start + 1) / mirror_size,
216 		   mirror_size);
217 
218 	err = register_netdev(dev);
219 	if (err)
220 		goto err_unmap;
221 
222 	return 0;
223 
224 err_unmap:
225 	iounmap(lp->mem_start);
226 err_release_mem:
227 	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
228 err_free_irq:
229 	free_irq(dev->irq, dev);
230 	return -EIO;
231 }
232 
233 /* Do a hardware reset on the card, and set up necessary registers.
234  *
235  * This should be called as little as possible, because it disrupts the
236  * token on the network (causes a RECON) and requires a significant delay.
237  *
238  * However, it does make sure the card is in a defined state.
239  */
240 static int arcrimi_reset(struct net_device *dev, int really_reset)
241 {
242 	struct arcnet_local *lp = netdev_priv(dev);
243 	void __iomem *ioaddr = lp->mem_start + 0x800;
244 
245 	arc_printk(D_INIT, dev, "Resetting %s (status=%02Xh)\n",
246 		   dev->name, arcnet_readb(ioaddr, COM9026_REG_R_STATUS));
247 
248 	if (really_reset) {
249 		arcnet_writeb(TESTvalue, ioaddr, -0x800);	/* fake reset */
250 		return 0;
251 	}
252 	/* clear flags & end reset */
253 	arcnet_writeb(CFLAGScmd | RESETclear, ioaddr, COM9026_REG_W_COMMAND);
254 	arcnet_writeb(CFLAGScmd | CONFIGclear, ioaddr, COM9026_REG_W_COMMAND);
255 
256 	/* enable extended (512-byte) packets */
257 	arcnet_writeb(CONFIGcmd | EXTconf, ioaddr, COM9026_REG_W_COMMAND);
258 
259 	/* done!  return success. */
260 	return 0;
261 }
262 
263 static void arcrimi_setmask(struct net_device *dev, int mask)
264 {
265 	struct arcnet_local *lp = netdev_priv(dev);
266 	void __iomem *ioaddr = lp->mem_start + 0x800;
267 
268 	arcnet_writeb(mask, ioaddr, COM9026_REG_W_INTMASK);
269 }
270 
271 static int arcrimi_status(struct net_device *dev)
272 {
273 	struct arcnet_local *lp = netdev_priv(dev);
274 	void __iomem *ioaddr = lp->mem_start + 0x800;
275 
276 	return arcnet_readb(ioaddr, COM9026_REG_R_STATUS);
277 }
278 
279 static void arcrimi_command(struct net_device *dev, int cmd)
280 {
281 	struct arcnet_local *lp = netdev_priv(dev);
282 	void __iomem *ioaddr = lp->mem_start + 0x800;
283 
284 	arcnet_writeb(cmd, ioaddr, COM9026_REG_W_COMMAND);
285 }
286 
287 static void arcrimi_copy_to_card(struct net_device *dev, int bufnum, int offset,
288 				 void *buf, int count)
289 {
290 	struct arcnet_local *lp = netdev_priv(dev);
291 	void __iomem *memaddr = lp->mem_start + 0x800 + bufnum * 512 + offset;
292 
293 	TIME(dev, "memcpy_toio", count, memcpy_toio(memaddr, buf, count));
294 }
295 
296 static void arcrimi_copy_from_card(struct net_device *dev, int bufnum,
297 				   int offset, void *buf, int count)
298 {
299 	struct arcnet_local *lp = netdev_priv(dev);
300 	void __iomem *memaddr = lp->mem_start + 0x800 + bufnum * 512 + offset;
301 
302 	TIME(dev, "memcpy_fromio", count, memcpy_fromio(buf, memaddr, count));
303 }
304 
305 static int node;
306 static int io;			/* use the insmod io= irq= node= options */
307 static int irq;
308 static char device[9];		/* use eg. device=arc1 to change name */
309 
310 module_param(node, int, 0);
311 module_param(io, int, 0);
312 module_param(irq, int, 0);
313 module_param_string(device, device, sizeof(device), 0);
314 MODULE_LICENSE("GPL");
315 
316 static struct net_device *my_dev;
317 
318 static int __init arc_rimi_init(void)
319 {
320 	struct net_device *dev;
321 
322 	dev = alloc_arcdev(device);
323 	if (!dev)
324 		return -ENOMEM;
325 
326 	if (node && node != 0xff)
327 		dev->dev_addr[0] = node;
328 
329 	dev->mem_start = io;
330 	dev->irq = irq;
331 	if (dev->irq == 2)
332 		dev->irq = 9;
333 
334 	if (arcrimi_probe(dev)) {
335 		free_netdev(dev);
336 		return -EIO;
337 	}
338 
339 	my_dev = dev;
340 	return 0;
341 }
342 
343 static void __exit arc_rimi_exit(void)
344 {
345 	struct net_device *dev = my_dev;
346 	struct arcnet_local *lp = netdev_priv(dev);
347 
348 	unregister_netdev(dev);
349 	iounmap(lp->mem_start);
350 	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
351 	free_irq(dev->irq, dev);
352 	free_netdev(dev);
353 }
354 
355 #ifndef MODULE
356 static int __init arcrimi_setup(char *s)
357 {
358 	int ints[8];
359 
360 	s = get_options(s, 8, ints);
361 	if (!ints[0])
362 		return 1;
363 	switch (ints[0]) {
364 	default:		/* ERROR */
365 		pr_err("Too many arguments\n");
366 		fallthrough;
367 	case 3:		/* Node ID */
368 		node = ints[3];
369 		fallthrough;
370 	case 2:		/* IRQ */
371 		irq = ints[2];
372 		fallthrough;
373 	case 1:		/* IO address */
374 		io = ints[1];
375 	}
376 	if (*s)
377 		snprintf(device, sizeof(device), "%s", s);
378 	return 1;
379 }
380 __setup("arcrimi=", arcrimi_setup);
381 #endif				/* MODULE */
382 
383 module_init(arc_rimi_init)
384 module_exit(arc_rimi_exit)
385