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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* hermes.c
2 *
3 * Driver core for the "Hermes" wireless MAC controller, as used in
4 * the Lucent Orinoco and Cabletron RoamAbout cards. It should also
5 * work on the hfa3841 and hfa3842 MAC controller chips used in the
6 * Prism II chipsets.
7 *
8 * This is not a complete driver, just low-level access routines for
9 * the MAC controller itself.
10 *
11 * Based on the prism2 driver from Absolute Value Systems' linux-wlan
12 * project, the Linux wvlan_cs driver, Lucent's HCF-Light
13 * (wvlan_hcf.c) library, and the NetBSD wireless driver (in no
14 * particular order).
15 *
16 * Copyright (C) 2000, David Gibson, Linuxcare Australia.
17 * (C) Copyright David Gibson, IBM Corp. 2001-2003.
18 *
19 * The contents of this file are subject to the Mozilla Public License
20 * Version 1.1 (the "License"); you may not use this file except in
21 * compliance with the License. You may obtain a copy of the License
22 * at http://www.mozilla.org/MPL/
23 *
24 * Software distributed under the License is distributed on an "AS IS"
25 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
26 * the License for the specific language governing rights and
27 * limitations under the License.
28 *
29 * Alternatively, the contents of this file may be used under the
30 * terms of the GNU General Public License version 2 (the "GPL"), in
31 * which case the provisions of the GPL are applicable instead of the
32 * above. If you wish to allow the use of your version of this file
33 * only under the terms of the GPL and not to allow others to use your
34 * version of this file under the MPL, indicate your decision by
35 * deleting the provisions above and replace them with the notice and
36 * other provisions required by the GPL. If you do not delete the
37 * provisions above, a recipient may use your version of this file
38 * under either the MPL or the GPL.
39 */
40
41#include <linux/config.h>
42
43#include <linux/module.h>
44#include <linux/types.h>
45#include <linux/threads.h>
46#include <linux/smp.h>
47#include <asm/io.h>
48#include <linux/delay.h>
49#include <linux/init.h>
50#include <linux/kernel.h>
51#include <linux/net.h>
52#include <asm/errno.h>
53
54#include "hermes.h"
55
56MODULE_DESCRIPTION("Low-level driver helper for Lucent Hermes chipset and Prism II HFA384x wireless MAC controller");
57MODULE_AUTHOR("Pavel Roskin <proski@gnu.org>"
58 " & David Gibson <hermes@gibson.dropbear.id.au>");
59MODULE_LICENSE("Dual MPL/GPL");
60
61/* These are maximum timeouts. Most often, card wil react much faster */
62#define CMD_BUSY_TIMEOUT (100) /* In iterations of ~1us */
63#define CMD_INIT_TIMEOUT (50000) /* in iterations of ~10us */
64#define CMD_COMPL_TIMEOUT (20000) /* in iterations of ~10us */
65#define ALLOC_COMPL_TIMEOUT (1000) /* in iterations of ~10us */
66
67/*
68 * Debugging helpers
69 */
70
71#define DMSG(stuff...) do {printk(KERN_DEBUG "hermes @ %p: " , hw->iobase); \
72 printk(stuff);} while (0)
73
74#undef HERMES_DEBUG
75#ifdef HERMES_DEBUG
76#include <stdarg.h>
77
78#define DEBUG(lvl, stuff...) if ( (lvl) <= HERMES_DEBUG) DMSG(stuff)
79
80#else /* ! HERMES_DEBUG */
81
82#define DEBUG(lvl, stuff...) do { } while (0)
83
84#endif /* ! HERMES_DEBUG */
85
86
87/*
88 * Internal functions
89 */
90
91/* Issue a command to the chip. Waiting for it to complete is the caller's
92 problem.
93
94 Returns -EBUSY if the command register is busy, 0 on success.
95
96 Callable from any context.
97*/
98static int hermes_issue_cmd(hermes_t *hw, u16 cmd, u16 param0)
99{
100 int k = CMD_BUSY_TIMEOUT;
101 u16 reg;
102
103 /* First wait for the command register to unbusy */
104 reg = hermes_read_regn(hw, CMD);
105 while ( (reg & HERMES_CMD_BUSY) && k ) {
106 k--;
107 udelay(1);
108 reg = hermes_read_regn(hw, CMD);
109 }
110 if (reg & HERMES_CMD_BUSY) {
111 return -EBUSY;
112 }
113
114 hermes_write_regn(hw, PARAM2, 0);
115 hermes_write_regn(hw, PARAM1, 0);
116 hermes_write_regn(hw, PARAM0, param0);
117 hermes_write_regn(hw, CMD, cmd);
118
119 return 0;
120}
121
122/*
123 * Function definitions
124 */
125
126void hermes_struct_init(hermes_t *hw, void __iomem *address, int reg_spacing)
127{
128 hw->iobase = address;
129 hw->reg_spacing = reg_spacing;
130 hw->inten = 0x0;
131
132#ifdef HERMES_DEBUG_BUFFER
133 hw->dbufp = 0;
134 memset(&hw->dbuf, 0xff, sizeof(hw->dbuf));
135 memset(&hw->profile, 0, sizeof(hw->profile));
136#endif
137}
138
139int hermes_init(hermes_t *hw)
140{
141 u16 status, reg;
142 int err = 0;
143 int k;
144
145 /* We don't want to be interrupted while resetting the chipset */
146 hw->inten = 0x0;
147 hermes_write_regn(hw, INTEN, 0);
148 hermes_write_regn(hw, EVACK, 0xffff);
149
150 /* Normally it's a "can't happen" for the command register to
151 be busy when we go to issue a command because we are
152 serializing all commands. However we want to have some
153 chance of resetting the card even if it gets into a stupid
154 state, so we actually wait to see if the command register
155 will unbusy itself here. */
156 k = CMD_BUSY_TIMEOUT;
157 reg = hermes_read_regn(hw, CMD);
158 while (k && (reg & HERMES_CMD_BUSY)) {
159 if (reg == 0xffff) /* Special case - the card has probably been removed,
160 so don't wait for the timeout */
161 return -ENODEV;
162
163 k--;
164 udelay(1);
165 reg = hermes_read_regn(hw, CMD);
166 }
167
168 /* No need to explicitly handle the timeout - if we've timed
169 out hermes_issue_cmd() will probably return -EBUSY below */
170
171 /* According to the documentation, EVSTAT may contain
172 obsolete event occurrence information. We have to acknowledge
173 it by writing EVACK. */
174 reg = hermes_read_regn(hw, EVSTAT);
175 hermes_write_regn(hw, EVACK, reg);
176
177 /* We don't use hermes_docmd_wait here, because the reset wipes
178 the magic constant in SWSUPPORT0 away, and it gets confused */
179 err = hermes_issue_cmd(hw, HERMES_CMD_INIT, 0);
180 if (err)
181 return err;
182
183 reg = hermes_read_regn(hw, EVSTAT);
184 k = CMD_INIT_TIMEOUT;
185 while ( (! (reg & HERMES_EV_CMD)) && k) {
186 k--;
187 udelay(10);
188 reg = hermes_read_regn(hw, EVSTAT);
189 }
190
191 hermes_write_regn(hw, SWSUPPORT0, HERMES_MAGIC);
192
193 if (! hermes_present(hw)) {
194 DEBUG(0, "hermes @ 0x%x: Card removed during reset.\n",
195 hw->iobase);
196 err = -ENODEV;
197 goto out;
198 }
199
200 if (! (reg & HERMES_EV_CMD)) {
201 printk(KERN_ERR "hermes @ %p: "
202 "Timeout waiting for card to reset (reg=0x%04x)!\n",
203 hw->iobase, reg);
204 err = -ETIMEDOUT;
205 goto out;
206 }
207
208 status = hermes_read_regn(hw, STATUS);
209
210 hermes_write_regn(hw, EVACK, HERMES_EV_CMD);
211
212 if (status & HERMES_STATUS_RESULT)
213 err = -EIO;
214
215 out:
216 return err;
217}
218
219/* Issue a command to the chip, and (busy!) wait for it to
220 * complete.
221 *
222 * Returns: < 0 on internal error, 0 on success, > 0 on error returned by the firmware
223 *
224 * Callable from any context, but locking is your problem. */
225int hermes_docmd_wait(hermes_t *hw, u16 cmd, u16 parm0,
226 struct hermes_response *resp)
227{
228 int err;
229 int k;
230 u16 reg;
231 u16 status;
232
233 err = hermes_issue_cmd(hw, cmd, parm0);
234 if (err) {
235 if (! hermes_present(hw)) {
236 if (net_ratelimit())
237 printk(KERN_WARNING "hermes @ %p: "
238 "Card removed while issuing command "
239 "0x%04x.\n", hw->iobase, cmd);
240 err = -ENODEV;
241 } else
242 if (net_ratelimit())
243 printk(KERN_ERR "hermes @ %p: "
244 "Error %d issuing command 0x%04x.\n",
245 hw->iobase, err, cmd);
246 goto out;
247 }
248
249 reg = hermes_read_regn(hw, EVSTAT);
250 k = CMD_COMPL_TIMEOUT;
251 while ( (! (reg & HERMES_EV_CMD)) && k) {
252 k--;
253 udelay(10);
254 reg = hermes_read_regn(hw, EVSTAT);
255 }
256
257 if (! hermes_present(hw)) {
258 printk(KERN_WARNING "hermes @ %p: Card removed "
259 "while waiting for command 0x%04x completion.\n",
260 hw->iobase, cmd);
261 err = -ENODEV;
262 goto out;
263 }
264
265 if (! (reg & HERMES_EV_CMD)) {
266 printk(KERN_ERR "hermes @ %p: Timeout waiting for "
267 "command 0x%04x completion.\n", hw->iobase, cmd);
268 err = -ETIMEDOUT;
269 goto out;
270 }
271
272 status = hermes_read_regn(hw, STATUS);
273 if (resp) {
274 resp->status = status;
275 resp->resp0 = hermes_read_regn(hw, RESP0);
276 resp->resp1 = hermes_read_regn(hw, RESP1);
277 resp->resp2 = hermes_read_regn(hw, RESP2);
278 }
279
280 hermes_write_regn(hw, EVACK, HERMES_EV_CMD);
281
282 if (status & HERMES_STATUS_RESULT)
283 err = -EIO;
284
285 out:
286 return err;
287}
288
289int hermes_allocate(hermes_t *hw, u16 size, u16 *fid)
290{
291 int err = 0;
292 int k;
293 u16 reg;
294
295 if ( (size < HERMES_ALLOC_LEN_MIN) || (size > HERMES_ALLOC_LEN_MAX) )
296 return -EINVAL;
297
298 err = hermes_docmd_wait(hw, HERMES_CMD_ALLOC, size, NULL);
299 if (err) {
300 return err;
301 }
302
303 reg = hermes_read_regn(hw, EVSTAT);
304 k = ALLOC_COMPL_TIMEOUT;
305 while ( (! (reg & HERMES_EV_ALLOC)) && k) {
306 k--;
307 udelay(10);
308 reg = hermes_read_regn(hw, EVSTAT);
309 }
310
311 if (! hermes_present(hw)) {
312 printk(KERN_WARNING "hermes @ %p: "
313 "Card removed waiting for frame allocation.\n",
314 hw->iobase);
315 return -ENODEV;
316 }
317
318 if (! (reg & HERMES_EV_ALLOC)) {
319 printk(KERN_ERR "hermes @ %p: "
320 "Timeout waiting for frame allocation\n",
321 hw->iobase);
322 return -ETIMEDOUT;
323 }
324
325 *fid = hermes_read_regn(hw, ALLOCFID);
326 hermes_write_regn(hw, EVACK, HERMES_EV_ALLOC);
327
328 return 0;
329}
330
331
332/* Set up a BAP to read a particular chunk of data from card's internal buffer.
333 *
334 * Returns: < 0 on internal failure (errno), 0 on success, >0 on error
335 * from firmware
336 *
337 * Callable from any context */
338static int hermes_bap_seek(hermes_t *hw, int bap, u16 id, u16 offset)
339{
340 int sreg = bap ? HERMES_SELECT1 : HERMES_SELECT0;
341 int oreg = bap ? HERMES_OFFSET1 : HERMES_OFFSET0;
342 int k;
343 u16 reg;
344
345 /* Paranoia.. */
346 if ( (offset > HERMES_BAP_OFFSET_MAX) || (offset % 2) )
347 return -EINVAL;
348
349 k = HERMES_BAP_BUSY_TIMEOUT;
350 reg = hermes_read_reg(hw, oreg);
351 while ((reg & HERMES_OFFSET_BUSY) && k) {
352 k--;
353 udelay(1);
354 reg = hermes_read_reg(hw, oreg);
355 }
356
357#ifdef HERMES_DEBUG_BUFFER
358 hw->profile[HERMES_BAP_BUSY_TIMEOUT - k]++;
359
360 if (k < HERMES_BAP_BUSY_TIMEOUT) {
361 struct hermes_debug_entry *e =
362 &hw->dbuf[(hw->dbufp++) % HERMES_DEBUG_BUFSIZE];
363 e->bap = bap;
364 e->id = id;
365 e->offset = offset;
366 e->cycles = HERMES_BAP_BUSY_TIMEOUT - k;
367 }
368#endif
369
370 if (reg & HERMES_OFFSET_BUSY)
371 return -ETIMEDOUT;
372
373 /* Now we actually set up the transfer */
374 hermes_write_reg(hw, sreg, id);
375 hermes_write_reg(hw, oreg, offset);
376
377 /* Wait for the BAP to be ready */
378 k = HERMES_BAP_BUSY_TIMEOUT;
379 reg = hermes_read_reg(hw, oreg);
380 while ( (reg & (HERMES_OFFSET_BUSY | HERMES_OFFSET_ERR)) && k) {
381 k--;
382 udelay(1);
383 reg = hermes_read_reg(hw, oreg);
384 }
385
386 if (reg != offset) {
387 printk(KERN_ERR "hermes @ %p: BAP%d offset %s: "
388 "reg=0x%x id=0x%x offset=0x%x\n", hw->iobase, bap,
389 (reg & HERMES_OFFSET_BUSY) ? "timeout" : "error",
390 reg, id, offset);
391
392 if (reg & HERMES_OFFSET_BUSY) {
393 return -ETIMEDOUT;
394 }
395
396 return -EIO; /* error or wrong offset */
397 }
398
399 return 0;
400}
401
402/* Read a block of data from the chip's buffer, via the
403 * BAP. Synchronization/serialization is the caller's problem. len
404 * must be even.
405 *
406 * Returns: < 0 on internal failure (errno), 0 on success, > 0 on error from firmware
407 */
408int hermes_bap_pread(hermes_t *hw, int bap, void *buf, unsigned len,
409 u16 id, u16 offset)
410{
411 int dreg = bap ? HERMES_DATA1 : HERMES_DATA0;
412 int err = 0;
413
414 if ( (len < 0) || (len % 2) )
415 return -EINVAL;
416
417 err = hermes_bap_seek(hw, bap, id, offset);
418 if (err)
419 goto out;
420
421 /* Actually do the transfer */
422 hermes_read_words(hw, dreg, buf, len/2);
423
424 out:
425 return err;
426}
427
428/* Write a block of data to the chip's buffer, via the
429 * BAP. Synchronization/serialization is the caller's problem. len
430 * must be even.
431 *
432 * Returns: < 0 on internal failure (errno), 0 on success, > 0 on error from firmware
433 */
434int hermes_bap_pwrite(hermes_t *hw, int bap, const void *buf, unsigned len,
435 u16 id, u16 offset)
436{
437 int dreg = bap ? HERMES_DATA1 : HERMES_DATA0;
438 int err = 0;
439
440 if ( (len < 0) || (len % 2) )
441 return -EINVAL;
442
443 err = hermes_bap_seek(hw, bap, id, offset);
444 if (err)
445 goto out;
446
447 /* Actually do the transfer */
448 hermes_write_words(hw, dreg, buf, len/2);
449
450 out:
451 return err;
452}
453
454/* Read a Length-Type-Value record from the card.
455 *
456 * If length is NULL, we ignore the length read from the card, and
457 * read the entire buffer regardless. This is useful because some of
458 * the configuration records appear to have incorrect lengths in
459 * practice.
460 *
461 * Callable from user or bh context. */
462int hermes_read_ltv(hermes_t *hw, int bap, u16 rid, unsigned bufsize,
463 u16 *length, void *buf)
464{
465 int err = 0;
466 int dreg = bap ? HERMES_DATA1 : HERMES_DATA0;
467 u16 rlength, rtype;
468 unsigned nwords;
469
470 if ( (bufsize < 0) || (bufsize % 2) )
471 return -EINVAL;
472
473 err = hermes_docmd_wait(hw, HERMES_CMD_ACCESS, rid, NULL);
474 if (err)
475 return err;
476
477 err = hermes_bap_seek(hw, bap, rid, 0);
478 if (err)
479 return err;
480
481 rlength = hermes_read_reg(hw, dreg);
482
483 if (! rlength)
484 return -ENODATA;
485
486 rtype = hermes_read_reg(hw, dreg);
487
488 if (length)
489 *length = rlength;
490
491 if (rtype != rid)
492 printk(KERN_WARNING "hermes @ %p: %s(): "
493 "rid (0x%04x) does not match type (0x%04x)\n",
494 hw->iobase, __FUNCTION__, rid, rtype);
495 if (HERMES_RECLEN_TO_BYTES(rlength) > bufsize)
496 printk(KERN_WARNING "hermes @ %p: "
497 "Truncating LTV record from %d to %d bytes. "
498 "(rid=0x%04x, len=0x%04x)\n", hw->iobase,
499 HERMES_RECLEN_TO_BYTES(rlength), bufsize, rid, rlength);
500
501 nwords = min((unsigned)rlength - 1, bufsize / 2);
502 hermes_read_words(hw, dreg, buf, nwords);
503
504 return 0;
505}
506
507int hermes_write_ltv(hermes_t *hw, int bap, u16 rid,
508 u16 length, const void *value)
509{
510 int dreg = bap ? HERMES_DATA1 : HERMES_DATA0;
511 int err = 0;
512 unsigned count;
513
514 if (length == 0)
515 return -EINVAL;
516
517 err = hermes_bap_seek(hw, bap, rid, 0);
518 if (err)
519 return err;
520
521 hermes_write_reg(hw, dreg, length);
522 hermes_write_reg(hw, dreg, rid);
523
524 count = length - 1;
525
526 hermes_write_words(hw, dreg, value, count);
527
528 err = hermes_docmd_wait(hw, HERMES_CMD_ACCESS | HERMES_CMD_WRITE,
529 rid, NULL);
530
531 return err;
532}
533
534EXPORT_SYMBOL(hermes_struct_init);
535EXPORT_SYMBOL(hermes_init);
536EXPORT_SYMBOL(hermes_docmd_wait);
537EXPORT_SYMBOL(hermes_allocate);
538
539EXPORT_SYMBOL(hermes_bap_pread);
540EXPORT_SYMBOL(hermes_bap_pwrite);
541EXPORT_SYMBOL(hermes_read_ltv);
542EXPORT_SYMBOL(hermes_write_ltv);
543
544static int __init init_hermes(void)
545{
546 return 0;
547}
548
549static void __exit exit_hermes(void)
550{
551}
552
553module_init(init_hermes);
554module_exit(exit_hermes);