1 /*
2 * Flash memory interface rev.5 driver for the Intel
3 * Flash chips used on the NetWinder.
4 *
5 * 20/08/2000 RMK use __ioremap to map flash into virtual memory
6 * make a few more places use "volatile"
7 */
8
9 #include <linux/module.h>
10 #include <linux/types.h>
11 #include <linux/fs.h>
12 #include <linux/errno.h>
13 #include <linux/mm.h>
14 #include <linux/delay.h>
15 #include <linux/proc_fs.h>
16 #include <linux/sched.h>
17 #include <linux/miscdevice.h>
18 #include <linux/spinlock.h>
19 #include <linux/init.h>
20
21 #include <asm/hardware/dec21285.h>
22 #include <asm/io.h>
23 #include <asm/leds.h>
24 #include <asm/mach-types.h>
25 #include <asm/system.h>
26 #include <asm/uaccess.h>
27
28 /*****************************************************************************/
29 #include <asm/nwflash.h>
30
31 //#define MINIKERNEL 1 //export flash write, erase routines for MiniKernel
32
33 #ifndef MINIKERNEL
34 #define MSTATIC static
35 #else
36 #define MSTATIC
37 #endif
38
39 #define NWFLASH_VERSION "6.3"
40
41 MSTATIC void kick_open(void);
42 MSTATIC int get_flash_id(void);
43 MSTATIC int erase_block(int nBlock);
44 MSTATIC int write_block(unsigned long p, const char *buf, int count);
45 static int open_flash(struct inode *inodep, struct file *filep);
46 static int flash_ioctl(struct inode *inodep, struct file *filep, unsigned int cmd, unsigned long arg);
47 static ssize_t flash_read(struct file *file, char *buf, size_t count, loff_t * ppos);
48 static ssize_t flash_write(struct file *file, const char *buf, size_t count, loff_t * ppos);
49 static long long flash_llseek(struct file *file, long long offset, int orig);
50
51 #define KFLASH_SIZE 1024*1024 //1 Meg
52 #define KFLASH_SIZE4 4*1024*1024 //4 Meg
53 #define KFLASH_ID 0x89A6 //Intel flash
54 #define KFLASH_ID4 0xB0D4 //Intel flash 4Meg
55
56 static int flashdebug; //if set - we will display progress msgs
57
58 static int gbWriteEnable;
59 static int gbWriteBase64Enable;
60 static volatile unsigned char *FLASH_BASE;
61 MSTATIC int gbFlashSize = KFLASH_SIZE;
62
63 extern spinlock_t gpio_lock;
64
65 static struct file_operations flash_fops =
66 {
67 owner: THIS_MODULE,
68 llseek: flash_llseek,
69 read: flash_read,
70 write: flash_write,
71 ioctl: flash_ioctl,
72 open: open_flash,
73 };
74
75 static struct miscdevice flash_miscdev =
76 {
77 FLASH_MINOR,
78 "nwflash",
79 &flash_fops
80 };
81
82 /*
83 * the delay routine - it is often required to let the flash "breeze"...
84 */
85 void flash_wait(int timeout)
86 {
87 current->state = TASK_INTERRUPTIBLE;
88 schedule_timeout(timeout);
89 }
90
91 MSTATIC int get_flash_id(void)
92 {
93 volatile unsigned int c1, c2;
94
95 /*
96 * try to get flash chip ID
97 */
98 kick_open();
99 c2 = inb(0x80);
100 *(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x90;
101 udelay(15);
102 c1 = *(volatile unsigned char *) FLASH_BASE;
103 c2 = inb(0x80);
104
105 /*
106 * on 4 Meg flash the second byte is actually at offset 2...
107 */
108 if (c1 == 0xB0)
109 c2 = *(volatile unsigned char *) (FLASH_BASE + 2);
110 else
111 c2 = *(volatile unsigned char *) (FLASH_BASE + 1);
112
113 c2 += (c1 << 8);
114
115 /*
116 * set it back to read mode
117 */
118 *(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0xFF;
119
120 if (c2 == KFLASH_ID4)
121 gbFlashSize = KFLASH_SIZE4;
122
123 return c2;
124 }
125
126 static int open_flash(struct inode *inodep, struct file *filep)
127 {
128 int id;
129
130 id = get_flash_id();
131 if ((id != KFLASH_ID) && (id != KFLASH_ID4)) {
132 printk("Flash: incorrect ID 0x%04X.\n", id);
133 return -ENXIO;
134 }
135
136 return 0;
137 }
138
139 static int flash_ioctl(struct inode *inodep, struct file *filep, unsigned int cmd, unsigned long arg)
140 {
141 // printk("Flash_ioctl: cmd = 0x%X.\n",cmd);
142
143 switch (cmd) {
144 case CMD_WRITE_DISABLE:
145 gbWriteBase64Enable = 0;
146 gbWriteEnable = 0;
147 break;
148
149 case CMD_WRITE_ENABLE:
150 gbWriteEnable = 1;
151 break;
152
153 case CMD_WRITE_BASE64K_ENABLE:
154 gbWriteBase64Enable = 1;
155 break;
156
157 default:
158 gbWriteBase64Enable = 0;
159 gbWriteEnable = 0;
160 return -EINVAL;
161 }
162
163 return 0;
164 }
165
166
167
168 static ssize_t flash_read(struct file *file, char *buf, size_t count, loff_t * ppos)
169 {
170 unsigned long p = file->f_pos;
171 int read;
172
173 if (flashdebug)
174 printk("Flash_dev: flash_read: offset=0x%X, buffer=0x%X, count=0x%X.\n",
175 (unsigned int) p, (unsigned int) buf, count);
176
177
178 if (count < 0)
179 return -EINVAL;
180
181 if (count > gbFlashSize - p)
182 count = gbFlashSize - p;
183
184 read = 0;
185
186 if (copy_to_user(buf, (void *)(FLASH_BASE + p), count))
187 return -EFAULT;
188 read += count;
189 file->f_pos += read;
190 return read;
191 }
192
193 static ssize_t flash_write(struct file *file, const char *buf, size_t count, loff_t * ppos)
194 {
195 struct inode *inode = file->f_dentry->d_inode;
196 unsigned long p = file->f_pos;
197 int written;
198 int nBlock, temp, rc;
199 int i, j;
200
201 if (flashdebug)
202 printk("flash_write: offset=0x%lX, buffer=0x%p, count=0x%X.\n",
203 p, buf, count);
204
205 if (!gbWriteEnable)
206 return -EINVAL;
207
208 if (p < 64 * 1024 && (!gbWriteBase64Enable))
209 return -EINVAL;
210
211 /*
212 * if byte count is -ve or to big - error!
213 */
214 if (count < 0 || count > gbFlashSize - p)
215 return -EINVAL;
216
217 if (verify_area(VERIFY_READ, buf, count))
218 return -EFAULT;
219
220
221 /*
222 * We now should lock around writes. Really, we shouldn't
223 * allow the flash to be opened more than once in write
224 * mode though (note that you can't stop two processes having
225 * it open even then). --rmk
226 */
227 if (down_interruptible(&inode->i_sem))
228 return -ERESTARTSYS;
229
230 written = 0;
231
232 leds_event(led_claim);
233 leds_event(led_green_on);
234
235 nBlock = (int) p >> 16; //block # of 64K bytes
236
237 /*
238 * # of 64K blocks to erase and write
239 */
240 temp = ((int) (p + count) >> 16) - nBlock + 1;
241
242 /*
243 * write ends at exactly 64k boundry?
244 */
245 if (((int) (p + count) & 0xFFFF) == 0)
246 temp -= 1;
247
248 if (flashdebug)
249 printk("FlashWrite: writing %d block(s) starting at %d.\n", temp, nBlock);
250
251 for (; temp; temp--, nBlock++) {
252 if (flashdebug)
253 printk("FlashWrite: erasing block %d.\n", nBlock);
254
255 /*
256 * first we have to erase the block(s), where we will write...
257 */
258 i = 0;
259 j = 0;
260 RetryBlock:
261 do {
262 rc = erase_block(nBlock);
263 i++;
264 } while (rc && i < 10);
265
266 if (rc) {
267 if (flashdebug)
268 printk("FlashWrite: erase error %X. Aborting...\n", rc);
269
270 break;
271 }
272 if (flashdebug)
273 printk("FlashWrite: writing offset %X, from buf %X, bytes left %X.\n",
274 (unsigned int) p, (unsigned int) buf, count - written);
275
276 /*
277 * write_block will limit write to space left in this block
278 */
279 rc = write_block(p, buf, count - written);
280 j++;
281
282 /*
283 * if somehow write verify failed? Can't happen??
284 */
285 if (!rc) {
286 /*
287 * retry up to 10 times
288 */
289 if (j < 10)
290 goto RetryBlock;
291 else
292 /*
293 * else quit with error...
294 */
295 rc = -1;
296
297 }
298 if (rc < 0) {
299 if (flashdebug)
300 printk("FlashWrite: write error %X. Aborting...\n", rc);
301 break;
302 }
303 p += rc;
304 buf += rc;
305 written += rc;
306 file->f_pos += rc;
307
308 if (flashdebug)
309 printk("FlashWrite: written 0x%X bytes OK.\n", written);
310 }
311
312 /*
313 * restore reg on exit
314 */
315 leds_event(led_release);
316
317 up(&inode->i_sem);
318
319 return written;
320 }
321
322
323 /*
324 * The memory devices use the full 32/64 bits of the offset, and so we cannot
325 * check against negative addresses: they are ok. The return value is weird,
326 * though, in that case (0).
327 *
328 * also note that seeking relative to the "end of file" isn't supported:
329 * it has no meaning, so it returns -EINVAL.
330 */
331 static long long flash_llseek(struct file *file, long long offset, int orig)
332 {
333 if (flashdebug)
334 printk("Flash_dev: flash_lseek, offset=0x%X, orig=0x%X.\n",
335 (unsigned int) offset, (unsigned int) orig);
336
337 switch (orig) {
338 case 0:
339 if (offset < 0)
340 return -EINVAL;
341
342 if ((unsigned int) offset > gbFlashSize)
343 return -EINVAL;
344
345 file->f_pos = (unsigned int) offset;
346 return file->f_pos;
347 case 1:
348 if ((file->f_pos + offset) > gbFlashSize)
349 return -EINVAL;
350 if ((file->f_pos + offset) < 0)
351 return -EINVAL;
352 file->f_pos += offset;
353 return file->f_pos;
354 default:
355 return -EINVAL;
356 }
357 }
358
359
360 /*
361 * assume that main Write routine did the parameter checking...
362 * so just go ahead and erase, what requested!
363 */
364
365 MSTATIC int erase_block(int nBlock)
366 {
367 volatile unsigned int c1;
368 volatile unsigned char *pWritePtr;
369 int temp, temp1;
370
371 /*
372 * orange LED == erase
373 */
374 leds_event(led_amber_on);
375
376 /*
377 * reset footbridge to the correct offset 0 (...0..3)
378 */
379 *CSR_ROMWRITEREG = 0;
380
381 /*
382 * dummy ROM read
383 */
384 c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
385
386 kick_open();
387 /*
388 * reset status if old errors
389 */
390 *(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
391
392 /*
393 * erase a block...
394 * aim at the middle of a current block...
395 */
396 pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + 0x8000 + (nBlock << 16)));
397 /*
398 * dummy read
399 */
400 c1 = *pWritePtr;
401
402 kick_open();
403 /*
404 * erase
405 */
406 *(volatile unsigned char *) pWritePtr = 0x20;
407
408 /*
409 * confirm
410 */
411 *(volatile unsigned char *) pWritePtr = 0xD0;
412
413 /*
414 * wait 10 ms
415 */
416 flash_wait(HZ / 100);
417
418 /*
419 * wait while erasing in process (up to 10 sec)
420 */
421 temp = jiffies + 10 * HZ;
422 c1 = 0;
423 while (!(c1 & 0x80) && time_before(jiffies, temp)) {
424 flash_wait(HZ / 100);
425 /*
426 * read any address
427 */
428 c1 = *(volatile unsigned char *) (pWritePtr);
429 // printk("Flash_erase: status=%X.\n",c1);
430 }
431
432 /*
433 * set flash for normal read access
434 */
435 kick_open();
436 // *(volatile unsigned char*)(FLASH_BASE+0x8000) = 0xFF;
437 *(volatile unsigned char *) pWritePtr = 0xFF; //back to normal operation
438
439 /*
440 * check if erase errors were reported
441 */
442 if (c1 & 0x20) {
443 if (flashdebug)
444 printk("Flash_erase: err at %X.\n", (unsigned int) pWritePtr);
445 /*
446 * reset error
447 */
448 *(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
449
450 return -2;
451 }
452
453 /*
454 * just to make sure - verify if erased OK...
455 */
456 flash_wait(HZ / 100);
457
458 pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + (nBlock << 16)));
459
460 for (temp = 0; temp < 16 * 1024; temp++, pWritePtr += 4) {
461 if ((temp1 = *(volatile unsigned int *) pWritePtr) != 0xFFFFFFFF) {
462 if (flashdebug)
463 printk("Flash_erase: verify err at %X = %X.\n",
464 (unsigned int) pWritePtr, temp1);
465 return -1;
466 }
467 }
468
469 return 0;
470
471 }
472
473 /*
474 * write_block will limit number of bytes written to the space in this block
475 */
476 MSTATIC int write_block(unsigned long p, const char *buf, int count)
477 {
478 volatile unsigned int c1;
479 volatile unsigned int c2;
480 unsigned char *pWritePtr;
481 unsigned int uAddress;
482 unsigned int offset;
483 unsigned int timeout;
484 unsigned int timeout1;
485
486 /*
487 * red LED == write
488 */
489 leds_event(led_amber_off);
490 leds_event(led_red_on);
491
492 pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + p));
493
494 /*
495 * check if write will end in this block....
496 */
497 offset = p & 0xFFFF;
498
499 if (offset + count > 0x10000)
500 count = 0x10000 - offset;
501
502 /*
503 * wait up to 30 sec for this block
504 */
505 timeout = jiffies + 30 * HZ;
506
507 for (offset = 0; offset < count; offset++, pWritePtr++) {
508 uAddress = (unsigned int) pWritePtr;
509 uAddress &= 0xFFFFFFFC;
510 if (__get_user(c2, buf + offset))
511 return -EFAULT;
512
513 WriteRetry:
514 /*
515 * dummy read
516 */
517 c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
518
519 /*
520 * kick open the write gate
521 */
522 kick_open();
523
524 /*
525 * program footbridge to the correct offset...0..3
526 */
527 *CSR_ROMWRITEREG = (unsigned int) pWritePtr & 3;
528
529 /*
530 * write cmd
531 */
532 *(volatile unsigned char *) (uAddress) = 0x40;
533
534 /*
535 * data to write
536 */
537 *(volatile unsigned char *) (uAddress) = c2;
538
539 /*
540 * get status
541 */
542 *(volatile unsigned char *) (FLASH_BASE + 0x10000) = 0x70;
543
544 c1 = 0;
545
546 /*
547 * wait up to 1 sec for this byte
548 */
549 timeout1 = jiffies + 1 * HZ;
550
551 /*
552 * while not ready...
553 */
554 while (!(c1 & 0x80) && time_before(jiffies, timeout1))
555 c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
556
557 /*
558 * if timeout getting status
559 */
560 if (time_after_eq(jiffies, timeout1)) {
561 kick_open();
562 /*
563 * reset err
564 */
565 *(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
566
567 goto WriteRetry;
568 }
569 /*
570 * switch on read access, as a default flash operation mode
571 */
572 kick_open();
573 /*
574 * read access
575 */
576 *(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0xFF;
577
578 /*
579 * if hardware reports an error writing, and not timeout -
580 * reset the chip and retry
581 */
582 if (c1 & 0x10) {
583 kick_open();
584 /*
585 * reset err
586 */
587 *(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
588
589 /*
590 * before timeout?
591 */
592 if (time_before(jiffies, timeout)) {
593 if (flashdebug)
594 printk("FlashWrite: Retrying write (addr=0x%X)...\n",
595 pWritePtr - FLASH_BASE);
596
597 /*
598 * no LED == waiting
599 */
600 leds_event(led_amber_off);
601 /*
602 * wait couple ms
603 */
604 flash_wait(HZ / 100);
605 /*
606 * red LED == write
607 */
608 leds_event(led_red_on);
609
610 goto WriteRetry;
611 } else {
612 printk("Timeout in flash write! (addr=0x%X) Aborting...\n",
613 pWritePtr - FLASH_BASE);
614 /*
615 * return error -2
616 */
617 return -2;
618
619 }
620 }
621 }
622
623 /*
624 * green LED == read/verify
625 */
626 leds_event(led_amber_off);
627 leds_event(led_green_on);
628
629 flash_wait(HZ / 100);
630
631 pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + p));
632
633 for (offset = 0; offset < count; offset++) {
634 char c, c1;
635 if (__get_user(c, buf))
636 return -EFAULT;
637 buf++;
638 if ((c1 = *pWritePtr++) != c) {
639 if (flashdebug)
640 printk("flash write verify error at 0x%X! (%02X!=%02X) Retrying...\n",
641 (unsigned int) pWritePtr, c1, c);
642 return 0;
643 }
644 }
645
646 return count;
647 }
648
649
650 MSTATIC void kick_open(void)
651 {
652 unsigned long flags;
653
654 /*
655 * we want to write a bit pattern XXX1 to Xilinx to enable
656 * the write gate, which will be open for about the next 2ms.
657 */
658 spin_lock_irqsave(&gpio_lock, flags);
659 cpld_modify(1, 1);
660 spin_unlock_irqrestore(&gpio_lock, flags);
661
662 /*
663 * let the ISA bus to catch on...
664 */
665 udelay(25);
666 }
667
668 MSTATIC int __init nwflash_init(void)
669 {
670 int ret = -ENODEV;
671
672 if (machine_is_netwinder()) {
673 int id;
674
675 FLASH_BASE = __ioremap(DC21285_FLASH, KFLASH_SIZE4, 0);
676 if (!FLASH_BASE)
677 goto out;
678
679 id = get_flash_id();
680 printk("Flash ROM driver v.%s, flash device ID 0x%04X, size %d Mb.\n",
681 NWFLASH_VERSION, id, gbFlashSize / (1024 * 1024));
682
683 misc_register(&flash_miscdev);
684
685 ret = 0;
686 }
687 out:
688 return ret;
689 }
690
691 MSTATIC void __exit nwflash_exit(void)
692 {
693 misc_deregister(&flash_miscdev);
694 iounmap((void *)FLASH_BASE);
695 }
696
697 EXPORT_NO_SYMBOLS;
698
699 MODULE_PARM(flashdebug, "i");
700
701 module_init(nwflash_init);
702 module_exit(nwflash_exit);
703
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