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v3.1
  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 * 22/05/2001	RMK	- Lock read against write
  8 *			- merge printk level changes (with mods) from Alan Cox.
  9 *			- use *ppos as the file position, not file->f_pos.
 10 *			- fix check for out of range pos and r/w size
 11 *
 12 * Please note that we are tampering with the only flash chip in the
 13 * machine, which contains the bootup code.  We therefore have the
 14 * power to convert these machines into doorstops...
 15 */
 16
 17#include <linux/module.h>
 18#include <linux/types.h>
 19#include <linux/fs.h>
 20#include <linux/errno.h>
 21#include <linux/mm.h>
 22#include <linux/delay.h>
 23#include <linux/proc_fs.h>
 24#include <linux/miscdevice.h>
 25#include <linux/spinlock.h>
 26#include <linux/rwsem.h>
 27#include <linux/init.h>
 28#include <linux/mutex.h>
 29#include <linux/jiffies.h>
 30
 31#include <asm/hardware/dec21285.h>
 32#include <asm/io.h>
 33#include <asm/leds.h>
 34#include <asm/mach-types.h>
 35#include <asm/system.h>
 36#include <asm/uaccess.h>
 37
 38/*****************************************************************************/
 39#include <asm/nwflash.h>
 40
 41#define	NWFLASH_VERSION "6.4"
 42
 43static DEFINE_MUTEX(flash_mutex);
 44static void kick_open(void);
 45static int get_flash_id(void);
 46static int erase_block(int nBlock);
 47static int write_block(unsigned long p, const char __user *buf, int count);
 48
 49#define KFLASH_SIZE	1024*1024	//1 Meg
 50#define KFLASH_SIZE4	4*1024*1024	//4 Meg
 51#define KFLASH_ID	0x89A6		//Intel flash
 52#define KFLASH_ID4	0xB0D4		//Intel flash 4Meg
 53
 54static int flashdebug;		//if set - we will display progress msgs
 55
 56static int gbWriteEnable;
 57static int gbWriteBase64Enable;
 58static volatile unsigned char *FLASH_BASE;
 59static int gbFlashSize = KFLASH_SIZE;
 60static DEFINE_MUTEX(nwflash_mutex);
 61
 62static int get_flash_id(void)
 63{
 64	volatile unsigned int c1, c2;
 65
 66	/*
 67	 * try to get flash chip ID
 68	 */
 69	kick_open();
 70	c2 = inb(0x80);
 71	*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x90;
 72	udelay(15);
 73	c1 = *(volatile unsigned char *) FLASH_BASE;
 74	c2 = inb(0x80);
 75
 76	/*
 77	 * on 4 Meg flash the second byte is actually at offset 2...
 78	 */
 79	if (c1 == 0xB0)
 80		c2 = *(volatile unsigned char *) (FLASH_BASE + 2);
 81	else
 82		c2 = *(volatile unsigned char *) (FLASH_BASE + 1);
 83
 84	c2 += (c1 << 8);
 85
 86	/*
 87	 * set it back to read mode
 88	 */
 89	*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0xFF;
 90
 91	if (c2 == KFLASH_ID4)
 92		gbFlashSize = KFLASH_SIZE4;
 93
 94	return c2;
 95}
 96
 97static long flash_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
 98{
 99	mutex_lock(&flash_mutex);
100	switch (cmd) {
101	case CMD_WRITE_DISABLE:
102		gbWriteBase64Enable = 0;
103		gbWriteEnable = 0;
104		break;
105
106	case CMD_WRITE_ENABLE:
107		gbWriteEnable = 1;
108		break;
109
110	case CMD_WRITE_BASE64K_ENABLE:
111		gbWriteBase64Enable = 1;
112		break;
113
114	default:
115		gbWriteBase64Enable = 0;
116		gbWriteEnable = 0;
117		mutex_unlock(&flash_mutex);
118		return -EINVAL;
119	}
120	mutex_unlock(&flash_mutex);
121	return 0;
122}
123
124static ssize_t flash_read(struct file *file, char __user *buf, size_t size,
125			  loff_t *ppos)
126{
127	ssize_t ret;
128
129	if (flashdebug)
130		printk(KERN_DEBUG "flash_read: flash_read: offset=0x%llx, "
131		       "buffer=%p, count=0x%zx.\n", *ppos, buf, size);
132	/*
133	 * We now lock against reads and writes. --rmk
134	 */
135	if (mutex_lock_interruptible(&nwflash_mutex))
136		return -ERESTARTSYS;
137
138	ret = simple_read_from_buffer(buf, size, ppos, (void *)FLASH_BASE, gbFlashSize);
139	mutex_unlock(&nwflash_mutex);
140
141	return ret;
142}
143
144static ssize_t flash_write(struct file *file, const char __user *buf,
145			   size_t size, loff_t * ppos)
146{
147	unsigned long p = *ppos;
148	unsigned int count = size;
149	int written;
150	int nBlock, temp, rc;
151	int i, j;
152
153	if (flashdebug)
154		printk("flash_write: offset=0x%lX, buffer=0x%p, count=0x%X.\n",
155		       p, buf, count);
156
157	if (!gbWriteEnable)
158		return -EINVAL;
159
160	if (p < 64 * 1024 && (!gbWriteBase64Enable))
161		return -EINVAL;
162
163	/*
164	 * check for out of range pos or count
165	 */
166	if (p >= gbFlashSize)
167		return count ? -ENXIO : 0;
168
169	if (count > gbFlashSize - p)
170		count = gbFlashSize - p;
171			
172	if (!access_ok(VERIFY_READ, buf, count))
173		return -EFAULT;
174
175	/*
176	 * We now lock against reads and writes. --rmk
177	 */
178	if (mutex_lock_interruptible(&nwflash_mutex))
179		return -ERESTARTSYS;
180
181	written = 0;
182
183	leds_event(led_claim);
184	leds_event(led_green_on);
185
186	nBlock = (int) p >> 16;	//block # of 64K bytes
187
188	/*
189	 * # of 64K blocks to erase and write
190	 */
191	temp = ((int) (p + count) >> 16) - nBlock + 1;
192
193	/*
194	 * write ends at exactly 64k boundary?
195	 */
196	if (((int) (p + count) & 0xFFFF) == 0)
197		temp -= 1;
198
199	if (flashdebug)
200		printk(KERN_DEBUG "flash_write: writing %d block(s) "
201			"starting at %d.\n", temp, nBlock);
202
203	for (; temp; temp--, nBlock++) {
204		if (flashdebug)
205			printk(KERN_DEBUG "flash_write: erasing block %d.\n", nBlock);
206
207		/*
208		 * first we have to erase the block(s), where we will write...
209		 */
210		i = 0;
211		j = 0;
212	  RetryBlock:
213		do {
214			rc = erase_block(nBlock);
215			i++;
216		} while (rc && i < 10);
217
218		if (rc) {
219			printk(KERN_ERR "flash_write: erase error %x\n", rc);
220			break;
221		}
222		if (flashdebug)
223			printk(KERN_DEBUG "flash_write: writing offset %lX, "
224			       "from buf %p, bytes left %X.\n", p, buf,
225			       count - written);
226
227		/*
228		 * write_block will limit write to space left in this block
229		 */
230		rc = write_block(p, buf, count - written);
231		j++;
232
233		/*
234		 * if somehow write verify failed? Can't happen??
235		 */
236		if (!rc) {
237			/*
238			 * retry up to 10 times
239			 */
240			if (j < 10)
241				goto RetryBlock;
242			else
243				/*
244				 * else quit with error...
245				 */
246				rc = -1;
247
248		}
249		if (rc < 0) {
250			printk(KERN_ERR "flash_write: write error %X\n", rc);
251			break;
252		}
253		p += rc;
254		buf += rc;
255		written += rc;
256		*ppos += rc;
257
258		if (flashdebug)
259			printk(KERN_DEBUG "flash_write: written 0x%X bytes OK.\n", written);
260	}
261
262	/*
263	 * restore reg on exit
264	 */
265	leds_event(led_release);
266
267	mutex_unlock(&nwflash_mutex);
268
269	return written;
270}
271
272
273/*
274 * The memory devices use the full 32/64 bits of the offset, and so we cannot
275 * check against negative addresses: they are ok. The return value is weird,
276 * though, in that case (0).
277 *
278 * also note that seeking relative to the "end of file" isn't supported:
279 * it has no meaning, so it returns -EINVAL.
280 */
281static loff_t flash_llseek(struct file *file, loff_t offset, int orig)
282{
283	loff_t ret;
284
285	mutex_lock(&flash_mutex);
286	if (flashdebug)
287		printk(KERN_DEBUG "flash_llseek: offset=0x%X, orig=0x%X.\n",
288		       (unsigned int) offset, orig);
289
290	switch (orig) {
291	case 0:
292		if (offset < 0) {
293			ret = -EINVAL;
294			break;
295		}
296
297		if ((unsigned int) offset > gbFlashSize) {
298			ret = -EINVAL;
299			break;
300		}
301
302		file->f_pos = (unsigned int) offset;
303		ret = file->f_pos;
304		break;
305	case 1:
306		if ((file->f_pos + offset) > gbFlashSize) {
307			ret = -EINVAL;
308			break;
309		}
310		if ((file->f_pos + offset) < 0) {
311			ret = -EINVAL;
312			break;
313		}
314		file->f_pos += offset;
315		ret = file->f_pos;
316		break;
317	default:
318		ret = -EINVAL;
319	}
320	mutex_unlock(&flash_mutex);
321	return ret;
322}
323
324
325/*
326 * assume that main Write routine did the parameter checking...
327 * so just go ahead and erase, what requested!
328 */
329
330static int erase_block(int nBlock)
331{
332	volatile unsigned int c1;
333	volatile unsigned char *pWritePtr;
334	unsigned long timeout;
335	int temp, temp1;
336
337	/*
338	 * orange LED == erase
339	 */
340	leds_event(led_amber_on);
341
342	/*
343	 * reset footbridge to the correct offset 0 (...0..3)
344	 */
345	*CSR_ROMWRITEREG = 0;
346
347	/*
348	 * dummy ROM read
349	 */
350	c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
351
352	kick_open();
353	/*
354	 * reset status if old errors
355	 */
356	*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
357
358	/*
359	 * erase a block...
360	 * aim at the middle of a current block...
361	 */
362	pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + 0x8000 + (nBlock << 16)));
363	/*
364	 * dummy read
365	 */
366	c1 = *pWritePtr;
367
368	kick_open();
369	/*
370	 * erase
371	 */
372	*(volatile unsigned char *) pWritePtr = 0x20;
373
374	/*
375	 * confirm
376	 */
377	*(volatile unsigned char *) pWritePtr = 0xD0;
378
379	/*
380	 * wait 10 ms
381	 */
382	msleep(10);
383
384	/*
385	 * wait while erasing in process (up to 10 sec)
386	 */
387	timeout = jiffies + 10 * HZ;
388	c1 = 0;
389	while (!(c1 & 0x80) && time_before(jiffies, timeout)) {
390		msleep(10);
391		/*
392		 * read any address
393		 */
394		c1 = *(volatile unsigned char *) (pWritePtr);
395		//              printk("Flash_erase: status=%X.\n",c1);
396	}
397
398	/*
399	 * set flash for normal read access
400	 */
401	kick_open();
402//      *(volatile unsigned char*)(FLASH_BASE+0x8000) = 0xFF;
403	*(volatile unsigned char *) pWritePtr = 0xFF;	//back to normal operation
404
405	/*
406	 * check if erase errors were reported
407	 */
408	if (c1 & 0x20) {
409		printk(KERN_ERR "flash_erase: err at %p\n", pWritePtr);
410
411		/*
412		 * reset error
413		 */
414		*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
415		return -2;
416	}
417
418	/*
419	 * just to make sure - verify if erased OK...
420	 */
421	msleep(10);
422
423	pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + (nBlock << 16)));
424
425	for (temp = 0; temp < 16 * 1024; temp++, pWritePtr += 4) {
426		if ((temp1 = *(volatile unsigned int *) pWritePtr) != 0xFFFFFFFF) {
427			printk(KERN_ERR "flash_erase: verify err at %p = %X\n",
428			       pWritePtr, temp1);
429			return -1;
430		}
431	}
432
433	return 0;
434
435}
436
437/*
438 * write_block will limit number of bytes written to the space in this block
439 */
440static int write_block(unsigned long p, const char __user *buf, int count)
441{
442	volatile unsigned int c1;
443	volatile unsigned int c2;
444	unsigned char *pWritePtr;
445	unsigned int uAddress;
446	unsigned int offset;
447	unsigned long timeout;
448	unsigned long timeout1;
449
450	/*
451	 * red LED == write
452	 */
453	leds_event(led_amber_off);
454	leds_event(led_red_on);
455
456	pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + p));
457
458	/*
459	 * check if write will end in this block....
460	 */
461	offset = p & 0xFFFF;
462
463	if (offset + count > 0x10000)
464		count = 0x10000 - offset;
465
466	/*
467	 * wait up to 30 sec for this block
468	 */
469	timeout = jiffies + 30 * HZ;
470
471	for (offset = 0; offset < count; offset++, pWritePtr++) {
472		uAddress = (unsigned int) pWritePtr;
473		uAddress &= 0xFFFFFFFC;
474		if (__get_user(c2, buf + offset))
475			return -EFAULT;
476
477	  WriteRetry:
478	  	/*
479	  	 * dummy read
480	  	 */
481		c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
482
483		/*
484		 * kick open the write gate
485		 */
486		kick_open();
487
488		/*
489		 * program footbridge to the correct offset...0..3
490		 */
491		*CSR_ROMWRITEREG = (unsigned int) pWritePtr & 3;
492
493		/*
494		 * write cmd
495		 */
496		*(volatile unsigned char *) (uAddress) = 0x40;
497
498		/*
499		 * data to write
500		 */
501		*(volatile unsigned char *) (uAddress) = c2;
502
503		/*
504		 * get status
505		 */
506		*(volatile unsigned char *) (FLASH_BASE + 0x10000) = 0x70;
507
508		c1 = 0;
509
510		/*
511		 * wait up to 1 sec for this byte
512		 */
513		timeout1 = jiffies + 1 * HZ;
514
515		/*
516		 * while not ready...
517		 */
518		while (!(c1 & 0x80) && time_before(jiffies, timeout1))
519			c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
520
521		/*
522		 * if timeout getting status
523		 */
524		if (time_after_eq(jiffies, timeout1)) {
525			kick_open();
526			/*
527			 * reset err
528			 */
529			*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
530
531			goto WriteRetry;
532		}
533		/*
534		 * switch on read access, as a default flash operation mode
535		 */
536		kick_open();
537		/*
538		 * read access
539		 */
540		*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0xFF;
541
542		/*
543		 * if hardware reports an error writing, and not timeout - 
544		 * reset the chip and retry
545		 */
546		if (c1 & 0x10) {
547			kick_open();
548			/*
549			 * reset err
550			 */
551			*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
552
553			/*
554			 * before timeout?
555			 */
556			if (time_before(jiffies, timeout)) {
557				if (flashdebug)
558					printk(KERN_DEBUG "write_block: Retrying write at 0x%X)n",
559					       pWritePtr - FLASH_BASE);
560
561				/*
562				 * no LED == waiting
563				 */
564				leds_event(led_amber_off);
565				/*
566				 * wait couple ms
567				 */
568				msleep(10);
569				/*
570				 * red LED == write
571				 */
572				leds_event(led_red_on);
573
574				goto WriteRetry;
575			} else {
576				printk(KERN_ERR "write_block: timeout at 0x%X\n",
577				       pWritePtr - FLASH_BASE);
578				/*
579				 * return error -2
580				 */
581				return -2;
582
583			}
584		}
585	}
586
587	/*
588	 * green LED == read/verify
589	 */
590	leds_event(led_amber_off);
591	leds_event(led_green_on);
592
593	msleep(10);
594
595	pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + p));
596
597	for (offset = 0; offset < count; offset++) {
598		char c, c1;
599		if (__get_user(c, buf))
600			return -EFAULT;
601		buf++;
602		if ((c1 = *pWritePtr++) != c) {
603			printk(KERN_ERR "write_block: verify error at 0x%X (%02X!=%02X)\n",
604			       pWritePtr - FLASH_BASE, c1, c);
605			return 0;
606		}
607	}
608
609	return count;
610}
611
612
613static void kick_open(void)
614{
615	unsigned long flags;
616
617	/*
618	 * we want to write a bit pattern XXX1 to Xilinx to enable
619	 * the write gate, which will be open for about the next 2ms.
620	 */
621	spin_lock_irqsave(&nw_gpio_lock, flags);
622	nw_cpld_modify(CPLD_FLASH_WR_ENABLE, CPLD_FLASH_WR_ENABLE);
623	spin_unlock_irqrestore(&nw_gpio_lock, flags);
624
625	/*
626	 * let the ISA bus to catch on...
627	 */
628	udelay(25);
629}
630
631static const struct file_operations flash_fops =
632{
633	.owner		= THIS_MODULE,
634	.llseek		= flash_llseek,
635	.read		= flash_read,
636	.write		= flash_write,
637	.unlocked_ioctl	= flash_ioctl,
638};
639
640static struct miscdevice flash_miscdev =
641{
642	FLASH_MINOR,
643	"nwflash",
644	&flash_fops
645};
646
647static int __init nwflash_init(void)
648{
649	int ret = -ENODEV;
650
651	if (machine_is_netwinder()) {
652		int id;
653
654		FLASH_BASE = ioremap(DC21285_FLASH, KFLASH_SIZE4);
655		if (!FLASH_BASE)
656			goto out;
657
658		id = get_flash_id();
659		if ((id != KFLASH_ID) && (id != KFLASH_ID4)) {
660			ret = -ENXIO;
661			iounmap((void *)FLASH_BASE);
662			printk("Flash: incorrect ID 0x%04X.\n", id);
663			goto out;
664		}
665
666		printk("Flash ROM driver v.%s, flash device ID 0x%04X, size %d Mb.\n",
667		       NWFLASH_VERSION, id, gbFlashSize / (1024 * 1024));
668
669		ret = misc_register(&flash_miscdev);
670		if (ret < 0) {
671			iounmap((void *)FLASH_BASE);
672		}
673	}
674out:
675	return ret;
676}
677
678static void __exit nwflash_exit(void)
679{
680	misc_deregister(&flash_miscdev);
681	iounmap((void *)FLASH_BASE);
682}
683
684MODULE_LICENSE("GPL");
685
686module_param(flashdebug, bool, 0644);
687
688module_init(nwflash_init);
689module_exit(nwflash_exit);
v4.6
  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 * 22/05/2001	RMK	- Lock read against write
  8 *			- merge printk level changes (with mods) from Alan Cox.
  9 *			- use *ppos as the file position, not file->f_pos.
 10 *			- fix check for out of range pos and r/w size
 11 *
 12 * Please note that we are tampering with the only flash chip in the
 13 * machine, which contains the bootup code.  We therefore have the
 14 * power to convert these machines into doorstops...
 15 */
 16
 17#include <linux/module.h>
 18#include <linux/types.h>
 19#include <linux/fs.h>
 20#include <linux/errno.h>
 21#include <linux/mm.h>
 22#include <linux/delay.h>
 23#include <linux/proc_fs.h>
 24#include <linux/miscdevice.h>
 25#include <linux/spinlock.h>
 26#include <linux/rwsem.h>
 27#include <linux/init.h>
 28#include <linux/mutex.h>
 29#include <linux/jiffies.h>
 30
 31#include <asm/hardware/dec21285.h>
 32#include <asm/io.h>
 
 33#include <asm/mach-types.h>
 
 34#include <asm/uaccess.h>
 35
 36/*****************************************************************************/
 37#include <asm/nwflash.h>
 38
 39#define	NWFLASH_VERSION "6.4"
 40
 41static DEFINE_MUTEX(flash_mutex);
 42static void kick_open(void);
 43static int get_flash_id(void);
 44static int erase_block(int nBlock);
 45static int write_block(unsigned long p, const char __user *buf, int count);
 46
 47#define KFLASH_SIZE	1024*1024	//1 Meg
 48#define KFLASH_SIZE4	4*1024*1024	//4 Meg
 49#define KFLASH_ID	0x89A6		//Intel flash
 50#define KFLASH_ID4	0xB0D4		//Intel flash 4Meg
 51
 52static bool flashdebug;		//if set - we will display progress msgs
 53
 54static int gbWriteEnable;
 55static int gbWriteBase64Enable;
 56static volatile unsigned char *FLASH_BASE;
 57static int gbFlashSize = KFLASH_SIZE;
 58static DEFINE_MUTEX(nwflash_mutex);
 59
 60static int get_flash_id(void)
 61{
 62	volatile unsigned int c1, c2;
 63
 64	/*
 65	 * try to get flash chip ID
 66	 */
 67	kick_open();
 68	c2 = inb(0x80);
 69	*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x90;
 70	udelay(15);
 71	c1 = *(volatile unsigned char *) FLASH_BASE;
 72	c2 = inb(0x80);
 73
 74	/*
 75	 * on 4 Meg flash the second byte is actually at offset 2...
 76	 */
 77	if (c1 == 0xB0)
 78		c2 = *(volatile unsigned char *) (FLASH_BASE + 2);
 79	else
 80		c2 = *(volatile unsigned char *) (FLASH_BASE + 1);
 81
 82	c2 += (c1 << 8);
 83
 84	/*
 85	 * set it back to read mode
 86	 */
 87	*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0xFF;
 88
 89	if (c2 == KFLASH_ID4)
 90		gbFlashSize = KFLASH_SIZE4;
 91
 92	return c2;
 93}
 94
 95static long flash_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
 96{
 97	mutex_lock(&flash_mutex);
 98	switch (cmd) {
 99	case CMD_WRITE_DISABLE:
100		gbWriteBase64Enable = 0;
101		gbWriteEnable = 0;
102		break;
103
104	case CMD_WRITE_ENABLE:
105		gbWriteEnable = 1;
106		break;
107
108	case CMD_WRITE_BASE64K_ENABLE:
109		gbWriteBase64Enable = 1;
110		break;
111
112	default:
113		gbWriteBase64Enable = 0;
114		gbWriteEnable = 0;
115		mutex_unlock(&flash_mutex);
116		return -EINVAL;
117	}
118	mutex_unlock(&flash_mutex);
119	return 0;
120}
121
122static ssize_t flash_read(struct file *file, char __user *buf, size_t size,
123			  loff_t *ppos)
124{
125	ssize_t ret;
126
127	if (flashdebug)
128		printk(KERN_DEBUG "flash_read: flash_read: offset=0x%llx, "
129		       "buffer=%p, count=0x%zx.\n", *ppos, buf, size);
130	/*
131	 * We now lock against reads and writes. --rmk
132	 */
133	if (mutex_lock_interruptible(&nwflash_mutex))
134		return -ERESTARTSYS;
135
136	ret = simple_read_from_buffer(buf, size, ppos, (void *)FLASH_BASE, gbFlashSize);
137	mutex_unlock(&nwflash_mutex);
138
139	return ret;
140}
141
142static ssize_t flash_write(struct file *file, const char __user *buf,
143			   size_t size, loff_t * ppos)
144{
145	unsigned long p = *ppos;
146	unsigned int count = size;
147	int written;
148	int nBlock, temp, rc;
149	int i, j;
150
151	if (flashdebug)
152		printk("flash_write: offset=0x%lX, buffer=0x%p, count=0x%X.\n",
153		       p, buf, count);
154
155	if (!gbWriteEnable)
156		return -EINVAL;
157
158	if (p < 64 * 1024 && (!gbWriteBase64Enable))
159		return -EINVAL;
160
161	/*
162	 * check for out of range pos or count
163	 */
164	if (p >= gbFlashSize)
165		return count ? -ENXIO : 0;
166
167	if (count > gbFlashSize - p)
168		count = gbFlashSize - p;
169			
170	if (!access_ok(VERIFY_READ, buf, count))
171		return -EFAULT;
172
173	/*
174	 * We now lock against reads and writes. --rmk
175	 */
176	if (mutex_lock_interruptible(&nwflash_mutex))
177		return -ERESTARTSYS;
178
179	written = 0;
180
 
 
 
181	nBlock = (int) p >> 16;	//block # of 64K bytes
182
183	/*
184	 * # of 64K blocks to erase and write
185	 */
186	temp = ((int) (p + count) >> 16) - nBlock + 1;
187
188	/*
189	 * write ends at exactly 64k boundary?
190	 */
191	if (((int) (p + count) & 0xFFFF) == 0)
192		temp -= 1;
193
194	if (flashdebug)
195		printk(KERN_DEBUG "flash_write: writing %d block(s) "
196			"starting at %d.\n", temp, nBlock);
197
198	for (; temp; temp--, nBlock++) {
199		if (flashdebug)
200			printk(KERN_DEBUG "flash_write: erasing block %d.\n", nBlock);
201
202		/*
203		 * first we have to erase the block(s), where we will write...
204		 */
205		i = 0;
206		j = 0;
207	  RetryBlock:
208		do {
209			rc = erase_block(nBlock);
210			i++;
211		} while (rc && i < 10);
212
213		if (rc) {
214			printk(KERN_ERR "flash_write: erase error %x\n", rc);
215			break;
216		}
217		if (flashdebug)
218			printk(KERN_DEBUG "flash_write: writing offset %lX, "
219			       "from buf %p, bytes left %X.\n", p, buf,
220			       count - written);
221
222		/*
223		 * write_block will limit write to space left in this block
224		 */
225		rc = write_block(p, buf, count - written);
226		j++;
227
228		/*
229		 * if somehow write verify failed? Can't happen??
230		 */
231		if (!rc) {
232			/*
233			 * retry up to 10 times
234			 */
235			if (j < 10)
236				goto RetryBlock;
237			else
238				/*
239				 * else quit with error...
240				 */
241				rc = -1;
242
243		}
244		if (rc < 0) {
245			printk(KERN_ERR "flash_write: write error %X\n", rc);
246			break;
247		}
248		p += rc;
249		buf += rc;
250		written += rc;
251		*ppos += rc;
252
253		if (flashdebug)
254			printk(KERN_DEBUG "flash_write: written 0x%X bytes OK.\n", written);
255	}
256
 
 
 
 
 
257	mutex_unlock(&nwflash_mutex);
258
259	return written;
260}
261
262
263/*
264 * The memory devices use the full 32/64 bits of the offset, and so we cannot
265 * check against negative addresses: they are ok. The return value is weird,
266 * though, in that case (0).
267 *
268 * also note that seeking relative to the "end of file" isn't supported:
269 * it has no meaning, so it returns -EINVAL.
270 */
271static loff_t flash_llseek(struct file *file, loff_t offset, int orig)
272{
273	loff_t ret;
274
275	mutex_lock(&flash_mutex);
276	if (flashdebug)
277		printk(KERN_DEBUG "flash_llseek: offset=0x%X, orig=0x%X.\n",
278		       (unsigned int) offset, orig);
279
280	ret = no_seek_end_llseek_size(file, offset, orig, gbFlashSize);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
281	mutex_unlock(&flash_mutex);
282	return ret;
283}
284
285
286/*
287 * assume that main Write routine did the parameter checking...
288 * so just go ahead and erase, what requested!
289 */
290
291static int erase_block(int nBlock)
292{
293	volatile unsigned int c1;
294	volatile unsigned char *pWritePtr;
295	unsigned long timeout;
296	int temp, temp1;
297
298	/*
 
 
 
 
 
299	 * reset footbridge to the correct offset 0 (...0..3)
300	 */
301	*CSR_ROMWRITEREG = 0;
302
303	/*
304	 * dummy ROM read
305	 */
306	c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
307
308	kick_open();
309	/*
310	 * reset status if old errors
311	 */
312	*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
313
314	/*
315	 * erase a block...
316	 * aim at the middle of a current block...
317	 */
318	pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + 0x8000 + (nBlock << 16)));
319	/*
320	 * dummy read
321	 */
322	c1 = *pWritePtr;
323
324	kick_open();
325	/*
326	 * erase
327	 */
328	*(volatile unsigned char *) pWritePtr = 0x20;
329
330	/*
331	 * confirm
332	 */
333	*(volatile unsigned char *) pWritePtr = 0xD0;
334
335	/*
336	 * wait 10 ms
337	 */
338	msleep(10);
339
340	/*
341	 * wait while erasing in process (up to 10 sec)
342	 */
343	timeout = jiffies + 10 * HZ;
344	c1 = 0;
345	while (!(c1 & 0x80) && time_before(jiffies, timeout)) {
346		msleep(10);
347		/*
348		 * read any address
349		 */
350		c1 = *(volatile unsigned char *) (pWritePtr);
351		//              printk("Flash_erase: status=%X.\n",c1);
352	}
353
354	/*
355	 * set flash for normal read access
356	 */
357	kick_open();
358//      *(volatile unsigned char*)(FLASH_BASE+0x8000) = 0xFF;
359	*(volatile unsigned char *) pWritePtr = 0xFF;	//back to normal operation
360
361	/*
362	 * check if erase errors were reported
363	 */
364	if (c1 & 0x20) {
365		printk(KERN_ERR "flash_erase: err at %p\n", pWritePtr);
366
367		/*
368		 * reset error
369		 */
370		*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
371		return -2;
372	}
373
374	/*
375	 * just to make sure - verify if erased OK...
376	 */
377	msleep(10);
378
379	pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + (nBlock << 16)));
380
381	for (temp = 0; temp < 16 * 1024; temp++, pWritePtr += 4) {
382		if ((temp1 = *(volatile unsigned int *) pWritePtr) != 0xFFFFFFFF) {
383			printk(KERN_ERR "flash_erase: verify err at %p = %X\n",
384			       pWritePtr, temp1);
385			return -1;
386		}
387	}
388
389	return 0;
390
391}
392
393/*
394 * write_block will limit number of bytes written to the space in this block
395 */
396static int write_block(unsigned long p, const char __user *buf, int count)
397{
398	volatile unsigned int c1;
399	volatile unsigned int c2;
400	unsigned char *pWritePtr;
401	unsigned int uAddress;
402	unsigned int offset;
403	unsigned long timeout;
404	unsigned long timeout1;
405
 
 
 
 
 
 
406	pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + p));
407
408	/*
409	 * check if write will end in this block....
410	 */
411	offset = p & 0xFFFF;
412
413	if (offset + count > 0x10000)
414		count = 0x10000 - offset;
415
416	/*
417	 * wait up to 30 sec for this block
418	 */
419	timeout = jiffies + 30 * HZ;
420
421	for (offset = 0; offset < count; offset++, pWritePtr++) {
422		uAddress = (unsigned int) pWritePtr;
423		uAddress &= 0xFFFFFFFC;
424		if (__get_user(c2, buf + offset))
425			return -EFAULT;
426
427	  WriteRetry:
428	  	/*
429	  	 * dummy read
430	  	 */
431		c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
432
433		/*
434		 * kick open the write gate
435		 */
436		kick_open();
437
438		/*
439		 * program footbridge to the correct offset...0..3
440		 */
441		*CSR_ROMWRITEREG = (unsigned int) pWritePtr & 3;
442
443		/*
444		 * write cmd
445		 */
446		*(volatile unsigned char *) (uAddress) = 0x40;
447
448		/*
449		 * data to write
450		 */
451		*(volatile unsigned char *) (uAddress) = c2;
452
453		/*
454		 * get status
455		 */
456		*(volatile unsigned char *) (FLASH_BASE + 0x10000) = 0x70;
457
458		c1 = 0;
459
460		/*
461		 * wait up to 1 sec for this byte
462		 */
463		timeout1 = jiffies + 1 * HZ;
464
465		/*
466		 * while not ready...
467		 */
468		while (!(c1 & 0x80) && time_before(jiffies, timeout1))
469			c1 = *(volatile unsigned char *) (FLASH_BASE + 0x8000);
470
471		/*
472		 * if timeout getting status
473		 */
474		if (time_after_eq(jiffies, timeout1)) {
475			kick_open();
476			/*
477			 * reset err
478			 */
479			*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
480
481			goto WriteRetry;
482		}
483		/*
484		 * switch on read access, as a default flash operation mode
485		 */
486		kick_open();
487		/*
488		 * read access
489		 */
490		*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0xFF;
491
492		/*
493		 * if hardware reports an error writing, and not timeout - 
494		 * reset the chip and retry
495		 */
496		if (c1 & 0x10) {
497			kick_open();
498			/*
499			 * reset err
500			 */
501			*(volatile unsigned char *) (FLASH_BASE + 0x8000) = 0x50;
502
503			/*
504			 * before timeout?
505			 */
506			if (time_before(jiffies, timeout)) {
507				if (flashdebug)
508					printk(KERN_DEBUG "write_block: Retrying write at 0x%X)n",
509					       pWritePtr - FLASH_BASE);
510
511				/*
 
 
 
 
512				 * wait couple ms
513				 */
514				msleep(10);
 
 
 
 
515
516				goto WriteRetry;
517			} else {
518				printk(KERN_ERR "write_block: timeout at 0x%X\n",
519				       pWritePtr - FLASH_BASE);
520				/*
521				 * return error -2
522				 */
523				return -2;
524
525			}
526		}
527	}
528
 
 
 
 
 
 
529	msleep(10);
530
531	pWritePtr = (unsigned char *) ((unsigned int) (FLASH_BASE + p));
532
533	for (offset = 0; offset < count; offset++) {
534		char c, c1;
535		if (__get_user(c, buf))
536			return -EFAULT;
537		buf++;
538		if ((c1 = *pWritePtr++) != c) {
539			printk(KERN_ERR "write_block: verify error at 0x%X (%02X!=%02X)\n",
540			       pWritePtr - FLASH_BASE, c1, c);
541			return 0;
542		}
543	}
544
545	return count;
546}
547
548
549static void kick_open(void)
550{
551	unsigned long flags;
552
553	/*
554	 * we want to write a bit pattern XXX1 to Xilinx to enable
555	 * the write gate, which will be open for about the next 2ms.
556	 */
557	raw_spin_lock_irqsave(&nw_gpio_lock, flags);
558	nw_cpld_modify(CPLD_FLASH_WR_ENABLE, CPLD_FLASH_WR_ENABLE);
559	raw_spin_unlock_irqrestore(&nw_gpio_lock, flags);
560
561	/*
562	 * let the ISA bus to catch on...
563	 */
564	udelay(25);
565}
566
567static const struct file_operations flash_fops =
568{
569	.owner		= THIS_MODULE,
570	.llseek		= flash_llseek,
571	.read		= flash_read,
572	.write		= flash_write,
573	.unlocked_ioctl	= flash_ioctl,
574};
575
576static struct miscdevice flash_miscdev =
577{
578	FLASH_MINOR,
579	"nwflash",
580	&flash_fops
581};
582
583static int __init nwflash_init(void)
584{
585	int ret = -ENODEV;
586
587	if (machine_is_netwinder()) {
588		int id;
589
590		FLASH_BASE = ioremap(DC21285_FLASH, KFLASH_SIZE4);
591		if (!FLASH_BASE)
592			goto out;
593
594		id = get_flash_id();
595		if ((id != KFLASH_ID) && (id != KFLASH_ID4)) {
596			ret = -ENXIO;
597			iounmap((void *)FLASH_BASE);
598			printk("Flash: incorrect ID 0x%04X.\n", id);
599			goto out;
600		}
601
602		printk("Flash ROM driver v.%s, flash device ID 0x%04X, size %d Mb.\n",
603		       NWFLASH_VERSION, id, gbFlashSize / (1024 * 1024));
604
605		ret = misc_register(&flash_miscdev);
606		if (ret < 0) {
607			iounmap((void *)FLASH_BASE);
608		}
609	}
610out:
611	return ret;
612}
613
614static void __exit nwflash_exit(void)
615{
616	misc_deregister(&flash_miscdev);
617	iounmap((void *)FLASH_BASE);
618}
619
620MODULE_LICENSE("GPL");
621
622module_param(flashdebug, bool, 0644);
623
624module_init(nwflash_init);
625module_exit(nwflash_exit);