cfi_cmdset_0001.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

	}
	if (z > 1) 
		chip->word_write_time++;

	/* Done and happy. */
	DISABLE_VPP(map);
	chip->state = FL_STATUS;
	/* check for lock bit */
	if (status & CMD(0x02)) {
		/* clear status */
		cfi_write(map, CMD(0x50), adr);
		/* put back into read status register mode */
		cfi_write(map, CMD(0x70), adr);
		wake_up(&chip->wq);
		spin_unlock_bh(chip->mutex);
		return -EROFS;
	}
	wake_up(&chip->wq);
	spin_unlock_bh(chip->mutex);
	return 0;
}


static int cfi_intelext_write_words (struct mtd_info *mtd, loff_t to , size_t len, size_t *retlen, const u_char *buf)
{
	struct map_info *map = mtd->priv;
	struct cfi_private *cfi = map->fldrv_priv;
	int ret = 0;
	int chipnum;
	unsigned long ofs;

	*retlen = 0;
	if (!len)
		return 0;

	chipnum = to >> cfi->chipshift;
	ofs = to  - (chipnum << cfi->chipshift);

	/* If it's not bus-aligned, do the first byte write */
	if (ofs & (CFIDEV_BUSWIDTH-1)) {
		unsigned long bus_ofs = ofs & ~(CFIDEV_BUSWIDTH-1);
		int gap = ofs - bus_ofs;
		int i = 0, n = 0;
		u_char tmp_buf[4];
		__u32 datum;

		while (gap--)
			tmp_buf[i++] = 0xff;
		while (len && i < CFIDEV_BUSWIDTH)
			tmp_buf[i++] = buf[n++], len--;
		while (i < CFIDEV_BUSWIDTH)
			tmp_buf[i++] = 0xff;

		if (cfi_buswidth_is_2()) {
			datum = *(__u16*)tmp_buf;
		} else if (cfi_buswidth_is_4()) {
			datum = *(__u32*)tmp_buf;
		} else {
			return -EINVAL;  /* should never happen, but be safe */
		}

		ret = do_write_oneword(map, &cfi->chips[chipnum],
					       bus_ofs, datum);
		if (ret) 
			return ret;
		
		ofs += n;
		buf += n;
		(*retlen) += n;

		if (ofs >> cfi->chipshift) {
			chipnum ++; 
			ofs = 0;
			if (chipnum == cfi->numchips)
				return 0;
		}
	}
	
	while(len >= CFIDEV_BUSWIDTH) {
		__u32 datum;

		if (cfi_buswidth_is_1()) {
			datum = *(__u8*)buf;
		} else if (cfi_buswidth_is_2()) {
			datum = *(__u16*)buf;
		} else if (cfi_buswidth_is_4()) {
			datum = *(__u32*)buf;
		} else {
			return -EINVAL;
		}

		ret = do_write_oneword(map, &cfi->chips[chipnum],
				ofs, datum);
		if (ret)
			return ret;

		ofs += CFIDEV_BUSWIDTH;
		buf += CFIDEV_BUSWIDTH;
		(*retlen) += CFIDEV_BUSWIDTH;
		len -= CFIDEV_BUSWIDTH;

		if (ofs >> cfi->chipshift) {
			chipnum ++; 
			ofs = 0;
			if (chipnum == cfi->numchips)
				return 0;
		}
	}

	if (len & (CFIDEV_BUSWIDTH-1)) {
		int i = 0, n = 0;
		u_char tmp_buf[4];
		__u32 datum;

		while (len--)
			tmp_buf[i++] = buf[n++];
		while (i < CFIDEV_BUSWIDTH)
			tmp_buf[i++] = 0xff;

		if (cfi_buswidth_is_2()) {
			datum = *(__u16*)tmp_buf;
		} else if (cfi_buswidth_is_4()) {
			datum = *(__u32*)tmp_buf;
		} else {
			return -EINVAL;  /* should never happen, but be safe */
		}

		ret = do_write_oneword(map, &cfi->chips[chipnum],
					       ofs, datum);
		if (ret) 
			return ret;
		
		(*retlen) += n;
	}

	return 0;
}


static inline int do_write_buffer(struct map_info *map, struct flchip *chip, 
				  unsigned long adr, const u_char *buf, int len)
{
	struct cfi_private *cfi = map->fldrv_priv;
	__u32 status, status_OK;
	unsigned long cmd_adr, timeo;
	DECLARE_WAITQUEUE(wait, current);
	int wbufsize, z;

	wbufsize = CFIDEV_INTERLEAVE << cfi->cfiq->MaxBufWriteSize;
	adr += chip->start;
	cmd_adr = adr & ~(wbufsize-1);
	
	/* Let's determine this according to the interleave only once */
	status_OK = CMD(0x80);

	timeo = jiffies + HZ;
 retry:
	spin_lock_bh(chip->mutex);

	/* Check that the chip's ready to talk to us.
	 * Later, we can actually think about interrupting it
	 * if it's in FL_ERASING state.
	 * Not just yet, though.
	 */
	switch (chip->state) {
	case FL_READY:
		break;
		
	case FL_CFI_QUERY:
	case FL_JEDEC_QUERY:
		cfi_write(map, CMD(0x70), cmd_adr);
		chip->state = FL_STATUS;

	case FL_STATUS:
		status = cfi_read(map, cmd_adr);
		if ((status & status_OK) == status_OK)
			break;
		/* Urgh. Chip not yet ready to talk to us. */
		if (time_after(jiffies, timeo)) {
			spin_unlock_bh(chip->mutex);
			printk(KERN_ERR "waiting for chip to be ready timed out in buffer write\n");
			return -EIO;
		}

		/* Latency issues. Drop the lock, wait a while and retry */
		spin_unlock_bh(chip->mutex);
		cfi_udelay(1);
		goto retry;

	default:
		/* Stick ourselves on a wait queue to be woken when
		   someone changes the status */
		set_current_state(TASK_UNINTERRUPTIBLE);
		add_wait_queue(&chip->wq, &wait);
		spin_unlock_bh(chip->mutex);
		schedule();
		remove_wait_queue(&chip->wq, &wait);
		timeo = jiffies + HZ;
		goto retry;
	}

	ENABLE_VPP(map);
	cfi_write(map, CMD(0xe8), cmd_adr);
	chip->state = FL_WRITING_TO_BUFFER;

	z = 0;
	for (;;) {
		status = cfi_read(map, cmd_adr);
		if ((status & status_OK) == status_OK)
			break;

		spin_unlock_bh(chip->mutex);
		cfi_udelay(1);
		spin_lock_bh(chip->mutex);

		if (++z > 20) {
			/* Argh. Not ready for write to buffer */
			cfi_write(map, CMD(0x70), cmd_adr);
			chip->state = FL_STATUS;
			DISABLE_VPP(map);
			spin_unlock_bh(chip->mutex);
			printk(KERN_ERR "Chip not ready for buffer write. Xstatus = %x, status = %x\n", status, cfi_read(map, cmd_adr));
			return -EIO;
		}
	}

	/* Write length of data to come */
	cfi_write(map, CMD(len/CFIDEV_BUSWIDTH-1), cmd_adr );

	/* Write data */
	for (z = 0; z < len; z += CFIDEV_BUSWIDTH) {
		if (cfi_buswidth_is_1()) {
			map->write8 (map, *((__u8*)buf)++, adr+z);
		} else if (cfi_buswidth_is_2()) {
			map->write16 (map, *((__u16*)buf)++, adr+z);
		} else if (cfi_buswidth_is_4()) {
			map->write32 (map, *((__u32*)buf)++, adr+z);
		} else {
			DISABLE_VPP(map);
			return -EINVAL;
		}
	}
	/* GO GO GO */
	cfi_write(map, CMD(0xd0), cmd_adr);
	chip->state = FL_WRITING;

	spin_unlock_bh(chip->mutex);
	cfi_udelay(chip->buffer_write_time);
	spin_lock_bh(chip->mutex);

	timeo = jiffies + (HZ/2);
	z = 0;
	for (;;) {
		if (chip->state != FL_WRITING) {
			/* Someone's suspended the write. Sleep */
			set_current_state(TASK_UNINTERRUPTIBLE);
			add_wait_queue(&chip->wq, &wait);
			spin_unlock_bh(chip->mutex);
			schedule();
			remove_wait_queue(&chip->wq, &wait);
			timeo = jiffies + (HZ / 2); /* FIXME */
			spin_lock_bh(chip->mutex);
			continue;
		}

		status = cfi_read(map, cmd_adr);
		if ((status & status_OK) == status_OK)
			break;

		/* OK Still waiting */
		if (time_after(jiffies, timeo)) {
			chip->state = FL_STATUS;
			DISABLE_VPP(map);
			spin_unlock_bh(chip->mutex);
			printk(KERN_ERR "waiting for chip to be ready timed out in bufwrite\n");
			return -EIO;
		}
		
		/* Latency issues. Drop the lock, wait a while and retry */
		spin_unlock_bh(chip->mutex);
		cfi_udelay(1);
		z++;
		spin_lock_bh(chip->mutex);
	}
	if (!z) {
		chip->buffer_write_time--;
		if (!chip->buffer_write_time)
			chip->buffer_write_time++;
	}
	if (z > 1) 
		chip->buffer_write_time++;

	/* Done and happy. */
	DISABLE_VPP(map);
	chip->state = FL_STATUS;
	/* check for lock bit */
	if (status & CMD(0x02)) {
		/* clear status */
		cfi_write(map, CMD(0x50), cmd_adr);
		/* put back into read status register mode */
		cfi_write(map, CMD(0x70), adr);
		wake_up(&chip->wq);
		spin_unlock_bh(chip->mutex);
		return -EROFS;
	}
	wake_up(&chip->wq);
	spin_unlock_bh(chip->mutex);
	return 0;
}

static int cfi_intelext_write_buffers (struct mtd_info *mtd, loff_t to, 
				       size_t len, size_t *retlen, const u_char *buf)
{
	struct map_info *map = mtd->priv;
	struct cfi_private *cfi = map->fldrv_priv;
	int wbufsize = CFIDEV_INTERLEAVE << cfi->cfiq->MaxBufWriteSize;
	int ret = 0;
	int chipnum;
	unsigned long ofs;

	*retlen = 0;
	if (!len)
		return 0;

	chipnum = to >> cfi->chipshift;
	ofs = to  - (chipnum << cfi->chipshift);

	/* If it's not bus-aligned, do the first word write */
	if (ofs & (CFIDEV_BUSWIDTH-1)) {
		size_t local_len = (-ofs)&(CFIDEV_BUSWIDTH-1);
		if (local_len > len)
			local_len = len;
		ret = cfi_intelext_write_words(mtd, to, local_len,
					       retlen, buf);
		if (ret)
			return ret;
		ofs += local_len;
		buf += local_len;
		len -= local_len;

		if (ofs >> cfi->chipshift) {
			chipnum ++;
			ofs = 0;
			if (chipnum == cfi->numchips)
				return 0;
		}
	}

	/* Write buffer is worth it only if more than one word to write... */
	while(len > CFIDEV_BUSWIDTH) {
		/* We must not cross write block boundaries */
		int size = wbufsize - (ofs & (wbufsize-1));

		if (size > len)
			size = len & ~(CFIDEV_BUSWIDTH-1);
		ret = do_write_buffer(map, &cfi->chips[chipnum], 
				      ofs, buf, size);
		if (ret)
			return ret;

		ofs += size;
		buf += size;
		(*retlen) += size;
		len -= size;

		if (ofs >> cfi->chipshift) {
			chipnum ++; 
			ofs = 0;
			if (chipnum == cfi->numchips)
				return 0;
		}
	}

	/* ... and write the remaining bytes */
	if (len > 0) {
		size_t local_retlen;
		ret = cfi_intelext_write_words(mtd, ofs + (chipnum << cfi->chipshift),
					       len, &local_retlen, buf);
		if (ret)
			return ret;
		(*retlen) += local_retlen;
	}

	return 0;
}


static inline int do_erase_oneblock(struct map_info *map, struct flchip *chip, unsigned long adr)
{
	struct cfi_private *cfi = map->fldrv_priv;
	__u32 status, status_OK;
	unsigned long timeo;
	int retries = 3;
	DECLARE_WAITQUEUE(wait, current);
	int ret = 0;

	adr += chip->start;

	/* Let's determine this according to the interleave only once */
	status_OK = CMD(0x80);

	timeo = jiffies + HZ;
retry:
	spin_lock_bh(chip->mutex);

	/* Check that the chip's ready to talk to us. */
	switch (chip->state) {
	case FL_CFI_QUERY:
	case FL_JEDEC_QUERY:
	case FL_READY:
		cfi_write(map, CMD(0x70), adr);
		chip->state = FL_STATUS;

	case FL_STATUS:
		status = cfi_read(map, adr);
		if ((status & status_OK) == status_OK)
			break;
		
		/* Urgh. Chip not yet ready to talk to us. */
		if (time_after(jiffies, timeo)) {
			spin_unlock_bh(chip->mutex);
			printk(KERN_ERR "waiting for chip to be ready timed out in erase\n");
			return -EIO;
		}

		/* Latency issues. Drop the lock, wait a while and retry */
		spin_unlock_bh(chip->mutex);
		cfi_udelay(1);
		goto retry;

	default:
		/* Stick ourselves on a wait queue to be woken when
		   someone changes the status */
		set_current_state(TASK_UNINTERRUPTIBLE);
		add_wait_queue(&chip->wq, &wait);
		spin_unlock_bh(chip->mutex);
		schedule();
		remove_wait_queue(&chip->wq, &wait);
		timeo = jiffies + HZ;
		goto retry;
	}

	ENABLE_VPP(map);
	/* Clear the status register first */
	cfi_write(map, CMD(0x50), adr);

	/* Now erase */
	cfi_write(map, CMD(0x20), adr);
	cfi_write(map, CMD(0xD0), adr);
	chip->state = FL_ERASING;
	
	spin_unlock_bh(chip->mutex);
	schedule_timeout(HZ);
	spin_lock_bh(chip->mutex);

	/* FIXME. Use a timer to check this, and return immediately. */
	/* Once the state machine's known to be working I'll do that */

	timeo = jiffies + (HZ*20);
	for (;;) {
		if (chip->state != FL_ERASING) {
			/* Someone's suspended the erase. Sleep */
			set_current_state(TASK_UNINTERRUPTIBLE);
			add_wait_queue(&chip->wq, &wait);
			spin_unlock_bh(chip->mutex);
			schedule();
			remove_wait_queue(&chip->wq, &wait);
			timeo = jiffies + (HZ*20); /* FIXME */
			spin_lock_bh(chip->mutex);
			continue;
		}

		status = cfi_read(map, adr);
		if ((status & status_OK) == status_OK)
			break;
		
		/* OK Still waiting */
		if (time_after(jiffies, timeo)) {
			cfi_write(map, CMD(0x70), adr);
			chip->state = FL_STATUS;
			printk(KERN_ERR "waiting for erase to complete timed out. Xstatus = %x, status = %x.\n", status, cfi_read(map, adr));
			DISABLE_VPP(map);
			spin_unlock_bh(chip->mutex);
			return -EIO;
		}
		
		/* Latency issues. Drop the lock, wait a while and retry */
		spin_unlock_bh(chip->mutex);
		cfi_udelay(1);
		spin_lock_bh(chip->mutex);
	}
	
	DISABLE_VPP(map);
	ret = 0;

	/* We've broken this before. It doesn't hurt to be safe */
	cfi_write(map, CMD(0x70), adr);
	chip->state = FL_STATUS;
	status = cfi_read(map, adr);

	/* check for lock bit */
	if (status & CMD(0x3a)) {
		unsigned char chipstatus = status;
		if (status != CMD(status & 0xff)) {
			int i;
			for (i = 1; i<CFIDEV_INTERLEAVE; i++) {
				      chipstatus |= status >> (cfi->device_type * 8);
			}
			printk(KERN_WARNING "Status is not identical for all chips: 0x%x. Merging to give 0x%02x\n", status, chipstatus);
		}
		/* Reset the error bits */
		cfi_write(map, CMD(0x50), adr);
		cfi_write(map, CMD(0x70), adr);
		
		if ((chipstatus & 0x30) == 0x30) {
			printk(KERN_NOTICE "Chip reports improper command sequence: status 0x%x\n", status);
			ret = -EIO;
		} else if (chipstatus & 0x02) {
			/* Protection bit set */
			ret = -EROFS;
		} else if (chipstatus & 0x8) {
			/* Voltage */
			printk(KERN_WARNING "Chip reports voltage low on erase: status 0x%x\n", status);
			ret = -EIO;
		} else if (chipstatus & 0x20) {
			if (retries--) {
				printk(KERN_DEBUG "Chip erase failed at 0x%08lx: status 0x%x. Retrying...\n", adr, status);
				timeo = jiffies + HZ;
				chip->state = FL_STATUS;
				spin_unlock_bh(chip->mutex);
				goto retry;
			}
			printk(KERN_DEBUG "Chip erase failed at 0x%08lx: status 0x%x\n", adr, status);
			ret = -EIO;
		}
	}

	wake_up(&chip->wq);
	spin_unlock_bh(chip->mutex);
	return ret;
}