cfi_cmdset_0001.c

来自「linux嵌入式课程实践中的一个关于声卡驱动程序 。」· C语言 代码 · 共 872 行 · 第 1/2 页

		if (ret)
			break;

		*retlen += thislen;
		len -= thislen;
		buf += thislen;
		
		ofs = 0;
		chipnum++;
	}
	return ret;
}

static int cfi_intelext_read_prot_reg (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf, int base_offst, int reg_sz)
{
	struct map_info *map = mtd->priv;
	struct cfi_private *cfi = map->fldrv_priv;
	struct cfi_pri_intelext *extp=cfi->cmdset_priv;
	int ofs_factor = cfi->interleave * cfi->device_type;
	int   count=len;
	struct flchip *chip;
	int chip_num,offst;
	unsigned long timeo;
	DECLARE_WAITQUEUE(wait, current);

	chip=0;
	/* Calculate which chip & protection register offset we need */
	chip_num=((unsigned int)from/reg_sz);
	offst=from-(reg_sz*chip_num)+base_offst;

	while(count){
		
		if(chip_num>=cfi->numchips)
			goto out;

		/* Make sure that the chip is in the right state */

		timeo = jiffies + HZ;
		chip=&cfi->chips[chip_num];
	retry:		
		spin_lock_bh(chip->mutex);
	
		switch (chip->state) {
		case FL_READY:
		case FL_STATUS:
		case FL_CFI_QUERY:
		case FL_JEDEC_QUERY:
			break;
		
		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;
		}
			
		/* Now read the data required from this flash */
       
		cfi_send_gen_cmd(0x90, 0x55,chip->start, map, cfi, cfi->device_type, NULL);
		while(count && ((offst-base_offst)<reg_sz)){
			*buf=map->read8(map,(chip->start+(extp->ProtRegAddr*ofs_factor)+offst));
			buf++;
			offst++;
			count--;
		}
	       
		chip->state=FL_CFI_QUERY;
		spin_unlock_bh(chip->mutex);
		/* Move on to the next chip */
		chip_num++;
		offst=base_offst;
	
	}
	
 out:	
	wake_up(&chip->wq);
	return len-count;
}
	
static int cfi_intelext_read_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
{
	struct map_info *map = mtd->priv;
	struct cfi_private *cfi = map->fldrv_priv;
	struct cfi_pri_intelext *extp=cfi->cmdset_priv;
	int base_offst,reg_sz;
	
	/* Check that we actually have some protection registers */
	if(!(extp->FeatureSupport&64)){
		printk(KERN_WARNING "%s: This flash device has no protection data to read!\n",map->name);
		return 0;
	}

	base_offst=(1<<extp->FactProtRegSize);
	reg_sz=(1<<extp->UserProtRegSize);

	return cfi_intelext_read_prot_reg(mtd, from, len, retlen, buf, base_offst, reg_sz);
}

static int cfi_intelext_read_fact_prot_reg (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
{
	struct map_info *map = mtd->priv;
	struct cfi_private *cfi = map->fldrv_priv;
	struct cfi_pri_intelext *extp=cfi->cmdset_priv;
	int base_offst,reg_sz;
	
	/* Check that we actually have some protection registers */
	if(!(extp->FeatureSupport&64)){
		printk(KERN_WARNING "%s: This flash device has no protection data to read!\n",map->name);
		return 0;
	}

	base_offst=0;
	reg_sz=(1<<extp->FactProtRegSize);

	return cfi_intelext_read_prot_reg(mtd, from, len, retlen, buf, base_offst, reg_sz);
}


static int do_write_oneword(struct map_info *map, struct flchip *chip, unsigned long adr, cfi_word datum)
{
	struct cfi_private *cfi = map->fldrv_priv;
	cfi_word status, status_OK;
	unsigned long timeo;
	DECLARE_WAITQUEUE(wait, current);
	int z;

	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.
	 * 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), 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 read\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(0x40), adr);
	cfi_write(map, datum, adr);
	chip->state = FL_WRITING;

	spin_unlock_bh(chip->mutex);
	cfi_udelay(chip->word_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, 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 word write\n");
			return -EIO;
		}

		/* Latency issues. Drop the lock, wait a while and retry */
		spin_unlock_bh(chip->mutex);
		z++;
		cfi_udelay(1);
		spin_lock_bh(chip->mutex);
	}
	if (!z) {
		chip->word_write_time--;
		if (!chip->word_write_time)
			chip->word_write_time++;
	}
	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[8];
		cfi_word 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 if (cfi_buswidth_is_8()) {
			datum = *(__u64*)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) {
		cfi_word 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 if (cfi_buswidth_is_8()) {
			datum = *(__u64*)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[8];
		cfi_word 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 if (cfi_buswidth_is_8()) {
			datum = *(__u64*)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;
	cfi_word 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:
	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;
	}
	/* We know we're now in FL_STATUS mode, and 'status' is current */
	/*