cfi_cmdset_0020.c

基于linux-2.6.28的mtd驱动

/*
 * Common Flash Interface support:
 *   ST Advanced Architecture Command Set (ID 0x0020)
 *
 * (C) 2000 Red Hat. GPL'd
 *
 * 10/10/2000	Nicolas Pitre <[e-mail]>
 * 	- completely revamped method functions so they are aware and
 * 	  independent of the flash geometry (buswidth, interleave, etc.)
 * 	- scalability vs code size is completely set at compile-time
 * 	  (see include/linux/mtd/cfi.h for selection)
 *	- optimized write buffer method
 * 06/21/2002	Joern Engel <[e-mail]> and others
 *	- modified Intel Command Set 0x0001 to support ST Advanced Architecture
 *	  (command set 0x0020)
 *	- added a writev function
 * 07/13/2005	Joern Engel <[e-mail]>
 * 	- Plugged memory leak in cfi_staa_writev().
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <asm/io.h>
#include <asm/byteorder.h>

#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/mtd/map.h>
#include <linux/mtd/cfi.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/compatmac.h>


static int cfi_staa_read(struct mtd_info *, loff_t, size_t, size_t *, u_char *);
static int cfi_staa_write_buffers(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
static int cfi_staa_writev(struct mtd_info *mtd, const struct kvec *vecs,
		unsigned long count, loff_t to, size_t *retlen);
static int cfi_staa_erase_varsize(struct mtd_info *, struct erase_info *);
static void cfi_staa_sync (struct mtd_info *);
static int cfi_staa_lock(struct mtd_info *mtd, loff_t ofs, size_t len);
static int cfi_staa_unlock(struct mtd_info *mtd, loff_t ofs, size_t len);
static int cfi_staa_suspend (struct mtd_info *);
static void cfi_staa_resume (struct mtd_info *);

static void cfi_staa_destroy(struct mtd_info *);

struct mtd_info *cfi_cmdset_0020(struct map_info *, int);

static struct mtd_info *cfi_staa_setup (struct map_info *);

static struct mtd_chip_driver cfi_staa_chipdrv = {
	.probe		= NULL, /* Not usable directly */
	.destroy	= cfi_staa_destroy,
	.name		= "cfi_cmdset_0020",
	.module		= THIS_MODULE
};

/* #define DEBUG_LOCK_BITS */
//#define DEBUG_CFI_FEATURES

#ifdef DEBUG_CFI_FEATURES
static void cfi_tell_features(struct cfi_pri_intelext *extp)
{
        int i;
        printk("  Feature/Command Support: %4.4X\n", extp->FeatureSupport);
	printk("     - Chip Erase:         %s\n", extp->FeatureSupport&1?"supported":"unsupported");
	printk("     - Suspend Erase:      %s\n", extp->FeatureSupport&2?"supported":"unsupported");
	printk("     - Suspend Program:    %s\n", extp->FeatureSupport&4?"supported":"unsupported");
	printk("     - Legacy Lock/Unlock: %s\n", extp->FeatureSupport&8?"supported":"unsupported");
	printk("     - Queued Erase:       %s\n", extp->FeatureSupport&16?"supported":"unsupported");
	printk("     - Instant block lock: %s\n", extp->FeatureSupport&32?"supported":"unsupported");
	printk("     - Protection Bits:    %s\n", extp->FeatureSupport&64?"supported":"unsupported");
	printk("     - Page-mode read:     %s\n", extp->FeatureSupport&128?"supported":"unsupported");
	printk("     - Synchronous read:   %s\n", extp->FeatureSupport&256?"supported":"unsupported");
	for (i=9; i<32; i++) {
		if (extp->FeatureSupport & (1<<i))
			printk("     - Unknown Bit %X:      supported\n", i);
	}

	printk("  Supported functions after Suspend: %2.2X\n", extp->SuspendCmdSupport);
	printk("     - Program after Erase Suspend: %s\n", extp->SuspendCmdSupport&1?"supported":"unsupported");
	for (i=1; i<8; i++) {
		if (extp->SuspendCmdSupport & (1<<i))
			printk("     - Unknown Bit %X:               supported\n", i);
	}

	printk("  Block Status Register Mask: %4.4X\n", extp->BlkStatusRegMask);
	printk("     - Lock Bit Active:      %s\n", extp->BlkStatusRegMask&1?"yes":"no");
	printk("     - Valid Bit Active:     %s\n", extp->BlkStatusRegMask&2?"yes":"no");
	for (i=2; i<16; i++) {
		if (extp->BlkStatusRegMask & (1<<i))
			printk("     - Unknown Bit %X Active: yes\n",i);
	}

	printk("  Vcc Logic Supply Optimum Program/Erase Voltage: %d.%d V\n",
	       extp->VccOptimal >> 8, extp->VccOptimal & 0xf);
	if (extp->VppOptimal)
		printk("  Vpp Programming Supply Optimum Program/Erase Voltage: %d.%d V\n",
		       extp->VppOptimal >> 8, extp->VppOptimal & 0xf);
}
#endif

/* This routine is made available to other mtd code via
 * inter_module_register.  It must only be accessed through
 * inter_module_get which will bump the use count of this module.  The
 * addresses passed back in cfi are valid as long as the use count of
 * this module is non-zero, i.e. between inter_module_get and
 * inter_module_put.  Keith Owens <[e-mail]> 29 Oct 2000.
 */
struct mtd_info *cfi_cmdset_0020(struct map_info *map, int primary)
{
	struct cfi_private *cfi = map->fldrv_priv;
	int i;

	if (cfi->cfi_mode) {
		/*
		 * It's a real CFI chip, not one for which the probe
		 * routine faked a CFI structure. So we read the feature
		 * table from it.
		 */
		__u16 adr = primary?cfi->cfiq->P_ADR:cfi->cfiq->A_ADR;
		struct cfi_pri_intelext *extp;

		extp = (struct cfi_pri_intelext*)cfi_read_pri(map, adr, sizeof(*extp), "ST Microelectronics");
		if (!extp)
			return NULL;

		if (extp->MajorVersion != '1' ||
		    (extp->MinorVersion < '0' || extp->MinorVersion > '3')) {
			printk(KERN_ERR "  Unknown ST Microelectronics"
			       " Extended Query version %c.%c.\n",
			       extp->MajorVersion, extp->MinorVersion);
			kfree(extp);
			return NULL;
		}

		/* Do some byteswapping if necessary */
		extp->FeatureSupport = cfi32_to_cpu(extp->FeatureSupport);
		extp->BlkStatusRegMask = cfi32_to_cpu(extp->BlkStatusRegMask);

#ifdef DEBUG_CFI_FEATURES
		/* Tell the user about it in lots of lovely detail */
		cfi_tell_features(extp);
#endif

		/* Install our own private info structure */
		cfi->cmdset_priv = extp;
	}

	for (i=0; i< cfi->numchips; i++) {
		cfi->chips[i].word_write_time = 128;
		cfi->chips[i].buffer_write_time = 128;
		cfi->chips[i].erase_time = 1024;
		cfi->chips[i].ref_point_counter = 0;
		init_waitqueue_head(&(cfi->chips[i].wq));
	}

	return cfi_staa_setup(map);
}
EXPORT_SYMBOL_GPL(cfi_cmdset_0020);

static struct mtd_info *cfi_staa_setup(struct map_info *map)
{
	struct cfi_private *cfi = map->fldrv_priv;
	struct mtd_info *mtd;
	unsigned long offset = 0;
	int i,j;
	unsigned long devsize = (1<<cfi->cfiq->DevSize) * cfi->interleave;

	mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
	//printk(KERN_DEBUG "number of CFI chips: %d\n", cfi->numchips);

	if (!mtd) {
		printk(KERN_ERR "Failed to allocate memory for MTD device\n");
		kfree(cfi->cmdset_priv);
		return NULL;
	}

	mtd->priv = map;
	mtd->type = MTD_NORFLASH;
	mtd->size = devsize * cfi->numchips;

	mtd->numeraseregions = cfi->cfiq->NumEraseRegions * cfi->numchips;
	mtd->eraseregions = kmalloc(sizeof(struct mtd_erase_region_info)
			* mtd->numeraseregions, GFP_KERNEL);
	if (!mtd->eraseregions) {
		printk(KERN_ERR "Failed to allocate memory for MTD erase region info\n");
		kfree(cfi->cmdset_priv);
		kfree(mtd);
		return NULL;
	}

	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
		unsigned long ernum, ersize;
		ersize = ((cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff) * cfi->interleave;
		ernum = (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1;

		if (mtd->erasesize < ersize) {
			mtd->erasesize = ersize;
		}
		for (j=0; j<cfi->numchips; j++) {
			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].offset = (j*devsize)+offset;
			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].erasesize = ersize;
			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].numblocks = ernum;
		}
		offset += (ersize * ernum);
		}

		if (offset != devsize) {
			/* Argh */
			printk(KERN_WARNING "Sum of regions (%lx) != total size of set of interleaved chips (%lx)\n", offset, devsize);
			kfree(mtd->eraseregions);
			kfree(cfi->cmdset_priv);
			kfree(mtd);
			return NULL;
		}

		for (i=0; i<mtd->numeraseregions;i++){
			printk(KERN_DEBUG "%d: offset=0x%x,size=0x%x,blocks=%d\n",
			       i,mtd->eraseregions[i].offset,
			       mtd->eraseregions[i].erasesize,
			       mtd->eraseregions[i].numblocks);
		}

	/* Also select the correct geometry setup too */
	mtd->erase = cfi_staa_erase_varsize;
	mtd->read = cfi_staa_read;
        mtd->write = cfi_staa_write_buffers;
	mtd->writev = cfi_staa_writev;
	mtd->sync = cfi_staa_sync;
	mtd->lock = cfi_staa_lock;
	mtd->unlock = cfi_staa_unlock;
	mtd->suspend = cfi_staa_suspend;
	mtd->resume = cfi_staa_resume;
	mtd->flags = MTD_CAP_NORFLASH & ~MTD_BIT_WRITEABLE;
	mtd->writesize = 8; /* FIXME: Should be 0 for STMicro flashes w/out ECC */
	map->fldrv = &cfi_staa_chipdrv;
	__module_get(THIS_MODULE);
	mtd->name = map->name;
	return mtd;
}


static inline int do_read_onechip(struct map_info *map, struct flchip *chip, loff_t adr, size_t len, u_char *buf)
{
	map_word status, status_OK;
	unsigned long timeo;
	DECLARE_WAITQUEUE(wait, current);
	int suspended = 0;
	unsigned long cmd_addr;
	struct cfi_private *cfi = map->fldrv_priv;

	adr += chip->start;

	/* Ensure cmd read/writes are aligned. */
	cmd_addr = adr & ~(map_bankwidth(map)-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.
	 * If it's in FL_ERASING state, suspend it and make it talk now.
	 */
	switch (chip->state) {
	case FL_ERASING:
		if (!(((struct cfi_pri_intelext *)cfi->cmdset_priv)->FeatureSupport & 2))
			goto sleep; /* We don't support erase suspend */

		map_write (map, CMD(0xb0), cmd_addr);
		/* If the flash has finished erasing, then 'erase suspend'
		 * appears to make some (28F320) flash devices switch to
		 * 'read' mode.  Make sure that we switch to 'read status'
		 * mode so we get the right data. --rmk
		 */
		map_write(map, CMD(0x70), cmd_addr);
		chip->oldstate = FL_ERASING;
		chip->state = FL_ERASE_SUSPENDING;
		//		printk("Erase suspending at 0x%lx\n", cmd_addr);
		for (;;) {
			status = map_read(map, cmd_addr);
			if (map_word_andequal(map, status, status_OK, status_OK))
				break;

			if (time_after(jiffies, timeo)) {
				/* Urgh */
				map_write(map, CMD(0xd0), cmd_addr);
				/* make sure we're in 'read status' mode */
				map_write(map, CMD(0x70), cmd_addr);
				chip->state = FL_ERASING;
				spin_unlock_bh(chip->mutex);
				printk(KERN_ERR "Chip not ready after erase "
				       "suspended: status = 0x%lx\n", status.x[0]);
				return -EIO;
			}

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

		suspended = 1;
		map_write(map, CMD(0xff), cmd_addr);
		chip->state = FL_READY;
		break;

#if 0
	case FL_WRITING:
		/* Not quite yet */
#endif

	case FL_READY:
		break;

	case FL_CFI_QUERY:
	case FL_JEDEC_QUERY:
		map_write(map, CMD(0x70), cmd_addr);
		chip->state = FL_STATUS;

	case FL_STATUS:
		status = map_read(map, cmd_addr);
		if (map_word_andequal(map, status, status_OK, status_OK)) {
			map_write(map, CMD(0xff), cmd_addr);
			chip->state = FL_READY;
			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. WSM status = %lx\n", status.x[0]);
			return -EIO;
		}

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

	default:
	sleep:
		/* 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;
	}

	map_copy_from(map, buf, adr, len);

	if (suspended) {
		chip->state = chip->oldstate;
		/* What if one interleaved chip has finished and the
		   other hasn't? The old code would leave the finished
		   one in READY mode. That's bad, and caused -EROFS
		   errors to be returned from do_erase_oneblock because
		   that's the only bit it checked for at the time.
		   As the state machine appears to explicitly allow
		   sending the 0x70 (Read Status) command to an erasing
		   chip and expecting it to be ignored, that's what we
		   do. */
		map_write(map, CMD(0xd0), cmd_addr);
		map_write(map, CMD(0x70), cmd_addr);
	}

	wake_up(&chip->wq);
	spin_unlock_bh(chip->mutex);
	return 0;
}

static int cfi_staa_read (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;
	unsigned long ofs;
	int chipnum;
	int ret = 0;

	/* ofs: offset within the first chip that the first read should start */
	chipnum = (from >> cfi->chipshift);
	ofs = from - (chipnum <<  cfi->chipshift);

	*retlen = 0;

	while (len) {
		unsigned long thislen;

		if (chipnum >= cfi->numchips)
			break;

		if ((len + ofs -1) >> cfi->chipshift)
			thislen = (1<<cfi->chipshift) - ofs;
		else
			thislen = len;

		ret = do_read_onechip(map, &cfi->chips[chipnum], ofs, thislen, buf);
		if (ret)
			break;

		*retlen += thislen;
		len -= thislen;
		buf += thislen;

		ofs = 0;
		chipnum++;
	}
	return ret;
}

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;
	map_word status, status_OK;
	unsigned long cmd_adr, timeo;
	DECLARE_WAITQUEUE(wait, current);
	int wbufsize, z;

        /* M58LW064A requires bus alignment for buffer wriets -- saw */
        if (adr & (map_bankwidth(map)-1))
            return -EINVAL;

        wbufsize = cfi_interleave(cfi) << 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:

#ifdef DEBUG_CFI_FEATURES
       printk("%s: chip->state[%d]\n", __func__, chip->state);
#endif
	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:
		map_write(map, CMD(0x70), cmd_adr);
                chip->state = FL_STATUS;
#ifdef DEBUG_CFI_FEATURES
	printk("%s: 1 status[%x]\n", __func__, map_read(map, cmd_adr));
#endif

	case FL_STATUS:
		status = map_read(map, cmd_adr);
		if (map_word_andequal(map, status, status_OK, status_OK))
			break;
		/* Urgh. Chip not yet ready to talk to us. */
		if (time_after(jiffies, timeo)) {