[MTD] NAND cleanup nand_scan
Linux-MTD Mailing List
linux-mtd at lists.infradead.org
Tue May 23 06:59:04 EDT 2006
Commit: 7aa65bfd6793a56cc3bbce8436abbfea3a7bdd1f
Parent: 58dd8f2bfdcad1b219a4a92a2aadd8ea8c819f79
Author: Thomas Gleixner <tglx at cruncher.tec.linutronix.de>
AuthorDate: Tue May 23 11:54:38 2006 +0200
Commit: Thomas Gleixner <tglx at cruncher.tec.linutronix.de>
CommitDate: Tue May 23 11:54:38 2006 +0200
[MTD] NAND cleanup nand_scan
Seperate functionality out of nand_scan so the code is more
readable. No functional change. First step of simplifying
the nand driver.
Signed-off-by: Thomas Gleixner <tglx at linutronix.de>
drivers/mtd/nand/nand_base.c | 407 ++++++++++++++++++++++++------------------
1 files changed, 233 insertions(+), 174 deletions(-)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index afa77d1..37db98a 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -76,6 +76,7 @@
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/errno.h>
+#include <linux/err.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/types.h>
@@ -2333,42 +2334,50 @@ static void nand_free_kmem(struct nand_c
kfree(this->controller);
}
-/* module_text_address() isn't exported, and it's mostly a pointless
- test if this is a module _anyway_ -- they'd have to try _really_ hard
- to call us from in-kernel code if the core NAND support is modular. */
-#ifdef MODULE
-#define caller_is_module() (1)
-#else
-#define caller_is_module() module_text_address((unsigned long)__builtin_return_address(0))
-#endif
-
-/**
- * nand_scan - [NAND Interface] Scan for the NAND device
- * @mtd: MTD device structure
- * @maxchips: Number of chips to scan for
- *
- * This fills out all the uninitialized function pointers
- * with the defaults.
- * The flash ID is read and the mtd/chip structures are
- * filled with the appropriate values. Buffers are allocated if
- * they are not provided by the board driver
- * The mtd->owner field must be set to the module of the caller
- *
+/*
+ * Allocate buffers and data structures
*/
-int nand_scan(struct mtd_info *mtd, int maxchips)
+static int nand_allocate_kmem(struct mtd_info *mtd, struct nand_chip *this)
{
- int i, nand_maf_id, nand_dev_id, busw, maf_id;
- struct nand_chip *this = mtd->priv;
+ size_t len;
- /* Many callers got this wrong, so check for it for a while... */
- if (!mtd->owner && caller_is_module()) {
- printk(KERN_CRIT "nand_scan() called with NULL mtd->owner!\n");
- BUG();
+ if (!this->oob_buf) {
+ len = mtd->oobsize <<
+ (this->phys_erase_shift - this->page_shift);
+ this->oob_buf = kmalloc(len, GFP_KERNEL);
+ if (!this->oob_buf)
+ goto outerr;
+ this->options |= NAND_OOBBUF_ALLOC;
}
- /* Get buswidth to select the correct functions */
- busw = this->options & NAND_BUSWIDTH_16;
+ if (!this->data_buf) {
+ len = mtd->oobblock + mtd->oobsize;
+ this->data_buf = kmalloc(len, GFP_KERNEL);
+ if (!this->data_buf)
+ goto outerr;
+ this->options |= NAND_DATABUF_ALLOC;
+ }
+ if (!this->controller) {
+ this->controller = kzalloc(sizeof(struct nand_hw_control),
+ GFP_KERNEL);
+ if (!this->controller)
+ goto outerr;
+ this->options |= NAND_CONTROLLER_ALLOC;
+ }
+ return 0;
+
+ outerr:
+ printk(KERN_ERR "nand_scan(): Cannot allocate buffers\n");
+ nand_free_kmem(this);
+ return -ENOMEM;
+}
+
+/*
+ * Set default functions
+ */
+static void nand_set_defaults(struct nand_chip *this, int busw)
+{
/* check for proper chip_delay setup, set 20us if not */
if (!this->chip_delay)
this->chip_delay = 20;
@@ -2403,6 +2412,17 @@ int nand_scan(struct mtd_info *mtd, int
this->verify_buf = busw ? nand_verify_buf16 : nand_verify_buf;
if (!this->scan_bbt)
this->scan_bbt = nand_default_bbt;
+}
+
+/*
+ * Get the flash and manufacturer id and lookup if the typ is supported
+ */
+static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
+ struct nand_chip *this,
+ int busw, int *maf_id)
+{
+ struct nand_flash_dev *type = NULL;
+ int i, dev_id, maf_idx;
/* Select the device */
this->select_chip(mtd, 0);
@@ -2411,158 +2431,194 @@ int nand_scan(struct mtd_info *mtd, int
this->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
/* Read manufacturer and device IDs */
- nand_maf_id = this->read_byte(mtd);
- nand_dev_id = this->read_byte(mtd);
+ *maf_id = this->read_byte(mtd);
+ dev_id = this->read_byte(mtd);
- /* Print and store flash device information */
+ /* Lookup the flash id */
for (i = 0; nand_flash_ids[i].name != NULL; i++) {
+ if (dev_id == nand_flash_ids[i].id) {
+ type = &nand_flash_ids[i];
+ break;
+ }
+ }
- if (nand_dev_id != nand_flash_ids[i].id)
- continue;
-
- if (!mtd->name)
- mtd->name = nand_flash_ids[i].name;
- this->chipsize = nand_flash_ids[i].chipsize << 20;
-
- /* New devices have all the information in additional id bytes */
- if (!nand_flash_ids[i].pagesize) {
- int extid;
- /* The 3rd id byte contains non relevant data ATM */
- extid = this->read_byte(mtd);
- /* The 4th id byte is the important one */
- extid = this->read_byte(mtd);
- /* Calc pagesize */
- mtd->oobblock = 1024 << (extid & 0x3);
- extid >>= 2;
- /* Calc oobsize */
- mtd->oobsize = (8 << (extid & 0x01)) * (mtd->oobblock >> 9);
- extid >>= 2;
- /* Calc blocksize. Blocksize is multiples of 64KiB */
- mtd->erasesize = (64 * 1024) << (extid & 0x03);
- extid >>= 2;
- /* Get buswidth information */
- busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
+ if (!type)
+ return ERR_PTR(-ENODEV);
+
+ this->chipsize = nand_flash_ids[i].chipsize << 20;
+
+ /* Newer devices have all the information in additional id bytes */
+ if (!nand_flash_ids[i].pagesize) {
+ int extid;
+ /* The 3rd id byte contains non relevant data ATM */
+ extid = this->read_byte(mtd);
+ /* The 4th id byte is the important one */
+ extid = this->read_byte(mtd);
+ /* Calc pagesize */
+ mtd->oobblock = 1024 << (extid & 0x3);
+ extid >>= 2;
+ /* Calc oobsize */
+ mtd->oobsize = (8 << (extid & 0x01)) * (mtd->oobblock >> 9);
+ extid >>= 2;
+ /* Calc blocksize. Blocksize is multiples of 64KiB */
+ mtd->erasesize = (64 * 1024) << (extid & 0x03);
+ extid >>= 2;
+ /* Get buswidth information */
+ busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
- } else {
- /* Old devices have this data hardcoded in the
- * device id table */
- mtd->erasesize = nand_flash_ids[i].erasesize;
- mtd->oobblock = nand_flash_ids[i].pagesize;
- mtd->oobsize = mtd->oobblock / 32;
- busw = nand_flash_ids[i].options & NAND_BUSWIDTH_16;
- }
+ } else {
+ /*
+ * Old devices have this data hardcoded in the device id table
+ */
+ mtd->erasesize = nand_flash_ids[i].erasesize;
+ mtd->oobblock = nand_flash_ids[i].pagesize;
+ mtd->oobsize = mtd->oobblock / 32;
+ busw = nand_flash_ids[i].options & NAND_BUSWIDTH_16;
+ }
- /* Try to identify manufacturer */
- for (maf_id = 0; nand_manuf_ids[maf_id].id != 0x0; maf_id++) {
- if (nand_manuf_ids[maf_id].id == nand_maf_id)
- break;
- }
+ /* Try to identify manufacturer */
+ for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_id++) {
+ if (nand_manuf_ids[maf_idx].id == *maf_id)
+ break;
+ }
- /* Check, if buswidth is correct. Hardware drivers should set
- * this correct ! */
- if (busw != (this->options & NAND_BUSWIDTH_16)) {
- printk(KERN_INFO "NAND device: Manufacturer ID:"
- " 0x%02x, Chip ID: 0x%02x (%s %s)\n", nand_maf_id, nand_dev_id,
- nand_manuf_ids[maf_id].name, mtd->name);
- printk(KERN_WARNING
- "NAND bus width %d instead %d bit\n",
- (this->options & NAND_BUSWIDTH_16) ? 16 : 8, busw ? 16 : 8);
- this->select_chip(mtd, -1);
- return 1;
- }
+ /*
+ * Check, if buswidth is correct. Hardware drivers should set
+ * this correct !
+ */
+ if (busw != (this->options & NAND_BUSWIDTH_16)) {
+ printk(KERN_INFO "NAND device: Manufacturer ID:"
+ " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id,
+ dev_id, nand_manuf_ids[maf_idx].name, mtd->name);
+ printk(KERN_WARNING "NAND bus width %d instead %d bit\n",
+ (this->options & NAND_BUSWIDTH_16) ? 16 : 8,
+ busw ? 16 : 8);
+ return ERR_PTR(-EINVAL);
+ }
- /* Calculate the address shift from the page size */
- this->page_shift = ffs(mtd->oobblock) - 1;
- this->bbt_erase_shift = this->phys_erase_shift = ffs(mtd->erasesize) - 1;
- this->chip_shift = ffs(this->chipsize) - 1;
-
- /* Set the bad block position */
- this->badblockpos = mtd->oobblock > 512 ? NAND_LARGE_BADBLOCK_POS : NAND_SMALL_BADBLOCK_POS;
-
- /* Get chip options, preserve non chip based options */
- this->options &= ~NAND_CHIPOPTIONS_MSK;
- this->options |= nand_flash_ids[i].options & NAND_CHIPOPTIONS_MSK;
- /* Set this as a default. Board drivers can override it, if necessary */
- this->options |= NAND_NO_AUTOINCR;
- /* Check if this is a not a samsung device. Do not clear the options
- * for chips which are not having an extended id.
- */
- if (nand_maf_id != NAND_MFR_SAMSUNG && !nand_flash_ids[i].pagesize)
- this->options &= ~NAND_SAMSUNG_LP_OPTIONS;
+ /* Calculate the address shift from the page size */
+ this->page_shift = ffs(mtd->oobblock) - 1;
+ /* Convert chipsize to number of pages per chip -1. */
+ this->pagemask = (this->chipsize >> this->page_shift) - 1;
- /* Check for AND chips with 4 page planes */
- if (this->options & NAND_4PAGE_ARRAY)
- this->erase_cmd = multi_erase_cmd;
- else
- this->erase_cmd = single_erase_cmd;
+ this->bbt_erase_shift = this->phys_erase_shift =
+ ffs(mtd->erasesize) - 1;
+ this->chip_shift = ffs(this->chipsize) - 1;
- /* Do not replace user supplied command function ! */
- if (mtd->oobblock > 512 && this->cmdfunc == nand_command)
- this->cmdfunc = nand_command_lp;
+ /* Set the bad block position */
+ this->badblockpos = mtd->oobblock > 512 ?
+ NAND_LARGE_BADBLOCK_POS : NAND_SMALL_BADBLOCK_POS;
- printk(KERN_INFO "NAND device: Manufacturer ID:"
- " 0x%02x, Chip ID: 0x%02x (%s %s)\n", nand_maf_id, nand_dev_id,
- nand_manuf_ids[maf_id].name, nand_flash_ids[i].name);
- break;
+ /* Get chip options, preserve non chip based options */
+ this->options &= ~NAND_CHIPOPTIONS_MSK;
+ this->options |= nand_flash_ids[i].options & NAND_CHIPOPTIONS_MSK;
+
+ /*
+ * Set this as a default. Board drivers can override it, if necessary
+ */
+ this->options |= NAND_NO_AUTOINCR;
+
+ /* Check if this is a not a samsung device. Do not clear the
+ * options for chips which are not having an extended id.
+ */
+ if (*maf_id != NAND_MFR_SAMSUNG && !nand_flash_ids[i].pagesize)
+ this->options &= ~NAND_SAMSUNG_LP_OPTIONS;
+
+ /* Check for AND chips with 4 page planes */
+ if (this->options & NAND_4PAGE_ARRAY)
+ this->erase_cmd = multi_erase_cmd;
+ else
+ this->erase_cmd = single_erase_cmd;
+
+ /* Do not replace user supplied command function ! */
+ if (mtd->oobblock > 512 && this->cmdfunc == nand_command)
+ this->cmdfunc = nand_command_lp;
+
+ printk(KERN_INFO "NAND device: Manufacturer ID:"
+ " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id, dev_id,
+ nand_manuf_ids[maf_idx].name, type->name);
+
+ return type;
+}
+
+/* module_text_address() isn't exported, and it's mostly a pointless
+ test if this is a module _anyway_ -- they'd have to try _really_ hard
+ to call us from in-kernel code if the core NAND support is modular. */
+#ifdef MODULE
+#define caller_is_module() (1)
+#else
+#define caller_is_module() \
+ module_text_address((unsigned long)__builtin_return_address(0))
+#endif
+
+/**
+ * nand_scan - [NAND Interface] Scan for the NAND device
+ * @mtd: MTD device structure
+ * @maxchips: Number of chips to scan for
+ *
+ * This fills out all the uninitialized function pointers
+ * with the defaults.
+ * The flash ID is read and the mtd/chip structures are
+ * filled with the appropriate values. Buffers are allocated if
+ * they are not provided by the board driver
+ * The mtd->owner field must be set to the module of the caller
+ *
+ */
+int nand_scan(struct mtd_info *mtd, int maxchips)
+{
+ int i, busw, nand_maf_id;
+ struct nand_chip *this = mtd->priv;
+ struct nand_flash_dev *type;
+
+ /* Many callers got this wrong, so check for it for a while... */
+ if (!mtd->owner && caller_is_module()) {
+ printk(KERN_CRIT "nand_scan() called with NULL mtd->owner!\n");
+ BUG();
}
- if (!nand_flash_ids[i].name) {
+ /* Get buswidth to select the correct functions */
+ busw = this->options & NAND_BUSWIDTH_16;
+ /* Set the default functions */
+ nand_set_defaults(this, busw);
+
+ /* Read the flash type */
+ type = nand_get_flash_type(mtd, this, busw, &nand_maf_id);
+
+ if (IS_ERR(type)) {
printk(KERN_WARNING "No NAND device found!!!\n");
this->select_chip(mtd, -1);
- return 1;
+ return PTR_ERR(type);
}
+ /* Check for a chip array */
for (i = 1; i < maxchips; i++) {
this->select_chip(mtd, i);
-
/* Send the command for reading device ID */
this->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
-
/* Read manufacturer and device IDs */
if (nand_maf_id != this->read_byte(mtd) ||
- nand_dev_id != this->read_byte(mtd))
+ type->id != this->read_byte(mtd))
break;
}
if (i > 1)
printk(KERN_INFO "%d NAND chips detected\n", i);
- /* Allocate buffers, if necessary */
- if (!this->oob_buf) {
- size_t len;
- len = mtd->oobsize << (this->phys_erase_shift - this->page_shift);
- this->oob_buf = kmalloc(len, GFP_KERNEL);
- if (!this->oob_buf) {
- printk(KERN_ERR "nand_scan(): Cannot allocate oob_buf\n");
- return -ENOMEM;
- }
- this->options |= NAND_OOBBUF_ALLOC;
- }
-
- if (!this->data_buf) {
- size_t len;
- len = mtd->oobblock + mtd->oobsize;
- this->data_buf = kmalloc(len, GFP_KERNEL);
- if (!this->data_buf) {
- printk(KERN_ERR "nand_scan(): Cannot allocate data_buf\n");
- nand_free_kmem(this);
- return -ENOMEM;
- }
- this->options |= NAND_DATABUF_ALLOC;
- }
-
/* Store the number of chips and calc total size for mtd */
this->numchips = i;
mtd->size = i * this->chipsize;
- /* Convert chipsize to number of pages per chip -1. */
- this->pagemask = (this->chipsize >> this->page_shift) - 1;
+
+ /* Allocate buffers and data structures */
+ if (nand_allocate_kmem(mtd, this))
+ return -ENOMEM;
+
/* Preset the internal oob buffer */
- memset(this->oob_buf, 0xff, mtd->oobsize << (this->phys_erase_shift - this->page_shift));
+ memset(this->oob_buf, 0xff,
+ mtd->oobsize << (this->phys_erase_shift - this->page_shift));
- /* If no default placement scheme is given, select an
- * appropriate one */
+ /*
+ * If no default placement scheme is given, select an appropriate one
+ */
if (!this->autooob) {
- /* Select the appropriate default oob placement scheme for
- * placement agnostic filesystems */
switch (mtd->oobsize) {
case 8:
this->autooob = &nand_oob_8;
@@ -2574,29 +2630,32 @@ int nand_scan(struct mtd_info *mtd, int
this->autooob = &nand_oob_64;
break;
default:
- printk(KERN_WARNING "No oob scheme defined for oobsize %d\n", mtd->oobsize);
+ printk(KERN_WARNING "No oob scheme defined for "
+ "oobsize %d\n", mtd->oobsize);
BUG();
}
}
- /* The number of bytes available for the filesystem to place fs dependend
- * oob data */
+ /*
+ * The number of bytes available for the filesystem to place fs
+ * dependend oob data
+ */
mtd->oobavail = 0;
for (i = 0; this->autooob->oobfree[i][1]; i++)
mtd->oobavail += this->autooob->oobfree[i][1];
/*
- * check ECC mode, default to software
- * if 3byte/512byte hardware ECC is selected and we have 256 byte pagesize
- * fallback to software ECC
+ * check ECC mode, default to software if 3byte/512byte hardware ECC is
+ * selected and we have 256 byte pagesize fallback to software ECC
*/
- this->eccsize = 256; /* set default eccsize */
+ this->eccsize = 256;
this->eccbytes = 3;
switch (this->eccmode) {
case NAND_ECC_HW12_2048:
if (mtd->oobblock < 2048) {
- printk(KERN_WARNING "2048 byte HW ECC not possible on %d byte page size, fallback to SW ECC\n",
+ printk(KERN_WARNING "2048 byte HW ECC not possible on "
+ "%d byte page size, fallback to SW ECC\n",
mtd->oobblock);
this->eccmode = NAND_ECC_SOFT;
this->calculate_ecc = nand_calculate_ecc;
@@ -2609,7 +2668,8 @@ int nand_scan(struct mtd_info *mtd, int
case NAND_ECC_HW6_512:
case NAND_ECC_HW8_512:
if (mtd->oobblock == 256) {
- printk(KERN_WARNING "512 byte HW ECC not possible on 256 Byte pagesize, fallback to SW ECC \n");
+ printk(KERN_WARNING "512 byte HW ECC not possible on "
+ "256 Byte pagesize, fallback to SW ECC \n");
this->eccmode = NAND_ECC_SOFT;
this->calculate_ecc = nand_calculate_ecc;
this->correct_data = nand_correct_data;
@@ -2621,7 +2681,8 @@ int nand_scan(struct mtd_info *mtd, int
break;
case NAND_ECC_NONE:
- printk(KERN_WARNING "NAND_ECC_NONE selected by board driver. This is not recommended !!\n");
+ printk(KERN_WARNING "NAND_ECC_NONE selected by board driver. "
+ "This is not recommended !!\n");
this->eccmode = NAND_ECC_NONE;
break;
@@ -2631,12 +2692,14 @@ int nand_scan(struct mtd_info *mtd, int
break;
default:
- printk(KERN_WARNING "Invalid NAND_ECC_MODE %d\n", this->eccmode);
+ printk(KERN_WARNING "Invalid NAND_ECC_MODE %d\n",
+ this->eccmode);
BUG();
}
- /* Check hardware ecc function availability and adjust number of ecc bytes per
- * calculation step
+ /*
+ * Check hardware ecc function availability and adjust number of ecc
+ * bytes per calculation step
*/
switch (this->eccmode) {
case NAND_ECC_HW12_2048:
@@ -2647,15 +2710,20 @@ int nand_scan(struct mtd_info *mtd, int
this->eccbytes += 3;
case NAND_ECC_HW3_512:
case NAND_ECC_HW3_256:
- if (this->calculate_ecc && this->correct_data && this->enable_hwecc)
+ if (this->calculate_ecc && this->correct_data &&
+ this->enable_hwecc)
break;
- printk(KERN_WARNING "No ECC functions supplied, Hardware ECC not possible\n");
+ printk(KERN_WARNING "No ECC functions supplied, "
+ "Hardware ECC not possible\n");
BUG();
}
mtd->eccsize = this->eccsize;
- /* Set the number of read / write steps for one page to ensure ECC generation */
+ /*
+ * Set the number of read / write steps for one page depending on ECC
+ * mode
+ */
switch (this->eccmode) {
case NAND_ECC_HW12_2048:
this->eccsteps = mtd->oobblock / 2048;
@@ -2677,15 +2745,6 @@ int nand_scan(struct mtd_info *mtd, int
/* Initialize state, waitqueue and spinlock */
this->state = FL_READY;
- if (!this->controller) {
- this->controller = kzalloc(sizeof(struct nand_hw_control),
- GFP_KERNEL);
- if (!this->controller) {
- nand_free_kmem(this);
- return -ENOMEM;
- }
- this->options |= NAND_CONTROLLER_ALLOC;
- }
init_waitqueue_head(&this->controller->wq);
spin_lock_init(&this->controller->lock);
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