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Commit 7aa65bfd authored by Thomas Gleixner's avatar Thomas Gleixner
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[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: default avatarThomas Gleixner <tglx@linutronix.de>
parent 58dd8f2b
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Showing with 233 additions and 174 deletions
drivers/mtd/nand/nand_base.c
View file @ 7aa65bfd
......@@ -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_chip *this)
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 maxchips)
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);
......@@ -2411,20 +2431,23 @@ int nand_scan(struct mtd_info *mtd, int maxchips)
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 (!type)
return ERR_PTR(-ENODEV);
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 */
/* 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 */
......@@ -2444,8 +2467,9 @@ int nand_scan(struct mtd_info *mtd, int maxchips)
busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
} else {
/* Old devices have this data hardcoded in the
* device id table */
/*
* 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;
......@@ -2453,41 +2477,51 @@ int nand_scan(struct mtd_info *mtd, int maxchips)
}
/* 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)
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 ! */
/*
* 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;
" 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;
/* Convert chipsize to number of pages per chip -1. */
this->pagemask = (this->chipsize >> this->page_shift) - 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;
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 */
/*
* 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.
/* 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)
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 */
......@@ -2501,68 +2535,90 @@ int nand_scan(struct mtd_info *mtd, int maxchips)
this->cmdfunc = nand_command_lp;
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;
" 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 maxchips)
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 maxchips)
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 maxchips)
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 maxchips)
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 maxchips)
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 maxchips)
/* 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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