diff options
| -rw-r--r-- | Documentation/arm/Samsung-S3C24XX/NAND.txt | 30 | ||||
| -rw-r--r-- | Documentation/arm/Samsung-S3C24XX/Overview.txt | 2 | ||||
| -rw-r--r-- | drivers/mtd/nand/s3c2410.c | 38 |
3 files changed, 65 insertions, 5 deletions
diff --git a/Documentation/arm/Samsung-S3C24XX/NAND.txt b/Documentation/arm/Samsung-S3C24XX/NAND.txt new file mode 100644 index 00000000000..bc478a3409b --- /dev/null +++ b/Documentation/arm/Samsung-S3C24XX/NAND.txt @@ -0,0 +1,30 @@ + S3C24XX NAND Support + ==================== + +Introduction +------------ + +Small Page NAND +--------------- + +The driver uses a 512 byte (1 page) ECC code for this setup. The +ECC code is not directly compatible with the default kernel ECC +code, so the driver enforces its own OOB layout and ECC parameters + +Large Page NAND +--------------- + +The driver is capable of handling NAND flash with a 2KiB page +size, with support for hardware ECC generation and correction. + +Unlike the 512byte page mode, the driver generates ECC data for +each 256 byte block in an 2KiB page. This means that more than +one error in a page can be rectified. It also means that the +OOB layout remains the default kernel layout for these flashes. + + +Document Author +--------------- + +Ben Dooks, Copyright 2007 Simtec Electronics + diff --git a/Documentation/arm/Samsung-S3C24XX/Overview.txt b/Documentation/arm/Samsung-S3C24XX/Overview.txt index c31b76fa66c..d04e1e30c47 100644 --- a/Documentation/arm/Samsung-S3C24XX/Overview.txt +++ b/Documentation/arm/Samsung-S3C24XX/Overview.txt @@ -156,6 +156,8 @@ NAND controller. If there are any problems the latest linux-mtd code can be found from http://www.linux-mtd.infradead.org/ + For more information see Documentation/arm/Samsung-S3C24XX/NAND.txt + Serial ------ diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c index 8557c68dbb4..15397e0f396 100644 --- a/drivers/mtd/nand/s3c2410.c +++ b/drivers/mtd/nand/s3c2410.c @@ -472,7 +472,7 @@ static int s3c2440_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u ecc_code[1] = ecc >> 8; ecc_code[2] = ecc >> 16; - pr_debug("%s: returning ecc %06lx\n", __func__, ecc); + pr_debug("%s: returning ecc %06lx\n", __func__, ecc & 0xffffff); return 0; } @@ -643,9 +643,6 @@ static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info, chip->ecc.calculate = s3c2410_nand_calculate_ecc; chip->ecc.correct = s3c2410_nand_correct_data; chip->ecc.mode = NAND_ECC_HW; - chip->ecc.size = 512; - chip->ecc.bytes = 3; - chip->ecc.layout = &nand_hw_eccoob; switch (info->cpu_type) { case TYPE_S3C2410: @@ -669,6 +666,34 @@ static void s3c2410_nand_init_chip(struct s3c2410_nand_info *info, } } +/* s3c2410_nand_update_chip + * + * post-probe chip update, to change any items, such as the + * layout for large page nand + */ + +static void s3c2410_nand_update_chip(struct s3c2410_nand_info *info, + struct s3c2410_nand_mtd *nmtd) +{ + struct nand_chip *chip = &nmtd->chip; + + printk("%s: chip %p: %d\n", __func__, chip, chip->page_shift); + + if (hardware_ecc) { + /* change the behaviour depending on wether we are using + * the large or small page nand device */ + + if (chip->page_shift > 10) { + chip->ecc.size = 256; + chip->ecc.bytes = 3; + } else { + chip->ecc.size = 512; + chip->ecc.bytes = 3; + chip->ecc.layout = &nand_hw_eccoob; + } + } +} + /* s3c2410_nand_probe * * called by device layer when it finds a device matching @@ -775,9 +800,12 @@ static int s3c24xx_nand_probe(struct platform_device *pdev, s3c2410_nand_init_chip(info, nmtd, sets); - nmtd->scan_res = nand_scan(&nmtd->mtd, (sets) ? sets->nr_chips : 1); + nmtd->scan_res = nand_scan_ident(&nmtd->mtd, + (sets) ? sets->nr_chips : 1); if (nmtd->scan_res == 0) { + s3c2410_nand_update_chip(info, nmtd); + nand_scan_tail(&nmtd->mtd); s3c2410_nand_add_partition(info, nmtd, sets); } |