linux/drivers/mtd/tests/mtd_nandecctest.c
Akinobu Mita 7126bd8be4 mtd: add nand_ecc test module
This module tests NAND ECC functions.

The test is simple.

1. Create a 256 or 512 bytes block of data filled with random bytes (data)
2. Duplicate the data block and inject single bit error (error_data)
3. Try to correct error_data
4. Compare data and error_data

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Vimal Singh <vimalsingh@ti.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-11-30 09:41:49 +00:00

88 lines
1.8 KiB
C

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/string.h>
#include <linux/bitops.h>
#include <linux/jiffies.h>
#include <linux/mtd/nand_ecc.h>
#if defined(CONFIG_MTD_NAND) || defined(CONFIG_MTD_NAND_MODULE)
static void inject_single_bit_error(void *data, size_t size)
{
unsigned long offset = random32() % (size * BITS_PER_BYTE);
__change_bit(offset, data);
}
static unsigned char data[512];
static unsigned char error_data[512];
static int nand_ecc_test(const size_t size)
{
unsigned char code[3];
unsigned char error_code[3];
char testname[30];
BUG_ON(sizeof(data) < size);
sprintf(testname, "nand-ecc-%zu", size);
get_random_bytes(data, size);
memcpy(error_data, data, size);
inject_single_bit_error(error_data, size);
__nand_calculate_ecc(data, size, code);
__nand_calculate_ecc(error_data, size, error_code);
__nand_correct_data(error_data, code, error_code, size);
if (!memcmp(data, error_data, size)) {
printk(KERN_INFO "mtd_nandecctest: ok - %s\n", testname);
return 0;
}
printk(KERN_ERR "mtd_nandecctest: not ok - %s\n", testname);
printk(KERN_DEBUG "hexdump of data:\n");
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 16, 4,
data, size, false);
printk(KERN_DEBUG "hexdump of error data:\n");
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 16, 4,
error_data, size, false);
return -1;
}
#else
static int nand_ecc_test(const size_t size)
{
return 0;
}
#endif
static int __init ecc_test_init(void)
{
srandom32(jiffies);
nand_ecc_test(256);
nand_ecc_test(512);
return 0;
}
static void __exit ecc_test_exit(void)
{
}
module_init(ecc_test_init);
module_exit(ecc_test_exit);
MODULE_DESCRIPTION("NAND ECC function test module");
MODULE_AUTHOR("Akinobu Mita");
MODULE_LICENSE("GPL");