| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/list.h> |
| #include <linux/random.h> |
| #include <linux/string.h> |
| #include <linux/bitops.h> |
| #include <linux/slab.h> |
| #include <linux/mtd/nand_ecc.h> |
| |
| #if defined(CONFIG_MTD_NAND) || defined(CONFIG_MTD_NAND_MODULE) |
| |
| /* |
| * The reason for this __change_bit_le() instead of __change_bit() is to inject |
| * bit error properly within the region which is not a multiple of |
| * sizeof(unsigned long) on big-endian systems |
| */ |
| #ifdef __LITTLE_ENDIAN |
| #define __change_bit_le(nr, addr) __change_bit(nr, addr) |
| #elif defined(__BIG_ENDIAN) |
| #define __change_bit_le(nr, addr) \ |
| __change_bit((nr) ^ ((BITS_PER_LONG - 1) & ~0x7), addr) |
| #else |
| #error "Unknown byte order" |
| #endif |
| |
| static void inject_single_bit_error(void *data, size_t size) |
| { |
| unsigned int offset = random32() % (size * BITS_PER_BYTE); |
| |
| __change_bit_le(offset, data); |
| } |
| |
| static void dump_data_ecc(void *error_data, void *error_ecc, void *correct_data, |
| void *correct_ecc, const size_t size) |
| { |
| pr_info("hexdump of error data:\n"); |
| print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 4, |
| error_data, size, false); |
| print_hex_dump(KERN_INFO, "hexdump of error ecc: ", |
| DUMP_PREFIX_NONE, 16, 1, error_ecc, 3, false); |
| |
| pr_info("hexdump of correct data:\n"); |
| print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 4, |
| correct_data, size, false); |
| print_hex_dump(KERN_INFO, "hexdump of correct ecc: ", |
| DUMP_PREFIX_NONE, 16, 1, correct_ecc, 3, false); |
| } |
| |
| static int nand_ecc_test(const size_t size) |
| { |
| int err = 0; |
| void *error_data; |
| void *error_ecc; |
| void *correct_data; |
| void *correct_ecc; |
| char testname[30]; |
| |
| error_data = kmalloc(size, GFP_KERNEL); |
| error_ecc = kmalloc(3, GFP_KERNEL); |
| correct_data = kmalloc(size, GFP_KERNEL); |
| correct_ecc = kmalloc(3, GFP_KERNEL); |
| |
| if (!error_data || !error_ecc || !correct_data || !correct_ecc) { |
| err = -ENOMEM; |
| goto error; |
| } |
| |
| sprintf(testname, "nand-ecc-%zu", size); |
| |
| get_random_bytes(correct_data, size); |
| |
| memcpy(error_data, correct_data, size); |
| inject_single_bit_error(error_data, size); |
| |
| __nand_calculate_ecc(correct_data, size, correct_ecc); |
| __nand_calculate_ecc(error_data, size, error_ecc); |
| __nand_correct_data(error_data, correct_ecc, error_ecc, size); |
| |
| if (memcmp(correct_data, error_data, size)) { |
| pr_err("mtd_nandecctest: not ok - %s\n", testname); |
| dump_data_ecc(error_data, error_ecc, correct_data, correct_ecc, |
| size); |
| err = -EINVAL; |
| goto error; |
| } |
| pr_info("mtd_nandecctest: ok - %s\n", testname); |
| error: |
| kfree(error_data); |
| kfree(error_ecc); |
| kfree(correct_data); |
| kfree(correct_ecc); |
| |
| return err; |
| } |
| |
| #else |
| |
| static int nand_ecc_test(const size_t size) |
| { |
| return 0; |
| } |
| |
| #endif |
| |
| static int __init ecc_test_init(void) |
| { |
| int err; |
| |
| err = nand_ecc_test(256); |
| if (err) |
| return err; |
| |
| return nand_ecc_test(512); |
| } |
| |
| 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"); |