/**
* \brief Read the data and/or spare of a page of a NAND Flash chip, and verify
* that the data is valid using the ECC information contained in the spare. If
* one buffer pointer is 0, the corresponding area is not saved.
*
* \param ecc Pointer to an nand_flash_ecc instance.
* \param block Number of block to read from.
* \param page Number of page to read inside given block.
* \param data Data area buffer.
* \param spare Spare area buffer.
*
* \return 0 if the data has been read and is valid; otherwise returns either
* NAND_COMMON_ERROR_CORRUPTEDDATA or ...
*/
uint32_t nand_flash_ecc_read_page(const struct nand_flash_ecc *ecc,
uint16_t block, uint16_t page, uint8_t *data, uint8_t *spare)
{
uint32_t error;
uint8_t hamming_code[NAND_COMMON_MAX_SPARE_ECC_BYTES];
uint8_t spare_buffer[NAND_COMMON_MAX_PAGE_SPARE_SIZE];
uint16_t page_data_size
= nand_flash_model_get_page_data_size(MODEL(ecc));
/* if no buffer provided, use a temp one */
if (!spare) {
spare = spare_buffer;
}
memset(spare, 0xFF, NAND_COMMON_MAX_PAGE_SPARE_SIZE);
/* Start by reading the spare and the data */
nand_flash_raw_read_page(RAW(ecc), block, page, data, spare);
/* Retrieve ECC information from page and verify the data */
nand_flash_spare_scheme_read_ecc(nand_flash_model_get_scheme(MODEL(ecc)),
spare, hamming_code);
error = hamming_verify_256x(data, page_data_size, hamming_code);
if (error && (error != HAMMING_ERROR_SINGLE_BIT)) {
return NAND_COMMON_ERROR_CORRUPTEDDATA;
}
return 0;
}
/**
* \brief Reads the data and/or spare of a page of a NANDFLASH chip, and verify that
* the data is valid using the ECC information contained in the spare. If one
* buffer pointer is 0, the corresponding area is not saved.
* \param nand Pointer to an EccNandFlash instance.
* \param block Number of block to read from.
* \param page Number of page to read inside given block.
* \param data Data area buffer.
* \param spare Spare area buffer.
* \return 0 if the data has been read and is valid; otherwise returns either
* NAND_ERROR_CORRUPTEDDATA or ...
*/
static uint8_t ecc_read_page_with_swecc(const struct _nand_flash *nand,
uint16_t block, uint16_t page, void *data, void *spare)
{
uint8_t error;
uint8_t hamming[NAND_MAX_SPARE_ECC_BYTES];
uint16_t page_data_size = nand_model_get_page_data_size(&nand->model);
uint8_t page_spare_size = nand_model_get_page_spare_size(&nand->model);
/* Start by reading the spare data */
error = nand_raw_read_page(nand, block, page, NULL, spare_buf);
if (error) {
trace_error("nand_ecc_read_page: Failed to read page\r\n");
return error;
}
/* Then reading the data */
error = nand_raw_read_page(nand, block, page, data, NULL);
if (error) {
trace_error("nand_ecc_read_page: Failed to read page\r\n");
return error;
}
/* Retrieve ECC information from page and verify the data */
nand_spare_scheme_read_ecc(nand_model_get_scheme(&nand->model),
spare_buf, hamming);
error = hamming_verify_256x(data, page_data_size, hamming);
if (error && (error != HAMMING_ERROR_SINGLEBIT)) {
trace_error("nand_ecc_read_page: at B%d.P%d Unrecoverable data\r\n",
block, page);
return NAND_ERROR_CORRUPTEDDATA;
}
if (spare) {
memcpy(spare, spare_buf, page_spare_size);
}
return 0;
}