ref: c655b6552cae96cc174549f07d55c0255d246615
dir: /sys/src/9/port/nandecc.h/
typedef enum NandEccError {
NandEccErrorBad,
NandEccErrorGood,
NandEccErrorOneBit,
NandEccErrorOneBitInEcc,
} NandEccError;
ulong nandecc(uchar buf[256]);
NandEccError nandecccorrect(uchar buf[256], ulong calcecc, ulong *storedecc,
int reportbad);