37.19.3.1 Error Location

The PMECC Error Location controller provides hardware acceleration for determining roots of polynomials over two finite fields: GF(2^13) and GF(2^14). It integrates 32 fully programmable coefficients. These coefficients belong to GF(2^13) or GF(2^14). The coefficient programmed in PMERRLOC{i} is the coefficient of X ^ i in the polynomial.

The search operation is started as soon as a write access is detected in the PMECC Error Location Enable (HSMC_ELEN) register and can be disabled by writing to the PMECC Error Location Disable (HSMC_ELDIS) register. Initialize HSMC_ELEN.ENINIT with the number of galois field elements to test.

Table 37-17. ENINIT Field Value for a Sector Size of 512 Bytes
Error Correcting Capability	ENINIT Value
2	4122
4	4148
8	4200
12	4252
24	4408
32	4512

Table 37-18. ENINIT Field Value for a Sector Size of 1024 Bytes
Error Correcting Capability	ENINIT Value
2	8220
4	8248
8	8304
12	8360
24	8528
32	8640

While the PMECC engine searches for roots, the BUSY field in the PMECC Error Location Status register (HSMC_ELSR) remains asserted. An interrupt is asserted at the end of the computation, and the DONE bit in the PMECC Error Location Interrupt Status register (HSMC_ELSIR) is set. The HSMC_ELISR.ERR_CNT field shows the number of errors. The PMECC Error Location x registers (HSMC_ERRLOCx) show the error position.