If the region is marked as unmapped, o targets EMIF internal registers or reserved space, access is blocked and an error response is returned. Such an error occurs on the first half of a potential split access and aborts the entire access at that time. DECERR errors ultimately generate Arm aborts. See the Arm Fault Status Register for more information.
To avoid undefined results, the following program rules must be followed:
- A section cannot be mapped as interleaving (MA_LISA_MAP_i[9:8] SDRC_MAP = 0x3), and the MA_LISA_MAP_i[19:18] SDRC_INTL bit field must be equal to 0x0.
- If the section maps to a single EMIF (MA_LISA_MAP_i[9:8] SDRC_MAP = 0x1 or 0x2), the MA_LISA_MAP_i[7:0] SDRC_ADDR bit field must be aligned to the MA_LISA_MAP_i[22:20] SYS_SIZE bit field (that is, the lower SDRC_ADDR bits must be 0).
- If the section maps to both EMIFs (MA_LISA_MAP_i[9:8] SDRC_MAP = 0x3), the MA_LISA_MAP_i[7:0] SDRC_ADDR bit field must be aligned to MA_LISA_MAP_i[22:20] SYS_SIZE – 1, because the addressable space for each EMIF is half.
- If the section maps to both EMIFs (MA_LISA_MAP_i[9:8] SDRC_MAP = 0x3), the MA_LISA_MAP_i[22:20] SYS_SIZE bit field cannot be 0.