LS1046A IFC NOR and GPCM settings

[sep]

The 1.4.9 Integrated flash controller in ls1046a Reference Manual shows that NOR and GPCM support 256MB.

However, the IFC Address only exists from 0 to 27, and when calculated, it is confirmed that only 32MByte can be set.

How do I design it to set 256MByte that is confirmed in the Reference Manual?

[yipingwang]

The number of address lines in a system determines the maximum addressable memory space of that system. With 28 address lines, the IFC can address up to 2^28 (268,435,456) unique memory locations. In the case of NOR flash, each memory location typically consists of 1 byte (8 bits).
Therefore, the maximum memory space that can be addressed by the IFC is 268,435,456 bytes (or 256 megabytes).

[sep]

If I use 16-bit NOR-flash, is Address[27] unused?

Calculated in 16-bit NOR-flash, the maximum is 512 Mbyte, but LS1046A data sheet checks indicate that it supports up to 256 Mbyte.

[yipingwang]

As stated in the reference manual, an IFC with 28 address lines and a data bus width of 16 bits supports memory banks of up to 256 MB for NOR and GPCM.
If you use 16-bit NOR flash, then in that case, the address line A[0] will be masked.