Nick: heijligen
E-mail: none
Board: unknown
Contents: 
                  |_region______________________|
                  |########          # # # # # #| # pages to erase
+-----+-----+-----+-----+-----+-----+-----+-----+
| 32K | 32K | 32K | 32K | 32K | 32K | 32K | 32K | erase_fn_0
+-----+-----+-----+-----+-----+-----+-----+-----+
|    64K    |    64K    |    64K    |    64K    | erase_fn_1
+-----------+-----------+-----------+-----------+
|                      256K                     | erase_fn_2
+-----------------------------------------------+

We can't ues `erase_fn_2`, it's outside of the region boundaries.
We can't use `erase_fn_1` for the first pages to erase, because
  it is outside of the boundaries.

The best solution would be:
  erase_fn_0(3);
  erase_fn_0(4)
  erase_fn_1(3)