MPC563XM Reference Manual, Rev. 1
284
Freescale Semiconductor
Preliminary—Subject to Change Without Notice
— This setting is similar to the basic stall-while-write capability provided when BKn_RWWC =
0b111 with the added ability to generate a notification interrupt if a read arrives while the array
is busy with a program/erase operation. There are two notification interrupts, one for each
bank.
•
BKn_RWWC = 0b101
— Again, this setting provides the basic stall-while-write capability with the added ability to abort
any program/erase operation if a read access is initiated. For this setting, the read request is
captured and retried as described for the basic stall-while-write, plus the program/erase
operation is aborted by the Flash BIU’s assertion of the
bkn_fl_abort
signal. The
bkn_fl_abort
signal remains asserted until
bkn_fl_done
is driven high. For this setting, there are no
notification interrupts generated.
•
BKn_RWWC = 0b100
— This setting provides the basic stall-while-write capability with the ability to abort any
program/erase operation if a read access is initiated plus the generation of an abort notification
interrupt. For this setting, the read request is captured and retried as described for the basic
stall-while-write, the program/erase operation is aborted by the Flash BIU’s assertion of the
bkn_fl_abort
signal and an abort notification interrupt generated. There are two abort
notification interrupts, one for each bank.
As detailed above, there is a total of four interrupt requests associated with the stall-while-write
functionality. These four interrupt requests are captured as part of MCM’s Interrupt Register and logically
summed together to form a single request to the interrupt controller.
11.7.11 Wait-State Emulation
Emulation of other memory array timings are supported by the Flash BIU on read cycles to the Flash. This
functionality may be useful to maintain the access timing for blocks of memory which were used to overlay
Flash blocks for the purpose of system calibration or tuning during code development.
The Flash BIU inserts additional wait-states according to the values of
haddr[28:24]
. When these inputs
are non-zero, additional cycles are added to AHB read cycles. Write cycles are not affected. In addition,
no page read buffer prefetches are initiated, and buffer hits are ignored.
show the relationship of
haddr[28:24]
to the number of additional primary
wait-states. These wait-states are applied to the initial access of a burst fetch or to single-beat read accesses
on the AHB system bus.
Table 11-27. Flash BIU Stall-While-Write Interrupts
MIR[n]
Interrupt Description
MCM.MIR[7]
Platform Flash bank0 abort notification
MCM.MIR[6]
Platform Flash bank0 stall notification
MCM.MIR[5]
Platform Flash bank1 abort notification
MCM.MIR[4]
Platform Flash bank1 stall notification