MPC563XM Reference Manual, Rev. 1
Freescale Semiconductor
203
Preliminary—Subject to Change Without Notice
Chapter 10
Flash Memory (C90FL)
1
10.1
Introduction
This section presents information about the following components on this device:
•
C90FL PFlash memory controller
•
C90FL flash memory block
10.2
Platform Flash (PFlash) Memory Controller
10.2.1
Controller Overview
The PFlash Memory Controller supports a 64-bit data bus width at the crossbar port, and a 128-bit read
data interface from the flash memory array. The PFlash Memory Controller contains a four-entry prefetch
buffer, each entry containing 128 bits of data, and an associated controller which prefetches sequential
lines of data from the flash array into the buffer. Prefetch buffer hits support zero-wait crossbar data phase
responses. Crossbar read requests which miss the buffers generate the needed flash array access and are
forwarded to the crossbar upon completion, typically incurring two wait-states at the maximum operating
frequency.
The PFlash Memory Controller memory controller is optimized for applications where a cacheless
processor core, e.g., Z3 or ARM7, is connected through the Standard Product Platform to on-chip
memories, e.g., flash and SRAM, where the processor and platform operate at the same frequency. For
these applications, the 2-stage pipeline AMBA-AHB system bus is effectively mapped directly into stages
of the processor’s pipeline and zero wait-state responses for most memory accesses is critical for providing
an acceptable level of system performance.
10.2.2
Features
The following list summarizes the key features of the PFlash Memory Controller:
•
System bus interface supports a 64-bit data bus. All aligned and unaligned reads within the
32/64-bit contained are supported. Only aligned word and doubleword writes are supported.
•
Array interface supports a 128-bit read data bus and a 64-bit write data bus.
•
Provides configurable read buffering and line prefetch support. Four line read buffers (each 128 bits
wide) and a prefetch controller are used to support single-cycle read responses (zero wait-states) for
hits in the buffers. The buffers implement a least-recently-used replacement algorithm to maximize
performance. The nomenclature “page buffers and “line buffers” are used interchangeably.
•
Provides hardware and software configurable read and write access protections on a per-master
basis.
1.This chapter is only valid for the primary version of the MPC5633M, in the future it may use the LC Flash.