User manual

Memory Controller
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 11-3
11.1 Features
The memory controller’s main features are as follows:
• Twelve memory banks
— 32-bit address decoding with mask
— Variable block sizes (32 Kbytes to 4 Gbytes)
— Three types of data errors check/correction:
– Normal odd/even parity
– Read-modify-write (RMW) odd/even parity for single accesses
–ECC
— Write-protection capability
— Control signal generation machine selection on a per-bank basis
— Flexible chip-select assignment between the 60x bus and the local bus
— Supports internal or external masters on the 60x bus
— Data buffer controls activated on a per-bank basis
— Atomic operation
— Extensive external memory-controller/bus-slave support
— ECC/parity byte-select
— Data pipeline to reduce data setup time for synchronous devices
• Synchronous DRAM machine (60x or local bus)
— Provides the control functions and signals for glueless connection to JEDEC-compliant
SDRAM devices
— Back-to-back page mode for consecutive, back-to-back accesses
— Supports 2-, 4- and 8-way bank interleaving
— Supports SDRAM port size of 64-bit (60x only), 32-bit, 16-bit and 8-bit
— Supports external address and/or command lines buffering
• General-purpose chip-select machine (GPCM)—60x or local bus
— Compatible with SRAM, EPROM, FEPROM, and peripherals
— Global (boot) chip-select available at system reset
— Boot chip-select support for 8-, 16-, 32-, and 64-bit devices
— Minimum two clock accesses to external device
— Eight byte write enable signals (WE)—four on the local bus
— Output enable signal (OE
)
— External access termination signal (GTA)
• Three UPMs
— Each machine can be assigned to the 60x or local bus.
— Programmable-array-based machine controls external signal timing with a granularity of up to
one quarter of an external bus clock period