MPC8544COMEDEV Freescale Semiconductor, MPC8544COMEDEV Datasheet - Page 322

• Manufacturer Part Number: MPC8544COMEDEV
• Description: KIT DEV EXPRESS MPC8544COM
• Manufacturer: Freescale Semiconductor
• Type: MPUr

Specifications of MPC8544COMEDEV

• Contents: Board
• For Use With/related Products: MPC8544
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

e500 Coherency Module
in EEBPCR register. Depending how the CPU_RD_HI_DIS field in EEBPCR register is set, read
transactions from the e500 core are initially assigned to either the higher- or lower-bandwidth queue of the
DDR target.
8.3.3
The ECM’s transaction queue performs four basic functions: arbitration across the e500 core and I/O
masters, target mapping and dispatching, enforcement of ordering, and enforcement of coherency. The
address of each transaction is compared against each local access window, and the transaction is then
routed to the appropriate target interface associated with the local access window that the address hits
within. Even though the CCB and ECM allow the pipelining of transactions, the address tenures of all
transactions issued from I/O masters (masters other than the e500 core) may still be ordered. For those
transactions accessing address space marked as snoopable, or space that may be cached by the e500 core,
the ECM enforces coherency, snooping those transactions on the CCB, and taking castouts from the e500
core as is necessary.
8.3.4
Figure 8-1
one 128-bit global data bus. The global data mux allows initiators of write transactions to route data to
their targets and read targets to return data to the initiators.
8.3.5
Figure 8-1
address tenures for the ECM transaction queue. It also contains the queueing and buffering needed to
manage outstanding CCB data tenures. The buffers receive e500 core-initiated write and I/O-initiated read
data (that hit in the L2/SRAM module) from the e500 write (128-bit wide) and read (128-bit wide) data
buses and route them through the global data mux to the global data bus. The buffers also receive e500
core-initiated read and I/O-initiated write data (that hit in the L2/SRAM module) from the global data bus
and forward them onto the CCB data bus (64 bits).
8.4
If the e500 core is used to initialize the MPC8544E, the CPU boot configuration power-on reset pin should
be pulled high to initially set EEBPCR[CPU_EN]. See
for more information on power-up reset initialization.
If any device other than the e500 core (such as ) is used to initialize the MPC8544E, the CPU boot
configuration power-on reset pin should be pulled low to initially clear EEBPCR[CPU_EN]. This prevents
the e500 core from accessing any configuration registers or local memory space during initialization.
However, in any such system, one step near the end of the initialization routine must set
EEBPCR[CPU_EN] to re-enable the e500 core. Note that for basic functionality, EEBPCR[CPU_EN] is
the only field that must be written (provided a device other than the e500 core is used to initialize the
device) in the ECM.
8-10
shows how the global data multiplexor takes data bus connections and multiplexes them onto
shows the CCB interface for both CCB address and data tenures. This interface formats CCB
Initialization/Application Information
Transaction Queue
Global Data Multiplexor
CCB Interface
MPC8544E PowerQUICC III Integrated Host Processor Family Reference Manual, Rev. 1
Chapter 4, “Reset, Clocking, and
Freescale Semiconductor
Initialization,”