Chapter 3. Address Maps
3-1
Chapter 3
Address Maps
The MPC8240 in PCI host mode supports two address mapping configurations designated
as address map A, and address map B. The address map is selected at reset by the MAA0
configuration pin. The address map selected at reset is stored as the initial value of the
PICR1[ADDRESS_MAP] bit. If the MPC8240 is configured as a PCI host and the address
map configuration pin is pulled low, the MPC8240 uses address map A. If the MPC8240 is
configured as a PCI host and the address map configuration pin is pulled high, the
MPC8240 uses address map B.
If the MPC8240 is configured as a PCI agent, it must be configured to use address map B.
In agent mode, the MPC8240 offers address translation capability to allow address
remapping for inbound and outbound PCI memory transactions. Translation allows a
certain address space to map to a window of physical memory.
The MAA1 reset configuration pin selects whether the MPC8240 is operating as a PCI host
or agent. For more information on the reset configuration signals, see Section 2.4,
“Configuration Signals Sampled at Reset.”
Address map A conforms to the now-obsolete PowerPC reference platform (PReP)
specification. It is strongly recommended that new designs use map B because map A may
not be supported in future devices. For this reason, address map A is not described in this
chapter; instead, it is described in Appendix A, “Address Map A.”
Address map B conforms to the PowerPC microprocessor common hardware reference
platform (CHRP). When the MPC8240 is configured as a PCI agent, only map B is
supported. This chapter describes map B.
The MPC8240 also has a block of local memory and PCI memory space that is allocated to
the control and status registers for several embedded features. This block is called the
embedded utilities memory block (EUMB). The EUMB and its offsets are also described
in this chapter.
3.1 Address Map B
The address space of map B is divided into four areas—local memory, PCI memory, PCI
I/O, and system ROM space. Throughout this chapter, the term local memory is used to
mean that (S)DRAM is directly controlled by the MPC8240 memory controller.
Summary of Contents for MPC8240
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Page 48: ...xlviii MPC8240 Integrated Processor User s Manual Acronyms and Abbreviations ...
Page 312: ...6 94 MPC8240 Integrated Processor User s Manual ROM Flash Interface Operation ...
Page 348: ...7 36 MPC8240 Integrated Processor User s Manual PCI Host and Agent Modes ...
Page 372: ...8 24 MPC8240 Integrated Processor User s Manual DMA Register Descriptions ...
Page 394: ...9 22 MPC8240 Integrated Processor User s Manual I2O Interface ...
Page 412: ...10 18 MPC8240 Integrated Processor User s Manual Programming Guidelines ...
Page 454: ...12 14 MPC8240 Integrated Processor User s Manual Internal Arbitration ...
Page 466: ...13 12 MPC8240 Integrated Processor User s Manual Exception Latencies ...
Page 516: ...16 14 Watchpoint Trigger Applications ...
Page 538: ...B 16 MPC8240 Integrated Processor User s Manual Setting the Endian Mode of Operation ...
Page 546: ...C 8 MPC8240 Integrated Processor User s Manual ...
Page 640: ...INDEX Index 16 MPC8240 Integrated Processor User s Manual ...