Chapter 3. Address Maps
3-13
Address Translation
3.3.2 Outbound PCI Address Translation
For outbound translation, an outbound memory window is specified in the upper 2 Gbytes
of the MPC8240’s address space, and an outbound translation window is specified in the
PCI memory space. Processor and DMA transactions that fall within the outbound memory
window are forwarded to the PCI bus with the address translated to the outbound translation
window. Outbound transaction addresses outside of the outbound memory window are
forwarded to the PCI bus untranslated.
Figure 3-7 shows outbound PCI address translation from the processor core address space
to PCI memory space.
Figure 3-7. Outbound PCI Address Translation
Transactions to the MPC8240 address space marked as configuration address,
configuration data, and interrupt acknowledge (0xFEC0_0000–0xFEFF_FFFF) are
excluded from the outbound memory window. If the outbound memory base address is set
to include this range, the MPC8240 will not translate the accesses to the outbound
translation window. That is, the range appears as a hole in the outbound translation.
PCI memory space
Local memory space
0
4G
PCI memory space
Host memory space
0
4G
PCI Memory Space
Outbound translation
Outbound memory
window
Outbound address
translation
window
Outbound translation
Outbound memory
base address
Transactions outside the
TOM
2G
4G - 20M
4G - 16M
Outbound
base address
outbound memory
window are forwarded
without translation
window size
Processor
View
Summary of Contents for MPC8240
Page 1: ...MPC8240UM D Rev 1 1 2001 MPC8240 Integrated Processor User s Manual ...
Page 38: ...xviii MPC8240 Integrated Processor User s Manual TABLES Table Number Title Page Number ...
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 ...