4-12
MPC8240 Integrated Processor User’s Manual
PCI Interface Configuration Registers
The 2-byte PCI status register, shown in Figure 4-4, is used to record status information for
PCI bus-related events. The definition of each bit is given in Table 4-6. Only 2-byte
accesses to address offset 0x06 are allowed.
4.2.2 PCI Status Register—Offset 0x06
The 2-byte PCI status register, shown in Figure 4-4, is used to record status information for
PCI bus-related events. The definition of each bit is given in Table 4-6. Only 2-byte
accesses to address offset 0x06 are allowed.
Table 4-5. Bit Settings for PCI Command Register—0x04
Bits
Name
Reset
Value
Description
15–10
—
All 0s
These bits are reserved.
9
Fast back-to-back
0
This bit is hardwired to 0, indicating that the MPC8240 does not run fast
back-to-back transactions.
8
SERR
0
This bit controls the SERR driver of the MPC8240. This bit (and bit 6)
must be set to report address parity errors.
0 Disables the SERR driver
1 Enables the SERR driver
7
—
0
This bit is reserved.
6
Parity error response
0
This bit controls whether the MPC8240 responds to parity errors.
0 Parity errors are ignored and normal operation continues.
1 Action is taken on a parity error. See Chapter 13, “Error Handling,” for
more information.
5
—
0
This bit is reserved.
4
Memory-write-and-
invalidate
0
This bit enables generation of the memory-write-and-invalidate command
by the MPC8240 as a master.
0 Memory-write command used by MPC8240.
1 Memory-write-and-invalidate command used by MPC8240.
3
Special cycles
0
This bit is hardwired to 0, indicating that the MPC8240 (as a target)
ignores all special-cycle commands.
2
Bus master
1 (host)
0 (agent)
This bit controls whether the MPC8240 can act as a master on the PCI
bus. Note that if this bit is cleared, processor-to-PCI writes cause the data
to be held until it is enabled. Processor to PCI reads with master disabled
cause a machine check exception (if enabled).
0 Disables the ability to generate PCI accesses
1 Enables the MPC8240 to behave as a PCI bus master
1
Memory space
0
This bit controls whether the MPC8240 (as a target) responds to memory
accesses.
0 The MPC8240 does not respond to PCI memory space accesses.
1 The MPC8240 responds to PCI memory space accesses.
0
I/O space
0
This bit is hardwired to 0, indicating that the MPC8240 (as a target) does
not respond to PCI I/O space accesses.
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 ...