Intel SE7501WV2 User Manual

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Intel® Server Board SE7501WV2 TPS 
Configuration and Initialization 
Revision 1.0 
 
 
Intel reference number C25653-001 
39
4.1.3 
System Management Mode Handling 
The Intel
®
 E7501 MCH supports System Management Mode (SMM) operation in standard 
(compatible) mode. System Management RAM (SMRAM) provides code and data storage 
space for the SMI_L handler code, and is made visible to the processor only on entry to SMM, 
or other conditions, which can be configured using Intel E7501 PCI registers. 
4.2 I/O 
Map 
The SE7501WV2 allows I/O addresses to be mapped to the processor bus or through 
designated bridges in a multi-bridge system. Other PCI devices, including the ICH3-S, have 
built-in features that support PC-compatible I/O devices and functions, which are mapped to 
specific addresses in I/O space. On the SE7501WV2 server board, the ICH3-S provides the 
bridge to ISA functions through the LPC bus. 
4.3  Accessing Configuration Space 
All PCI devices contain PCI configuration space, accessed using mechanism #1 defined in the 
PCI Local Bus Specification.  
If dual processors are used, only the processor designated as the Boot-strap Processor (BSP) 
should perform PCI configuration space accesses. Precautions should be taken to guarantee 
that only one processor performs system configuration. 
When CONFIG_ADDRESS is written to with a 32-bit value (selecting the bus number, device on 
the bus, and specific configuration register in the device), a subsequent read or write of 
CONFIG_DATA initiates the data transfer to/from the selected configuration register. Byte 
enables are valid during accesses to CONFIG_DATA; they determine whether the configuration 
register is being accessed or not. Only full Dword reads and writes to CONFIG_ADDRESS are 
recognized as a configuration access by the Intel chipset. All other I/O accesses to 
CONFIG_ADDRESS are treated as normal I/O transactions. 
4.3.1 CONFIG_ADDRESS 
Register 
CONFIG_ADDRESS is 32 bits wide and contains the field format shown in the following figure. 
Bits [23::16] choose a specific bus in the system. Bits [15::11] choose a specific device on the 
selected bus. Bits [10:8] choose a specific function in a multi-function device. Bit [8::2] select a 
specific register in the configuration space of the selected device or function on the bus.