Intel CONTROLLERS 413808 - Manual (Page 282)

Intel
®
413808 and 413812—Address Translation Unit (PCI Express)
Intel ® 413808 and 413812 I/O Controllers in TPER Mode
Developer’s Manual October 2007
282 Order Number: 317805-001US
3.13 Vital Product Data
Vital Product Data (VPD) provides detailed information to the system regarding the
hardware, software and microcode elements of a device. This information may include
Part Number, Serial Number or other detailed information. This information resides on a
non-volatile storage device (i.e., Flash Memory) attached to the 4138xx. In addition
VPD also provides a mechanism for storing information such as performance or failure
data on the device being monitored.
Support of VPD involves the implementation of the VPD Extended Capabilities List Item
in the Primary ATU. The VPD Extended capabilities header consists of four registers, the
“VPD Capability Identifier Register - VPD_Cap_ID” on page 335 , the “VPD Next Item
Pointer Register - VPD_Next_Item_Ptr” on page 335 , the “VPD Address Register -
VPDAR” on page 336 , and the “VPD Data Register - VPDDR” on page 336 .
Scheduled by Intel XScale
®
processor interrupts, the 4138xx may be used to retrieve
or store VPD information through the VPD extended capabilities list item.
Please consult Appendix I of the PCI Local Bus Specification, Revision 2.3 for the
definitions of compliant VPD format.
3.13.1 Configuring Vital Product Data Operation
By default, the 4138xx VPD functionality is not configured for operation. Specifically,
the VPD Extended Capabilities List Item are not discovered during a PCI Express Link
scan and the ATUs VPD interrupt status bit in the “ATU Interrupt Status Register -
ATUISR” on page 329 are masked by the “ATU Interrupt Mask Register - ATUIMR” on
page 332 . The following steps should be followed to properly configure the 4138xx’s
support for VPD:
1. The 4138xx must be strapped to Retry Type 0 Configuration cycles following the
deassertion of P_RST# . Enabling this configuration cycle retry mechanism insures
that the Intel XScale
®
processor can make the VPD Extended Capabilities List Item
visible before the system configures the 4138xx. The configuration retry
mechanism is controlled through bit 2 of the “PCI Configuration and Status Register
- PCSR” on page 327 .
2. When the configuration retry mechanism is strapped enabled as described in step
1, typically, the 4138xx would also be strapped such that the Intel XScale
®
processor would immediately boot following the deassertion of P_RST# (bit 1 of
the PCSR), though this is not required.
3. The Intel XScale
®
processor writes 90H to the “PCI Express Next Item Pointer
Register - PCIE_NXTP” on page 341 . This links the PCI Express Capabilities List
Item to the VPD Capabilities List Item.
4. The Intel XScale
®
processor clears bit 17 of the ATUIMR to enable the ATUs VPD
interrupt status bit.