Datasheet

Datasheet, Volume 1 13
Introduction
• 64-bit downstream address format, but the processor never generates an address
above 64 GB (Bits 63:36 will always be zeros).
• 64-bit upstream address format, but the processor responds to upstream read
transactions to addresses above 64 GB (addresses where any of Bits 63:36 are
nonzero) with an Unsupported Request response. Upstream write transactions to
addresses above 64 GB will be dropped.
• Re-issues Configuration cycles that have been previously completed with the
Configuration Retry status.
• PCI Express reference clock is 100-MHz differential clock.
• Power Management Event (PME) functions.
• Static lane numbering reversal. Land CFG[3] should be pulled down if lane reversal
is desired (refer to Table 6-5).
• Dynamic frequency change capability (2.5 GT/s - 5.0 GT/s)
• Dynamic width capability
• Message Signaled Interrupt (MSI and MSI-X) messages
• Polarity inversion
1.2.3 Direct Media Interface (DMI)
• Four lanes in each direction.
• 2.5 GT/s point-to-point DMI interface to PCH is supported.
• Raw bit-rate on the data pins of 2.5 GB/s, resulting in a real bandwidth per pair of
250 MB/s given the 8b/10b encoding used to transmit data across this interface.
Does not account for packet overhead and link maintenance.
• Maximum theoretical bandwidth on interface of 1 GB/s in each direction
simultaneously, for an aggregate of 2 GB/s when DMI x4.
• Shares 100-MHz PCI Express reference clock.
• 64-bit downstream address format, but the processor never generates an address
above 64 GB (Bits 63:36 will always be zeros).
• 64-bit upstream address format, but the processor responds to upstream read
transactions to addresses above 64 GB (addresses where any of Bits 63:36 are
nonzero) with an Unsupported Request response. Upstream write transactions to
addresses above 64 GB will be dropped.
• Supports the following traffic types to or from the PCH
—DMI -> DRAM
— DMI -> processor core (Virtual Legacy Wires (VLWs), Resetwarn, or MSIs only)
— Processor core -> DMI
• APIC and MSI interrupt messaging support
— Message Signaled Interrupt (MSI and MSI-X) messages
• Downstream SMI, SCI, and SERR error indication
• Legacy support for ISA regime protocol (PHOLD/PHOLDA) required for parallel port
DMA, floppy drive, and LPC bus masters
• DC coupling – no capacitors between the processor and the PCH
• Polarity inversion
• PCH end-to-end lane reversal across the link
• Supports Half Swing “low-power/low-voltage” and Full Swing “high-power/high-
voltage” modes