5 platform irq routing, Figure 9. irq routing diagram, Platform irq routing – Intel Xeon User Manual
Page 29: Irq routing diagram, System overview, Irq14 and 15 for ide segment, Serirq for siopixrq segment, Pcrirq for the pci-x segment

Intel
®
Xeon™ Processor, Intel
®
E7520 Chipset, Intel
®
6300ESB ICH Development Kit User’s Manual
29
System Overview
5.5
Platform IRQ Routing
shows that the Intel 6300ESB I/O Controller uses these segments:
•
IRQ14 and 15 for IDE segment
•
SERIRQ for SIOPIXRQ segment
•
PCRIRQ for the PCI-X segment
•
PIRQ for the PCI 32/33 segment
A Message Signalled Interrupt (MSI) scheme is used between the MCH and PXH over the PCI
Express bus. The PXH uses PAIRQ for the Channel A interface to PCI-X 64-bit/100 MHz
peripherals and PBIRQ for the Channel B interface to PCI-X 64/133. MSI and Non Maskable
Interrupt (NMI) are connected from the Intel 6300ESB I/O Controller to CPU0 and CPU1. The
platform also supports MSI for maskable and non-maskable interrupts.
Figure 9.
IRQ Routing Diagram
B2940-02
MSI
HI
FSB
PCI-E
PCI-E
PCI-E
NMI
SMI
PBIRQ
PCI-X SLOT
REQ/GNT: 0
IDSEL: AD17
A B C D
PAIRQ
0
1
2
3
0
1
2
3
4
5
6
7
PXH
CPU0
PCI-X SLOT
REQ/GNT: 0
IDSEL: AD17
A B C D
PCI-X SLOT
REQ/GNT: 1
IDSEL: AD18
A B C D
PCI-X 64/100
PCI-X 64/133
PCI-X 2.0
PIRQ
PCI-X SLOT
REQ/GNT: 0
IDSEL: AD16
A B C D
PXIRQ
A
B
C
D
A
B
C
D
E
F
G
H
Intel
®
6300ESB
I/O
Controller
Hub
Video
REQ/GNT: 1
IDSEL: AD17
PCI-X 64/66
PCI-X 32/33
NMI
SMI
IDE
IRQ14/15
SERIRQ
MSI
CPU0
NMI
SMI
MSI
NMI
SMI
MSI
SIO
A
PCI-X SLOT
REQ/GNT: 0
IDSEL: AD17
A B C D
PCI-X SLOT
REQ/GNT: 1
IDSEL: AD18
A B C D
FSB
MCH
PCI-E
MSI
MSI
MSI
MSI
HI
MSI
PCI-E
4x
MSI
PCI-E
8x
MSI