Intel SE7520JR2 Computer Hardware User Manual


 
Intel® Server Board SE7520JR2 Functional Architecture
Revision 1.0
C78844-002
53
Both PCI and IRQ types of interrupts are handled by the ICH5-R. The ICH5-R translates these
to the APIC bus. The numbers in the table below indicate the ICH5-R PCI interrupt input pin to
which the associated device interrupt (INTA, INTB, INTC, INTD) is connected. The ICH5-R I/O
APIC exists on the I/O APIC bus with the processors.
Table 9: PCI Interrupt Routing/Sharing
Interrupt INT A INT B INT C INT D
Video ICH5R_PIRQB
IDE RAID ICH5R_PIRQC
NIC 10/100 (Not used on
SE7520JR2)
ICH5R_PIRQD
SIO ICH5R_SERIRQ
Legacy IDE ICH5R_PIRQ14
Legacy IDE ICH5R_PIRQ15
82546GB #1 P64A_IRQ6
82546GB #2 P64A_IRQ7
SCSI Controller #1 P64B_IRQ2
SCSI Controller #2 P64B_IRQ1
FL Riser TCK & TCO P64A_IRQ0 P64A_IRQ3 P64A_IRQ5 P64A_IRQ4
P64-A Slot 1 P64A_IRQ0 P64A_IRQ3 P64A_IRQ5 P64A_IRQ4
P64-A Slot 2 P64A_IRQ3 P64A_IRQ5 P64A_IRQ4 P64A_IRQ0
P64-A Slot 3 P64A_IRQ5 P64A_IRQ4 P64A_IRQ2 P64A_IRQ1
LP Riser P64B_IRQ4 P64B_IRQ3 P64B_IRQ2 P64B_IRQ1
P64-B Slot 1 P64B_IRQ4 P64B_IRQ3 P64B_IRQ2 P64B_IRQ1
P64-B Slot 2 P64B_IRQ3 P64B_IRQ2 P64B_IRQ1 P64B_IRQ4
P64-B Slot 3 P64B_IRQ2 P64B_IRQ1 P64B_IRQ4 P64B_IRQ3
3.4.3.2 APIC Interrupt Routing
For APIC mode, the Server Board SE7520JR2 interrupt architecture incorporates three Intel I/O
APIC devices to manage and broadcast interrupts to local APICs in each processor. The Intel
I/O APICs monitor each interrupt on each PCI device including PCI slots in addition to the ISA
compatibility interrupts IRQ(0-15). When an interrupt occurs, a message corresponding to the
interrupt is sent across a three-wire serial interface to the local APICs. The APIC bus minimizes
interrupt latency time for compatibility interrupt sources. The I/O APICs can also supply greater
than 16 interrupt levels to the processor(s). This APIC bus consists of an APIC clock and two
bidirectional data lines.