Intel
®
81341 and 81342 I/O Processors
December 2007
Developer’s Manual
Order Number: 315037-002US
985
Clocking and Reset—Intel
®
81341 and 81342
19.0
Clocking and Reset
This chapter describes the clocking and reset function of the Intel
®
81341 and 81342
I/O Processors (81341 and 81342).
19.1
Clocking Overview
The 81341 and 81342 contains various internal clocking boundaries. Four PLLs are used
to generate the clocks. One PLL for the PCI Express interface, one for PCI-X interface,
one for Memory Interface and one for everything else. Clock regions 3, 4, and 6 are
driven off the core PLL and are pseudo-synchronous to each other. There are
asynchronous boundaries between regions 1/3, regions 2/3, 6/3, and between
regions 7/3.
Figure 168. Intel
®
81341 and 81342 I/O Processors Clocking Regions Diagram
tex
t
Multi-Port
SRAM Controller
Internal
Bus
Bridge
APB
Bridge
UART x2
GPIO
SMBus
Peripheral
Bus
Interface
Clock Region 3
Clock Region 5
Clock Region 7
Clock
Region 8
ADMA x3
IMU
Clock
Region 1
PCI Express
Interface
(ATUE)
PCI-X
Interface
(ATUX)
Clock
Region 2
PMON
DDR SDRAM
Memory Controller
MU
Intel XScale®
Microarchitecture
512K L2 Cache
I2C x3
UART x2
I2C x3
I2C x3
Clock
Region 4
Interrupt
Controller
Interrupt
Controller
Intel XScale®
Microarchitecture
512K L2 Cache
B6354-01