CA91L8260B Datasheet, PDF (172/439 Pages) Integrated Device Technology – PowerSpan II™ User Manual

172
9. Resets, Clocks and Power-up Options
Table 45: PowerSpan II Power-up Options
Power-up Option
Selection
System Pin^a PB_D Pin^b
RST_CSR Register
PCI-1 REQ64 Enable
(PWRUP_P1_R64_EN)
Disable
P1_REQ64_
Enable
P1_REQ64_
Boot select
PB Boot
(PWRUP_BOOT)
PCI Boot
7400 Mode Enable
Disable
7400_Mode
Enable
(PWRUP_7400_MODE) _{7400_Mode}
PLL Bypass Enable
Disable PLL
Bypass
Enable PLL
(PWRUP_BYPASS_EN) Bypass
INT[4]_=1
INT[4]_=0
INT[3]_=1
INT[3]_=0
INT[2]_=1
INT[2]_=0
INT[1]_=1
INT[1]_=0
PB_D[4]=0 P1_R64_EN=0
PB_D[4]=1 P1_R64_EN=1
PB_D[5]=0 PCI_BOOT=0
PB_D[5]=1 PCI_BOOT=1
PB_D[6]=0 7400_MODE=0
PB_D[6]=1 7400_MODE=1
PB_D[7]=0 BYPASS_EN=0
PB_D[7]=1 BYPASS_EN=1
a. The information in the System Pin column is used when PowerSpan II is in Multiplexed System Pin mode
(see page 173)
b. The information in the PB_D Pin column is used when PowerSpan II is in Configuration Slave mode
(page 175).
The options PWRUP_PB_ARB_EN, PWRUP_P1_ARB_EN, and PWRUP_P2_ARB_EN are used to
select between an external arbiter or a PowerSpan II arbiter for each interface.
PWRUP_PRI_PCI designates either PCI-1 or PCI-2 as being connected to the Primary PCI Interface
segment in the system (see “Primary PCI” on page 31 for more details on Primary PCI Interface
functionality).
When PWRUP_P1_R64_EN is enabled, the PowerSpan II PCI-1 interface drives P1_REQ64# during
assertion of P1_RST# to signal the presence of a 32-bit or
64-bit data path to all agents on the PCI-1 bus segment. This option must only be enabled when
PowerSpan II is the Central Resource in the system.
The option PWRUP_BOOT enables the system designer to control boot from PCI or from the
processor bus. Whether this feature is enabled or disabled is dependent on system requirements (refer
to “Arbitration” on page 137 for more information).
By enabling option PWRUP_BYPASS_EN, all PLLs in the design are bypassed. Typically, this option
must be disabled (PLL in use) in the system.
In the Single PCI PowerSpan II, the following power-up options are not configurable:
• PWRUP_P2_ARB_EN
— no PCI-2 arbiter
PowerSpan II User Manual
80A1010_MA001_09
Integrated Device Technology
www.idt.com