Jio Information; C.4.2 Jio Information - Sun Microsystems Blade 1500 Service, Diagnostics, And Troubleshooting Manual

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Four TransIDs per Device ID
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Optional dead cycle for bus turnaround
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C.4.2

JIO Information

The Sun Blade 1500 workstation uses the JIO I/O bridge as the bridge from the JBus
to the PCI buses. JIO is a companion core-logic ASIC to the UltraSPARC IIIi CPU.
The I/O bridge and UltraSPARC IIIi communicate through JBus. The central task of
I/O bridge is to be the point of access to I/O, and system interrupts.
C.4.2.1 Key Features
The following are key features of the JIO:
JBus interface
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Two 64-bit/66MHz PCI leafs
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I/O cache (8 x 64-bytes)
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I/O MMU
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Mondo dispatch unit
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Byte twisting
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C.4.2.2 JIO Block Diagram
FIGURE C-5
C-16 Sun Blade 1500 Service, Diagnostics, and Troubleshooting Manual • December 2004
Out-of-order data return for different cache addresses. In-order data return
from single noncacheable port. In-order data return for same cacheable
address. Order determined by address bus order.
Out-of-order data return values are according to the address bus order. Data
return implies completion of prior coherency events, by the requestor, which is
a minimal requirement, but also by all other ports, implicitly.
One per leaf
Fully associative
In JBus coherency space
One per leaf
Fully associative TLB
shows the block diagram for the JIO I/O bridge.