Remote Boundary-Scan System Test Control
for the ATCA Standard
Gunnar Carlsson1, David Bäckström2 , Erik Larsson2
1)
Ericsson
Radio Network Development
Sweden
ITC 2005
2)
Linköpings Universitet
Department of Computer Science
Sweden
Slide 1
Outline
Remote Boundary-Scan System Test Control
for the ATCA Standard
Introduction
System Environment
Approach
Demonstration Board
Conclusions
ITC 2005
Slide 2
Introduction
Boundary Scan in Modern Systems
Boundary Scan (BScan) not only used for production
interconnect test of boards
In multiboard systems the test controller and the target
devices may be located on different boards
How to link BScan between controller and target devices?
Natural solution: BScan control and data must be routed
through backplane
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Slide 3
Introduction
Multiboard Systems
Backplane
Application
specific
boards
Shelf
Management
Board
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Slide 4
Introduction
BScan Multidrop
Boundary Scan
Control
Path
Central
Processor
Local
Processor
System Management
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Local
Processor
System BScan
Master/Slave
Local BScan
Master/Slave
A
T
E
Local
Processor
Application Boards
Slide 5
Introduction
Related Work
Several commercial solutions exist how to link BScan in a
backplane environment
National Semiconductor: SCAN Bridge
 Based upon: [D.Bhavsar, ITC´91]
 Addressing boards and modules by using the instruction scan
Texas instruments: Addressable Shadow Port (ASP)
 [L.Whetsel, ITC´92]
 Added shadow protocol used to access boards and modules
ITC 2005
Slide 6
Introduction
Problem Definition
However, some system architectures do not include BScan in
the backplane
The emerging ATCA standard is an example, which will be
increasingly deployed
The purpose of this project is to find a way to manage remote
BScan control in ATCA based systems
ITC 2005
Slide 7
System Environment
ATCA Overview
Advanced Telecommunications Computing Architecture
(ATCA)
Contain design specifications and requirements in the
following areas:





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Mechanical and Dimensions
Power Distribution
Thermal Dissipation
Interfacing and Interconnections
System Management
Slide 8
System Environment
System Management (IPMI)
Intelligent Platform Management Interface (IPMI)
Exposing HW management functions to OS and
Management SW
Provides interface and communications for:
 Monitoring and Logging
 Inventory
 Recovery Control
Allows implementation of additional management
applications within the IPMI framework
ITC 2005
Slide 9
System Environment
System Management (IPMI)
Management Bus (IPMB)
Management
SW/OS
SM
BMC
BMC
Shelf
Management
Board
Application
Board
Application
Board
SM = Shelf Manager
BMC = Baseboard Management Controller
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Slide 10
Payload
FRU LEDs
BMC to scale
Payload
Interface
Temperature
Sensor
Synch & Clock I/F
Update Channel I/F
Bussed
E-Keying
Enables
15
Point-to-Point
E-Keying
Enables
BMC
Controller
Blue
LED
Enable
Bussed
E-Keying
Enables
IPMB-0
Buffers
Hardware Address [7:0]
Power Supply Monitoring
Payload Power Enable
Handle
Switch
Management Power
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Fabric I/F
1
1
Base I/F
16
DC/DC
Converter
Monitor/
Controller
Metallic Test Bus
IPMB-0
Hardware Address
Dual –48V Power
Slide 11
System Environment
Management Bus (IPMB)
Intelligent Platform Management Bus (IPMB)
Based on the two wire serial I2C Bus
 Data transfers up to: 100 kbit/s
 Maximum message size: 32 bytes
All IPMI messaging, including IPMB, uses a
request/response protocol
 All IPMB requests must be answered with an IPMB response
 Requests and Responses are not automatically paired
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Slide 12
Approach
Project Goals
Propose a way to transport BScan data and control using the
IPMB
Propose means how to manage embedded tests in IPMI
The solution should fit in the ATCA/IPMI context
Build a demonstration board to validate the proposed solution
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Slide 13
Approach
New Functionality in IPMI
IPMB
Operator/
Test
Program
SM
BMC
Memory
Memory
Shelf Management
Board
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Components
under test
Application Board
Slide 14
Approach
Commands and Data Format
Command set to interface and control the onboard tests:
 Test management commands:
 LIST, SEND, RECEIVE, DELETE
 Test execution commands:
 RUN
 Test setup commands:
 LINK, OPTIONS
Embedded test data format
 National Semiconductor EVF is an example
 Based on the Serial Vector Format (SVF)
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Slide 15
Approach
Transport of BScan Control and Data
IPMB designed to carry short control and status messages
Extended the IPMB protocol to enable transport of BScan
control and data
 Still follows the rules and requirements set by the standard IPMB protocol
 The SM unit is the requester (master) and the BMC units are the responders
(slaves)
 Mechanisms for dividing larger test files into smaller IPMB packages and reassembling of packages back into test files has been specified and
implemented
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Slide 16
Approach
Transport of BScan Control and Data
Transport times of a 77 kB EVF file on IPMB
Description
Standard IPMB restrictions
Increased max packet size
Fast I2C mode
I2C High speed mode
I2C High speed mode and
Increased max packet size
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Max. packet size I2C Speed
Total transport time
Po + P d
S
T3
32 B
64 B
32 B
32 B
64 B
100 kbit/s
100 kbit/s
400 kbit/s
3.4 Mbit/s
3.4 Mbit/s
11.7 s
8.44 s
2.94 s
0.35 s
0.25 s
Slide 17
Demonstration Board
Demonstration Board
Operator
Interface
SM
Shelf Manager
Board
ITC 2005
Operator
Interface
IPMB
Backplane
BMC
SM
UUT
BSC
Application Board
Slide 18
Demonstration Board
Demonstration Board
Operators
interface
UUT
SM-unit
BMC-unit
BScan
controller
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Slide 19
Conclusions
Easy to add BScan functionality to the ATCA/IPMI context
IPMB suitable to carry BScan control and status
IPMB less suitable to carry large tests due to the limitations
of the standard.
Can be solved using the higher available I2C data transfer
speeds and larger IPMB packet sizes
ITC 2005
Slide 20