<Phillip or Shobana> Washington University in St. Louis

1
Liquid Architecture

• ltPhillip or Shobanagt Washington University in
  St. Louis
• Apr 26, 2004

2
Agenda

• Motivation
• Architecture
• Results
• Related work
• Epilogue
• Demo
• Thank you!

3
Motivation

4
Architecture LEON Controller
5
Design Approach

• Start with Leon Processor base
• Supplies many of the components that will be
  needed in the end system.
• Soft-core processor
• Memory controller
• General I/O Drivers (for Liquid Architecture
  Project)
• System/Processor Bus (AMBA)
• Develop and Integrate new features
• Control SW
• Modify Boot ROM
• AMBA to SDRAM Controller Adapter
• Control Packet routing (MP3 cpp as base)
• Validation Environment (MP3 Testbench as base)

6
Design Data

• New/Modified Entities
• LEON Controller
• Control LEON access to memory / Start of program
  execution
• LEON Boot ROM
• modified to poll a given memory address at boot
  up
• LEON Memory Controller
• modified to interface with FPX SDRAM
• External Memory Interfaces
• 1 SRAM/SDRAM Interface
• Estimated Size
• Number of LUTs 12,277 (31)
• Number of Slices 7900 (41)
• Number of BlockRAMs 54 (33)
• Synthesis Frequence 30 MHz

7
Control S/W Architecture
Internet
Choose a LEON Config upload the program to
profile
Control Software
FPX
Java Emulator of the H/W (for debugging)
8
Interaction with LEON

• Basic steps for User to interface with
  LEON/SRAM
• Wait for READY message
• Load Program to SRAM
• Send LEON START message
• Wait for DATA message
• Read results from SRAM

9
Control S/W web page
10
S/W Compilation Flow

• Uses LECCS Compiler System
• GCC Based
• Test PROMs used LEON compile scripts
• General compile system developed uses DOS .bat
  compile script
• Compile w/ GCC
• Assemble w/ GAS
• Link w/ LD
• Convert to binary w/ OBJCOPY
• Convert to IP w/ Forth program

11
Compile script

• sparc-rtems-gcc test.c -S
• sparc-rtems-as test.s -o test.o
• sparc-rtems-ld test.o -Ttext 0x0 -Tdata 0x1000
  -Tbss 0x2000
• sparc-rtems-objcopy a.out -O binary a.bin
• \gforth0.6.2\gforth tobin.fs gt \class\leon2\input_
  ip.dat

12
Results

• Statistics for LEON cache hits and misses of a
  benchmark application
• Improvement in performance of that app resulting
  from dynamic reconfiguration

13
References Related Work

• The base Leon system http//www.gaisler.com/downlo
  ad.html
• Other projects that have used the Leon system
• http//www.gaisler.com/leon.htmlleonlinks

14
Epilogue

• Conclusion
• Ongoing work
• Acknowledgements
• ltPhillip/ Shobanagt, Scott Friedman, Ben, Huakai
  Zhang, Dr.Cytron, Dr.Lockwood, Dr.Chamberlain,
  Dr.Fritts
• NSF
• More info
• http//www.arl.wustl.edu/arl/projects/fpx/projects
  /liquid_arch/index.htm
• The Demo