Automated Gateware Discovery Using Open Firmware

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Automated Gateware DiscoveryUsingOpen Firmware

• A presentation on my research, and aims to
• lay foundation for
• automating gateware detection.
• Presented By
• Shanly Rajan
• Embedded Systems Engineer (SA SKA)
• MSc Student (UCT)
• Supervisors Prof Mike Inggs Dr Marc Welz
• SKA BURSARY CONFERENCE 04 DECEMBER 2009

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Overview

• Gateware Introduction
• Software-FPGA Interaction
• BORPH An overview
• BORPH Trade-offs
• Open Firmware
• U-boot Open Firmware
• Research Status Future Directions
• Conclusion

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Gateware Introduction

• Gateware Berkeley Term for Design logic that
  goes into the FPGA
• Gateware (hardware user designs / bit files)
  programmed on to FPGAs vary in functionality
• Examples of gateware designs in radio astronomy
  environment ( Spectrometer, Correlators, Gain
  blocks etc)
• The ROACH boards being deployed for MeerKAT are
  configured with gateware designs generated from
  the CASPER toolflow (M-S-SG-E)

(M-S-SG-E)
Application Model File
Bit File/ BORPH File
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Software-FPGA Interaction

• Generally gateware implementations on the FPGA
  requires software support to provide the user an
  interface to communicate with the gateware logic.
• Writing software each time to interact with a
  piece of gateware is a time-consuming and
  difficult task.
• Conventional method of software - hardware (FPGA)
  interaction would be writing device drivers to
  operate on a piece of hardware.
• Existing software - FPGA approach BORPH
  (Berkeley Operating System for Re Programmable
  Hardware).

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BORPH An overview

• An Operating System framework developed by Hayden
  So for FPGA based reconfigurable computers.
• Gateware images programmed is registered as a HW
  process which interacts with the kernel just like
  any SW process.
• Exports hardware-mapped registers to userspace as
  files (/proc entries).

Generate a BOF File
Read/Write FPGA
Terminate Process
Execute a BOF File
CourtesyBrandon Hamilton
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BORPH TradeOffs

• Performance Constraints Existing approach
  requires system call for each Read/Write
  operation potentially reducing performance.
• Greater Level of Abstraction Complicated designs
  where lots of registers needs to be accessed and
  written, can be simplified with a device driver
  that presents a higher level interface
• (For eg auto-gain control)
• Reuse existing drivers Growing database of
  device drivers unused.

Design Concept
Design Concept
UNIX Process
BORPH Process
System Call
System Call
Device Driver
BOF File System
Hardware Device
FPGA
SW
BORPH
Performance vs Ease of Development
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U-boot Open Firmware

• U-boot, the bootloader for the powerpc
  architecture in ROACH has built-in OF support
• The device-tree layout for u-boot is strongly
  inherited from the definition of the Open
  Firmware IEEE 1275-1994 device-tree
• The observation that gateware implementations on
  FPGA can be treated as pluggable peripherals
  suggests that it can be represented in the device
  tree just like any other physical peripheral
• Conventional/Traditional Method Scheme of
  loading existing device drivers to operate on
  physical peripherals can also be extended to
  gateware images as well.
• The research facilitates the process of
  identifying and operating on gateware images by
  extending the existing infrastructure of probing
  devices in traditional software by using Open
  Firmware.

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Research Status Future Directions

• FDT Implementation Details
• Current Status
• Simple gateware implementations like UART,
  Ethernet, Sound Card needs to be integrated and
  tested with uboot open firmware to establish the
  software-FPGA communication link.
• Future Work
• - Hot pluggability
• - Open Firmware compliant
  initialisation code
• (egTiming Synchronisation infrastructure)

• Probes and appends
• Device tree with the metainfo extends
  device driver database

• Metainformationfile
• Bit Stream

• Uses Clent Interface Calls
• to convert OF FDT to operating systems own format

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Conclusion

• Gateware Introduction
• Software-FPGA Interaction
• BORPH An overview
• BORPH Trade-offs
• Open Firmware
• U-boot Open Firmware
• Research Status Future Directions

Existing Software FPGA Approach
(Use BORPH)
Alternate Approach Considered (EXTENDING DEVICE
TREES)
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Questions

• q

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