Automated gateware discovery using Open Firmware

Automated gateware discovery using
Open Firmware
Shanly Rajan
Embedded systems & software engineer (SA SKA)
MSc Student (UCT)
6th SKA SA postgraduate bursary conference
shanly.rajan@ska.ac.za
23rd November 2011
Modular Hardware
2009
RHINO
ROACH
(Reconfigurable
Hardware Interface
for computiNg and radiO)
2010
(Reconfigurable
Open Architecture
Computing Hardware)
ROACH 2
2011
What is an FPGA?
 FPGAs are programmable logic
elements – bread-boards on a chip
that can have their circuits reconfigured
to perform specific tasks very efficiently
ß
 FPGAs can be reconfigured
many times with different function
 FPGA needs to be programmed with
hardware logic to make it meaningful
Modular Gateware
I
N
S
T
R
U
M
E
N
T
S
Acknowledgment: CASPER
GATE WARE
What is Gateware?
Gateware - Berkeley coined term
“Design logic that goes into the FPGA”
Gateware contains registers, memory, LUTs.
MSSGE Toolchain - (Matlab,Simulink,SysGen,Edk)
Bit File/
Bof File
FPGA
Gateware
Hardware
Need for Software Support
Each gateware design implementation/instrument requires
software support (Meaningful)
Changing personalities on FPGA require software to be
written each time (Time Consuming)
Investigation on a mechanism that facilitates the process of
gateware detection (Research)
Modular Software
BORPH (Berkeley Operating System for Reconfigurable Hardware)
OS for evolving modular hardware (ibobs, BEE2s, ROACHs)
Presents a file system of hardware registers to userspace
Performance limitations
Linux OS with FDT(Flattened Device Tree) support
Advantage of latest kernel and driver development
Use device trees and device drivers
Parameterization
What this research provides?
A research framework
which uses Open Firmware
to describe FPGA designs
to facilitate their detection by the operating system
to operate these designs using conventional device
drivers
Design Choices
Framework
Open Firmware
Platform
ROACH
Bootloader: Uboot
PowerPC Linux Kernel
(Supported bootloader and kernels)
CPU
Power PC
More about Open Firmware
Open Firmware : Hardware Independent Boot Code
Boot time drivers for testing machine hardware
Building device trees which OS later uses
Device Tree : Data Structure that holds information about set
of devices attached to a system, including permanently
installed devices and plug-in devices, as described by Open
Firmware
In short we have
• Data structure for describing
hardware / gateware
• Passed to kernel at boot time
OF Device Tree Model
 Tree with nodes & properties
 Nodes give structure
 Properties add detail
root
platform
spi
bridge
uart
Drivers registered
against bus types
i2c bus
temp
pci bus
platform_bus_type
ethernet
i2c_bus_type
pci_bus_type
Acknowledgment:Grant Labs
Overall System Architecture
Research Concept (DDO)
DDO - Describe, Detect and Operate
pluggable
peripherals
Can be treated
Uboot Open Firmware
Device Drivers
Device Tree
Linux
Kernel
Can be represented
Add Me?
Gateware
Images
Conventional Method
Device Database Extension
Serial UART Example
Serial UART Example
1st Case:
We describe a device in the device tree and use
existing linux kernel device drivers
to operate on the device
Serial UART Example
Serial Device
Uartlite Serial Bit
Device Driver
Operates
Uartlite Driver
FPGA
Description
FPGAV5 : serial@d0010000{
device_type = "serial";
compatible = "xlnx,opb-uartlite-1.00.b";
reg = <0xd0010000 10000>;
current-speed = <115200>;
clock-frequency = <66666666>;
xlnx,data-bits = <8>;
xlnx,odd-parity = <0>;
xlnx,use-parity = <0>;
};
Extending device trees
Detect
(Invokes Match)
Treating katADC as a soundcard
Use katADCs to capture data into Block RAMS
with a modified sound device driver
and utilize sound analysis tools for
visualization and playback
Treating katADC as a soundcard
2nd Case
We describe device in device tree and
write a modified / custom device driver to
operate on the device
but use existing audio applications
for gain adjustment and recording
Use kat
wit
an
Treating katADC as a soundcard
2nd Case
We describe device in device tree and
write a modified / custom device driver to
operate on the device
but use existing audio applications
for gain adjustment and recording
•Modified audio device driver
•Adjusted gain using aumix audio
application and observed the change
Use kat
wit
an
Advantages & Future work
Advantages
Future Work
Alternative approach for
software-FPGA interaction
Hot pluggability (Kernel
hotplug)
Reduces time and effort
spent on writing software
for each piece of
gateware generated
Gateware resident
initialisation code
(Device Driver)
Performance benefit
Radio instruments
device drivers
Conclusion
Open Firmware Infrastructure extended to include suitably
designed gateware images
Described gateware in device tree, verified detection and
loading of appropriate device driver by linux OS.
This research work provides a parameterized interface
that can be integrated into
the meerKAT digital backend software
CASPER COLLABORATION
2011, India
THANK YOU
Supervisors: Prof Mike Inggs
Dr Marc Welz
SKA/KAT