Presentation given by Dirk Koch (University of Manchester) at the LEGaTO Final Event: Low-Energy Heterogeneous Computing Workshop on 4 September 2020 This event was collocated with FPL 2020

1. 1
Operating Systems for FPGAs
–
Why and How?
Dirk Koch and a great team,
University of Manchester, UK
dirk.koch@manchester.ac.uk

2. 2
FOS – the FPGA Operating System

3. 3
FOS – the FPGA Operating System
ZUCL: pre-built Shells
for Zynq Ultrascale+
with middleware for
running OpenCL
 Comes with compile
scripts (RTL/HLS 
relocatable bitstream
 UltraZed, Ultra96, ZCU 102

4. 4
Resource Elastic FPGA Virtualization (for OpenCL)
 Using aggressive reconfiguration to keep utilization high
 Virtualization in the space-domain
(time-domain fallback, if needed)
FOS – the FPGA Operating System

5. 5
How to deploy FPGAs in datacenters?
Several commercial settings:

6. 6
How to deploy FPGAs in datacenters
 Different development tools, tool versions, progr. models
(HLS or RTL likely not portable)
 Different shell infrastructures
(even if cloud vendors use same
FPGA, memory, or board)
 Different HALs and middleware
 No real abstraction (shell updates  accelerator updates)
 No real cloud principles (elasticity? resource pooling?)
 Hardware security? (applies to single and multi-tenancy)

7. 7
How NOT to deploy FPGAs in a datacenter!
Example AWS:
 Shell interface
 Logical interface is fixed
(AXI buses)
 Physical is not fixed
(exact layout of the shell
and routing
 Creates dependency
 Modules run only with a
specific shell
 Requires shell management
shell
memory
memorymemory
memory
die1
die2
die3

8. 8
How to deploy FPGAs in datacenters!
Example PCIeHLS [FSP 2017]:
 Shell with shared memory
and all I/O interfaces
 Fixed internal AXI interfaces
(clock-domain crossing)
 Modules of different size
 Module bitstream relocation
 BitMan [DATE 2017]
 Module replication
 Independence of shell and
accelerator modules
 Can share memory, I/O
bandwidth, FPGA resources
PCIe
&
2x
DDR3
slot1
slot2
slot3
slot4
slotX

9. 9
How to deploy FPGAs in datacenters!
shell
memorymemory
memory
memory
die1
die2
die3
PCIe
PCIe
&
2x
DDR3
slot1
slot2
slot3
slot4
slotX
Alveoshell

10. 10
 Resource Elasticity
In a networked system
 Load balancing and
load distribution
 System keeps track
about input data and
committed results
 Implements a distributed
checkpointing scheme
(tailored to OpenCL)
resilience
 Also useful for
maintenance/updates
Live Migration

11. 11
11
FPGAs for Datacenters (H2020 ECOSCALE)
ECOSCALE demonstrator fully-populated 1u blade with
32 x Zynq UltraScale+ (ZU9EG with 16GB/node or 512 GB/blade)
www.ecoscale.eu

12. 12
12
FPGAs for Datacenters (H2020 ECOSCALE)
Partial reconfiguration allows moving
compute to data  huge energy savings

13. 13
13
FPGAs for Datacenters (H2020 EuroEXA)
• 2-D integr. chips with custom ASIC (64b-ARM) and 2xVU9P FPGAs
• 300+ VU9Ps (will provide ~1B LUTs, 2M DSPs) www.euroexa.eu

14. 14
FPGADefender Virus Scanning for FPGAs
 Detects probably any kind of self-oscillating circuit
 Scans bitstream encoding (short circuits), high fan-out nets,
wire tapping, module bounding boxes, glitch-amplification,
interfaces to the shell, … (all at bitstream (netlist) level)

15. 15
People:
 Tuan Minh La {tuan.la@postgrad.manchester.ac.uk}
 Anuj Vaishnav {anuj.vaishnav@manchester.ac.uk}
 Khoa Dang Pham {khoa.pham@manchester.ac.uk}
 Kaspar Matas {kaspar.matas@manchester.ac.uk}
 Nikola Grunchevski {nikola.grunchevski@manchester.ac.uk}
 Dirk Koch {dirk.koch@manchester.ac.uk}
FPGADefenderFPGADefender
Secure and Virtualized FPGA Management for FPGAs