<s>
OpenRISC	B-Device
is	O
a	O
project	O
to	O
develop	O
a	O
series	O
of	O
open-source	O
hardware	O
based	O
central	B-General_Concept
processing	I-General_Concept
units	I-General_Concept
(	O
CPUs	O
)	O
on	O
established	O
reduced	B-Architecture
instruction	I-Architecture
set	I-Architecture
computer	I-Architecture
(	O
RISC	B-Architecture
)	O
principles	O
.	O
</s>
<s>
It	O
includes	O
an	O
instruction	B-General_Concept
set	I-General_Concept
architecture	I-General_Concept
(	O
ISA	O
)	O
using	O
an	O
open-source	O
license	O
.	O
</s>
<s>
The	O
first	O
(	O
and	O
only	O
)	O
architectural	O
description	O
is	O
for	O
the	O
OpenRISC	B-Device
1000	O
(	O
"	O
OR1k	B-Device
"	O
)	O
,	O
describing	O
a	O
family	O
of	O
32-bit	O
and	O
64-bit	B-Device
processors	I-Device
with	O
optional	O
floating-point	B-Algorithm
arithmetic	I-Algorithm
and	O
vector	B-Operating_System
processing	I-Operating_System
support	O
.	O
</s>
<s>
The	O
OpenRISC	B-Device
1200	I-Device
implementation	O
of	O
this	O
specification	O
was	O
designed	O
by	O
Damjan	O
Lampret	O
in	O
2000	O
,	O
written	O
in	O
the	O
Verilog	B-Language
hardware	O
description	O
language	O
(	O
HDL	O
)	O
.	O
</s>
<s>
The	O
later	O
mor1kx	O
implementation	O
,	O
which	O
has	O
some	O
advantages	O
compared	O
to	O
the	O
OR	O
1200	O
,	O
was	O
designed	O
by	O
Julius	O
Baxter	O
and	O
is	O
also	O
written	O
in	O
Verilog	B-Language
.	O
</s>
<s>
Additionally	O
software	O
simulators	O
exist	O
,	O
which	O
implement	O
the	O
OR1k	B-Device
specification	O
.	O
</s>
<s>
The	O
hardware	O
design	O
was	O
released	O
under	O
the	O
GNU	B-Application
Lesser	I-Application
General	I-Application
Public	I-Application
License	I-Application
(	O
LGPL	B-Application
)	O
,	O
while	O
the	O
models	O
and	O
firmware	O
were	O
released	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
(	O
GPL	B-License
)	O
.	O
</s>
<s>
A	O
reference	O
system	B-Architecture
on	I-Architecture
a	I-Architecture
chip	I-Architecture
(	O
SoC	O
)	O
implementation	O
based	O
on	O
the	O
OpenRISC	B-Device
1200	I-Device
was	O
developed	O
,	O
named	O
the	O
OpenRISC	B-Device
Reference	O
Platform	O
System-on-Chip	B-Architecture
(	O
ORPSoC	O
)	O
.	O
</s>
<s>
Several	O
groups	O
have	O
demonstrated	O
ORPSoC	O
and	O
other	O
OR1200	B-Device
based	O
designs	O
running	O
on	O
field-programmable	B-Architecture
gate	I-Architecture
arrays	I-Architecture
(	O
FPGAs	B-Architecture
)	O
,	O
and	O
there	O
have	O
been	O
several	O
commercial	O
derivatives	O
produced	O
.	O
</s>
<s>
Later	O
SoC	O
designs	O
,	O
also	O
based	O
on	O
an	O
OpenRisc	B-Device
1000	O
CPU	O
implementation	O
,	O
are	O
minSoC	O
,	O
OpTiMSoC	O
and	O
MiSoC	O
.	O
</s>
<s>
The	O
instruction	B-General_Concept
set	I-General_Concept
is	O
a	O
reasonably	O
simple	O
MIPS	O
architecture-like	O
traditional	O
RISC	B-Architecture
using	O
a	O
3-operand	O
load-store	O
architecture	O
,	O
with	O
16	O
or	O
32	O
general-purpose	O
registers	O
and	O
a	O
fixed	O
32-bit	O
instruction	O
length	O
.	O
</s>
<s>
The	O
instruction	B-General_Concept
set	I-General_Concept
is	O
mostly	O
identical	O
between	O
the	O
32	O
-	O
and	O
64-bit	B-Device
versions	O
of	O
the	O
specification	O
,	O
the	O
main	O
difference	O
being	O
the	O
register	O
width	O
(	O
32	O
or	O
64	B-Device
bits	I-Device
)	O
and	O
page	O
table	O
layout	O
.	O
</s>
<s>
The	O
OpenRISC	B-Device
specification	O
includes	O
all	O
features	O
common	O
to	O
modern	O
desktop	O
and	O
server	O
processors	O
:	O
a	O
supervisor	O
mode	O
and	O
virtual	O
memory	O
system	O
,	O
optional	O
read	O
,	O
write	O
,	O
and	O
execute	O
control	O
for	O
memory	O
pages	O
,	O
and	O
instructions	O
for	O
synchronizing	O
and	O
interrupt	O
handling	O
between	O
multiple	O
processors	O
.	O
</s>
<s>
Another	O
notable	O
feature	O
is	O
a	O
rich	O
set	O
of	O
single	B-Device
instruction	I-Device
,	I-Device
multiple	I-Device
data	I-Device
(	O
SIMD	B-Device
)	O
instructions	O
intended	O
for	O
digital	B-General_Concept
signal	I-General_Concept
processing	I-General_Concept
.	O
</s>
<s>
Most	O
implementations	O
are	O
on	O
field-programmable	B-Architecture
gate	I-Architecture
arrays	I-Architecture
(	O
FPGAs	B-Architecture
)	O
which	O
give	O
the	O
possibility	O
to	O
iterate	O
on	O
the	O
design	O
at	O
the	O
cost	O
of	O
performance	O
.	O
</s>
<s>
By	O
2018	O
,	O
the	O
OpenRISC	B-Device
1000	O
was	O
considered	O
stable	O
,	O
so	O
ORSoC	O
(	O
owner	O
of	O
OpenCores	O
)	O
began	O
a	O
crowdfunding	O
project	O
to	O
build	O
a	O
cost-efficient	O
application-specific	O
integrated	O
circuit	O
(	O
ASIC	O
)	O
to	O
get	O
improved	O
performance	O
.	O
</s>
<s>
Several	O
commercial	O
organizations	O
have	O
developed	O
derivatives	O
of	O
the	O
OpenRISC	B-Device
1000	O
architecture	O
,	O
including	O
the	O
ORC32-1208	O
from	O
ORSoC	O
and	O
the	O
BA12	O
,	O
BA14	O
,	O
and	O
BA22	O
from	O
Beyond	O
Semiconductor	O
.	O
</s>
<s>
Dynalith	O
Systems	O
provide	O
the	O
iNCITE	O
FPGA	B-Architecture
prototyping	O
board	O
,	O
which	O
can	O
run	O
both	O
the	O
OpenRISC	B-Device
1000	O
and	O
BA12	O
.	O
</s>
<s>
Flextronics	O
(	O
Flex	O
)	O
and	O
Jennic	O
Limited	O
manufactured	O
the	O
OpenRISC	B-Device
as	O
part	O
of	O
an	O
application-specific	O
integrated	O
circuit	O
(	O
ASIC	O
)	O
.	O
</s>
<s>
Samsung	O
uses	O
the	O
OpenRISC	B-Device
1000	O
in	O
their	O
DTV	O
system-on-chips	O
(	O
SDP83	O
B-Series	O
,	O
SDP92	O
C-Series	O
,	O
SDP1001/SDP1002	O
D-Series	O
,	O
SDP1103/SDP1106	O
E-Series	O
)	O
.	O
</s>
<s>
Allwinner	O
Technology	O
are	O
reported	O
to	O
use	O
an	O
OpenRISC	B-Device
core	O
in	O
their	O
AR100	O
power	O
controller	O
,	O
which	O
forms	O
part	O
of	O
the	O
A31	O
ARM-based	O
SoC	O
.	O
</s>
<s>
Cadence	O
Design	O
Systems	O
have	O
begun	O
using	O
OpenRISC	B-Device
as	O
a	O
reference	O
architecture	O
in	O
documenting	O
tool	O
chain	O
flows	O
(	O
for	O
example	O
the	O
UVM	O
reference	O
flow	O
,	O
now	O
contributed	O
to	O
Accellera	O
)	O
.	O
</s>
<s>
TechEdSat	O
,	O
the	O
first	O
NASA	O
OpenRISC	B-Device
architecture	O
based	O
Linux	B-Operating_System
computer	O
launched	O
in	O
July	O
2012	O
,	O
and	O
was	O
deployed	O
in	O
October	O
2012	O
to	O
the	O
International	O
Space	O
Station	O
with	O
hardware	O
provided	O
,	O
built	O
,	O
and	O
tested	O
by	O
ÅAC	O
Microtec	O
and	O
ÅAC	O
Microtec	O
North	O
America	O
.	O
</s>
<s>
Being	O
open	O
source	O
,	O
OpenRISC	B-Device
has	O
proved	O
popular	O
in	O
academic	O
and	O
hobbyist	O
circles	O
.	O
</s>
<s>
For	O
example	O
,	O
Stefan	O
Wallentowitz	O
and	O
his	O
team	O
at	O
the	O
Institute	O
for	O
Integrated	O
Systems	O
at	O
the	O
Technische	O
Universität	O
München	O
have	O
used	O
OpenRISC	B-Device
in	O
research	O
into	O
multi-core	B-Architecture
processor	I-Architecture
architectures	O
.	O
</s>
<s>
The	O
Open	O
Source	O
Hardware	O
User	O
Group	O
(	O
OSHUG	O
)	O
in	O
the	O
UK	O
has	O
on	O
two	O
occasions	O
run	O
sessions	O
on	O
OpenRISC	B-Device
,	O
while	O
hobbyist	O
Sven-Åke	O
Andersson	O
has	O
written	O
a	O
comprehensive	O
blog	O
on	O
OpenRISC	B-Device
for	O
beginners	O
,	O
which	O
attracted	O
the	O
interest	O
of	O
Electronic	O
Engineering	O
Times	O
(	O
EE	O
Times	O
)	O
.	O
</s>
<s>
Sebastian	O
Macke	O
has	O
implemented	O
jor1k	O
,	O
an	O
OpenRISC	B-Device
1000	O
emulator	O
in	O
JavaScript	B-Language
,	O
running	O
Linux	B-Operating_System
with	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
and	O
Wayland	B-Language
support	O
.	O
</s>
<s>
The	O
OpenRISC	B-Device
community	O
have	O
ported	O
the	O
GNU	B-Application
toolchain	I-Application
to	O
OpenRISC	B-Device
to	O
support	O
development	O
in	O
the	O
programming	O
languages	O
C	B-Language
and	O
C++	B-Language
.	O
</s>
<s>
Using	O
this	O
toolchain	O
the	O
newlib	B-Language
,	O
uClibc	B-Language
,	O
musl	B-Language
(	O
as	O
of	O
release	O
1.1.4	O
)	O
,	O
and	O
glibc	B-Language
libraries	O
have	O
been	O
ported	O
to	O
the	O
processor	O
.	O
</s>
<s>
Dynalith	O
provides	O
OpenIDEA	O
,	O
a	O
graphical	O
integrated	B-Application
development	I-Application
environment	I-Application
(	O
IDE	O
)	O
based	O
on	O
this	O
toolchain	O
.	O
</s>
<s>
A	O
project	O
to	O
port	O
LLVM	B-Application
to	O
the	O
OpenRISC	B-Device
1000	O
architecture	O
began	O
in	O
early	O
2012	O
.	O
</s>
<s>
GCC	B-Application
9	O
released	O
with	O
OpenRISC	B-Device
support	O
.	O
</s>
<s>
The	O
OR1K	B-Device
project	O
provides	O
an	O
instruction	B-Application
set	I-Application
simulator	I-Application
,	O
or1ksim	O
.	O
</s>
<s>
The	O
flagship	O
implementation	O
,	O
the	O
OR1200	B-Device
,	O
is	O
a	O
register-transfer	O
level	O
(	O
RTL	O
)	O
model	O
in	O
Verilog	B-Language
HDL	I-Language
,	O
from	O
which	O
a	O
SystemC-based	O
cycle-accurate	O
model	O
can	O
be	O
built	O
in	O
ORPSoC	O
.	O
</s>
<s>
A	O
high	O
speed	O
model	O
of	O
the	O
OpenRISC	B-Device
1200	I-Device
is	O
also	O
available	O
through	O
the	O
Open	O
Virtual	O
Platforms	O
(	O
OVP	O
)	O
initiative	O
(	O
see	O
OVPsim	B-Application
)	O
,	O
set	O
up	O
by	O
Imperas	O
.	O
</s>
<s>
The	O
mainline	O
Linux	B-Operating_System
kernel	I-Operating_System
gained	O
support	O
for	O
OpenRISC	B-Device
in	O
version	O
3.1	O
.	O
</s>
<s>
The	O
implementation	O
merged	O
in	O
this	O
release	O
is	O
the	O
32-bit	O
OpenRISC	B-Device
1000	O
family	O
(	O
or1k	B-Device
)	O
.	O
</s>
<s>
Formerly	O
OpenRISC	B-Device
1000	O
architecture	O
,	O
it	O
has	O
been	O
superseded	O
by	O
the	O
mainline	O
port	O
.	O
</s>
<s>
Several	O
real-time	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
(	O
RTOS	B-Operating_System
)	O
have	O
been	O
ported	O
to	O
OpenRISC	B-Device
,	O
including	O
NuttX	B-Operating_System
,	O
RTEMS	B-Operating_System
,	O
FreeRTOS	B-Operating_System
,	O
and	O
eCos	B-Operating_System
.	O
</s>
<s>
Since	O
version	O
1.2	O
,	O
QEMU	B-Application
supports	O
emulating	O
OpenRISC	B-Device
platforms	O
.	O
</s>
