Loongson () is the name of a family of general-purpose, MIPS architecture-compatible, later in-house LoongArch architecture microprocessors, as well as the name of the Chinese fabless company (Loongson Technology) that develops them. The processors are alternately called Godson processors,
History
The Godson processors, based on MIPS architecture, were initially developed at the Institute of Computing Technology (ICT), Chinese Academy of Sciences (CAS). The chief architect was . The development of the first Loongson chip was started in 2001. The aim of the Godson project was to develop "high performance general-purpose microprocessors in China",
In 2021, Loongson filed for an initial public offering on the Shanghai Stock Exchange STAR Market. The company was seeking to raise US$500 million.
In April 2024 Loongson processors got a large boost when a school district in the city of Hebi commenced a trial of 10,000 PCs powered by computers featuring the Loongson 3A5000 processor and the Deepin-based Unity Operating System. According to The Register, this trial project is to be used to promote the use of Loongson-and-Linux computers within the Chinese school system, which could potentially result in 50 million Loongson-based computers being sold to Chinese schools every year until 2030.
Instruction set architectures
MIPS
Loongson began by using the MIPS64 instruction set architecture (ISA). The internal microarchitecture was independently developed by ICT. Early implementations of the family lacked four instructions patented by MIPS Technologies (US4814976A, unaligned load-store) to avoid legal issues.
In 2007, a deal was reached by MIPS Technologies and ICT. STMicroelectronics bought a MIPS license for Loongson, and thus the processor can be promoted as MIPS-based or MIPS-compatible instead of MIPS-like.
In June 2009, ICT licensed the MIPS32 and MIPS64 architectures directly from MIPS Technologies.
In January 2024, Loongson won a case over rights to use MIPS architecture.
LoongISA
The Loongson 3A2000 in 2015 saw the adoption of 1.0, an expanded instruction set that is a superset of MIPS64 release 2.
The ISA has been referred to as "a fork of MIPS64r6" due to a perceived lack of changes judging from instruction listings. The Register reported in November 2021 that LoongArch might combine the best parts of MIPS and RISC-V, along with custom instructions.
- GS464 series: MIPS64 core with four-way superscalar out-of-order issue.
- LA664 is the architecture for the 3A6000/3C6000 series processors.
It has been noted by the community that the naming of the Loongson microarchitectures is not consistent, with different products being noted to have the same processor core, even though the instructions sets might not be exactly compatible.
- Godson-3, multi-core processors for higher performance computers, high-performance computing and servers
- Loongson 3, LoongArch processors
Godson-1
The first Loongson processor, the Godson-1, was designed in 2001, released in 2002, and is a 32-bit CPU running at a clock speed of 266 MHz. Godson-1 series chips either use the GS132 or GS232 cores. In May 2013 development of the 3C was suspended, in favour of developing the 3A2000 processor. The processor series was Loongson's first with their own developed instruction set architecture (ISA), called "LoongArch".
6000 series
thumb|Loongson 3A6000 CPU
In 2022 Loongson announced their 6000 series processors. The company said that the updated processor architecture would use new "LA664" cores The processor is fabricated using a 14 nm or 12 nm process and supports the fairly old DDR4 standard for memory. The Register reported that Loongson had demonstrated benchmarks suggesting that the 3A6000 processor was competitive with an Intel 10th-generation Core processor (launched in 2019). The CPU is a monolithic chip with 16 cores; it features the LA664 proprietary MIPS-derived microarchitecture supporting simultaneous multithreading technology (SMT). The 7 nm chips, which could go on sale in 2025, will probably be produced entirely in China, due to US sanctions. Loongson was said to have stated that the company had already started the IP design work and that the finished product would include modern technology, e.g. DDR5 and PCIe 5.0. Any operating system supporting the MIPS architecture should theoretically work. Windows CE was ported to a Godson-based system with minimal effort. In 2010, Lemote ported an Android distribution to the Godson platform.
Godson machines are used in the package-building and CI infrastructure of Debian and Golang, respectively. This is partially because of Loongson's status as the only vendor producing application-grade MIPS CPUs for retail.
Compiler support
The GNU Compiler Collection (GCC) is the main compiler for software development on the Loongson platform.
Before 2021 LLVM support was still inadequate due to missing workarounds for Loongson's CPU errata on MIPS.
LoongArch
Operating systems
As LoongArch is not compatible with MIPS, operating systems have to be ported to work on LoongArch.
Chinese Linux distributions supporting LoongArch include Kylin, Loongnix, Deepin, Unity Operating System, AOSC OS, and Loong Arch Linux. There are efforts to build LoongArch support into community versions of Linux.
Other common Linux distributions supporting LoongArch include Alpine Linux (since 3.21.0), Debian, Gentoo Linux, Nixpkgs (since 25.11), OpenWrt (since 24.10), and Slackware.
Compiler support
LoongArch is supported by the GCC, LLVM, Golang compilers. OpenJDK and .NET ports exist but are not accepted by upstream developers due to U.S. sanctions against Loongson.
Loongson microprocessor specifications
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<div style="overflow-x:scroll">
{| class="wikitable sortable" summary="This table contains specifications for certain Godson processors"
|-
! rowspan="3" |Series
! rowspan="3" |Model
! rowspan="3" abbr="Frequency" |Frequency<br>(MHz)
! rowspan="3" abbr="Architecture" |Architecture
! rowspan="3" |Microarchitecture
! rowspan="3" |Year
! rowspan="3" abbr="Cores" |Cores
! rowspan="3" abbr="Process" |Process<br>(nm)
! rowspan="3" abbr="Transistors" |Transistors<br>(million)
! rowspan="3" abbr="Size" |Die size<br>(mm<sup>2</sup>)
! rowspan="3" abbr="Power" |Power<br>(W)
! rowspan="3" abbr="Voltage" |Voltage<br>(V)
! colspan="4" abbr="Data cache" |Cache (KiB)
! rowspan="3" |Peak floating point performance<br>(GFLOPS)
! rowspan="3" abbr="Perf" |Performance<br>int/fp [SPEC2000] (SPEC2006)
! rowspan="3" |Remarks
|-
! colspan="2" |L1(single core)
! rowspan="2" |L2
! rowspan="2" |L3
|-
! Data
! instruction
|-
! rowspan="5" |Godson
| 1
| 266
| MIPS-II 32-bit
|
| 2001
| 1
| 180
| 22
| 71.4
| 1.0
|
| 8
| 8
|
|
| 0.6
|[19/25]
|
|-
| FCR_SOC
| 266
| MIPS-II 32-bit
|
| 2007
| 1
| 180
|
|
|
|
| 8
| 8
|
|
| 0.6
|
|
|-
| 2B
| 250
| MIPS-III 64-bit
|
| 2003
| 1
| 180
|
|
|
|
| 32
| 32
|
|
|
| [52/58]
|
|-
| 2C
| 450
| MIPS-III 64-bit
|
| 2004
| 1
| 180
| 13.5
| 41.5
|
|
| 64
| 64
|
|
|
| [159/114]
|
|-
| 2E
| 1000
| MIPS-III 64-bit
| GS464 (r1) (prototype)
| 2006
| 1
| 90
| 47
| 36
| 7
| 1.2
| 64
| 64
| 512
|
|
|[503/503]
|
|-
! rowspan="5" |Loongson 1
| 1A
| 300
| MIPS32
| GS232
| 2010
| 1
| 130
| 22
| 71.4
| 1.0
|
| 16
| 16
|
|
| 0.6
|
|
|-
| 2GP
| rowspan="2" | 800
| rowspan="2" | MIPS64
| rowspan="2" | GS464 (r2)
| rowspan="2" | 2013
| rowspan="2" | 1
| rowspan="2" | 65
| rowspan="2" | 82
| rowspan="2" | 65.7
| rowspan="2" | 8
| rowspan="2" | 1.15
| rowspan="2" | 64
| rowspan="2" | 64
| rowspan="2" | 1024
| rowspan="2"
| rowspan="2" | 3.2
| rowspan="2"
| rowspan="2" |
|-
|2I
|-
| 2H
| 1000
| MIPS64
| GS464 (r2)
| 2012
| 1
| 65
| 152
| 117
| 5
| 1.15
| 64
| 64
| 512
|
| 4
|
|
|-
| 2K1000
| 1000
| MIPS64 Release 2 LoongISA 1.0
| GS264E
| 2017
| 2
| 40
| 1900
| 79
| 5
| 1.1
| 32
| 32
| 256 × 2
| 1024
| 8
|
|
|-
| 3B1500
| 1200–1500
| MIPS64 Release 2 LoongISA 1.0
| GS464V
| 2012
| 4+4
| 32
| 1140
| 142.5
| 30(typical)<br>60(vector)
| 1.15–1.35
| 64
| 64
| 128 × 8
| 8192
| 150
|
|
|-
| 3A1500-I
| rowspan="3" |800–1000
| rowspan="3" |MIPS64 Release 2 LoongISA 1.0
| rowspan="3" |GS464E
| rowspan="3" |2015
| rowspan="3" |4
| rowspan="3" |40
| rowspan="3" |621
| rowspan="3" |202.3
| rowspan="3" |15
| rowspan="3" |1.15–1.25
| rowspan="3" |64
| rowspan="3" |64
| rowspan="3" |256 × 4
| rowspan="3" |4096
| rowspan="3" |16
| rowspan="3" |(6/??)
| rowspan="3" |
|-
|3C6000
|1800-2300
|LoongArch
|LA664
|2024
|16
|12
|
|
|
|
|
|
|
|32768
|
|
|
|-
|3D6000
|1600-2100
|LoongArch
|LA664
|2024
|32
|12
|
|
|
|
|
|
|
|65536
|
|
|
|-
|3A7000
|
|LoongArch
|LA864
|2025
|8
|7
|
|
|
|
|
|
|
|16384
|
|
|
|-
|3B7000
|3500
|LoongArch
|LA864
|2025
|16
|7
|
|
|
|
|
|
|
|32768
|
|
| a small-form-factor computer based on the 400 MHz Loongson 2.
the new 8.9" netbook from the Chinese manufacturer Lemote that replaced mengloong, Yeeloong (Portable Dragon), running Debian, is available in Europe from the Dutch company Tekmote Electronics.
In January 2010, Jiangsu province planned to buy 1.5 million Loongson PCs.
In September 2011, Lemote announced the Yeeloong-8133 13.3" laptop featuring 900 MHz, quad-core Loongson-3A/2GQ CPU.
Supercomputers
On 26 December 2007, China revealed its first Loongson-based supercomputer in Hefei. The KD-50-I has a reported peak performance of 1 TFLOPS, and about 350 GFLOPS measured by LINPACK. This supercomputer was designed by a joint team led by Chen Guoliang at the computer science technology department of the University of Science and Technology of China (USTC) and ICT (the secondary contractor). KD-50-I is the first Chinese built supercomputer to utilize domestic Chinese CPUs, with a total of more than 336 Loongson-2F CPUs, and nodes interconnected by ethernet. The size of the computer was roughly equivalent to a household refrigerator and the cost was less than RMB800,000 (approximately 120,000, 80,000).
In 2012 it was reported that Loongson processors were to be found in the Sunway BlueLight MPP and Dawning 6000 supercomputers.