Loongson

Loongson 2E

Loongson 2E was designed by ICT (Institute of Computing Technology), a department of The Chinese Academy of Sciences, helped and manufactured by STMicroelectronics.

ST Generic Part Number: STLS2E02

Features

Microarchitecture:

- 64 bit

- 9 pipeline stages

- 4-issue Out-Of-Order Executive

- 2 ALU, 2 FALU, 1 SIMD, 1 Load/Store Units

ISA: MIPSIII

Cache: 64KB L1 date, 64KB L1 instruction, on-chip 512KB L2.

Clock Frequence: 600MHz - 800MHz.

TDP: 4 Watt at 700MHz

Integrated: DDR-333 memory controller.

Highlights

ST's Leading Edge 90nm process.

Some new instructions: Allow write to register directly without MFLO or MFHI.

Some new instructions: MADD.[S|D] MSUB.[S|D] NMADD.[S|D] NMSUB.[S|D].

Some new SIMD instructions: simmilar to MMX, using FPU for parallel fix-point arithmetic.

An Executive bit: help OS to protect from buffer-flow attack.

The following 2F is under manufacture(July,2007) which has a higher frequence, an on-chip DDR2 controller and advanced power control technology.

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• http://www.st.com/stonline/products/literature/bd/13367.htm
• http://www.loongson.cn/
• http://en.wikipedia.org/w/index.php?title=Godson
• My CPU is Loongson(Godson)!!! blog
• http://www.cyrius.com/journal/2007/03/08
• http://linuxdevices.com/news/NS5724036154.html

Devices based on this CPU

• Fulong

Processor documentation

Chinese version

• http://www.lemote.com/Files/DownLoad/1164864817.pdf

English version

• http://www.lemote.com/upfiles/godson2e-user-manual-V0.6.pdf

Loongson 2F

Loongson 2F is the latest processor in Loongson 2 Family. No improvements from 2E except following points: -Higher Clock Frequence: 1.2GHz maximum -Advanced power control technology: less than 6 Watt under 1GHz in the same 90nm -Intergrated DDR2 controller -Intergrated northbridge：Faster IO with PCI－X 66 bus(compared with former PCI bus) -Smaller Packaging.