Loongson Continues Working On LoongArch For Linux, But It's Mostly Copying MIPS Code

[phoronix]

Phoronix: Loongson Continues Working On LoongArch For Linux, But It's Mostly Copying MIPS Code

Loongson this summer rolled out their 3A5000 processors built on their own "LoongArch" ISA. While the company continues claiming that LoongArch is "not MIPS", the Linux kernel code they continue proposing for the mainline Linux kernel points to it being a close facsimile to MIPS...

https://www.phoronix.com/scan.php?page=news_item&px=LoongArch-MIPS-Copy-Kernel

[qsmcomp]

Flygoat (as jiaxun.yang at flygoat.com) felt tired.
He tried to persuade not to use MIPS heritage.

[Pheckphul]

Of course it's a MIPS ripoff. China's tech industry still hasn't risen to the level of inventing from whole cloth anything that can compete with x86/POWER/ARM. They haven't funneled enough stolen IP back to the fatherland to accomplish that yet. 🤡

[s_j_newbury]

Of course it is MIPS, as I said when MIPS was EOLd. Loongson are in an awkward position, they clearly have no intention of dropping MIPS architecture, and why should they? However, MIPS is dead (officially). They probably *can't* call it MIPS anymore if they want their CPUs to be sold in other markets.

Quite honestly it strikes me as a somewhat political move "killing" the architecture when China is still has a significant strategic stake in the technology. MIPS isn't fashionable anymore, but it is still viable.

Upstream kernel can't really just let a copy-paste new architecture in the kernel, that would be crazy, but Loongson calling it MIPS obviously has legal issues. Maybe some kind of compromise is needed? Maybe rename the kernel MIPS architecture: "(not) MIPS"?! ;-)

[mlau]

Flygoat (as jiaxun.yang at flygoat.com) felt tired.
He tried to persuade not to use MIPS heritage.

a new microarch requires a toolchain, and that is a significant undertaking. MIPS itself was/is in need of a substantial investment in compiler/libraries/... but it's usable.
I do understand the decision.

[torsionbar28]

MIPS hasn't been competitive in a long time. Who cares about Loongson though, it's effectively a China-domestic product, and it's slow and buggy. Not sure why Linux should bother mainlining anything like this, has no practical value to anyone outside of China. It is all a political move from the CCP, part of their "Made in China 2025" initiative, to move towards a China-domestic supply chain. "China First".

[ddriver]

a new microarch requires a toolchain, and that is a significant undertaking. MIPS itself was/is in need of a substantial investment in compiler/libraries/... but it's usable.
I do understand the decision.

Hello, it is 2021 calling...

Today it is fairly easy to roll out a toolchain. Heck, it is getting "pedestrian" level to design semiconductors, with modern design tools, you can simply import and interconnect IP blocks and have that manufactured if you can afford to.

Today it would be stupid to resort to anything legacy, much less bother to reverse-engineer a complex design, not for the sake of manufacturing and selling products anyway. It is so much cleaner and easier to start from scratch.

[mlau]

There's a difference between gluing IP-blocks together and designing a complete instruction set from scratch.

[bug77]

Reminds me of Huawei swearing their mobile OS is "entirely new", without even bothering to remove Android references from the source code.

[ddriver]

There's a difference between gluing IP-blocks together and designing a complete instruction set from scratch.

Really? You find it hard to figure out a set of instructions that may be required for a computer to run?