Re: [PATCH v2] powerpc: Add cpu family documentation
From: Arnd Bergmann <arnd@arndb.de>
Date: 2014-04-30 18:33:49
On Wednesday 30 April 2014 16:45:08 Michael Ellerman wrote:
quoted
quoted
+ v v + +--------------+ +-------+ +----------------+ + | POWER4+ | ---------------> | 970 | | 7447 | + +--------------+ +-------+ +----------------+ + | | | + | | | + v v v + +--------------+ +-------+ +-------+ +----------------+ + | POWER5 | --> | Cell | | 970FX | | 7448 | + +--------------+ +-------+ +-------+ +----------------+ + | | + | | + v v + +--------------+ +-------+ + | POWER5+ | | 970MP | + +--------------+ +-------+ + | + | + v + +--------------+ + | POWER5++ | + +--------------+ + | + | + v + +--------------+ + | POWER6 | + +--------------+ + | + | + v
I think Cell and POWER6 are somewhat misrepresented here. Cell (together with Xenon, which is the same core) is basically an independent development unrelated to POWER5. POWER6 shares a lot of concepts with Cell, and IIRC is much closer related to Cell than to POWER5, though I don't remember which one was designed first. Probably code went both ways, and POWER6 got some enhancements that didn't make it into the Cell PPU. They both contain VMX (Altivec) and have an in-order pipeline. POWER6 is also closely related to z10, while POWER7 then includes aspects of both POWER5 and POWER6 but no longer shares much with z196, which in turn is derived from z10. Arnd