[libre-riscv-dev] PowerISA 3.1 (Power10) spec released

Luke Kenneth Casson Leighton lkcl at lkcl.net
Mon May 11 19:37:03 BST 2020

crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68

On Mon, May 11, 2020 at 7:31 PM Yehowshua <yimmanuel3 at gatech.edu> wrote:
> > On May 11, 2020, at 2:25 PM, Luke Kenneth Casson Leighton <lkcl at lkcl.net> wrote:
> >
> >> IBM has released the POWER10 ISA doc.
> OK - before we get confused on all this power non-sense any further - I’d like to stress that the ISA is currently committed at POWER3.0B.

yehyeh.  right now, to stand a chance to hit oct 2020, we've cut FP,
cut vector, cut regfile stratification - everything.  absolute basic

> POWER10 is an IBM processor family set to hit market 2021.
> Why on earth IBM thought it was a good Idea to name a spec and implementation with conflicting numbers? Only God knows.


we do however need to have the conversation with them, to plan ahead.

page xii (OpenPOWER Architecture Sandbox), i see where they're going...
"Developers are encour-aged to provide a means to disable custom extensions
to present an architecture that is supported by standard
system software and toolchain"

um... that's precisely what ISANS / ISAMUX is for!!

*smacks forehead*.

the language is nowhere near strong or clear enough.  "encouraged" is
inadequate.  it needs to be, "if you go one route, you follow these
procedures.  if you go the other route you follow _these_ procedures"

Alain, Yehowshua: we need to talk with Hugh about this.


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