• Yokemate of Keyboards
    Yokemate of Keyboards
    Andreas_Wolf
    Posts: 11095 from 2003/5/22
    From: Germany
    Update:

    > Significant quote from Power ISA 3.0 spec:
    > "In 2006, Freescale and IBM collaborated on the creation of the Power ISA Version
    > 2.03, which represented the reunification of the architecture by combining Book E
    > content with the more general purpose PowerPC Version 2.02. Power ISA Version
    > 3.0 continues this integration by providing a single Book III for all Power
    > implementations, and also by eliminating optional architecture categories to
    > ensure increased application portability between Power processors."
    >
    > Updated quote from Power ISA 3.0b spec:
    > "In 2006, Freescale and IBM collaborated on the creation of the Power ISA Version
    > 2.03, which represented the reunification of the architecture by combining Book E
    > content with the more general purpose PowerPC Version 2.02. The resulting
    > Architecture included environment-specific privileged architecture optimizations
    > (two Book IIIs) and optional application-specific facilities (categories) as
    > extensions to a pervasive base architecture. Power ISA Version 3.0 B focuses this
    > integration by choosing a single Book III and a set of widely used categories to
    > become part of the base architecture for all forward-looking Power
    > implementations. All other optional architecture categories have been eliminated
    > to ensure increased application portability between Power processors. Legacy
    > embedded applications that require the eliminated material will continue
    > to use V. 2.07B."
    >
    > Funny thing to say that Power ISA 3.0 "continues" or "focuses" the integration of
    > PowerPC ISA and Book E ISA, when in fact it essentially *reverts* this integration
    > by eliminating the parts that Book E ISA had brought into it.

    Slightly updated quote from brand-new Power ISA 3.1 (POWER10) spec:
    "In 2006, Freescale and IBM collaborated on the creation of the Power ISA Version 2.03, which represented the reunification of the architecture by combining Book E content with the more general purpose PowerPC Version 2.02. The resulting architecture included environment-specific privileged architecture optimizations (two Book IIIs) and optional application-specific facilities (categories) as extensions to a pervasive base architecture. In support of the OpenPOWER Foundation’s standardization of server architecture, Power ISA Version 3.0 streamlined this integration by choosing a single Book III and a set of widely used categories to become part of the base architecture for all forward-looking Power implementations. All other optional architecture categories were eliminated to ensure increased application portability between Power processors. Legacy embedded applications that require the eliminated material will continue to use V. 2.07B."

    I'm not sure that changing the wording from "focuses" to "streamlined" eliminates the misrepresentation of the facts.

    Also interesting from the 3.1 spec:
    "Power ISA Version 3.0C took the first step in reintroducing optionality into the architecture as the Power ISA moves to an “open” model governed by the OpenPOWER Foundation. Material later in the preface identifies compliancy subsets of the architecture and the optional features which they comprise. [...] Change bars have been included in the body of this document to indicate changes from the Power ISA Version 3.0C. [...] Version 3.1 of the Power ISA [...] is intended to supersede and replace version 3.0C. [...] This version was created by making miscellaneous corrections and by applying the following requests for change (RFCs) to Power ISA Version 3.0C. Change bars in this summary of changes indicate changes relative to v3.0C."

    Power ISA "3.0C"? Never heard of that. Does anybody have a link to that "3.0C" spec?
  • »11.05.20 - 20:19
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