lkml.org 
[lkml]   [2015]   [Mar]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 3/3] e820: Add the unknown-12 Memory type (DDR3-NvDIMM)
    On 03/05/2015 10:56 PM, Dan Williams wrote:
    > On Thu, Mar 5, 2015 at 2:24 AM, Boaz Harrosh <boaz@plexistor.com> wrote:
    >>
    <>
    >> Now the ACPI comity, as far as I know, did not yet define a
    >> standard type for NvDIMM. Also, as far as I know any NvDIMM
    >> standard will only be defined for DDR4. So DDR3 NvDIMM is
    >> probably stuck with this none STD type.
    >
    > There's no relation between E820 types and DDR technology revisions.
    >

    Yes and no, I mean the DDR4 has extra legs and signals defined
    for NvDIMM. So DDR3 will always mean different style of NvDIMM.

    You tell me. Say the standard finally comes out. Will I have a
    new bios from Intel for my DDR3 system here in the lab that will
    report the new STD type ?

    What I meant is that DDR3 is too old for the proposed STD and probably
    only DDR4 NvDIMMs will be supported in systems. The way the STD defined
    it.

    <>
    >> In this patch I name type-12 "unknown-12". This is because of
    >> ACPI politics that refuse to reserve type-12 as DDR3-NvDIMM
    >
    > It's not "politics". Setting standards takes time and the platforms
    > in question simply jumped the gun to enable a proof-of-concept.
    >

    So ye, but once you have 100,000 devices out there, then the dichotomy
    between standards-takes-time vs proof-of-concept, becomes politics.

    This is the definition of politics, when life moves faster than some
    "body", the "body" stands on its back feet and shoots fire from
    his head.

    >> and members keep saying:
    >> "What if ACPI assigns type-12 for something else in future"
    >>
    >> [And I say: Then just don't. Please?]
    >
    > Once a standard number is assigned, platform firmwares can update
    > type-12 to that number. We might consider a compile time override for
    > these niche/pre-standard systems that can't/won't update, but it's not
    > clear to me that we even need to go that far.
    >

    OK, so I do not understand what you want. Yes or No to this patch?

    This patch with unknown-12 is for NOW. For systems already running.

    So we can differentiate between reserved-unknown which might mean
    type-13 and this here bastard type-12 which we know is NvDIMM but
    for future sake we do not call by name?

    Or maybe we should call it NVDIMM-12 ?

    Thanks
    Boaz



    \
     
     \ /
      Last update: 2015-03-09 12:41    [W:4.001 / U:0.240 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site