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Mon, 1 Feb 2021 16:56:04 -0500 Received: from mail-ej1-x62a.google.com (mail-ej1-x62a.google.com [IPv6:2a00:1450:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 896F3C06174A for ; Mon, 1 Feb 2021 13:55:24 -0800 (PST) Received: by mail-ej1-x62a.google.com with SMTP id rv9so26717500ejb.13 for ; Mon, 01 Feb 2021 13:55:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=RZDofSxjQfRvCD9og+/lS0h09No2LY/OIRXR8uXND+Y=; b=n/z8H83/8L7uutAMt7vBH/0PM6mOT4y6pk0N26xWUl6K+PVgCDp+YXxmyzAL/MNeYh FhyEJ+t3PDTgPqvNYAwrmu/2KJ3RSWWl25QxaeD/NM47uE2zcoMu8RcyoSL8izErXY6l E3EJtJY7XxeoodByW/FBN5conQMjdj+7X+ZWMb1sp1jVzYgjowklKOspBFlhffuWjaUF k1lqgo0WuzZ8ko2jjsDPMOV1KCcBrq7Nvugt5PiU7GKEa+IweAe0Eyy2Ee1Y28XzLmQf LczqNPRsAkEeW5JyJaL57yMfWD/dMourQswAGFX+THDobxnkQn4fgT0unLYSJSgoQfCN Owbg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; 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charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 1, 2021 at 1:53 PM David Rientjes wrote: > > On Mon, 1 Feb 2021, Ben Widawsky wrote: > > > > > diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl > > > > new file mode 100644 > > > > index 000000000000..fe7b87eba988 > > > > --- /dev/null > > > > +++ b/Documentation/ABI/testing/sysfs-bus-cxl > > > > @@ -0,0 +1,26 @@ > > > > +What: /sys/bus/cxl/devices/memX/firmware_version > > > > +Date: December, 2020 > > > > +KernelVersion: v5.12 > > > > +Contact: linux-cxl@vger.kernel.org > > > > +Description: > > > > + (RO) "FW Revision" string as reported by the Identify > > > > + Memory Device Output Payload in the CXL-2.0 > > > > + specification. > > > > + > > > > +What: /sys/bus/cxl/devices/memX/ram/size > > > > +Date: December, 2020 > > > > +KernelVersion: v5.12 > > > > +Contact: linux-cxl@vger.kernel.org > > > > +Description: > > > > + (RO) "Volatile Only Capacity" as reported by the > > > > + Identify Memory Device Output Payload in the CXL-2.0 > > > > + specification. > > > > + > > > > +What: /sys/bus/cxl/devices/memX/pmem/size > > > > +Date: December, 2020 > > > > +KernelVersion: v5.12 > > > > +Contact: linux-cxl@vger.kernel.org > > > > +Description: > > > > + (RO) "Persistent Only Capacity" as reported by the > > > > + Identify Memory Device Output Payload in the CXL-2.0 > > > > + specification. > > > > > > Aren't volatile and persistent capacities expressed in multiples of 256MB? > > > > As of the spec today, volatile and persistent capacities are required to be > > in multiples of 256MB, however, future specs may not have such a requirement and > > I think keeping sysfs ABI easily forward portable makes sense. > > > > Makes sense, can we add that these are expressed in bytes or is that > already implied? Makes sense to declare units here.