From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: [PATCH 8/8] nvdimm docs: add nvdimm Read FIT function Date: Mon, 11 Jul 2016 21:45:18 +0800 Message-ID: <1468244718-3731-9-git-send-email-guangrong.xiao@linux.intel.com> References: <1468244718-3731-1-git-send-email-guangrong.xiao@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: gleb@kernel.org, mtosatti@redhat.com, stefanha@redhat.com, mst@redhat.com, rth@twiddle.net, ehabkost@redhat.com, dan.j.williams@intel.com, kvm@vger.kernel.org, qemu-devel@nongnu.org, Xiao Guangrong To: pbonzini@redhat.com, imammedo@redhat.com Return-path: Received: from mga14.intel.com ([192.55.52.115]:41754 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933752AbcGKN5L (ORCPT ); Mon, 11 Jul 2016 09:57:11 -0400 In-Reply-To: <1468244718-3731-1-git-send-email-guangrong.xiao@linux.intel.com> Sender: kvm-owner@vger.kernel.org List-ID: Add the specification of Read FIT function Signed-off-by: Xiao Guangrong --- docs/specs/acpi_nvdimm.txt | 38 +++++++++++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) diff --git a/docs/specs/acpi_nvdimm.txt b/docs/specs/acpi_nvdimm.txt index 0fdd251..1a31b19 100644 --- a/docs/specs/acpi_nvdimm.txt +++ b/docs/specs/acpi_nvdimm.txt @@ -127,6 +127,38 @@ _DSM process diagram: | result from the page | | | +--------------------------+ +--------------+ =20 - _FIT implementation - ------------------- - TODO (will fill it when nvdimm hotplug is introduced) + QEMU internal use only _DSM function + ------------------------------------ + There is the function introduced by QEMU and only used by QEMU intern= al. + + 1) Read FIT + As we only reserved one page for NVDIMM ACPI it is impossible to map = the + whole FIT data to guest's address space. This function is for NVDIMM = root + device and is used by _FIT method to read a piece of FIT data from QE= MU. + + Input parameters: + Arg0 =E2=80=93 UUID {set to 2f10e7a4-9e91-11e4-89d3-123b93f75cba} + Arg1 =E2=80=93 Revision ID (set to 1) + Arg2 - 0xFFFFFFFF + Arg3 - A package containing a buffer whose layout is as follows: + + +----------+-------------+-------------+-----------------------------= ------+ + | Filed | Byte Length | Byte Offset | Description = | + +----------+-------------+-------------+-----------------------------= ------+ + | offset | 4 | 0 | the offset of FIT buffer = | + +----------+-------------+-------------+-----------------------------= ------+ + + Output: + +----------+-------------+-------------+-----------------------------= ------+ + | Filed | Byte Length | Byte Offset | Description = | + +----------+-------------+-------------+-----------------------------= ------+ + | status | 4 | 0 | return status codes followin= g | + | | | | Chapter 3 in DSM Spec Rev1 = | + +----------+-------------+-------------+-----------------------------= ------+ + | fit data | Varies | 8 | FIT data = | + | | | | = | + +----------+-------------+-------------+-----------------------------= ------+ + + The FIT offset is maintained by the caller itself, current offset plu= gs + the length returned by the function is the next offset we should read= =2E + When all the FIT data has been read out, zero length is returned. --=20 1.8.3.1