From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751502AbbCJFMP (ORCPT ); Tue, 10 Mar 2015 01:12:15 -0400 Received: from smtp.nue.novell.com ([195.135.221.5]:59720 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750967AbbCJFMO (ORCPT ); Tue, 10 Mar 2015 01:12:14 -0400 Date: Tue, 10 Mar 2015 13:11:37 +0800 From: joeyli To: Boaz Harrosh Cc: Andy Lutomirski , Dan Williams , Ingo Molnar , X86 ML , linux-kernel , "Roger C. Pao" , Thomas Gleixner , linux-nvdimm , "H. Peter Anvin" , Matthew Wilcox , Christoph Hellwig , Ross Zwisler Subject: Re: [PATCH 3/3] e820: Add the unknown-12 Memory type (DDR3-NvDIMM) Message-ID: <20150310051137.GA18810@linux-rxt1.site> References: <54F82CE0.4040502@plexistor.com> <54F82ED1.8030900@plexistor.com> <54FD8DBD.3070309@plexistor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <54FD8DBD.3070309@plexistor.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Mon, Mar 09, 2015 at 02:10:37PM +0200, Boaz Harrosh wrote: > On 03/06/2015 01:09 AM, Andy Lutomirski wrote: > <> > > > > I will be shocked if a standard of this form ever appears. Modern > > systems *don't have e820*. The BIOSes that are using this type 12 > > hack are awful throwbacks. > > So far the systems we have, with DDR4 NvDIMM(s) (Actual chips arriving soon) > still have BIOS (On by default). The BIOS was yelled "Wolfe" for so long NOW ;-) > Again these are working system in the field, who will switch them all to UEFI? > > How will the UEFI present them to the system? can you point me to the relevant > code? (Or did you mean BIOS but with a different communication path than e820?) > Per my understand... With EFI Boot Stub, there have setup_e820() codes in arch/x86/boot/compressed/eboot.c that used to transfer EFI memmap to e820 entries. Currently doesn't have any EFI_MEMORY_TYPE reflects to NvDIMM that will map to e820_type. I wonder what kind of EFI_MEMORY_TYPE reported by UEFI BIOS on those "shipped NvDIMMs motherboards", like supermicro X9DRH-iF-NV. Then we may need add code to setup_e820() for mapping the efi memory type to e820 type 12 region. > > > > --Andy > > > > Thanks > Boaz > Thanks a lot! Joey Lee