From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751345AbdAPPPd (ORCPT ); Mon, 16 Jan 2017 10:15:33 -0500 Received: from mail-oi0-f52.google.com ([209.85.218.52]:34765 "EHLO mail-oi0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750939AbdAPPPa (ORCPT ); Mon, 16 Jan 2017 10:15:30 -0500 MIME-Version: 1.0 In-Reply-To: <20170112213354.GC2709@dhcp-128-65.nay.redhat.com> References: <20170112094118.815108042@redhat.com> <20170112094214.909117564@redhat.com> <20170112213354.GC2709@dhcp-128-65.nay.redhat.com> From: Bhupesh Sharma Date: Mon, 16 Jan 2017 20:45:29 +0530 Message-ID: Subject: Re: [PATCH 2/4] efi/x86: move efi bgrt init code to early init code To: Dave Young Cc: Ard Biesheuvel , Matt Fleming , "linux-efi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , Nicolai Stange , Ingo Molnar , Thomas Gleixner , "hpa@zytor.com" , Dan Williams , =?UTF-8?Q?Mika_Penttil=C3=A4?= Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thanks Dave. On Fri, Jan 13, 2017 at 3:03 AM, Dave Young wrote: > On 01/12/17 at 04:20pm, Ard Biesheuvel wrote: >> On 12 January 2017 at 09:41, Dave Young wrote: >> > Before invoking the arch specific handler, efi_mem_reserve() reserves >> > the given memory region through memblock. >> > >> > efi_bgrt_init will call efi_mem_reserve after mm_init(), at that time >> > memblock is dead and it should not be used any more. >> > >> > efi bgrt code depend on acpi intialization to get the bgrt acpi table, >> > moving bgrt parsing to acpi early boot code can make sure efi_mem_reserve >> > in efi bgrt code still use memblock safely. >> > >> > Signed-off-by: Dave Young >> >> I know this is probably out of scope for you, but since we're moving >> things around, any chance we could do so in a manner that will enable >> BGRT support for arm64/ACPI? Happy to test/collaborate on this. >> > > I'm happy to do so, Bhupesh Sharma said he had > some investigation on that already, I would like to ask him to help on that. > > Already cced him.. Hi Ard, I have started working on an implementation where most of the BGRT code which exists inside 'arch/x86/platform/efi-bgrt.c' can be reused for ARM/ARM64. I am testing a RFC approach for the same using Qemu for AARCH64. I have sent out a patch to enable BGRT support in ArmVirtPkg (see [1]) I have one question regarding the placement of the early bgrt handling code so that it can be reused on both arm/arm64 and x86: - Should I consider moving the current code from arch/x86/platform/efi-bgrt.c to outside arch/x86 so that it can be used by both the ARCHs or should I reuse the existing x86 stuff in a ARM specific way - no mem_remap for e.g. in a find inside arch/arm - say efi-arm-bgrt.c Suggestions? [1] https://lists.01.org/pipermail/edk2-devel/2017-January/006588.html Regards, Bhupesh