Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754485AbbGTSWN (ORCPT ); Mon, 20 Jul 2015 14:22:13 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:52467 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752940AbbGTSWK (ORCPT ); Mon, 20 Jul 2015 14:22:10 -0400 Subject: Re: [PATCH V5 3/4] arm64: apei: implement arch_apei_get_mem_attributes() To: Hanjun Guo , Will Deacon References: <1436920316-18127-1-git-send-email-zjzhang@codeaurora.org> <1436920316-18127-4-git-send-email-zjzhang@codeaurora.org> <20150716171853.GO26390@arm.com> <55A85C3C.9050906@codeaurora.org> <55A8D3A1.10709@linaro.org> Cc: Catalin Marinas , "fu.wei@linaro.org" , "al.stone@linaro.org" , "bp @ alien8 . de Matt Fleming" , "rjw@rjwysocki.net" , "linux-kernel@vger.kernel.org" , "linaro-acpi@lists.linaro.org" From: "Zhang, Jonathan Zhixiong" Message-ID: <55AD3C4F.7070400@codeaurora.org> Date: Mon, 20 Jul 2015 11:22:07 -0700 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <55A8D3A1.10709@linaro.org> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4167 Lines: 103 Thanks for the feedback, Hanjun. On 7/17/2015 3:06 AM, Hanjun Guo wrote: > On 07/17/2015 09:37 AM, Zhang, Jonathan Zhixiong wrote: >> Thank you Will for the feedback. Pls. see comments below. >> >> On 7/16/2015 10:18 AM, Will Deacon wrote: >>> On Wed, Jul 15, 2015 at 01:31:55AM +0100, Jonathan (Zhixiong) Zhang >>> wrote: >>>> From: "Jonathan (Zhixiong) Zhang" >>>> >>>> If the physical address has memory attributes defined by EFI >>>> memmap as EFI_MEMORY_UC, the page protection type is >>>> PROT_DEVICE_nGnRE. Otherwise, the page protection type is >>>> PAGE_KERNEL. >>>> >>>> Signed-off-by: Jonathan (Zhixiong) Zhang >>>> --- >>>> arch/arm64/kernel/Makefile | 1 + >>>> arch/arm64/kernel/apei.c | 27 +++++++++++++++++++++++++++ >>>> 2 files changed, 28 insertions(+) >>>> create mode 100644 arch/arm64/kernel/apei.c >>>> >>>> diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile >>>> index 426d0763c81b..c135f1e4e3b8 100644 >>>> --- a/arch/arm64/kernel/Makefile >>>> +++ b/arch/arm64/kernel/Makefile >>>> @@ -36,6 +36,7 @@ arm64-obj-$(CONFIG_EFI) += efi.o >>>> efi-stub.o efi-entry.o >>>> arm64-obj-$(CONFIG_PCI) += pci.o >>>> arm64-obj-$(CONFIG_ARMV8_DEPRECATED) += armv8_deprecated.o >>>> arm64-obj-$(CONFIG_ACPI) += acpi.o >>>> +arm64-obj-$(CONFIG_ACPI_APEI) += apei.o >>>> >>>> obj-y += $(arm64-obj-y) vdso/ >>>> obj-m += $(arm64-obj-m) >>>> diff --git a/arch/arm64/kernel/apei.c b/arch/arm64/kernel/apei.c >>>> new file mode 100644 >>>> index 000000000000..9c6b62f40ad7 >>>> --- /dev/null >>>> +++ b/arch/arm64/kernel/apei.c >>>> @@ -0,0 +1,27 @@ >>>> +/* >>>> + * Arch-specific APEI-related functions. >>>> + * >>>> + * This program is free software; you can redistribute it and/or >>>> modify >>>> + * it under the terms of the GNU General Public License as >>>> published by >>>> + * the Free Software Foundation; either version 2 of the License, or >>>> + * (at your option) any later version. >>>> + * >>>> + * This program is distributed in the hope that it will be useful, >>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >>>> + * GNU General Public License for more details. >>>> + */ >>>> + >>>> +#include >>>> + >>>> +#include >>>> + >>>> +#include >>>> + >>>> +pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr) >>>> +{ >>>> + if (efi_mem_attributes(addr) & EFI_MEMORY_UC) >>>> + return PROT_DEVICE_nGnRE; >>>> + else >>>> + return PAGE_KERNEL; >>>> +} >>> >>> Do we really need a new file and out-of-line call for this? >> We have a choice of either adding this function to >> arch/arm64/kernel/acpi.c, or creating >> arch/arm64/kernel/apei.c. As we continue to work on firmware first >> HW error handling for arm64, more arm64 specific APEI related functions >> may need to be implemented, thus I think it would be good to create >> arch/arm64/kernel/apei.c. That being said, to date we have found >> the needs to have only two arm64 specific APEI related functions. >> The other one can be found in LEG kernel, through this commit: >> aa2d69c88b27 ACPI, APEI, ARM64: APEI initial support for aarch64 >> My understanding is that Linaro will work on to upstream that commit. I >> do not strongly prefer either choice. > > For me, I would like to locate those codes in arm64/kernel/acpi.c and > guard with CONFIG_ACPI_APEI now, if we want to extend in the future, > then let's see if we do anything for that, in this way, we can make ACPI > on ARM64 (the arch code) self-contained. Makes sense. Will do. > > Thanks > Hanjun -- Jonathan (Zhixiong) Zhang The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/