Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964841AbbGXTCy (ORCPT ); Fri, 24 Jul 2015 15:02:54 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:58009 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964816AbbGXTCr (ORCPT ); Fri, 24 Jul 2015 15:02:47 -0400 Subject: Re: [PATCH V7 3/5] arm64: mm: add PROT_DEVICE_nGnRnE and PROT_NORMAL_WT To: Catalin Marinas References: <1437515960-16812-1-git-send-email-zjzhang@codeaurora.org> <1437515960-16812-4-git-send-email-zjzhang@codeaurora.org> <20150724161500.GV3550@e104818-lin.cambridge.arm.com> Cc: Will Deacon , "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: <55B28BD4.2050403@codeaurora.org> Date: Fri, 24 Jul 2015 12:02:44 -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: <20150724161500.GV3550@e104818-lin.cambridge.arm.com> 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: 2179 Lines: 48 On 7/24/2015 9:15 AM, Catalin Marinas wrote: > On Tue, Jul 21, 2015 at 10:59:18PM +0100, Jonathan (Zhixiong) Zhang wrote: >> From: "Jonathan (Zhixiong) Zhang" >> >> UEFI spec 2.5 section 2.3.6.1 defines that EFI_MEMORY_[UC|WC|WT|WB] are >> possible EFI memory types for AArch64. Each of those EFI memory types >> is mapped to a corresponding AArch64 memory type. So we need to define >> PROT_DEVICE_nGnRnE and PROT_NORMWL_WT. >> >> MT_NORMAL_WT is defined, and its encoding is added to MAIR_EL1 when >> initializing cpu. >> >> Change-Id: I20ac71ddf74c17e41769ecbb5f8c60eeefbb398a >> Signed-off-by: Jonathan (Zhixiong) Zhang > > I'll let the EFI guys to comment on whether these are needed, what for > (we could probably live just fine only with Device nGnRE and Normal NC). > >> #define PROT_SECT_DEVICE_nGnRE (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE)) >> diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S >> index 838266f5b056..23e265d732f8 100644 >> --- a/arch/arm64/mm/proc.S >> +++ b/arch/arm64/mm/proc.S >> @@ -294,7 +294,7 @@ ENTRY(__cpu_setup) >> msr cpacr_el1, x0 // Enable FP/ASIMD >> msr mdscr_el1, xzr // Reset mdscr_el1 >> /* >> - * Memory region attributes for LPAE: >> + * Memory region attributes for LPAE and EFI: > > LPAE refers to the page table format, the comment probably inherited > from arch/arm. EFI means a completely different thing, so please remove > it. Yes, it was inherited from arch/arm/mm/proc-v7-3level.S. I'll remove the change. That being said, the original statement is not totally accurate I think, so if you prefer, I could change it like following. - * Memory region attributes for LPAE: + * Set MAIR with memory region attributes: -- 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/