Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752216AbbHMIWd (ORCPT ); Thu, 13 Aug 2015 04:22:33 -0400 Received: from mail-wi0-f179.google.com ([209.85.212.179]:35615 "EHLO mail-wi0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751993AbbHMIWM (ORCPT ); Thu, 13 Aug 2015 04:22:12 -0400 Date: Thu, 13 Aug 2015 10:22:07 +0200 From: Ingo Molnar To: Matt Fleming Cc: Thomas Gleixner , "H. Peter Anvin" , "Jonathan (Zhixiong) Zhang" , linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, Matt Fleming , Ard Biesheuvel , Catalin Marinas , Hanjun Guo Subject: Re: [PATCH 1/2] arm64: apei: implement arch_apei_get_mem_attributes() Message-ID: <20150813082207.GB14610@gmail.com> References: <1439396234-22863-1-git-send-email-matt@codeblueprint.co.uk> <1439396234-22863-2-git-send-email-matt@codeblueprint.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1439396234-22863-2-git-send-email-matt@codeblueprint.co.uk> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2741 Lines: 83 * Matt Fleming wrote: > From: "Jonathan (Zhixiong) Zhang" > > Table 8 of UEFI 2.5 section 2.3.6.1 defines mappings from EFI > memory types to MAIR attribute encodings for arm64. > > If the physical address has memory attributes defined by EFI > memmap as EFI_MEMORY_[UC|WC|WT], return approprate page protection > type according to the UEFI spec. Otherwise, return PAGE_KERNEL. > > Reviewed-by: Catalin Marinas > Acked-by: Hanjun Guo > Reviewed-by: Ard Biesheuvel > Signed-off-by: Jonathan (Zhixiong) Zhang > Signed-off-by: Matt Fleming > --- > arch/arm64/include/asm/acpi.h | 30 ++++++++++++++++++++++++++++++ > 1 file changed, 30 insertions(+) > > diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h > index 406485ed110a..1cbad43e561d 100644 > --- a/arch/arm64/include/asm/acpi.h > +++ b/arch/arm64/include/asm/acpi.h > @@ -19,6 +19,11 @@ > #include > #include > > +#ifdef CONFIG_ACPI_APEI > +#include > +#include > +#endif > + > /* Macros for consistency checks of the GICC subtable of MADT */ > #define ACPI_MADT_GICC_LENGTH \ > (acpi_gbl_FADT.header.revision < 6 ? 76 : 80) > @@ -92,4 +97,29 @@ static inline const char *acpi_get_enable_method(int cpu) > { > return acpi_psci_present() ? "psci" : NULL; > } > + > +#ifdef CONFIG_ACPI_APEI > +static inline pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr) > +{ > + /* > + * According to "Table 8 Map: EFI memory types to AArch64 memory types" > + * of UEFI 2.5 section 2.3.6.1, each EFI memory type is mapped to > + * corresponding MAIR attribute encoding. s/mapped to corresponding/ mapped to a corresponding > + * The EFI memory attribute advises all possible capabilities of a > + * memory region. We use the most efficient capability. > + */ > + > + u64 attr; > + > + attr = efi_mem_attributes(addr); > + if (attr & EFI_MEMORY_WB) > + return PAGE_KERNEL; > + if (attr & EFI_MEMORY_WT) > + return __pgprot(PROT_NORMAL_WT); > + if (attr & EFI_MEMORY_WC) > + return __pgprot(PROT_NORMAL_NC); > + return __pgprot(PROT_DEVICE_nGnRnE); > +} > +#endif Also, this doesn't look like a small function - why is it inlined? Moving it to .c would also slightly improve compilation times for every .c file that includes asm/acpi.h. Thanks, Ingo -- 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/