Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754936AbbHLQRn (ORCPT ); Wed, 12 Aug 2015 12:17:43 -0400 Received: from mail-wi0-f169.google.com ([209.85.212.169]:35006 "EHLO mail-wi0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754588AbbHLQRi (ORCPT ); Wed, 12 Aug 2015 12:17:38 -0400 From: Matt Fleming To: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" Cc: "Jonathan (Zhixiong) Zhang" , linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, Matt Fleming , Ard Biesheuvel , Catalin Marinas , Hanjun Guo Subject: [PATCH 1/2] arm64: apei: implement arch_apei_get_mem_attributes() Date: Wed, 12 Aug 2015 17:17:13 +0100 Message-Id: <1439396234-22863-2-git-send-email-matt@codeblueprint.co.uk> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1439396234-22863-1-git-send-email-matt@codeblueprint.co.uk> References: <1439396234-22863-1-git-send-email-matt@codeblueprint.co.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2354 Lines: 72 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. + * 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 + #endif /*_ASM_ACPI_H*/ -- 2.1.0 -- 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/