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| author |   Jonathan (Zhixiong) Zhang <zjzhang@codeaurora.org> | 2015-09-04 14:11:41 +0100 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2015-09-14 11:40:03 +0200 |
| commit | 89e44b51cc0db50ea4b5bbb5d582c4db88bbaed8 (patch) | |
| tree | 0a47165178fb3130382db1ebfc1516537ea8623f /arch/arm64/kernel/acpi.c | |
| parent | arm64/mm: Add PROT_DEVICE_nGnRnE and PROT_NORMAL_WT (diff) | |
| download | linux-dev-89e44b51cc0db50ea4b5bbb5d582c4db88bbaed8.tar.xz linux-dev-89e44b51cc0db50ea4b5bbb5d582c4db88bbaed8.zip | |
arm64, acpi/apei: Implement arch_apei_get_mem_attributes()
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.
Signed-off-by: Jonathan (Zhixiong) Zhang <zjzhang@codeaurora.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
[ Small stylistic tweaks. ]
Reviewed-by: Matt Fleming <matt.fleming@intel.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1441372302-23242-2-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/arm64/kernel/acpi.c')
| -rw-r--r-- | arch/arm64/kernel/acpi.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index 19de7537e7d3..137d537ddceb 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -29,6 +29,11 @@ #include <asm/cpu_ops.h> #include <asm/smp_plat.h> +#ifdef CONFIG_ACPI_APEI +# include <linux/efi.h> +# include <asm/pgtable.h> +#endif + int acpi_noirq = 1; /* skip ACPI IRQ initialization */ int acpi_disabled = 1; EXPORT_SYMBOL(acpi_disabled); @@ -230,3 +235,27 @@ void __init acpi_gic_init(void) early_acpi_os_unmap_memory((char *)table, tbl_size); } + +#ifdef CONFIG_ACPI_APEI +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 a 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 |