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>
This commit is contained in:
Jonathan (Zhixiong) Zhang 2015-09-04 14:11:41 +01:00 committed by Ingo Molnar
parent 8d446c8647
commit 89e44b51cc
2 changed files with 34 additions and 0 deletions

View File

@ -92,4 +92,9 @@ static inline const char *acpi_get_enable_method(int cpu)
{
return acpi_psci_present() ? "psci" : NULL;
}
#ifdef CONFIG_ACPI_APEI
pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr);
#endif
#endif /*_ASM_ACPI_H*/

View File

@ -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