Merge remote-tracking branch 'pm/linux-next'

[karo-tx-linux.git] / arch / arm64 / kernel / acpi.c

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index d6463bba2360561e59acb1f0fa5dbac926f37dfa..d1ce8e2f98b99bcb1fba0bae25c08e8f851c4f4b 100644 (file)
--- 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);
@@ -205,3 +210,27 @@ void __init acpi_boot_table_init(void)
                        disable_acpi();
        }
 }
+
+#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