Linux-libre 4.4-gnupck-4.4-gnu

1 files changed, 24 insertions, 20 deletions

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index 19de7537e..d1ce8e2f9 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);
@@ -206,27 +211,26 @@ void __init acpi_boot_table_init(void)
 	}
 }
 
-void __init acpi_gic_init(void)
+#ifdef CONFIG_ACPI_APEI
+pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
 {
-	struct acpi_table_header *table;
-	acpi_status status;
-	acpi_size tbl_size;
-	int err;
-
-	if (acpi_disabled)
-		return;
-
-	status = acpi_get_table_with_size(ACPI_SIG_MADT, 0, &table, &tbl_size);
-	if (ACPI_FAILURE(status)) {
-		const char *msg = acpi_format_exception(status);
-
-		pr_err("Failed to get MADT table, %s\n", msg);
-		return;
-	}
+	/*
+	 * 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.
+	 */
 
-	err = gic_v2_acpi_init(table);
-	if (err)
-		pr_err("Failed to initialize GIC IRQ controller");
+	u64 attr;
 
-	early_acpi_os_unmap_memory((char *)table, tbl_size);
+	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