ACPI: add config for BIOS table scan

With the addition of ARM64 that does not have a traditional BIOS to
scan, add a config option which is selected on x86 (ia64 doesn't need
it either, it is EFI/UEFI based system) to do the traditional BIOS
scanning for tables.

Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index d24887b..5617750 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -132,6 +132,7 @@ config X86
        select GENERIC_CPU_AUTOPROBE
        select HAVE_ARCH_AUDITSYSCALL
        select ARCH_SUPPORTS_ATOMIC_RMW
+       select ACPI_LEGACY_TABLES_LOOKUP if ACPI
 
 config INSTRUCTION_DECODER
        def_bool y

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index a34a228..970524c 100644 (file)
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -42,6 +42,9 @@ menuconfig ACPI
 
 if ACPI
 
+config ACPI_LEGACY_TABLES_LOOKUP
+       bool
+
 config ACPI_SLEEP
        bool
        depends on SUSPEND || HIBERNATION

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index bad25b0..3abe9b2 100644 (file)
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -259,12 +259,14 @@ acpi_physical_address __init acpi_os_get_root_pointer(void)
                               "System description tables not found\n");
                        return 0;
                }
-       } else {
+       } else if (IS_ENABLED(CONFIG_ACPI_LEGACY_TABLES_LOOKUP)) {
                acpi_physical_address pa = 0;
 
                acpi_find_root_pointer(&pa);
                return pa;
        }
+
+       return 0;
 }
 
 /* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */