ACPI/ADXL: Add address translation interface using an ACPI DSM

Some new Intel servers provide an interface so that the OS can ask the
BIOS to translate a system physical address to a memory address (socket,
memory controller, channel, rank, dimm, etc.). This is useful for EDAC
drivers that want to take the address of an error reported in a machine
check bank and let the user know which DIMM may need to be replaced.

Specification for this interface is available at:

  https://cdrdv2.intel.com/v1/dl/getContent/603354

 [ Based on earlier code by Qiuxu Zhuo <qiuxu.zhuo@intel.com>. ]

 [ bp: Make the first pr_info() in adxl_init() pr_debug() so that it
   doesn't pollute every dmesg. ]

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
CC: Len Brown <lenb@kernel.org>
CC: linux-acpi@vger.kernel.org
CC: linux-edac@vger.kernel.org
Link: http://lkml.kernel.org/r/20181015202620.23610-1-tony.luck@intel.com

include/linux/adxl.h

@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Address translation interface via ACPI DSM.
+ * Copyright (C) 2018 Intel Corporation
+ */
+
+#ifndef _LINUX_ADXL_H
+#define _LINUX_ADXL_H
+
+const char * const *adxl_get_component_names(void);
+int adxl_decode(u64 addr, u64 component_values[]);
+
+#endif /* _LINUX_ADXL_H */