Basically, there are full memory mirroring and address range partial
memory mirroring (supported by Haswell EX and Broadwell EX) modes.

a) In full memory mirroring, the memory behind each memory controller
   is mirrored, i.e. the memory is split into two identical mirrors
   (primary and secondary), half of the memory is reserved for redundancy.

b) In address range partial memory mirroring, the memory size (range)
   of primary and secondary behind each memory controller can be user
   defined by the TAD0 register. The rest of memory ranges defined by
   TAD1/TAD2/... in that memory controller are non-mirrored.

For more detail on memory mirroring, see the following link written by Tony Luck:

  https://01.org/lkp/blogs/tonyluck/2016/address-range-partial-memory-mirroring-linux

Currently the sb_edac driver only supports address decoding in full
memory mirroring and non-mirroring modes. In address range partial
memory mirroring mode, it may fail to decode an address that falls in a
non-mirroring area (the following was one of this kind of failed logs).

  mce: Uncorrected hardware memory error in user-access at 566d53a400
  Memory failure: 0x566d53a8: Killing einj_mem_uc:4647 due to hardware memory corruption
  Memory failure: 0x566d53a8: recovery action for dirty LRU page: Recovered
  mce: [Hardware Error]: Machine check events logged
  EDAC sbridge MC1: HANDLING MCE MEMORY ERROR
  EDAC sbridge MC1: CPU 48: Machine Check Event: 0 Bank 7: ec00000000010090
  EDAC sbridge MC1: TSC 4b914aa5a99dab
  EDAC sbridge MC1: ADDR 566d53a400
  EDAC sbridge MC1: MISC 1443a0c86
  EDAC sbridge MC1: PROCESSOR 0:406f1 TIME 1499712764 SOCKET 2 APIC 80
  EDAC MC1: 0 UE Can't discover the memory rank for ch addr 0x7fb54e900 on any memory ( page:0x0 offset:0x0 grain:32)
  mce: [Hardware Error]: Machine check events logged

Therefore, classify memory mirroring modes and make the address decoding
in address range partial memory mode correct.
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170730180651.30060-1-qiuxu.zhuo@intel.comSigned-off-by: Borislav Petkov <bp@suse.de>