ghes_edac: Register at EDAC core the BIOS report

Register GHES at EDAC MC core, in order to avoid other
drivers to also handle errors and mangle with error data.

The edac core will warrant that just one driver will be used,
so the first one to register (BIOS first) will be the one that
will be reporting the hardware errors.

For now, the EDAC driver does nothing but to register at the
EDAC core, preventing the hardware-driven mechanism to
interfere with GHES.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 66719925970f..7e38e5e576e8 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -80,6 +80,29 @@ config EDAC_MM_EDAC
           occurred so that a particular failing memory module can be
           replaced.  If unsure, select 'Y'.
 
+config EDAC_GHES
+        bool "Output ACPI APEI/GHES BIOS detected errors via EDAC"
+        depends on ACPI_APEI_GHES && (EDAC_MM_EDAC=y)
+        default y
+        help
+          Not all machines support hardware-driven error report. Some of those
+          provide a BIOS-driven error report mechanism via ACPI, using the
+          APEI/GHES driver. By enabling this option, the error reports provided
+          by GHES are sent to userspace via the EDAC API.
+
+          When this option is enabled, it will disable the hardware-driven
+          mechanisms, if a GHES BIOS is detected, entering into the
+          "Firmware First" mode.
+
+          It should be noticed that keeping both GHES and a hardware-driven
+          error mechanism won't work well, as BIOS will race with OS, while
+          reading the error registers. So, if you want to not use "Firmware
+          first" GHES error mechanism, you should disable GHES either at
+          compilation time or by passing "ghes.disable=1" Kernel parameter
+          at boot time.
+
+          In doubt, say 'Y'.
+
 config EDAC_AMD64
         tristate "AMD64 (Opteron, Athlon64) K8, F10h"
         depends on EDAC_MM_EDAC && AMD_NB && X86_64 && EDAC_DECODE_MCE