EDAC/igen6: Add EDAC driver for Intel client SoCs using IBECC

This driver supports Intel client SoC with integrated memory controller
using In-Band ECC(IBECC). The memory correctable and uncorrectable errors
are reported via NMIs. The driver handles the NMIs and decodes the memory
error address to platform specific address. The first IBECC-supported SoC
is Elkhart Lake.

[Tony: s/#include <linux/nmi.h>/#include <asm/nmi.h>/ to fix randconfig build]
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

drivers/edac/Kconfig

@@ -269,6 +269,15 @@ config EDAC_PND2
 	  first used on the Apollo Lake platform and Denverton
 	  micro-server but may appear on others in the future.
 
+config EDAC_IGEN6
+	tristate "Intel client SoC Integrated MC"
+	depends on PCI && X86_64 && PCI_MMCONFIG && ARCH_HAVE_NMI_SAFE_CMPXCHG
+	help
+	  Support for error detection and correction on the Intel
+	  client SoC Integrated Memory Controller using In-Band ECC IP.
+	  This In-Band ECC is first used on the Elkhart Lake SoC but
+	  may appear on others in the future.
+
 config EDAC_MPC85XX
 	bool "Freescale MPC83xx / MPC85xx"
 	depends on FSL_SOC && EDAC=y

drivers/edac/Makefile

@@ -32,6 +32,7 @@ obj-$(CONFIG_EDAC_I7300)		+= i7300_edac.o
 obj-$(CONFIG_EDAC_I7CORE)		+= i7core_edac.o
 obj-$(CONFIG_EDAC_SBRIDGE)		+= sb_edac.o
 obj-$(CONFIG_EDAC_PND2)			+= pnd2_edac.o
+obj-$(CONFIG_EDAC_IGEN6)			+= igen6_edac.o
 obj-$(CONFIG_EDAC_E7XXX)		+= e7xxx_edac.o
 obj-$(CONFIG_EDAC_E752X)		+= e752x_edac.o
 obj-$(CONFIG_EDAC_I82443BXGX)		+= i82443bxgx_edac.o