bcbd069b - EDAC: Add a Error Check Scrub control feature

Wed, 12 Feb 2025 14:36:41 +0000

EDAC: Add a Error Check Scrub control featureAdd an Error Check Scrub (ECS) control to manage a memory device's ECSfeature.The ECS is a feature defined in JEDEC DDR5 SDRAM Specification (JESD79-5) andallows the DRAM to internally read, correct single-bit errors, and write backcorrected data bits to the DRAM array while providing transparency to errorcounts.The DDR5 device contains a number of memory media Field Replaceable Units(FRU) per device. The DDR5 ECS feature and thus the ECS control driversupports configuring the ECS parameters per FRU.Memory devices support the ECS feature register with the EDAC device driver,which retrieves the ECS descriptor from the EDAC ECS driver. This driverexposes sysfs ECS control attributes to userspace via /sys/bus/edac/devices//ecs_fruX/.The common sysfs ECS control interface abstracts the control of an arbitraryECS functionality to a common set of functions.Support for the ECS feature is added separately because the control attributesof the DDR5 ECS feature differ from those of the scrub feature.The sysfs ECS attribute nodes are only present if the client driver hasimplemented the corresponding attribute callback function and passed thenecessary operations to the EDAC RAS feature driver during registration. [ bp: Massage, fixup edac_dev_register() retvals. ]Co-developed-by: Jonathan Cameron Signed-off-by: Jonathan Cameron Signed-off-by: Shiju Jose Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Fan Ni Tested-by: Fan Ni Link: https://lore.kernel.org/r/20250212143654.1893-4-shiju.jose@huawei.com List of files: /linux-6.15/Documentation/ABI/testing/sysfs-edac-ecs

Changes in sysfs-edac-ecs

bcbd069b - EDAC: Add a Error Check Scrub control feature