Em Mon, 6 Jan 2025 12:09:58 +0000 <shiju.jose@xxxxxxxxxx> escreveu: > From: Shiju Jose <shiju.jose@xxxxxxxxxx> > > Add a generic EDAC scrub control to manage memory scrubbers in the system. > Devices with a scrub feature register with the EDAC device driver, which > retrieves the scrub descriptor from the EDAC scrub driver and exposes the > sysfs scrub control attributes for a scrub instance to userspace at > /sys/bus/edac/devices/<dev-name>/scrubX/. > > The common sysfs scrub control interface abstracts the control of > arbitrary scrubbing functionality into a common set of functions. The > sysfs scrub attribute nodes are only present if the client driver has > implemented the corresponding attribute callback function and passed the > operations(ops) to the EDAC device driver during registration. > > Co-developed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > Signed-off-by: Shiju Jose <shiju.jose@xxxxxxxxxx> > --- > Documentation/ABI/testing/sysfs-edac-scrub | 74 +++++++ > Documentation/edac/features.rst | 5 + > Documentation/edac/index.rst | 1 + > Documentation/edac/scrub.rst | 244 +++++++++++++++++++++ > drivers/edac/Makefile | 1 + > drivers/edac/edac_device.c | 41 +++- > drivers/edac/scrub.c | 209 ++++++++++++++++++ > include/linux/edac.h | 34 +++ > 8 files changed, 605 insertions(+), 4 deletions(-) > create mode 100644 Documentation/ABI/testing/sysfs-edac-scrub > create mode 100644 Documentation/edac/scrub.rst > create mode 100755 drivers/edac/scrub.c > > diff --git a/Documentation/ABI/testing/sysfs-edac-scrub b/Documentation/ABI/testing/sysfs-edac-scrub > new file mode 100644 > index 000000000000..af14a68ee5a9 > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-edac-scrub > @@ -0,0 +1,74 @@ > +What: /sys/bus/edac/devices/<dev-name>/scrubX > +Date: Jan 2025 > +KernelVersion: 6.14 > +Contact: linux-edac@xxxxxxxxxxxxxxx > +Description: > + The sysfs EDAC bus devices /<dev-name>/scrubX subdirectory > + belongs to an instance of memory scrub control feature, > + where <dev-name> directory corresponds to a device/memory > + region registered with the EDAC device driver for the > + scrub control feature. > + The sysfs scrub attr nodes are only present if the parent > + driver has implemented the corresponding attr callback > + function and provided the necessary operations to the EDAC > + device driver during registration. > + > +What: /sys/bus/edac/devices/<dev-name>/scrubX/addr > +Date: Jan 2025 > +KernelVersion: 6.14 > +Contact: linux-edac@xxxxxxxxxxxxxxx > +Description: > + (RW) The base address of the memory region to be scrubbed > + for on-demand scrubbing. Setting address would start > + scrubbing. The size must be set before that. > + The readback addr value would be non-zero if the requested > + on-demand scrubbing is in progress, zero otherwise. > + > +What: /sys/bus/edac/devices/<dev-name>/scrubX/size > +Date: Jan 2025 > +KernelVersion: 6.14 > +Contact: linux-edac@xxxxxxxxxxxxxxx > +Description: > + (RW) The size of the memory region to be scrubbed > + (on-demand scrubbing). > + > +What: /sys/bus/edac/devices/<dev-name>/scrubX/enable_background > +Date: Jan 2025 > +KernelVersion: 6.14 > +Contact: linux-edac@xxxxxxxxxxxxxxx > +Description: > + (RW) Start/Stop background(patrol) scrubbing if supported. > + > +What: /sys/bus/edac/devices/<dev-name>/scrubX/enable_on_demand > +Date: Jan 2025 > +KernelVersion: 6.14 > +Contact: linux-edac@xxxxxxxxxxxxxxx > +Description: > + (RW) Start/Stop on-demand scrubbing the memory region > + if supported. > + > +What: /sys/bus/edac/devices/<dev-name>/scrubX/min_cycle_duration > +Date: Jan 2025 > +KernelVersion: 6.14 > +Contact: linux-edac@xxxxxxxxxxxxxxx > +Description: > + (RO) Supported minimum scrub cycle duration in seconds > + by the memory scrubber. > + > +What: /sys/bus/edac/devices/<dev-name>/scrubX/max_cycle_duration > +Date: Jan 2025 > +KernelVersion: 6.14 > +Contact: linux-edac@xxxxxxxxxxxxxxx > +Description: > + (RO) Supported maximum scrub cycle duration in seconds > + by the memory scrubber. > + > +What: /sys/bus/edac/devices/<dev-name>/scrubX/current_cycle_duration > +Date: Jan 2025 > +KernelVersion: 6.14 > +Contact: linux-edac@xxxxxxxxxxxxxxx > +Description: > + (RW) The current scrub cycle duration in seconds and must be > + within the supported range by the memory scrubber. > + Scrub has an overhead when running and that may want to be > + reduced by taking longer to do it. > diff --git a/Documentation/edac/features.rst b/Documentation/edac/features.rst > index f32f259ce04d..ba3ab993ee4f 100644 > --- a/Documentation/edac/features.rst > +++ b/Documentation/edac/features.rst > @@ -92,3 +92,8 @@ the sysfs EDAC bus. For example, /sys/bus/edac/devices/<dev-name>/<feature>X/ > 3. RAS dynamic feature controller - Userspace sample modules in rasdaemon for > dynamic scrub/repair control to issue scrubbing/repair when excess number > of corrected memory errors are reported in a short span of time. > + > +RAS features > +------------ > +1. Memory Scrub > +Memory scrub features are documented in `Documentation/edac/scrub.rst`. > diff --git a/Documentation/edac/index.rst b/Documentation/edac/index.rst > index b6c265a4cffb..dfb0c9fb9ab1 100644 > --- a/Documentation/edac/index.rst > +++ b/Documentation/edac/index.rst > @@ -8,3 +8,4 @@ EDAC Subsystem > :maxdepth: 1 > > features > + scrub > diff --git a/Documentation/edac/scrub.rst b/Documentation/edac/scrub.rst > new file mode 100644 > index 000000000000..5a5108b744a4 > --- /dev/null > +++ b/Documentation/edac/scrub.rst > @@ -0,0 +1,244 @@ > +.. SPDX-License-Identifier: GPL-2.0 Same note of patch 1, e. g.: .. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.2-no-invariants-or-later > + > +=================== > +EDAC Scrub Control > +=================== > + > +Copyright (c) 2024 HiSilicon Limited. > + > +:Author: Shiju Jose <shiju.jose@xxxxxxxxxx> > +:License: The GNU Free Documentation License, Version 1.2 > + (dual licensed under the GPL v2) See my notes on patch 1. I won't repeat those over the other patches in this series touching documentation > +:Original Reviewers: > + > +- Written for: 6.14 > + > +Introduction > +------------ > +Increasing DRAM size and cost have made memory subsystem reliability an > +important concern. These modules are used where potentially corrupted data > +could cause expensive or fatal issues. Memory errors are among the top > +hardware failures that cause server and workload crashes. > + > +Memory scrubbing is a feature where an ECC (Error-Correcting Code) engine > +reads data from each memory media location, corrects with an ECC if > +necessary and writes the corrected data back to the same memory media > +location. > + > +The memory DIMMs can be scrubbed at a configurable rate to detect > +uncorrected memory errors and attempt recovery from detected errors, > +providing the following benefits. > + > +* Proactively scrubbing memory DIMMs reduces the chance of a correctable error becoming uncorrectable. > + > +* When detected, uncorrected errors caught in unallocated memory pages are isolated and prevented from being allocated to an application or the OS. > + > +* This reduces the likelihood of software or hardware products encountering memory errors. > + > +There are 2 types of memory scrubbing: > + > +1. Background (patrol) scrubbing of the RAM while the RAM is otherwise > +idle. > + > +2. On-demand scrubbing for a specific address range or region of memory. > + > +Several types of interfaces to hardware memory scrubbers have been > +identified, such as CXL memory device patrol scrub, CXL DDR5 ECS, ACPI > +RAS2 memory scrubbing, and ACPI NVDIMM ARS (Address Range Scrub). > + > +The scrub control varies between different memory scrubbers. To allow > +for standard userspace tooling there is a need to present these controls > +with a standard ABI. > + > +The control mechanisms vary across different memory scrubbers. To enable > +standardized userspace tooling, there is a need to present these controls > +through a standardized ABI. > + > +Introduce a generic memory EDAC scrub control that allows users to manage > +underlying scrubbers in the system through a standardized sysfs scrub > +control interface. This common sysfs scrub control interface abstracts the > +management of various scrubbing functionalities into a unified set of > +functions. > + > +Use cases of common scrub control feature > +----------------------------------------- > +1. Several types of interfaces for hardware (HW) memory scrubbers have > +been identified, including the CXL memory device patrol scrub, CXL DDR5 > +ECS, ACPI RAS2 memory scrubbing features, ACPI NVDIMM ARS (Address Range > +Scrub), and software-based memory scrubbers. Some of these scrubbers > +support control over patrol (background) scrubbing (e.g., ACPI RAS2, CXL) > +and/or on-demand scrubbing (e.g., ACPI RAS2, ACPI ARS). However, the scrub > +control interfaces vary between memory scrubbers, highlighting the need for > +a standardized, generic sysfs scrub control interface that is accessible to > +userspace for administration and use by scripts/tools. > + > +2. User-space scrub controls allow users to disable scrubbing if necessary, > +for example, to disable background patrol scrubbing or adjust the scrub > +rate for performance-aware operations where background activities need to > +be minimized or disabled. > + > +3. User-space tools enable on-demand scrubbing for specific address ranges, > +provided that the scrubber supports this functionality. > + > +4. User-space tools can also control memory DIMM scrubbing at a configurable > +scrub rate via sysfs scrub controls. This approach offers several benefits: > + > +* Detects uncorrectable memory errors early, before user access to affected memory, helping facilitate recovery. > + > +* Reduces the likelihood of correctable errors developing into uncorrectable errors. > + > +5. Policy control for hotplugged memory is necessary because there may not > +be a system-wide BIOS or similar control to manage scrub settings for a CXL > +device added after boot. Determining these settings is a policy decision, > +balancing reliability against performance, so userspace should control it. > +Therefore, a unified interface is recommended for handling this function in > +a way that aligns with other similar interfaces, rather than creating a > +separate one. > + > +Scrubbing features > +------------------ > +Comparison of various scrubbing features:: > + > + ................................................................ > + . . ACPI . CXL patrol. CXL ECS . ARS . > + . Name . RAS2 . scrub . . . > + ................................................................ > + . . . . . . > + . On-demand . Supported . No . No . Supported . > + . Scrubbing . . . . . > + . . . . . . > + ................................................................ > + . . . . . . > + . Background . Supported . Supported . Supported . No . > + . scrubbing . . . . . > + . . . . . . > + ................................................................ > + . . . . . . > + . Mode of . Scrub ctrl. per device. per memory. Unknown . > + . scrubbing . per NUMA . . media . . > + . . domain. . . . . > + ................................................................ > + . . . . . . > + . Query scrub . Supported . Supported . Supported . Supported . > + . capabilities . . . . . > + . . . . . . > + ................................................................ > + . . . . . . > + . Setting . Supported . No . No . Supported . > + . address range. . . . . > + . . . . . . > + ................................................................ > + . . . . . . > + . Setting . Supported . Supported . No . No . > + . scrub rate . . . . . > + . . . . . . > + ................................................................ > + . . . . . . > + . Unit for . Not . in hours . No . No . > + . scrub rate . Defined . . . . > + . . . . . . > + ................................................................ > + . . Supported . . . . > + . Scrub . on-demand . No . No . Supported . > + . status/ . scrubbing . . . . > + . Completion . only . . . . > + ................................................................ > + . UC error . .CXL general.CXL general. ACPI UCE . > + . reporting . Exception .media/DRAM .media/DRAM . notify and. > + . . .event/media.event/media. query . > + . . .scan? .scan? . ARS status. > + ................................................................ > + . . . . . . > + . Support for . Supported . Supported . Supported . No . > + . EDAC control . . . . . > + . . . . . . > + ................................................................ Please format this as a table, in ReST, e. g: Scrubbing features ------------------ Comparison of various scrubbing features: +--------------+-----------+-----------+-----------+-----------+ | | | | | | | Background | Supported | Supported | Supported | No | | scrubbing | | | | | | | | | | | +==============+===========+===========+===========+===========+ | | | | | | | Mode of | Scrub ctrl| per device| per memory| Unknown | | scrubbing | per NUMA | | media | | | | domain | | | | +--------------+-----------+-----------+-----------+-----------+ | | | | | | | Query scrub | Supported | Supported | Supported | Supported | | capabilities | | | | | | | | | | | +--------------+-----------+-----------+-----------+-----------+ | | | | | | | Setting | Supported | No | No | Supported | | address range| | | | | | | | | | | +--------------+-----------+-----------+-----------+-----------+ | | | | | | | Setting | Supported | Supported | No | No | | scrub rate | | | | | | | | | | | +--------------+-----------+-----------+-----------+-----------+ | | | | | | | Unit for | Not | in hours | No | No | | scrub rate | Defined | | | | | | | | | | +--------------+-----------+-----------+-----------+-----------+ | | Supported | | | | | Scrub | on-demand | No | No | Supported | | status/ | scrubbing | | | | | Completion | only | | | | +--------------+-----------+-----------+-----------+-----------+ | UC error | |CXL general|CXL general| ACPI UCE | | reporting | Exception |media/DRAM |media/DRAM | notify and| | | |event/media|event/media| query | | | |scan? |scan? | ARS status| +--------------+-----------+-----------+-----------+-----------+ | | | | | | | Support for | Supported | Supported | Supported | No | | EDAC control | | | | | | | | | | | +--------------+-----------+-----------+-----------+-----------+ > +CXL Memory Scrubbing features > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > +CXL spec r3.1 section 8.2.9.9.11.1 describes the memory device patrol scrub > +control feature. The device patrol scrub proactively locates and makes > +corrections to errors in regular cycle. The patrol scrub control allows the > +request to configure patrol scrubber's input configurations. > + > +The patrol scrub control allows the requester to specify the number of > +hours in which the patrol scrub cycles must be completed, provided that > +the requested number is not less than the minimum number of hours for the > +patrol scrub cycle that the device is capable of. In addition, the patrol > +scrub controls allow the host to disable and enable the feature in case > +disabling of the feature is needed for other purposes such as > +performance-aware operations which require the background operations to be > +turned off. > + > +Error Check Scrub (ECS) > +~~~~~~~~~~~~~~~~~~~~~~~ > +CXL spec r3.1 section 8.2.9.9.11.2 describes the Error Check Scrub (ECS) > +is a feature defined in JEDEC DDR5 SDRAM Specification (JESD79-5) and > +allows the DRAM to internally read, correct single-bit errors, and write > +back corrected data bits to the DRAM array while providing transparency > +to error counts. Please add a reference for CXL spec, like: CXL spec r3.1 [1]_ section 8.2.9.9.11.2 describes... .. [1] https://computeexpresslink.org/wp-content/uploads/2024/02/CXL-3.1-Specification.pdf Same for other specs mentioned at the docs. For more details, see: https://www.sphinx-doc.org/en/master/usage/restructuredtext/basics.html#footnotes > + > +The DDR5 device contains number of memory media FRUs per device. The > +DDR5 ECS feature and thus the ECS control driver supports configuring > +the ECS parameters per FRU. > + > +ACPI RAS2 Hardware-based Memory Scrubbing > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > +ACPI spec 6.5 section 5.2.21 ACPI RAS2 describes ACPI RAS2 table > +provides interfaces for platform RAS features and supports independent > +RAS controls and capabilities for a given RAS feature for multiple > +instances of the same component in a given system. > +Memory RAS features apply to RAS capabilities, controls and operations > +that are specific to memory. RAS2 PCC sub-spaces for memory-specific RAS > +features have a Feature Type of 0x00 (Memory). > + > +The platform can use the hardware-based memory scrubbing feature to expose > +controls and capabilities associated with hardware-based memory scrub > +engines. The RAS2 memory scrubbing feature supports following as per spec, > + > +* Independent memory scrubbing controls for each NUMA domain, identified using its proximity domain. > + > +* Provision for background (patrol) scrubbing of the entire memory system, as well as on-demand scrubbing for a specific region of memory. > + > +ACPI Address Range Scrubbing(ARS) > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > +ACPI spec 6.5 section 9.19.7.2 describes Address Range Scrubbing(ARS). > +ARS allows the platform to communicate memory errors to system software. > +This capability allows system software to prevent accesses to addresses > +with uncorrectable errors in memory. ARS functions manage all NVDIMMs > +present in the system. Only one scrub can be in progress system wide > +at any given time. > +Following functions are supported as per the specification. > + > +1. Query ARS Capabilities for a given address range, indicates platform > +supports the ACPI NVDIMM Root Device Unconsumed Error Notification. > + > +2. Start ARS triggers an Address Range Scrub for the given memory range. > +Address scrubbing can be done for volatile memory, persistent memory, or both. > + > +3. Query ARS Status command allows software to get the status of ARS, > +including the progress of ARS and ARS error record. > + > +4. Clear Uncorrectable Error. > + > +5. Translate SPA > + > +6. ARS Error Inject etc. > + > +The kernel supports an existing control for ARS and ARS is currently not > +supported in EDAC. > + > +The File System > +--------------- > + > +The control attributes of a registered scrubber instance could be > +accessed in the > + > +/sys/bus/edac/devices/<dev-name>/scrubX/ > + > +sysfs > +----- > + > +Sysfs files are documented in > + > +`Documentation/ABI/testing/sysfs-edac-scrub`. Please remove the blank line, e. g.: Sysfs files are documented in `Documentation/ABI/testing/sysfs-edac-scrub`. > diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile > index f9cf19d8d13d..a162726cc6b9 100644 > --- a/drivers/edac/Makefile > +++ b/drivers/edac/Makefile > @@ -10,6 +10,7 @@ obj-$(CONFIG_EDAC) := edac_core.o > > edac_core-y := edac_mc.o edac_device.o edac_mc_sysfs.o > edac_core-y += edac_module.o edac_device_sysfs.o wq.o > +edac_core-y += scrub.o > > edac_core-$(CONFIG_EDAC_DEBUG) += debugfs.o > > diff --git a/drivers/edac/edac_device.c b/drivers/edac/edac_device.c > index 9fce46dd7405..60b20eae01e8 100644 > --- a/drivers/edac/edac_device.c > +++ b/drivers/edac/edac_device.c > @@ -575,6 +575,7 @@ static void edac_dev_release(struct device *dev) > { > struct edac_dev_feat_ctx *ctx = container_of(dev, struct edac_dev_feat_ctx, dev); > > + kfree(ctx->scrub); > kfree(ctx->dev.groups); > kfree(ctx); > } > @@ -608,8 +609,10 @@ int edac_dev_register(struct device *parent, char *name, > const struct edac_dev_feature *ras_features) > { > const struct attribute_group **ras_attr_groups; > + struct edac_dev_data *dev_data; > struct edac_dev_feat_ctx *ctx; > int attr_gcnt = 0; > + int scrub_cnt = 0; > int ret, feat; > > if (!parent || !name || !num_features || !ras_features) > @@ -618,7 +621,10 @@ int edac_dev_register(struct device *parent, char *name, > /* Double parse to make space for attributes */ > for (feat = 0; feat < num_features; feat++) { > switch (ras_features[feat].ft_type) { > - /* Add feature specific code */ > + case RAS_FEAT_SCRUB: > + attr_gcnt++; > + scrub_cnt++; > + break; > default: > return -EINVAL; > } > @@ -634,13 +640,38 @@ int edac_dev_register(struct device *parent, char *name, > goto ctx_free; > } > > + if (scrub_cnt) { > + ctx->scrub = kcalloc(scrub_cnt, sizeof(*ctx->scrub), GFP_KERNEL); > + if (!ctx->scrub) { > + ret = -ENOMEM; > + goto groups_free; > + } > + } > + > attr_gcnt = 0; > + scrub_cnt = 0; > for (feat = 0; feat < num_features; feat++, ras_features++) { > switch (ras_features->ft_type) { > - /* Add feature specific code */ > + case RAS_FEAT_SCRUB: > + if (!ras_features->scrub_ops || > + scrub_cnt != ras_features->instance) > + goto data_mem_free; > + > + dev_data = &ctx->scrub[scrub_cnt]; > + dev_data->instance = scrub_cnt; > + dev_data->scrub_ops = ras_features->scrub_ops; > + dev_data->private = ras_features->ctx; > + ret = edac_scrub_get_desc(parent, &ras_attr_groups[attr_gcnt], > + ras_features->instance); > + if (ret) > + goto data_mem_free; > + > + scrub_cnt++; > + attr_gcnt++; > + break; > default: > ret = -EINVAL; > - goto groups_free; > + goto data_mem_free; > } > } > > @@ -653,7 +684,7 @@ int edac_dev_register(struct device *parent, char *name, > > ret = dev_set_name(&ctx->dev, name); > if (ret) > - goto groups_free; > + goto data_mem_free; > > ret = device_register(&ctx->dev); > if (ret) { > @@ -663,6 +694,8 @@ int edac_dev_register(struct device *parent, char *name, > > return devm_add_action_or_reset(parent, edac_dev_unreg, &ctx->dev); > > +data_mem_free: > + kfree(ctx->scrub); > groups_free: > kfree(ras_attr_groups); > ctx_free: > diff --git a/drivers/edac/scrub.c b/drivers/edac/scrub.c > new file mode 100755 > index 000000000000..3978201c4bfc > --- /dev/null > +++ b/drivers/edac/scrub.c > @@ -0,0 +1,209 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * The generic EDAC scrub driver controls the memory scrubbers in the > + * system. The common sysfs scrub interface abstracts the control of > + * various arbitrary scrubbing functionalities into a unified set of > + * functions. > + * > + * Copyright (c) 2024 HiSilicon Limited. > + */ > + > +#include <linux/edac.h> > + > +enum edac_scrub_attributes { > + SCRUB_ADDRESS, > + SCRUB_SIZE, > + SCRUB_ENABLE_BACKGROUND, > + SCRUB_MIN_CYCLE_DURATION, > + SCRUB_MAX_CYCLE_DURATION, > + SCRUB_CUR_CYCLE_DURATION, > + SCRUB_MAX_ATTRS > +}; > + > +struct edac_scrub_dev_attr { > + struct device_attribute dev_attr; > + u8 instance; > +}; > + > +struct edac_scrub_context { > + char name[EDAC_FEAT_NAME_LEN]; Ok, here you're using EDAC_FEAT_NAME_LEN. Please move its definition from patch 1 to this patch. > + struct edac_scrub_dev_attr scrub_dev_attr[SCRUB_MAX_ATTRS]; > + struct attribute *scrub_attrs[SCRUB_MAX_ATTRS + 1]; > + struct attribute_group group; > +}; > + > +#define TO_SCRUB_DEV_ATTR(_dev_attr) \ > + container_of(_dev_attr, struct edac_scrub_dev_attr, dev_attr) > + > +#define EDAC_SCRUB_ATTR_SHOW(attrib, cb, type, format) \ > +static ssize_t attrib##_show(struct device *ras_feat_dev, \ > + struct device_attribute *attr, char *buf) \ > +{ \ > + u8 inst = TO_SCRUB_DEV_ATTR(attr)->instance; \ > + struct edac_dev_feat_ctx *ctx = dev_get_drvdata(ras_feat_dev); \ > + const struct edac_scrub_ops *ops = ctx->scrub[inst].scrub_ops; \ > + type data; \ > + int ret; \ > + \ > + ret = ops->cb(ras_feat_dev->parent, ctx->scrub[inst].private, &data); \ > + if (ret) \ > + return ret; \ > + \ > + return sysfs_emit(buf, format, data); \ > +} > + > +EDAC_SCRUB_ATTR_SHOW(addr, read_addr, u64, "0x%llx\n") > +EDAC_SCRUB_ATTR_SHOW(size, read_size, u64, "0x%llx\n") > +EDAC_SCRUB_ATTR_SHOW(enable_background, get_enabled_bg, bool, "%u\n") > +EDAC_SCRUB_ATTR_SHOW(min_cycle_duration, get_min_cycle, u32, "%u\n") > +EDAC_SCRUB_ATTR_SHOW(max_cycle_duration, get_max_cycle, u32, "%u\n") > +EDAC_SCRUB_ATTR_SHOW(current_cycle_duration, get_cycle_duration, u32, "%u\n") > + > +#define EDAC_SCRUB_ATTR_STORE(attrib, cb, type, conv_func) \ > +static ssize_t attrib##_store(struct device *ras_feat_dev, \ > + struct device_attribute *attr, \ > + const char *buf, size_t len) \ > +{ \ > + u8 inst = TO_SCRUB_DEV_ATTR(attr)->instance; \ > + struct edac_dev_feat_ctx *ctx = dev_get_drvdata(ras_feat_dev); \ > + const struct edac_scrub_ops *ops = ctx->scrub[inst].scrub_ops; \ > + type data; \ > + int ret; \ > + \ > + ret = conv_func(buf, 0, &data); \ > + if (ret < 0) \ > + return ret; \ > + \ > + ret = ops->cb(ras_feat_dev->parent, ctx->scrub[inst].private, data); \ > + if (ret) \ > + return ret; \ > + \ > + return len; \ > +} > + > +EDAC_SCRUB_ATTR_STORE(addr, write_addr, u64, kstrtou64) > +EDAC_SCRUB_ATTR_STORE(size, write_size, u64, kstrtou64) > +EDAC_SCRUB_ATTR_STORE(enable_background, set_enabled_bg, unsigned long, kstrtoul) > +EDAC_SCRUB_ATTR_STORE(current_cycle_duration, set_cycle_duration, unsigned long, kstrtoul) > + > +static umode_t scrub_attr_visible(struct kobject *kobj, struct attribute *a, int attr_id) > +{ > + struct device *ras_feat_dev = kobj_to_dev(kobj); > + struct device_attribute *dev_attr = container_of(a, struct device_attribute, attr); > + u8 inst = TO_SCRUB_DEV_ATTR(dev_attr)->instance; > + struct edac_dev_feat_ctx *ctx = dev_get_drvdata(ras_feat_dev); > + const struct edac_scrub_ops *ops = ctx->scrub[inst].scrub_ops; > + > + switch (attr_id) { > + case SCRUB_ADDRESS: > + if (ops->read_addr) { > + if (ops->write_addr) > + return a->mode; > + else > + return 0444; > + } > + break; > + case SCRUB_SIZE: > + if (ops->read_size) { > + if (ops->write_size) > + return a->mode; > + else > + return 0444; > + } > + break; > + case SCRUB_ENABLE_BACKGROUND: > + if (ops->get_enabled_bg) { > + if (ops->set_enabled_bg) > + return a->mode; > + else > + return 0444; > + } > + break; > + case SCRUB_MIN_CYCLE_DURATION: > + if (ops->get_min_cycle) > + return a->mode; > + break; > + case SCRUB_MAX_CYCLE_DURATION: > + if (ops->get_max_cycle) > + return a->mode; > + break; > + case SCRUB_CUR_CYCLE_DURATION: > + if (ops->get_cycle_duration) { > + if (ops->set_cycle_duration) > + return a->mode; > + else > + return 0444; > + } > + break; > + default: > + break; > + } > + > + return 0; > +} > + > +#define EDAC_SCRUB_ATTR_RO(_name, _instance) \ > + ((struct edac_scrub_dev_attr) { .dev_attr = __ATTR_RO(_name), \ > + .instance = _instance }) > + > +#define EDAC_SCRUB_ATTR_WO(_name, _instance) \ > + ((struct edac_scrub_dev_attr) { .dev_attr = __ATTR_WO(_name), \ > + .instance = _instance }) > + > +#define EDAC_SCRUB_ATTR_RW(_name, _instance) \ > + ((struct edac_scrub_dev_attr) { .dev_attr = __ATTR_RW(_name), \ > + .instance = _instance }) > + > +static int scrub_create_desc(struct device *scrub_dev, > + const struct attribute_group **attr_groups, u8 instance) > +{ > + struct edac_scrub_context *scrub_ctx; > + struct attribute_group *group; > + int i; > + struct edac_scrub_dev_attr dev_attr[] = { > + [SCRUB_ADDRESS] = EDAC_SCRUB_ATTR_RW(addr, instance), > + [SCRUB_SIZE] = EDAC_SCRUB_ATTR_RW(size, instance), > + [SCRUB_ENABLE_BACKGROUND] = EDAC_SCRUB_ATTR_RW(enable_background, instance), > + [SCRUB_MIN_CYCLE_DURATION] = EDAC_SCRUB_ATTR_RO(min_cycle_duration, instance), > + [SCRUB_MAX_CYCLE_DURATION] = EDAC_SCRUB_ATTR_RO(max_cycle_duration, instance), > + [SCRUB_CUR_CYCLE_DURATION] = EDAC_SCRUB_ATTR_RW(current_cycle_duration, instance) > + }; > + > + scrub_ctx = devm_kzalloc(scrub_dev, sizeof(*scrub_ctx), GFP_KERNEL); > + if (!scrub_ctx) > + return -ENOMEM; > + > + group = &scrub_ctx->group; > + for (i = 0; i < SCRUB_MAX_ATTRS; i++) { > + memcpy(&scrub_ctx->scrub_dev_attr[i], &dev_attr[i], sizeof(dev_attr[i])); > + scrub_ctx->scrub_attrs[i] = &scrub_ctx->scrub_dev_attr[i].dev_attr.attr; > + } > + sprintf(scrub_ctx->name, "%s%d", "scrub", instance); > + group->name = scrub_ctx->name; > + group->attrs = scrub_ctx->scrub_attrs; > + group->is_visible = scrub_attr_visible; > + > + attr_groups[0] = group; > + > + return 0; > +} > + > +/** > + * edac_scrub_get_desc - get EDAC scrub descriptors > + * @scrub_dev: client device, with scrub support > + * @attr_groups: pointer to attribute group container > + * @instance: device's scrub instance number. > + * > + * Return: > + * * %0 - Success. > + * * %-EINVAL - Invalid parameters passed. > + * * %-ENOMEM - Dynamic memory allocation failed. > + */ > +int edac_scrub_get_desc(struct device *scrub_dev, > + const struct attribute_group **attr_groups, u8 instance) > +{ > + if (!scrub_dev || !attr_groups) > + return -EINVAL; > + > + return scrub_create_desc(scrub_dev, attr_groups, instance); > +} > diff --git a/include/linux/edac.h b/include/linux/edac.h > index 521b17113d4d..ace8b10bb028 100644 > --- a/include/linux/edac.h > +++ b/include/linux/edac.h > @@ -666,11 +666,43 @@ static inline struct dimm_info *edac_get_dimm(struct mem_ctl_info *mci, > > /* RAS feature type */ > enum edac_dev_feat { > + RAS_FEAT_SCRUB, > RAS_FEAT_MAX > }; > > +/** > + * struct edac_scrub_ops - scrub device operations (all elements optional) > + * @read_addr: read base address of scrubbing range. > + * @read_size: read offset of scrubbing range. > + * @write_addr: set base address of the scrubbing range. > + * @write_size: set offset of the scrubbing range. > + * @get_enabled_bg: check if currently performing background scrub. > + * @set_enabled_bg: start or stop a bg-scrub. > + * @get_min_cycle: get minimum supported scrub cycle duration in seconds. > + * @get_max_cycle: get maximum supported scrub cycle duration in seconds. > + * @get_cycle_duration: get current scrub cycle duration in seconds. > + * @set_cycle_duration: set current scrub cycle duration in seconds. > + */ > +struct edac_scrub_ops { > + int (*read_addr)(struct device *dev, void *drv_data, u64 *base); > + int (*read_size)(struct device *dev, void *drv_data, u64 *size); > + int (*write_addr)(struct device *dev, void *drv_data, u64 base); > + int (*write_size)(struct device *dev, void *drv_data, u64 size); > + int (*get_enabled_bg)(struct device *dev, void *drv_data, bool *enable); > + int (*set_enabled_bg)(struct device *dev, void *drv_data, bool enable); > + int (*get_min_cycle)(struct device *dev, void *drv_data, u32 *min); > + int (*get_max_cycle)(struct device *dev, void *drv_data, u32 *max); > + int (*get_cycle_duration)(struct device *dev, void *drv_data, u32 *cycle); > + int (*set_cycle_duration)(struct device *dev, void *drv_data, u32 cycle); > +}; > + > +int edac_scrub_get_desc(struct device *scrub_dev, > + const struct attribute_group **attr_groups, > + u8 instance); > + > /* EDAC device feature information structure */ > struct edac_dev_data { > + const struct edac_scrub_ops *scrub_ops; > u8 instance; > void *private; > }; > @@ -678,11 +710,13 @@ struct edac_dev_data { > struct edac_dev_feat_ctx { > struct device dev; > void *private; > + struct edac_dev_data *scrub; > }; > > struct edac_dev_feature { > enum edac_dev_feat ft_type; > u8 instance; > + const struct edac_scrub_ops *scrub_ops; > void *ctx; > }; > Thanks, Mauro