new file mode 100644
@@ -0,0 +1,74 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===================
+EDAC Scrub control
+===================
+
+Copyright (c) 2024 HiSilicon Limited.
+
+:Author: Shiju Jose <shiju.jose@huawei.com>
+:License: The GNU Free Documentation License, Version 1.2
+ (dual licensed under the GPL v2)
+:Original Reviewers:
+
+- Written for: 6.12
+- Updated for:
+
+Introduction
+------------
+The edac scrub driver provides interfaces for controlling the
+memory scrubbers in the system. The scrub device drivers in the
+system register with the edac scrub. The driver exposes the
+scrub controls to the user in the sysfs.
+
+The File System
+---------------
+
+The control attributes of the registered scrubbers could be
+accessed in the /sys/bus/edac/devices/<dev-name>/scrub/
+
+sysfs
+-----
+
+Sysfs files are documented in
+`Documentation/ABI/testing/sysfs-edac-scrub-control`.
+
+Example
+-------
+
+The usage takes the form shown in this example::
+
+1. CXL memory device patrol scrubber
+1.1 device based
+root@localhost:~# cat /sys/bus/edac/devices/cxl_mem0/scrub/min_cycle_duration
+3600
+root@localhost:~# cat /sys/bus/edac/devices/cxl_mem0/scrub/max_cycle_duration
+918000
+root@localhost:~# cat /sys/bus/edac/devices/cxl_mem0/scrub/current_cycle_duration
+43200
+root@localhost:~# echo 54000 > /sys/bus/edac/devices/cxl_mem0/scrub/current_cycle_duration
+root@localhost:~# cat /sys/bus/edac/devices/cxl_mem0/scrub/current_cycle_duration
+54000
+root@localhost:~# echo 1 > /sys/bus/edac/devices/cxl_mem0/scrub/enable_background
+root@localhost:~# cat /sys/bus/edac/devices/cxl_mem0/scrub/enable_background
+1
+root@localhost:~# echo 0 > /sys/bus/edac/devices/cxl_mem0/scrub/enable_background
+root@localhost:~# cat /sys/bus/edac/devices/cxl_mem0/scrub/enable_background
+0
+
+1.2. region based
+root@localhost:~# cat /sys/bus/edac/devices/cxl_region0/scrub/min_cycle_duration
+3600
+root@localhost:~# cat /sys/bus/edac/devices/cxl_region0/scrub/max_cycle_duration
+918000
+root@localhost:~# cat /sys/bus/edac/devices/cxl_region0/scrub/current_cycle_duration
+43200
+root@localhost:~# echo 54000 > /sys/bus/edac/devices/cxl_region0/scrub/current_cycle_duration
+root@localhost:~# cat /sys/bus/edac/devices/cxl_region0/scrub/current_cycle_duration
+54000
+root@localhost:~# echo 1 > /sys/bus/edac/devices/cxl_region0/scrub/enable_background
+root@localhost:~# cat /sys/bus/edac/devices/cxl_region0/scrub/enable_background
+1
+root@localhost:~# echo 0 > /sys/bus/edac/devices/cxl_region0/scrub/enable_background
+root@localhost:~# cat /sys/bus/edac/devices/cxl_region0/scrub/enable_background
+0
@@ -145,4 +145,22 @@ config CXL_REGION_INVALIDATION_TEST
If unsure, or if this kernel is meant for production environments,
say N.
+config CXL_RAS_FEAT
+ bool "CXL: Memory RAS features"
+ depends on CXL_PCI
+ depends on CXL_MEM
+ depends on EDAC
+ help
+ The CXL memory RAS feature control is optional allows host to control
+ the RAS feature's configurations of CXL Type 3 devices.
+
+ Registers with the EDAC device subsystem to expose control attributes
+ of CXL memory device's RAS features to the user.
+ Provides interface functions to support configuring the CXL memory
+ device's RAS features.
+
+ Say 'y/n' to enable/disable CXL.mem device'ss RAS feature's control.
+ See section 8.2.9.9.11 of CXL 3.1 specification for the detailed
+ information of CXL memory device features.
+
endif
@@ -16,3 +16,4 @@ cxl_core-y += pmu.o
cxl_core-y += cdat.o
cxl_core-$(CONFIG_TRACING) += trace.o
cxl_core-$(CONFIG_CXL_REGION) += region.o
+cxl_core-$(CONFIG_CXL_RAS_FEAT) += memfeature.o
new file mode 100644
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * CXL memory RAS feature driver.
+ *
+ * Copyright (c) 2024 HiSilicon Limited.
+ *
+ * - Supports functions to configure RAS features of the
+ * CXL memory devices.
+ * - Registers with the EDAC device subsystem driver to expose
+ * the feature's sysfs attributes to the user for configuring
+ * CXL memory RAS feature.
+ */
+
+#define pr_fmt(fmt) "CXL MEM FEAT: " fmt
+
+#include <cxlmem.h>
+#include <linux/cleanup.h>
+#include <linux/limits.h>
+#include <cxl.h>
+#include <linux/edac.h>
+
+#define CXL_DEV_NUM_RAS_FEATURES 1
+#define CXL_DEV_HOUR_IN_SECS 3600
+
+#define CXL_SCRUB_NAME_LEN 128
+
+/* CXL memory patrol scrub control definitions */
+static const uuid_t cxl_patrol_scrub_uuid =
+ UUID_INIT(0x96dad7d6, 0xfde8, 0x482b, 0xa7, 0x33, 0x75, 0x77, 0x4e, \
+ 0x06, 0xdb, 0x8a);
+
+/* CXL memory patrol scrub control functions */
+struct cxl_patrol_scrub_context {
+ u16 get_feat_size;
+ u16 set_feat_size;
+ u8 get_version;
+ u8 set_version;
+ u16 set_effects;
+ struct cxl_memdev *cxlmd;
+ struct cxl_region *cxlr;
+};
+
+/**
+ * struct cxl_memdev_ps_params - CXL memory patrol scrub parameter data structure.
+ * @enable: [IN & OUT] enable(1)/disable(0) patrol scrub.
+ * @scrub_cycle_changeable: [OUT] scrub cycle attribute of patrol scrub is changeable.
+ * @scrub_cycle_hrs: [IN] Requested patrol scrub cycle in hours.
+ * [OUT] Current patrol scrub cycle in hours.
+ * @min_scrub_cycle_hrs:[OUT] minimum patrol scrub cycle in hours supported.
+ */
+struct cxl_memdev_ps_params {
+ bool enable;
+ bool scrub_cycle_changeable;
+ u16 scrub_cycle_hrs;
+ u16 min_scrub_cycle_hrs;
+};
+
+enum cxl_scrub_param {
+ CXL_PS_PARAM_ENABLE,
+ CXL_PS_PARAM_SCRUB_CYCLE,
+};
+
+#define CXL_MEMDEV_PS_SCRUB_CYCLE_CHANGE_CAP_MASK BIT(0)
+#define CXL_MEMDEV_PS_SCRUB_CYCLE_REALTIME_REPORT_CAP_MASK BIT(1)
+#define CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK GENMASK(7, 0)
+#define CXL_MEMDEV_PS_MIN_SCRUB_CYCLE_MASK GENMASK(15, 8)
+#define CXL_MEMDEV_PS_FLAG_ENABLED_MASK BIT(0)
+
+struct cxl_memdev_ps_rd_attrs {
+ u8 scrub_cycle_cap;
+ __le16 scrub_cycle_hrs;
+ u8 scrub_flags;
+} __packed;
+
+struct cxl_memdev_ps_wr_attrs {
+ u8 scrub_cycle_hrs;
+ u8 scrub_flags;
+} __packed;
+
+static int cxl_mem_ps_get_attrs(struct cxl_memdev_state *mds,
+ struct cxl_memdev_ps_params *params)
+{
+ size_t rd_data_size = sizeof(struct cxl_memdev_ps_rd_attrs);
+ size_t data_size;
+ struct cxl_memdev_ps_rd_attrs *rd_attrs __free(kfree) =
+ kmalloc(rd_data_size, GFP_KERNEL);
+ if (!rd_attrs)
+ return -ENOMEM;
+
+ data_size = cxl_get_feature(mds, cxl_patrol_scrub_uuid,
+ CXL_GET_FEAT_SEL_CURRENT_VALUE,
+ rd_attrs, rd_data_size);
+ if (!data_size)
+ return -EIO;
+
+ params->scrub_cycle_changeable = FIELD_GET(CXL_MEMDEV_PS_SCRUB_CYCLE_CHANGE_CAP_MASK,
+ rd_attrs->scrub_cycle_cap);
+ params->enable = FIELD_GET(CXL_MEMDEV_PS_FLAG_ENABLED_MASK,
+ rd_attrs->scrub_flags);
+ params->scrub_cycle_hrs = FIELD_GET(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK,
+ rd_attrs->scrub_cycle_hrs);
+ params->min_scrub_cycle_hrs = FIELD_GET(CXL_MEMDEV_PS_MIN_SCRUB_CYCLE_MASK,
+ rd_attrs->scrub_cycle_hrs);
+
+ return 0;
+}
+
+static int cxl_ps_get_attrs(struct device *dev, void *drv_data,
+ struct cxl_memdev_ps_params *params)
+{
+ struct cxl_patrol_scrub_context *cxl_ps_ctx = drv_data;
+ struct cxl_memdev *cxlmd;
+ struct cxl_dev_state *cxlds;
+ struct cxl_memdev_state *mds;
+ u16 min_scrub_cycle = 0;
+ int i, ret;
+
+ if (cxl_ps_ctx->cxlr) {
+ struct cxl_region *cxlr = cxl_ps_ctx->cxlr;
+ struct cxl_region_params *p = &cxlr->params;
+
+ for (i = p->interleave_ways - 1; i >= 0; i--) {
+ struct cxl_endpoint_decoder *cxled = p->targets[i];
+
+ cxlmd = cxled_to_memdev(cxled);
+ cxlds = cxlmd->cxlds;
+ mds = to_cxl_memdev_state(cxlds);
+ ret = cxl_mem_ps_get_attrs(mds, params);
+ if (ret)
+ return ret;
+
+ if (params->min_scrub_cycle_hrs > min_scrub_cycle)
+ min_scrub_cycle = params->min_scrub_cycle_hrs;
+ }
+ params->min_scrub_cycle_hrs = min_scrub_cycle;
+ return 0;
+ }
+ cxlmd = cxl_ps_ctx->cxlmd;
+ cxlds = cxlmd->cxlds;
+ mds = to_cxl_memdev_state(cxlds);
+
+ return cxl_mem_ps_get_attrs(mds, params);
+}
+
+static int cxl_mem_ps_set_attrs(struct device *dev, void *drv_data,
+ struct cxl_memdev_state *mds,
+ struct cxl_memdev_ps_params *params,
+ enum cxl_scrub_param param_type)
+{
+ struct cxl_patrol_scrub_context *cxl_ps_ctx = drv_data;
+ struct cxl_memdev_ps_wr_attrs wr_attrs;
+ struct cxl_memdev_ps_params rd_params;
+ int ret;
+
+ ret = cxl_mem_ps_get_attrs(mds, &rd_params);
+ if (ret) {
+ dev_err(dev, "Get cxlmemdev patrol scrub params failed ret=%d\n",
+ ret);
+ return ret;
+ }
+
+ switch (param_type) {
+ case CXL_PS_PARAM_ENABLE:
+ wr_attrs.scrub_flags = FIELD_PREP(CXL_MEMDEV_PS_FLAG_ENABLED_MASK,
+ params->enable);
+ wr_attrs.scrub_cycle_hrs = FIELD_PREP(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK,
+ rd_params.scrub_cycle_hrs);
+ break;
+ case CXL_PS_PARAM_SCRUB_CYCLE:
+ if (params->scrub_cycle_hrs < rd_params.min_scrub_cycle_hrs) {
+ dev_err(dev, "Invalid CXL patrol scrub cycle(%d) to set\n",
+ params->scrub_cycle_hrs);
+ dev_err(dev, "Minimum supported CXL patrol scrub cycle in hour %d\n",
+ params->min_scrub_cycle_hrs);
+ return -EINVAL;
+ }
+ wr_attrs.scrub_cycle_hrs = FIELD_PREP(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK,
+ params->scrub_cycle_hrs);
+ wr_attrs.scrub_flags = FIELD_PREP(CXL_MEMDEV_PS_FLAG_ENABLED_MASK,
+ rd_params.enable);
+ break;
+ }
+
+ ret = cxl_set_feature(mds, cxl_patrol_scrub_uuid, cxl_ps_ctx->set_version,
+ &wr_attrs, sizeof(wr_attrs),
+ CXL_SET_FEAT_FLAG_DATA_SAVED_ACROSS_RESET);
+ if (ret) {
+ dev_err(dev, "CXL patrol scrub set feature failed ret=%d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int cxl_ps_set_attrs(struct device *dev, void *drv_data,
+ struct cxl_memdev_ps_params *params,
+ enum cxl_scrub_param param_type)
+{
+ struct cxl_patrol_scrub_context *cxl_ps_ctx = drv_data;
+ struct cxl_memdev *cxlmd;
+ struct cxl_dev_state *cxlds;
+ struct cxl_memdev_state *mds;
+ int ret, i;
+
+ if (cxl_ps_ctx->cxlr) {
+ struct cxl_region *cxlr = cxl_ps_ctx->cxlr;
+ struct cxl_region_params *p = &cxlr->params;
+
+ for (i = p->interleave_ways - 1; i >= 0; i--) {
+ struct cxl_endpoint_decoder *cxled = p->targets[i];
+
+ cxlmd = cxled_to_memdev(cxled);
+ cxlds = cxlmd->cxlds;
+ mds = to_cxl_memdev_state(cxlds);
+ ret = cxl_mem_ps_set_attrs(dev, drv_data, mds,
+ params, param_type);
+ if (ret)
+ return ret;
+ }
+ } else {
+ cxlmd = cxl_ps_ctx->cxlmd;
+ cxlds = cxlmd->cxlds;
+ mds = to_cxl_memdev_state(cxlds);
+
+ return cxl_mem_ps_set_attrs(dev, drv_data, mds, params, param_type);
+ }
+
+ return 0;
+}
+
+static int cxl_patrol_scrub_get_enabled_bg(struct device *dev, void *drv_data, bool *enabled)
+{
+ struct cxl_memdev_ps_params params;
+ int ret;
+
+ ret = cxl_ps_get_attrs(dev, drv_data, ¶ms);
+ if (ret)
+ return ret;
+
+ *enabled = params.enable;
+
+ return 0;
+}
+
+static int cxl_patrol_scrub_set_enabled_bg(struct device *dev, void *drv_data, bool enable)
+{
+ struct cxl_memdev_ps_params params = {
+ .enable = enable,
+ };
+
+ return cxl_ps_set_attrs(dev, drv_data, ¶ms, CXL_PS_PARAM_ENABLE);
+}
+
+static int cxl_patrol_scrub_read_min_scrub_cycle(struct device *dev, void *drv_data,
+ u32 *min)
+{
+ struct cxl_memdev_ps_params params;
+ int ret;
+
+ ret = cxl_ps_get_attrs(dev, drv_data, ¶ms);
+ if (ret)
+ return ret;
+ *min = params.min_scrub_cycle_hrs * CXL_DEV_HOUR_IN_SECS;
+
+ return 0;
+}
+
+static int cxl_patrol_scrub_read_max_scrub_cycle(struct device *dev, void *drv_data,
+ u32 *max)
+{
+ *max = U8_MAX * CXL_DEV_HOUR_IN_SECS; /* Max set by register size */
+
+ return 0;
+}
+
+static int cxl_patrol_scrub_read_scrub_cycle(struct device *dev, void *drv_data,
+ u32 *scrub_cycle_secs)
+{
+ struct cxl_memdev_ps_params params;
+ int ret;
+
+ ret = cxl_ps_get_attrs(dev, drv_data, ¶ms);
+ if (ret)
+ return ret;
+
+ *scrub_cycle_secs = params.scrub_cycle_hrs * CXL_DEV_HOUR_IN_SECS;
+
+ return 0;
+}
+
+static int cxl_patrol_scrub_write_scrub_cycle(struct device *dev, void *drv_data,
+ u32 scrub_cycle_secs)
+{
+ struct cxl_memdev_ps_params params = {
+ .scrub_cycle_hrs = scrub_cycle_secs / CXL_DEV_HOUR_IN_SECS,
+ };
+
+ return cxl_ps_set_attrs(dev, drv_data, ¶ms, CXL_PS_PARAM_SCRUB_CYCLE);
+}
+
+static const struct edac_scrub_ops cxl_ps_scrub_ops = {
+ .get_enabled_bg = cxl_patrol_scrub_get_enabled_bg,
+ .set_enabled_bg = cxl_patrol_scrub_set_enabled_bg,
+ .min_cycle_read = cxl_patrol_scrub_read_min_scrub_cycle,
+ .max_cycle_read = cxl_patrol_scrub_read_max_scrub_cycle,
+ .cycle_duration_read = cxl_patrol_scrub_read_scrub_cycle,
+ .cycle_duration_write = cxl_patrol_scrub_write_scrub_cycle,
+};
+
+int cxl_mem_ras_features_init(struct cxl_memdev *cxlmd, struct cxl_region *cxlr)
+{
+ struct edac_dev_feature ras_features[CXL_DEV_NUM_RAS_FEATURES];
+ struct cxl_dev_state *cxlds = cxlmd->cxlds;
+ struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds);
+ struct cxl_patrol_scrub_context *cxl_ps_ctx;
+ struct cxl_mbox_supp_feat_entry feat_entry;
+ char cxl_dev_name[CXL_SCRUB_NAME_LEN];
+ int rc, i, num_ras_features = 0;
+
+ if (cxlr) {
+ struct cxl_region_params *p = &cxlr->params;
+
+ for (i = p->interleave_ways - 1; i >= 0; i--) {
+ struct cxl_endpoint_decoder *cxled = p->targets[i];
+
+ cxlmd = cxled_to_memdev(cxled);
+ memset(&feat_entry, 0, sizeof(feat_entry));
+ rc = cxl_get_supported_feature_entry(mds, &cxl_patrol_scrub_uuid,
+ &feat_entry);
+ if (rc < 0)
+ return rc;
+ if (!(feat_entry.attr_flags & CXL_FEAT_ENTRY_FLAG_CHANGABLE))
+ return -EOPNOTSUPP;
+ }
+ } else {
+ rc = cxl_get_supported_feature_entry(mds, &cxl_patrol_scrub_uuid,
+ &feat_entry);
+ if (rc < 0)
+ return rc;
+
+ if (!(feat_entry.attr_flags & CXL_FEAT_ENTRY_FLAG_CHANGABLE))
+ return -EOPNOTSUPP;
+ }
+
+ cxl_ps_ctx = devm_kzalloc(&cxlmd->dev, sizeof(*cxl_ps_ctx), GFP_KERNEL);
+ if (!cxl_ps_ctx)
+ return -ENOMEM;
+
+ *cxl_ps_ctx = (struct cxl_patrol_scrub_context) {
+ .get_feat_size = feat_entry.get_size,
+ .set_feat_size = feat_entry.set_size,
+ .get_version = feat_entry.get_version,
+ .set_version = feat_entry.set_version,
+ .set_effects = feat_entry.set_effects,
+ };
+ if (cxlr) {
+ snprintf(cxl_dev_name, sizeof(cxl_dev_name),
+ "cxl_region%d", cxlr->id);
+ cxl_ps_ctx->cxlr = cxlr;
+ } else {
+ snprintf(cxl_dev_name, sizeof(cxl_dev_name),
+ "%s_%s", "cxl", dev_name(&cxlmd->dev));
+ cxl_ps_ctx->cxlmd = cxlmd;
+ }
+
+ ras_features[num_ras_features].feat = RAS_FEAT_SCRUB;
+ ras_features[num_ras_features].scrub_ops = &cxl_ps_scrub_ops;
+ ras_features[num_ras_features].scrub_ctx = cxl_ps_ctx;
+ num_ras_features++;
+
+ return edac_dev_register(&cxlmd->dev, cxl_dev_name, NULL,
+ num_ras_features, ras_features);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_mem_ras_features_init, CXL);
@@ -3397,6 +3397,12 @@ static int cxl_region_probe(struct device *dev)
p->res->start, p->res->end, cxlr,
is_system_ram) > 0)
return 0;
+
+ rc = cxl_mem_ras_features_init(NULL, cxlr);
+ if (rc)
+ dev_warn(&cxlr->dev, "CXL ras features init for region_id=%d failed\n",
+ cxlr->id);
+
return devm_cxl_add_dax_region(cxlr);
default:
dev_dbg(&cxlr->dev, "unsupported region mode: %d\n",
@@ -962,6 +962,13 @@ int cxl_trigger_poison_list(struct cxl_memdev *cxlmd);
int cxl_inject_poison(struct cxl_memdev *cxlmd, u64 dpa);
int cxl_clear_poison(struct cxl_memdev *cxlmd, u64 dpa);
+#ifdef CONFIG_CXL_RAS_FEAT
+int cxl_mem_ras_features_init(struct cxl_memdev *cxlmd, struct cxl_region *cxlr);
+#else
+static inline int cxl_mem_ras_features_init(struct cxl_memdev *cxlmd, struct cxl_region *cxlr)
+{ return 0; }
+#endif
+
#ifdef CONFIG_CXL_SUSPEND
void cxl_mem_active_inc(void);
void cxl_mem_active_dec(void);
@@ -117,6 +117,10 @@ static int cxl_mem_probe(struct device *dev)
if (!cxlds->media_ready)
return -EBUSY;
+ rc = cxl_mem_ras_features_init(cxlmd, NULL);
+ if (rc)
+ dev_warn(&cxlmd->dev, "CXL ras features init failed\n");
+
/*
* Someone is trying to reattach this device after it lost its port
* connection (an endpoint port previously registered by this memdev was