| Message ID | 20231114125648.1146-3-shiju.jose@huawei.com |
|---|---|
| State | New |
| Headers | show |
| Series | cxl: Add support for CXL feature commands, CXL device patrol scrub control and DDR5 ECS control features | expand |
On 11/14/23 05:56, shiju.jose@huawei.com wrote: > From: Shiju Jose <shiju.jose@huawei.com> > > CXL spec 3.1 section 8.2.9.9.11.1 describes the 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 scrub input configurations. > > The patrol scrub control allows the requester to specify the number of > hours for 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. > > Signed-off-by: Shiju Jose <shiju.jose@huawei.com> > --- > drivers/cxl/Kconfig | 23 ++ > drivers/cxl/core/Makefile | 1 + > drivers/cxl/core/memscrub.c | 455 ++++++++++++++++++++++++++++++++++++ > drivers/cxl/cxlmem.h | 7 + > drivers/cxl/pci.c | 6 + > 5 files changed, 492 insertions(+) Maybe this patch can be split up? Awfully large. Maybe a patch with support functions and then another with usages? > create mode 100644 drivers/cxl/core/memscrub.c > > diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig > index 8ea1d340e438..45ee6d57d899 100644 > --- a/drivers/cxl/Kconfig > +++ b/drivers/cxl/Kconfig > @@ -154,4 +154,27 @@ config CXL_PMU > monitoring units and provide standard perf based interfaces. > > If unsure say 'm'. > + > +config CXL_SCRUB > + tristate "CXL: Memory scrub feature" > + depends on CXL_PCI > + depends on CXL_MEM > + depends on SCRUB > + help > + The CXL memory scrub control is an optional feature allows host to > + control the scrub configurations of CXL Type 3 devices, which > + support patrol scrub and/or DDR5 ECS(Error Check Scrub). > + > + Register with the scrub configure driver to provide sysfs interfaces > + for configuring the CXL device memory patrol and DDR5 ECS scrubs. > + Provides the interface functions support configuring the CXL memory > + device patrol and ECS scrubs. > + > + Say 'y/m' to enable the CXL memory scrub driver that will attach to > + CXL.mem devices for memory scrub control feature. See sections > + 8.2.9.9.11.1 and 8.2.9.9.11.2 in the CXL 3.1 specification for a > + detailed description of CXL memory scrub control features. > + > + If unsure say 'm'. > + > endif > diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile > index 1f66b5d4d935..99e3202f868f 100644 > --- a/drivers/cxl/core/Makefile > +++ b/drivers/cxl/core/Makefile > @@ -15,3 +15,4 @@ cxl_core-y += hdm.o > cxl_core-y += pmu.o > cxl_core-$(CONFIG_TRACING) += trace.o > cxl_core-$(CONFIG_CXL_REGION) += region.o > +cxl_core-$(CONFIG_CXL_SCRUB) += memscrub.o > diff --git a/drivers/cxl/core/memscrub.c b/drivers/cxl/core/memscrub.c > new file mode 100644 > index 000000000000..ec67ffc81363 > --- /dev/null > +++ b/drivers/cxl/core/memscrub.c > @@ -0,0 +1,455 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * cxl_memscrub.c - CXL memory scrub driver > + * > + * Copyright (c) 2023 HiSilicon Limited. > + * > + * - Provides functions to configure patrol scrub > + * feature of the CXL memory devices. > + * - Registers with the scrub driver for the > + * memory patrol scrub feature. > + */ > + > +#define pr_fmt(fmt) "CXL_MEM_SCRUB: " fmt > + > +#include <cxlmem.h> > +#include <memory/memory-scrub.h> > + > +/* CXL memory scrub feature common definitions */ > +#define CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH 128 > +#define CXL_MEMDEV_MAX_NAME_LENGTH 128 > + > +static int cxl_mem_get_supported_feature_entry(struct cxl_memdev *cxlmd, const uuid_t *feat_uuid, > + struct cxl_mbox_supp_feat_entry *feat_entry_out) > +{ > + int nentries; /* number of supported feature entries in output payload */ > + int feat_index, count; > + bool is_support_feature = false; > + struct cxl_mbox_get_supp_feats_in pi; > + struct cxl_mbox_supp_feat_entry *feat_entry; > + struct cxl_mbox_get_supp_feats_out *feats_out; > + struct cxl_dev_state *cxlds = cxlmd->cxlds; > + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); > + > + feat_index = 0; > + do { > + pi.count = sizeof(struct cxl_mbox_get_supp_feats_out) + > + sizeof(struct cxl_mbox_supp_feat_entry); > + pi.start_index = feat_index; > + nentries = 0; Is this needed since you init it to feats_out->entries a few lines below > + feats_out = cxl_get_supported_features(mds, &pi); > + if (PTR_ERR_OR_ZERO(feats_out)) > + return PTR_ERR_OR_ZERO(feats_out); > + nentries = feats_out->entries; > + if (!nentries) { > + kvfree(feats_out); > + break; > + } > + /* Check CXL memdev supports the feature */ > + feat_entry = (void *)feats_out->feat_entries; > + for (count = 0; count < nentries; count++, feat_entry++) { > + if (uuid_equal(&feat_entry->uuid, feat_uuid)) { > + is_support_feature = true; > + memcpy(feat_entry_out, feat_entry, sizeof(*feat_entry_out)); > + break; > + } > + } > + kvfree(feats_out); > + if (is_support_feature) > + break; > + feat_index += nentries; > + } while (nentries); > + > + if (!is_support_feature) > + return -ENOTSUPP; > + > + return 0; > +} > + > +/* CXL memory patrol scrub control definitions */ > +#define CXL_MEMDEV_PS_GET_FEAT_VERSION 0x01 > +#define CXL_MEMDEV_PS_SET_FEAT_VERSION 0x01 > + > +#define CXL_PATROL_SCRUB "cxl_patrol_scrub" > + > +/* The default number of regions for CXL memory device patrol scrubber > + * Patrol scrub is a feature where the device controller scrubs the > + * memory at a regular interval accroding to the CXL specification. > + * Hence the number of memory regions to scrub assosiated to the patrol > + * scrub is 1. > + */ > +#define CXL_MEMDEV_PATROL_SCRUB_NUM_REGIONS 1 > + > +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 { > + struct device *dev; > + u16 get_feat_size; > + u16 set_feat_size; > + bool scrub_cycle_changable; > +}; > + > +/** > + * struct cxl_memdev_ps_params - CXL memory patrol scrub parameter data structure. > + * @enable: [IN] enable(1)/disable(0) patrol scrub. > + * @scrub_cycle_changable: [OUT] scrub cycle attribute of patrol scrub is changeable. > + * @speed: [IN] Requested patrol scrub cycle in hours. > + * [OUT] Current patrol scrub cycle in hours. > + * @min_speed:[OUT] minimum patrol scrub cycle, in hours, supported. > + * @speed_avail:[OUT] Supported patrol scrub cycle in hours. > + */ > +struct cxl_memdev_ps_params { > + bool enable; > + bool scrub_cycle_changable; > + u16 speed; > + u16 min_speed; > + char speed_avail[CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH]; > +}; > + > +enum { > + CXL_MEMDEV_PS_PARAM_ENABLE = 0, > + CXL_MEMDEV_PS_PARAM_SPEED, > +}; > + > +#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_feat_read_attrbs { > + u8 scrub_cycle_cap; > + __le16 scrub_cycle; > + u8 scrub_flags; > +} __packed; > + > +struct cxl_memdev_ps_set_feat_pi { > + struct cxl_mbox_set_feat_in pi; > + u8 scrub_cycle_hr; > + u8 scrub_flags; > +} __packed; > + > +static int cxl_mem_ps_get_attrbs(struct device *dev, > + struct cxl_memdev_ps_params *params) > +{ > + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); > + struct cxl_dev_state *cxlds = cxlmd->cxlds; > + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); > + struct cxl_mbox_get_feat_in pi = { > + .uuid = cxl_patrol_scrub_uuid, > + .offset = 0, > + .count = sizeof(struct cxl_memdev_ps_feat_read_attrbs), > + .selection = CXL_GET_FEAT_CURRENT_VALUE, > + }; > + struct cxl_memdev_ps_feat_read_attrbs *rd_attrbs; > + > + if (!mds) > + return -EFAULT; > + > + rd_attrbs = cxl_get_feature(mds, &pi); > + if (PTR_ERR_OR_ZERO(rd_attrbs)) { > + params->enable = 0; > + params->speed = 0; > + snprintf(params->speed_avail, CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH, > + "Unavailable"); > + return PTR_ERR_OR_ZERO(rd_attrbs); > + } > + params->scrub_cycle_changable = FIELD_GET(CXL_MEMDEV_PS_SCRUB_CYCLE_CHANGE_CAP_MASK, > + rd_attrbs->scrub_cycle_cap); > + params->enable = FIELD_GET(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, > + rd_attrbs->scrub_flags); > + params->speed = FIELD_GET(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, > + rd_attrbs->scrub_cycle); > + params->min_speed = FIELD_GET(CXL_MEMDEV_PS_MIN_SCRUB_CYCLE_MASK, > + rd_attrbs->scrub_cycle); > + snprintf(params->speed_avail, CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH, > + "Minimum scrub cycle = %d hour", params->min_speed); > + kvfree(rd_attrbs); > + > + return 0; > +} > + > +static int cxl_mem_ps_set_attrbs(struct device *dev, > + struct cxl_memdev_ps_params *params, u8 param_type) > +{ > + int ret; > + struct cxl_memdev_ps_params rd_params; > + struct cxl_memdev_ps_set_feat_pi set_pi = { > + .pi.uuid = cxl_patrol_scrub_uuid, > + .pi.flags = CXL_SET_FEAT_FLAG_MOD_VALUE_SAVED_ACROSS_RESET | > + CXL_SET_FEAT_FLAG_ACTION_FULL_DATA_TRANSFER, > + .pi.offset = 0, > + .pi.version = CXL_MEMDEV_PS_SET_FEAT_VERSION, > + }; > + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); > + struct cxl_dev_state *cxlds = cxlmd->cxlds; > + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); > + > + if (!mds) > + return -EFAULT; > + > + ret = 0; Why set to 0 and then overwrite it in the next line? > + ret = cxl_mem_ps_get_attrbs(dev, &rd_params); > + if (ret) { > + dev_err(dev, "Get cxlmemdev patrol scrub params fail ret=%d\n", > + ret); > + return ret; > + } > + > + if (param_type == CXL_MEMDEV_PS_PARAM_ENABLE) { > + set_pi.scrub_flags = FIELD_PREP(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, > + params->enable); > + set_pi.scrub_cycle_hr = FIELD_PREP(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, > + rd_params.speed); > + } else if (param_type == CXL_MEMDEV_PS_PARAM_SPEED) { > + if (params->speed < rd_params.min_speed) { > + dev_err(dev, "Invalid CXL patrol scrub cycle(%d) to set\n", > + params->speed); > + dev_err(dev, "Minimum supported CXL patrol scrub cycle in hour %d\n", > + params->min_speed); > + return -EINVAL; > + } > + set_pi.scrub_cycle_hr = FIELD_PREP(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, > + params->speed); > + set_pi.scrub_flags = FIELD_PREP(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, > + rd_params.enable); > + } else { > + dev_err(dev, "Invalid CXL patrol scrub parameter to set\n"); > + return -EINVAL; > + } > + > + ret = 0; unnecessary init? > + ret = cxl_set_feature(mds, &set_pi, sizeof(set_pi)); > + if (ret) { > + dev_err(dev, "CXL patrol scrub set feature fail ret=%d\n", > + ret); > + return ret; > + } > + > + /* Verify attribute set successfully */ > + if (param_type == CXL_MEMDEV_PS_PARAM_SPEED) { > + ret = cxl_mem_ps_get_attrbs(dev, &rd_params); > + if (ret) { > + dev_err(dev, "Get cxlmemdev patrol scrub params fail ret=%d\n", ret); > + return ret; > + } > + if (rd_params.speed != params->speed) > + return -EFAULT; > + } > + > + return 0; > +} > + > +static int cxl_mem_ps_enable_write(struct device *dev, long val) > +{ > + int ret; > + struct cxl_memdev_ps_params params; > + > + params.enable = val; > + ret = cxl_mem_ps_set_attrbs(dev, ¶ms, CXL_MEMDEV_PS_PARAM_ENABLE); > + if (ret) { > + dev_err(dev, "CXL patrol scrub enable fail, enable=%d ret=%d\n", > + params.enable, ret); > + return ret; > + } > + > + return 0; > +} > + > +static int cxl_mem_ps_speed_read(struct device *dev, u64 *val) > +{ > + int ret; > + struct cxl_memdev_ps_params params; > + > + ret = cxl_mem_ps_get_attrbs(dev, ¶ms); > + if (ret) { > + dev_err(dev, "Get CXL patrol scrub params fail ret=%d\n", > + ret); > + return ret; > + } > + *val = params.speed; > + > + return 0; > +} > + > +static int cxl_mem_ps_speed_write(struct device *dev, long val) > +{ > + int ret; > + struct cxl_memdev_ps_params params; > + > + params.speed = val; > + ret = cxl_mem_ps_set_attrbs(dev, ¶ms, CXL_MEMDEV_PS_PARAM_SPEED); > + if (ret) { > + dev_err(dev, "Set CXL patrol scrub params for speed fail ret=%d\n", > + ret); > + return ret; > + } > + > + return 0; > +} > + > +static int cxl_mem_ps_speed_available_read(struct device *dev, char *buf) > +{ > + int ret; > + struct cxl_memdev_ps_params params; > + > + ret = cxl_mem_ps_get_attrbs(dev, ¶ms); > + if (ret) { > + dev_err(dev, "Get CXL patrol scrub params fail ret=%d\n", > + ret); > + return ret; > + } > + > + sprintf(buf, "%s\n", params.speed_avail); > + > + return 0; > +} > + > +/** > + * cxl_mem_patrol_scrub_is_visible() - Callback to return attribute visibility > + * @drv_data: Pointer to driver-private data structure passed > + * as argument to devm_scrub_device_register(). > + * @attr: Scrub attribute > + * @region_id: ID of the memory region > + * > + * Returns: 0 on success, an error otherwise > + */ > +umode_t cxl_mem_patrol_scrub_is_visible(const void *drv_data, u32 attr, int region_id) > +{ > + const struct cxl_patrol_scrub_context *cxl_ps_ctx = drv_data; > + > + if (attr == scrub_speed_available || > + attr == scrub_speed) { > + if (!cxl_ps_ctx->scrub_cycle_changable) > + return 0; > + } > + > + switch (attr) { > + case scrub_speed_available: > + return 0444; > + case scrub_enable: > + return 0200; > + case scrub_speed: > + return 0644; > + default: > + return 0; > + } > +} > + > +/** > + * cxl_mem_patrol_scrub_read() - Read callback for data attributes > + * @dev: Pointer to scrub device > + * @attr: Scrub attribute > + * @region_id: ID of the memory region > + * @val: Pointer to the returned data > + * > + * Returns: 0 on success, an error otherwise > + */ > +int cxl_mem_patrol_scrub_read(struct device *dev, u32 attr, int region_id, u64 *val) > +{ > + > + switch (attr) { > + case scrub_speed: > + return cxl_mem_ps_speed_read(dev->parent, val); > + default: > + return -ENOTSUPP; > + } > +} > + > +/** > + * cxl_mem_patrol_scrub_write() - Write callback for data attributes > + * @dev: Pointer to scrub device > + * @attr: Scrub attribute > + * @region_id: ID of the memory region > + * @val: Value to write > + * > + * Returns: 0 on success, an error otherwise > + */ > +int cxl_mem_patrol_scrub_write(struct device *dev, u32 attr, int region_id, u64 val) > +{ > + switch (attr) { > + case scrub_enable: > + return cxl_mem_ps_enable_write(dev->parent, val); > + case scrub_speed: > + return cxl_mem_ps_speed_write(dev->parent, val); > + default: > + return -ENOTSUPP; > + } > +} > + > +/** > + * cxl_mem_patrol_scrub_read_strings() - Read callback for string attributes > + * @dev: Pointer to scrub device > + * @attr: Scrub attribute > + * @region_id: ID of the memory region > + * @buf: Pointer to the buffer for copying returned string > + * > + * Returns: 0 on success, an error otherwise > + */ > +int cxl_mem_patrol_scrub_read_strings(struct device *dev, u32 attr, int region_id, > + char *buf) > +{ > + switch (attr) { > + case scrub_speed_available: > + return cxl_mem_ps_speed_available_read(dev->parent, buf); > + default: > + return -ENOTSUPP; > + } > +} > + > +static const struct scrub_ops cxl_ps_scrub_ops = { > + .is_visible = cxl_mem_patrol_scrub_is_visible, > + .read = cxl_mem_patrol_scrub_read, > + .write = cxl_mem_patrol_scrub_write, > + .read_string = cxl_mem_patrol_scrub_read_strings, > +}; > + > +int cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd) > +{ > + int ret = 0; > + struct device *cxl_scrub_dev; > + struct cxl_memdev_ps_params params; > + struct cxl_mbox_supp_feat_entry feat_entry; > + char scrub_name[CXL_MEMDEV_MAX_NAME_LENGTH]; > + struct cxl_patrol_scrub_context *cxl_ps_ctx; > + > + ret = cxl_mem_get_supported_feature_entry(cxlmd, &cxl_patrol_scrub_uuid, > + &feat_entry); > + if (ret < 0) > + goto cxl_ps_init_exit; > + > + if (!(feat_entry.attrb_flags & CXL_FEAT_ENTRY_FLAG_CHANGABLE)) > + goto cxl_ps_init_exit; > + > + cxl_ps_ctx = devm_kzalloc(&cxlmd->dev, sizeof(*cxl_ps_ctx), GFP_KERNEL); > + if (!cxl_ps_ctx) > + goto cxl_ps_init_exit; > + > + cxl_ps_ctx->get_feat_size = feat_entry.get_feat_size; > + cxl_ps_ctx->set_feat_size = feat_entry.set_feat_size; > + ret = cxl_mem_ps_get_attrbs(&cxlmd->dev, ¶ms); > + if (ret) { > + dev_err(&cxlmd->dev, "Get CXL patrol scrub params fail ret=%d\n", > + ret); > + goto cxl_ps_init_exit; > + } > + cxl_ps_ctx->scrub_cycle_changable = params.scrub_cycle_changable; > + > + snprintf(scrub_name, sizeof(scrub_name), "%s_%s", > + CXL_PATROL_SCRUB, dev_name(&cxlmd->dev)); > + cxl_scrub_dev = devm_scrub_device_register(&cxlmd->dev, scrub_name, > + cxl_ps_ctx, &cxl_ps_scrub_ops, > + CXL_MEMDEV_PATROL_SCRUB_NUM_REGIONS); > + if (PTR_ERR_OR_ZERO(cxl_scrub_dev)) { > + ret = PTR_ERR_OR_ZERO(cxl_scrub_dev); > + goto cxl_ps_reg_fail; > + } > + > +cxl_ps_reg_fail: > +cxl_ps_init_exit: > + return ret; > +} > +EXPORT_SYMBOL_NS_GPL(cxl_mem_patrol_scrub_init, CXL); > diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h > index fdac686560d4..1d0fad0dc5ae 100644 > --- a/drivers/cxl/cxlmem.h > +++ b/drivers/cxl/cxlmem.h > @@ -969,6 +969,13 @@ 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); > > +/* cxl memory scrub functions */ > +#ifdef CONFIG_CXL_SCRUB > +int cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd); > +#else > +int cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd) { return -ENOTSUP; } > +#endif > + > #ifdef CONFIG_CXL_SUSPEND > void cxl_mem_active_inc(void); > void cxl_mem_active_dec(void); > diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c > index 0155fb66b580..86bba8794bb4 100644 > --- a/drivers/cxl/pci.c > +++ b/drivers/cxl/pci.c > @@ -881,6 +881,12 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) > if (rc) > return rc; > > + /* > + * Initialize optional CXL scrub features > + */ > + if (cxl_mem_patrol_scrub_init(cxlmd)) > + dev_dbg(&pdev->dev, "cxl_mem_patrol_scrub_init failed\n"); > + > rc = devm_cxl_sanitize_setup_notifier(&pdev->dev, cxlmd); > if (rc) > return rc;
Hi Dave, >-----Original Message----- >From: Dave Jiang <dave.jiang@intel.com> >Sent: 15 November 2023 21:24 >To: Shiju Jose <shiju.jose@huawei.com>; linux-cxl@vger.kernel.org >Cc: Jonathan Cameron <jonathan.cameron@huawei.com>; >Vilas.Sridharan@amd.com; leo.duran@amd.com; Yazen.Ghannam@amd.com; >rientjes@google.com; jiaqiyan@google.com; tony.luck@intel.com; >Jon.Grimm@amd.com; dave.hansen@linux.intel.com; linux- >acpi@vger.kernel.org; linux-mm@kvack.org; linux-kernel@vger.kernel.org; >rafael@kernel.org; lenb@kernel.org; naoya.horiguchi@nec.com; >james.morse@arm.com; david@redhat.com; jthoughton@google.com; >somasundaram.a@hpe.com; erdemaktas@google.com; duenwen@google.com; >mike.malvestuto@intel.com; gthelen@google.com; tanxiaofei ><tanxiaofei@huawei.com>; Zengtao (B) <prime.zeng@hisilicon.com>; >kangkang.shen@futurewei.com; wanghuiqiang <wanghuiqiang@huawei.com>; >Linuxarm <linuxarm@huawei.com> >Subject: Re: [RFC PATCH 2/6] cxl/memscrub: Add CXL device patrol scrub control >feature > > > >On 11/14/23 05:56, shiju.jose@huawei.com wrote: >> From: Shiju Jose <shiju.jose@huawei.com> >> >> CXL spec 3.1 section 8.2.9.9.11.1 describes the 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 scrub input configurations. >> >> The patrol scrub control allows the requester to specify the number of >> hours for 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. >> >> Signed-off-by: Shiju Jose <shiju.jose@huawei.com> >> --- >> drivers/cxl/Kconfig | 23 ++ >> drivers/cxl/core/Makefile | 1 + >> drivers/cxl/core/memscrub.c | 455 >++++++++++++++++++++++++++++++++++++ >> drivers/cxl/cxlmem.h | 7 + >> drivers/cxl/pci.c | 6 + >> 5 files changed, 492 insertions(+) > > >Maybe this patch can be split up? Awfully large. Maybe a patch with support >functions and then another with usages? Sure. I will check this. > >> create mode 100644 drivers/cxl/core/memscrub.c >> >> diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig index >> 8ea1d340e438..45ee6d57d899 100644 >> --- a/drivers/cxl/Kconfig >> +++ b/drivers/cxl/Kconfig >> @@ -154,4 +154,27 @@ config CXL_PMU >> monitoring units and provide standard perf based interfaces. >> >> If unsure say 'm'. >> + >> +config CXL_SCRUB >> + tristate "CXL: Memory scrub feature" >> + depends on CXL_PCI >> + depends on CXL_MEM >> + depends on SCRUB >> + help >> + The CXL memory scrub control is an optional feature allows host to >> + control the scrub configurations of CXL Type 3 devices, which >> + support patrol scrub and/or DDR5 ECS(Error Check Scrub). >> + >> + Register with the scrub configure driver to provide sysfs interfaces >> + for configuring the CXL device memory patrol and DDR5 ECS scrubs. >> + Provides the interface functions support configuring the CXL memory >> + device patrol and ECS scrubs. >> + >> + Say 'y/m' to enable the CXL memory scrub driver that will attach to >> + CXL.mem devices for memory scrub control feature. See sections >> + 8.2.9.9.11.1 and 8.2.9.9.11.2 in the CXL 3.1 specification for a >> + detailed description of CXL memory scrub control features. >> + >> + If unsure say 'm'. >> + >> endif >> diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile >> index 1f66b5d4d935..99e3202f868f 100644 >> --- a/drivers/cxl/core/Makefile >> +++ b/drivers/cxl/core/Makefile >> @@ -15,3 +15,4 @@ cxl_core-y += hdm.o >> cxl_core-y += pmu.o >> cxl_core-$(CONFIG_TRACING) += trace.o >> cxl_core-$(CONFIG_CXL_REGION) += region.o >> +cxl_core-$(CONFIG_CXL_SCRUB) += memscrub.o >> diff --git a/drivers/cxl/core/memscrub.c b/drivers/cxl/core/memscrub.c >> new file mode 100644 index 000000000000..ec67ffc81363 >> --- /dev/null >> +++ b/drivers/cxl/core/memscrub.c >> @@ -0,0 +1,455 @@ >> +// SPDX-License-Identifier: GPL-2.0-or-later >> +/* >> + * cxl_memscrub.c - CXL memory scrub driver >> + * >> + * Copyright (c) 2023 HiSilicon Limited. >> + * >> + * - Provides functions to configure patrol scrub >> + * feature of the CXL memory devices. >> + * - Registers with the scrub driver for the >> + * memory patrol scrub feature. >> + */ >> + >> +#define pr_fmt(fmt) "CXL_MEM_SCRUB: " fmt >> + >> +#include <cxlmem.h> >> +#include <memory/memory-scrub.h> >> + >> +/* CXL memory scrub feature common definitions */ >> +#define CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH 128 >> +#define CXL_MEMDEV_MAX_NAME_LENGTH 128 >> + >> +static int cxl_mem_get_supported_feature_entry(struct cxl_memdev *cxlmd, >const uuid_t *feat_uuid, >> + struct cxl_mbox_supp_feat_entry >*feat_entry_out) { >> + int nentries; /* number of supported feature entries in output payload */ >> + int feat_index, count; >> + bool is_support_feature = false; >> + struct cxl_mbox_get_supp_feats_in pi; >> + struct cxl_mbox_supp_feat_entry *feat_entry; >> + struct cxl_mbox_get_supp_feats_out *feats_out; >> + struct cxl_dev_state *cxlds = cxlmd->cxlds; >> + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); >> + >> + feat_index = 0; >> + do { >> + pi.count = sizeof(struct cxl_mbox_get_supp_feats_out) + >> + sizeof(struct cxl_mbox_supp_feat_entry); >> + pi.start_index = feat_index; >> + nentries = 0; > >Is this needed since you init it to feats_out->entries a few lines below Will remove. > >> + feats_out = cxl_get_supported_features(mds, &pi); >> + if (PTR_ERR_OR_ZERO(feats_out)) >> + return PTR_ERR_OR_ZERO(feats_out); >> + nentries = feats_out->entries; >> + if (!nentries) { >> + kvfree(feats_out); >> + break; >> + } >> + /* Check CXL memdev supports the feature */ >> + feat_entry = (void *)feats_out->feat_entries; >> + for (count = 0; count < nentries; count++, feat_entry++) { >> + if (uuid_equal(&feat_entry->uuid, feat_uuid)) { >> + is_support_feature = true; >> + memcpy(feat_entry_out, feat_entry, >sizeof(*feat_entry_out)); >> + break; >> + } >> + } >> + kvfree(feats_out); >> + if (is_support_feature) >> + break; >> + feat_index += nentries; >> + } while (nentries); >> + >> + if (!is_support_feature) >> + return -ENOTSUPP; >> + >> + return 0; >> +} >> + >> +/* CXL memory patrol scrub control definitions */ >> +#define CXL_MEMDEV_PS_GET_FEAT_VERSION 0x01 >> +#define CXL_MEMDEV_PS_SET_FEAT_VERSION 0x01 >> + >> +#define CXL_PATROL_SCRUB "cxl_patrol_scrub" >> + >> +/* The default number of regions for CXL memory device patrol >> +scrubber >> + * Patrol scrub is a feature where the device controller scrubs the >> + * memory at a regular interval accroding to the CXL specification. >> + * Hence the number of memory regions to scrub assosiated to the >> +patrol >> + * scrub is 1. >> + */ >> +#define CXL_MEMDEV_PATROL_SCRUB_NUM_REGIONS 1 >> + >> +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 { >> + struct device *dev; >> + u16 get_feat_size; >> + u16 set_feat_size; >> + bool scrub_cycle_changable; >> +}; >> + >> +/** >> + * struct cxl_memdev_ps_params - CXL memory patrol scrub parameter data >structure. >> + * @enable: [IN] enable(1)/disable(0) patrol scrub. >> + * @scrub_cycle_changable: [OUT] scrub cycle attribute of patrol scrub is >changeable. >> + * @speed: [IN] Requested patrol scrub cycle in hours. >> + * [OUT] Current patrol scrub cycle in hours. >> + * @min_speed:[OUT] minimum patrol scrub cycle, in hours, supported. >> + * @speed_avail:[OUT] Supported patrol scrub cycle in hours. >> + */ >> +struct cxl_memdev_ps_params { >> + bool enable; >> + bool scrub_cycle_changable; >> + u16 speed; >> + u16 min_speed; >> + char speed_avail[CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH]; >> +}; >> + >> +enum { >> + CXL_MEMDEV_PS_PARAM_ENABLE = 0, >> + CXL_MEMDEV_PS_PARAM_SPEED, >> +}; >> + >> +#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_feat_read_attrbs { >> + u8 scrub_cycle_cap; >> + __le16 scrub_cycle; >> + u8 scrub_flags; >> +} __packed; >> + >> +struct cxl_memdev_ps_set_feat_pi { >> + struct cxl_mbox_set_feat_in pi; >> + u8 scrub_cycle_hr; >> + u8 scrub_flags; >> +} __packed; >> + >> +static int cxl_mem_ps_get_attrbs(struct device *dev, >> + struct cxl_memdev_ps_params *params) { >> + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); >> + struct cxl_dev_state *cxlds = cxlmd->cxlds; >> + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); >> + struct cxl_mbox_get_feat_in pi = { >> + .uuid = cxl_patrol_scrub_uuid, >> + .offset = 0, >> + .count = sizeof(struct cxl_memdev_ps_feat_read_attrbs), >> + .selection = CXL_GET_FEAT_CURRENT_VALUE, >> + }; >> + struct cxl_memdev_ps_feat_read_attrbs *rd_attrbs; >> + >> + if (!mds) >> + return -EFAULT; >> + >> + rd_attrbs = cxl_get_feature(mds, &pi); >> + if (PTR_ERR_OR_ZERO(rd_attrbs)) { >> + params->enable = 0; >> + params->speed = 0; >> + snprintf(params->speed_avail, >CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH, >> + "Unavailable"); >> + return PTR_ERR_OR_ZERO(rd_attrbs); >> + } >> + params->scrub_cycle_changable = >FIELD_GET(CXL_MEMDEV_PS_SCRUB_CYCLE_CHANGE_CAP_MASK, >> + rd_attrbs->scrub_cycle_cap); >> + params->enable = >FIELD_GET(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, >> + rd_attrbs->scrub_flags); >> + params->speed = >FIELD_GET(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, >> + rd_attrbs->scrub_cycle); >> + params->min_speed = >FIELD_GET(CXL_MEMDEV_PS_MIN_SCRUB_CYCLE_MASK, >> + rd_attrbs->scrub_cycle); >> + snprintf(params->speed_avail, >CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH, >> + "Minimum scrub cycle = %d hour", params->min_speed); >> + kvfree(rd_attrbs); >> + >> + return 0; >> +} >> + >> +static int cxl_mem_ps_set_attrbs(struct device *dev, >> + struct cxl_memdev_ps_params *params, u8 >param_type) { >> + int ret; >> + struct cxl_memdev_ps_params rd_params; >> + struct cxl_memdev_ps_set_feat_pi set_pi = { >> + .pi.uuid = cxl_patrol_scrub_uuid, >> + .pi.flags = >CXL_SET_FEAT_FLAG_MOD_VALUE_SAVED_ACROSS_RESET | >> + >CXL_SET_FEAT_FLAG_ACTION_FULL_DATA_TRANSFER, >> + .pi.offset = 0, >> + .pi.version = CXL_MEMDEV_PS_SET_FEAT_VERSION, >> + }; >> + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); >> + struct cxl_dev_state *cxlds = cxlmd->cxlds; >> + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); >> + >> + if (!mds) >> + return -EFAULT; >> + >> + ret = 0; > >Why set to 0 and then overwrite it in the next line? Will remove. > >> + ret = cxl_mem_ps_get_attrbs(dev, &rd_params); >> + if (ret) { >> + dev_err(dev, "Get cxlmemdev patrol scrub params fail >ret=%d\n", >> + ret); >> + return ret; >> + } >> + >> + if (param_type == CXL_MEMDEV_PS_PARAM_ENABLE) { >> + set_pi.scrub_flags = >FIELD_PREP(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, >> + params->enable); >> + set_pi.scrub_cycle_hr = >FIELD_PREP(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, >> + rd_params.speed); >> + } else if (param_type == CXL_MEMDEV_PS_PARAM_SPEED) { >> + if (params->speed < rd_params.min_speed) { >> + dev_err(dev, "Invalid CXL patrol scrub cycle(%d) to >set\n", >> + params->speed); >> + dev_err(dev, "Minimum supported CXL patrol scrub >cycle in hour %d\n", >> + params->min_speed); >> + return -EINVAL; >> + } >> + set_pi.scrub_cycle_hr = >FIELD_PREP(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, >> + params->speed); >> + set_pi.scrub_flags = >FIELD_PREP(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, >> + rd_params.enable); >> + } else { >> + dev_err(dev, "Invalid CXL patrol scrub parameter to set\n"); >> + return -EINVAL; >> + } >> + >> + ret = 0; > >unnecessary init? Ok. Will remove. > >> + ret = cxl_set_feature(mds, &set_pi, sizeof(set_pi)); >> + if (ret) { >> + dev_err(dev, "CXL patrol scrub set feature fail ret=%d\n", >> + ret); >> + return ret; >> + } >> + >> + /* Verify attribute set successfully */ >> + if (param_type == CXL_MEMDEV_PS_PARAM_SPEED) { >> + ret = cxl_mem_ps_get_attrbs(dev, &rd_params); >> + if (ret) { >> + dev_err(dev, "Get cxlmemdev patrol scrub params fail >ret=%d\n", ret); >> + return ret; >> + } >> + if (rd_params.speed != params->speed) >> + return -EFAULT; >> + } >> + >> + return 0; >> +} >> + >> +static int cxl_mem_ps_enable_write(struct device *dev, long val) { >> + int ret; >> + struct cxl_memdev_ps_params params; >> + >> + params.enable = val; >> + ret = cxl_mem_ps_set_attrbs(dev, ¶ms, >CXL_MEMDEV_PS_PARAM_ENABLE); >> + if (ret) { >> + dev_err(dev, "CXL patrol scrub enable fail, enable=%d >ret=%d\n", >> + params.enable, ret); >> + return ret; >> + } >> + >> + return 0; >> +} >> + >> +static int cxl_mem_ps_speed_read(struct device *dev, u64 *val) { >> + int ret; >> + struct cxl_memdev_ps_params params; >> + >> + ret = cxl_mem_ps_get_attrbs(dev, ¶ms); >> + if (ret) { >> + dev_err(dev, "Get CXL patrol scrub params fail ret=%d\n", >> + ret); >> + return ret; >> + } >> + *val = params.speed; >> + >> + return 0; >> +} >> + >> +static int cxl_mem_ps_speed_write(struct device *dev, long val) { >> + int ret; >> + struct cxl_memdev_ps_params params; >> + >> + params.speed = val; >> + ret = cxl_mem_ps_set_attrbs(dev, ¶ms, >CXL_MEMDEV_PS_PARAM_SPEED); >> + if (ret) { >> + dev_err(dev, "Set CXL patrol scrub params for speed fail >ret=%d\n", >> + ret); >> + return ret; >> + } >> + >> + return 0; >> +} >> + >> +static int cxl_mem_ps_speed_available_read(struct device *dev, char >> +*buf) { >> + int ret; >> + struct cxl_memdev_ps_params params; >> + >> + ret = cxl_mem_ps_get_attrbs(dev, ¶ms); >> + if (ret) { >> + dev_err(dev, "Get CXL patrol scrub params fail ret=%d\n", >> + ret); >> + return ret; >> + } >> + >> + sprintf(buf, "%s\n", params.speed_avail); >> + >> + return 0; >> +} >> + >> +/** >> + * cxl_mem_patrol_scrub_is_visible() - Callback to return attribute >> +visibility >> + * @drv_data: Pointer to driver-private data structure passed >> + * as argument to devm_scrub_device_register(). >> + * @attr: Scrub attribute >> + * @region_id: ID of the memory region >> + * >> + * Returns: 0 on success, an error otherwise */ umode_t >> +cxl_mem_patrol_scrub_is_visible(const void *drv_data, u32 attr, int >> +region_id) { >> + const struct cxl_patrol_scrub_context *cxl_ps_ctx = drv_data; >> + >> + if (attr == scrub_speed_available || >> + attr == scrub_speed) { >> + if (!cxl_ps_ctx->scrub_cycle_changable) >> + return 0; >> + } >> + >> + switch (attr) { >> + case scrub_speed_available: >> + return 0444; >> + case scrub_enable: >> + return 0200; >> + case scrub_speed: >> + return 0644; >> + default: >> + return 0; >> + } >> +} >> + >> +/** >> + * cxl_mem_patrol_scrub_read() - Read callback for data attributes >> + * @dev: Pointer to scrub device >> + * @attr: Scrub attribute >> + * @region_id: ID of the memory region >> + * @val: Pointer to the returned data >> + * >> + * Returns: 0 on success, an error otherwise */ int >> +cxl_mem_patrol_scrub_read(struct device *dev, u32 attr, int >> +region_id, u64 *val) { >> + >> + switch (attr) { >> + case scrub_speed: >> + return cxl_mem_ps_speed_read(dev->parent, val); >> + default: >> + return -ENOTSUPP; >> + } >> +} >> + >> +/** >> + * cxl_mem_patrol_scrub_write() - Write callback for data attributes >> + * @dev: Pointer to scrub device >> + * @attr: Scrub attribute >> + * @region_id: ID of the memory region >> + * @val: Value to write >> + * >> + * Returns: 0 on success, an error otherwise */ int >> +cxl_mem_patrol_scrub_write(struct device *dev, u32 attr, int >> +region_id, u64 val) { >> + switch (attr) { >> + case scrub_enable: >> + return cxl_mem_ps_enable_write(dev->parent, val); >> + case scrub_speed: >> + return cxl_mem_ps_speed_write(dev->parent, val); >> + default: >> + return -ENOTSUPP; >> + } >> +} >> + >> +/** >> + * cxl_mem_patrol_scrub_read_strings() - Read callback for string >> +attributes >> + * @dev: Pointer to scrub device >> + * @attr: Scrub attribute >> + * @region_id: ID of the memory region >> + * @buf: Pointer to the buffer for copying returned string >> + * >> + * Returns: 0 on success, an error otherwise */ int >> +cxl_mem_patrol_scrub_read_strings(struct device *dev, u32 attr, int >region_id, >> + char *buf) >> +{ >> + switch (attr) { >> + case scrub_speed_available: >> + return cxl_mem_ps_speed_available_read(dev->parent, buf); >> + default: >> + return -ENOTSUPP; >> + } >> +} >> + >> +static const struct scrub_ops cxl_ps_scrub_ops = { >> + .is_visible = cxl_mem_patrol_scrub_is_visible, >> + .read = cxl_mem_patrol_scrub_read, >> + .write = cxl_mem_patrol_scrub_write, >> + .read_string = cxl_mem_patrol_scrub_read_strings, >> +}; >> + >> +int cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd) { >> + int ret = 0; >> + struct device *cxl_scrub_dev; >> + struct cxl_memdev_ps_params params; >> + struct cxl_mbox_supp_feat_entry feat_entry; >> + char scrub_name[CXL_MEMDEV_MAX_NAME_LENGTH]; >> + struct cxl_patrol_scrub_context *cxl_ps_ctx; >> + >> + ret = cxl_mem_get_supported_feature_entry(cxlmd, >&cxl_patrol_scrub_uuid, >> + &feat_entry); >> + if (ret < 0) >> + goto cxl_ps_init_exit; >> + >> + if (!(feat_entry.attrb_flags & CXL_FEAT_ENTRY_FLAG_CHANGABLE)) >> + goto cxl_ps_init_exit; >> + >> + cxl_ps_ctx = devm_kzalloc(&cxlmd->dev, sizeof(*cxl_ps_ctx), >GFP_KERNEL); >> + if (!cxl_ps_ctx) >> + goto cxl_ps_init_exit; >> + >> + cxl_ps_ctx->get_feat_size = feat_entry.get_feat_size; >> + cxl_ps_ctx->set_feat_size = feat_entry.set_feat_size; >> + ret = cxl_mem_ps_get_attrbs(&cxlmd->dev, ¶ms); >> + if (ret) { >> + dev_err(&cxlmd->dev, "Get CXL patrol scrub params fail >ret=%d\n", >> + ret); >> + goto cxl_ps_init_exit; >> + } >> + cxl_ps_ctx->scrub_cycle_changable = params.scrub_cycle_changable; >> + >> + snprintf(scrub_name, sizeof(scrub_name), "%s_%s", >> + CXL_PATROL_SCRUB, dev_name(&cxlmd->dev)); >> + cxl_scrub_dev = devm_scrub_device_register(&cxlmd->dev, >scrub_name, >> + cxl_ps_ctx, >&cxl_ps_scrub_ops, >> + >CXL_MEMDEV_PATROL_SCRUB_NUM_REGIONS); >> + if (PTR_ERR_OR_ZERO(cxl_scrub_dev)) { >> + ret = PTR_ERR_OR_ZERO(cxl_scrub_dev); >> + goto cxl_ps_reg_fail; >> + } >> + >> +cxl_ps_reg_fail: >> +cxl_ps_init_exit: >> + return ret; >> +} >> +EXPORT_SYMBOL_NS_GPL(cxl_mem_patrol_scrub_init, CXL); >> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h index >> fdac686560d4..1d0fad0dc5ae 100644 >> --- a/drivers/cxl/cxlmem.h >> +++ b/drivers/cxl/cxlmem.h >> @@ -969,6 +969,13 @@ 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); >> >> +/* cxl memory scrub functions */ >> +#ifdef CONFIG_CXL_SCRUB >> +int cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd); #else int >> +cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd) { return >> +-ENOTSUP; } #endif >> + >> #ifdef CONFIG_CXL_SUSPEND >> void cxl_mem_active_inc(void); >> void cxl_mem_active_dec(void); >> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index >> 0155fb66b580..86bba8794bb4 100644 >> --- a/drivers/cxl/pci.c >> +++ b/drivers/cxl/pci.c >> @@ -881,6 +881,12 @@ static int cxl_pci_probe(struct pci_dev *pdev, const >struct pci_device_id *id) >> if (rc) >> return rc; >> >> + /* >> + * Initialize optional CXL scrub features >> + */ >> + if (cxl_mem_patrol_scrub_init(cxlmd)) >> + dev_dbg(&pdev->dev, "cxl_mem_patrol_scrub_init failed\n"); >> + >> rc = devm_cxl_sanitize_setup_notifier(&pdev->dev, cxlmd); >> if (rc) >> return rc; Thanks, Shiju
diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig index 8ea1d340e438..45ee6d57d899 100644 --- a/drivers/cxl/Kconfig +++ b/drivers/cxl/Kconfig @@ -154,4 +154,27 @@ config CXL_PMU monitoring units and provide standard perf based interfaces. If unsure say 'm'. + +config CXL_SCRUB + tristate "CXL: Memory scrub feature" + depends on CXL_PCI + depends on CXL_MEM + depends on SCRUB + help + The CXL memory scrub control is an optional feature allows host to + control the scrub configurations of CXL Type 3 devices, which + support patrol scrub and/or DDR5 ECS(Error Check Scrub). + + Register with the scrub configure driver to provide sysfs interfaces + for configuring the CXL device memory patrol and DDR5 ECS scrubs. + Provides the interface functions support configuring the CXL memory + device patrol and ECS scrubs. + + Say 'y/m' to enable the CXL memory scrub driver that will attach to + CXL.mem devices for memory scrub control feature. See sections + 8.2.9.9.11.1 and 8.2.9.9.11.2 in the CXL 3.1 specification for a + detailed description of CXL memory scrub control features. + + If unsure say 'm'. + endif diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile index 1f66b5d4d935..99e3202f868f 100644 --- a/drivers/cxl/core/Makefile +++ b/drivers/cxl/core/Makefile @@ -15,3 +15,4 @@ cxl_core-y += hdm.o cxl_core-y += pmu.o cxl_core-$(CONFIG_TRACING) += trace.o cxl_core-$(CONFIG_CXL_REGION) += region.o +cxl_core-$(CONFIG_CXL_SCRUB) += memscrub.o diff --git a/drivers/cxl/core/memscrub.c b/drivers/cxl/core/memscrub.c new file mode 100644 index 000000000000..ec67ffc81363 --- /dev/null +++ b/drivers/cxl/core/memscrub.c @@ -0,0 +1,455 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * cxl_memscrub.c - CXL memory scrub driver + * + * Copyright (c) 2023 HiSilicon Limited. + * + * - Provides functions to configure patrol scrub + * feature of the CXL memory devices. + * - Registers with the scrub driver for the + * memory patrol scrub feature. + */ + +#define pr_fmt(fmt) "CXL_MEM_SCRUB: " fmt + +#include <cxlmem.h> +#include <memory/memory-scrub.h> + +/* CXL memory scrub feature common definitions */ +#define CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH 128 +#define CXL_MEMDEV_MAX_NAME_LENGTH 128 + +static int cxl_mem_get_supported_feature_entry(struct cxl_memdev *cxlmd, const uuid_t *feat_uuid, + struct cxl_mbox_supp_feat_entry *feat_entry_out) +{ + int nentries; /* number of supported feature entries in output payload */ + int feat_index, count; + bool is_support_feature = false; + struct cxl_mbox_get_supp_feats_in pi; + struct cxl_mbox_supp_feat_entry *feat_entry; + struct cxl_mbox_get_supp_feats_out *feats_out; + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); + + feat_index = 0; + do { + pi.count = sizeof(struct cxl_mbox_get_supp_feats_out) + + sizeof(struct cxl_mbox_supp_feat_entry); + pi.start_index = feat_index; + nentries = 0; + feats_out = cxl_get_supported_features(mds, &pi); + if (PTR_ERR_OR_ZERO(feats_out)) + return PTR_ERR_OR_ZERO(feats_out); + nentries = feats_out->entries; + if (!nentries) { + kvfree(feats_out); + break; + } + /* Check CXL memdev supports the feature */ + feat_entry = (void *)feats_out->feat_entries; + for (count = 0; count < nentries; count++, feat_entry++) { + if (uuid_equal(&feat_entry->uuid, feat_uuid)) { + is_support_feature = true; + memcpy(feat_entry_out, feat_entry, sizeof(*feat_entry_out)); + break; + } + } + kvfree(feats_out); + if (is_support_feature) + break; + feat_index += nentries; + } while (nentries); + + if (!is_support_feature) + return -ENOTSUPP; + + return 0; +} + +/* CXL memory patrol scrub control definitions */ +#define CXL_MEMDEV_PS_GET_FEAT_VERSION 0x01 +#define CXL_MEMDEV_PS_SET_FEAT_VERSION 0x01 + +#define CXL_PATROL_SCRUB "cxl_patrol_scrub" + +/* The default number of regions for CXL memory device patrol scrubber + * Patrol scrub is a feature where the device controller scrubs the + * memory at a regular interval accroding to the CXL specification. + * Hence the number of memory regions to scrub assosiated to the patrol + * scrub is 1. + */ +#define CXL_MEMDEV_PATROL_SCRUB_NUM_REGIONS 1 + +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 { + struct device *dev; + u16 get_feat_size; + u16 set_feat_size; + bool scrub_cycle_changable; +}; + +/** + * struct cxl_memdev_ps_params - CXL memory patrol scrub parameter data structure. + * @enable: [IN] enable(1)/disable(0) patrol scrub. + * @scrub_cycle_changable: [OUT] scrub cycle attribute of patrol scrub is changeable. + * @speed: [IN] Requested patrol scrub cycle in hours. + * [OUT] Current patrol scrub cycle in hours. + * @min_speed:[OUT] minimum patrol scrub cycle, in hours, supported. + * @speed_avail:[OUT] Supported patrol scrub cycle in hours. + */ +struct cxl_memdev_ps_params { + bool enable; + bool scrub_cycle_changable; + u16 speed; + u16 min_speed; + char speed_avail[CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH]; +}; + +enum { + CXL_MEMDEV_PS_PARAM_ENABLE = 0, + CXL_MEMDEV_PS_PARAM_SPEED, +}; + +#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_feat_read_attrbs { + u8 scrub_cycle_cap; + __le16 scrub_cycle; + u8 scrub_flags; +} __packed; + +struct cxl_memdev_ps_set_feat_pi { + struct cxl_mbox_set_feat_in pi; + u8 scrub_cycle_hr; + u8 scrub_flags; +} __packed; + +static int cxl_mem_ps_get_attrbs(struct device *dev, + struct cxl_memdev_ps_params *params) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); + struct cxl_mbox_get_feat_in pi = { + .uuid = cxl_patrol_scrub_uuid, + .offset = 0, + .count = sizeof(struct cxl_memdev_ps_feat_read_attrbs), + .selection = CXL_GET_FEAT_CURRENT_VALUE, + }; + struct cxl_memdev_ps_feat_read_attrbs *rd_attrbs; + + if (!mds) + return -EFAULT; + + rd_attrbs = cxl_get_feature(mds, &pi); + if (PTR_ERR_OR_ZERO(rd_attrbs)) { + params->enable = 0; + params->speed = 0; + snprintf(params->speed_avail, CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH, + "Unavailable"); + return PTR_ERR_OR_ZERO(rd_attrbs); + } + params->scrub_cycle_changable = FIELD_GET(CXL_MEMDEV_PS_SCRUB_CYCLE_CHANGE_CAP_MASK, + rd_attrbs->scrub_cycle_cap); + params->enable = FIELD_GET(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, + rd_attrbs->scrub_flags); + params->speed = FIELD_GET(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, + rd_attrbs->scrub_cycle); + params->min_speed = FIELD_GET(CXL_MEMDEV_PS_MIN_SCRUB_CYCLE_MASK, + rd_attrbs->scrub_cycle); + snprintf(params->speed_avail, CXL_SCRUB_MAX_ATTRB_RANGE_LENGTH, + "Minimum scrub cycle = %d hour", params->min_speed); + kvfree(rd_attrbs); + + return 0; +} + +static int cxl_mem_ps_set_attrbs(struct device *dev, + struct cxl_memdev_ps_params *params, u8 param_type) +{ + int ret; + struct cxl_memdev_ps_params rd_params; + struct cxl_memdev_ps_set_feat_pi set_pi = { + .pi.uuid = cxl_patrol_scrub_uuid, + .pi.flags = CXL_SET_FEAT_FLAG_MOD_VALUE_SAVED_ACROSS_RESET | + CXL_SET_FEAT_FLAG_ACTION_FULL_DATA_TRANSFER, + .pi.offset = 0, + .pi.version = CXL_MEMDEV_PS_SET_FEAT_VERSION, + }; + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); + + if (!mds) + return -EFAULT; + + ret = 0; + ret = cxl_mem_ps_get_attrbs(dev, &rd_params); + if (ret) { + dev_err(dev, "Get cxlmemdev patrol scrub params fail ret=%d\n", + ret); + return ret; + } + + if (param_type == CXL_MEMDEV_PS_PARAM_ENABLE) { + set_pi.scrub_flags = FIELD_PREP(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, + params->enable); + set_pi.scrub_cycle_hr = FIELD_PREP(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, + rd_params.speed); + } else if (param_type == CXL_MEMDEV_PS_PARAM_SPEED) { + if (params->speed < rd_params.min_speed) { + dev_err(dev, "Invalid CXL patrol scrub cycle(%d) to set\n", + params->speed); + dev_err(dev, "Minimum supported CXL patrol scrub cycle in hour %d\n", + params->min_speed); + return -EINVAL; + } + set_pi.scrub_cycle_hr = FIELD_PREP(CXL_MEMDEV_PS_CUR_SCRUB_CYCLE_MASK, + params->speed); + set_pi.scrub_flags = FIELD_PREP(CXL_MEMDEV_PS_FLAG_ENABLED_MASK, + rd_params.enable); + } else { + dev_err(dev, "Invalid CXL patrol scrub parameter to set\n"); + return -EINVAL; + } + + ret = 0; + ret = cxl_set_feature(mds, &set_pi, sizeof(set_pi)); + if (ret) { + dev_err(dev, "CXL patrol scrub set feature fail ret=%d\n", + ret); + return ret; + } + + /* Verify attribute set successfully */ + if (param_type == CXL_MEMDEV_PS_PARAM_SPEED) { + ret = cxl_mem_ps_get_attrbs(dev, &rd_params); + if (ret) { + dev_err(dev, "Get cxlmemdev patrol scrub params fail ret=%d\n", ret); + return ret; + } + if (rd_params.speed != params->speed) + return -EFAULT; + } + + return 0; +} + +static int cxl_mem_ps_enable_write(struct device *dev, long val) +{ + int ret; + struct cxl_memdev_ps_params params; + + params.enable = val; + ret = cxl_mem_ps_set_attrbs(dev, ¶ms, CXL_MEMDEV_PS_PARAM_ENABLE); + if (ret) { + dev_err(dev, "CXL patrol scrub enable fail, enable=%d ret=%d\n", + params.enable, ret); + return ret; + } + + return 0; +} + +static int cxl_mem_ps_speed_read(struct device *dev, u64 *val) +{ + int ret; + struct cxl_memdev_ps_params params; + + ret = cxl_mem_ps_get_attrbs(dev, ¶ms); + if (ret) { + dev_err(dev, "Get CXL patrol scrub params fail ret=%d\n", + ret); + return ret; + } + *val = params.speed; + + return 0; +} + +static int cxl_mem_ps_speed_write(struct device *dev, long val) +{ + int ret; + struct cxl_memdev_ps_params params; + + params.speed = val; + ret = cxl_mem_ps_set_attrbs(dev, ¶ms, CXL_MEMDEV_PS_PARAM_SPEED); + if (ret) { + dev_err(dev, "Set CXL patrol scrub params for speed fail ret=%d\n", + ret); + return ret; + } + + return 0; +} + +static int cxl_mem_ps_speed_available_read(struct device *dev, char *buf) +{ + int ret; + struct cxl_memdev_ps_params params; + + ret = cxl_mem_ps_get_attrbs(dev, ¶ms); + if (ret) { + dev_err(dev, "Get CXL patrol scrub params fail ret=%d\n", + ret); + return ret; + } + + sprintf(buf, "%s\n", params.speed_avail); + + return 0; +} + +/** + * cxl_mem_patrol_scrub_is_visible() - Callback to return attribute visibility + * @drv_data: Pointer to driver-private data structure passed + * as argument to devm_scrub_device_register(). + * @attr: Scrub attribute + * @region_id: ID of the memory region + * + * Returns: 0 on success, an error otherwise + */ +umode_t cxl_mem_patrol_scrub_is_visible(const void *drv_data, u32 attr, int region_id) +{ + const struct cxl_patrol_scrub_context *cxl_ps_ctx = drv_data; + + if (attr == scrub_speed_available || + attr == scrub_speed) { + if (!cxl_ps_ctx->scrub_cycle_changable) + return 0; + } + + switch (attr) { + case scrub_speed_available: + return 0444; + case scrub_enable: + return 0200; + case scrub_speed: + return 0644; + default: + return 0; + } +} + +/** + * cxl_mem_patrol_scrub_read() - Read callback for data attributes + * @dev: Pointer to scrub device + * @attr: Scrub attribute + * @region_id: ID of the memory region + * @val: Pointer to the returned data + * + * Returns: 0 on success, an error otherwise + */ +int cxl_mem_patrol_scrub_read(struct device *dev, u32 attr, int region_id, u64 *val) +{ + + switch (attr) { + case scrub_speed: + return cxl_mem_ps_speed_read(dev->parent, val); + default: + return -ENOTSUPP; + } +} + +/** + * cxl_mem_patrol_scrub_write() - Write callback for data attributes + * @dev: Pointer to scrub device + * @attr: Scrub attribute + * @region_id: ID of the memory region + * @val: Value to write + * + * Returns: 0 on success, an error otherwise + */ +int cxl_mem_patrol_scrub_write(struct device *dev, u32 attr, int region_id, u64 val) +{ + switch (attr) { + case scrub_enable: + return cxl_mem_ps_enable_write(dev->parent, val); + case scrub_speed: + return cxl_mem_ps_speed_write(dev->parent, val); + default: + return -ENOTSUPP; + } +} + +/** + * cxl_mem_patrol_scrub_read_strings() - Read callback for string attributes + * @dev: Pointer to scrub device + * @attr: Scrub attribute + * @region_id: ID of the memory region + * @buf: Pointer to the buffer for copying returned string + * + * Returns: 0 on success, an error otherwise + */ +int cxl_mem_patrol_scrub_read_strings(struct device *dev, u32 attr, int region_id, + char *buf) +{ + switch (attr) { + case scrub_speed_available: + return cxl_mem_ps_speed_available_read(dev->parent, buf); + default: + return -ENOTSUPP; + } +} + +static const struct scrub_ops cxl_ps_scrub_ops = { + .is_visible = cxl_mem_patrol_scrub_is_visible, + .read = cxl_mem_patrol_scrub_read, + .write = cxl_mem_patrol_scrub_write, + .read_string = cxl_mem_patrol_scrub_read_strings, +}; + +int cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd) +{ + int ret = 0; + struct device *cxl_scrub_dev; + struct cxl_memdev_ps_params params; + struct cxl_mbox_supp_feat_entry feat_entry; + char scrub_name[CXL_MEMDEV_MAX_NAME_LENGTH]; + struct cxl_patrol_scrub_context *cxl_ps_ctx; + + ret = cxl_mem_get_supported_feature_entry(cxlmd, &cxl_patrol_scrub_uuid, + &feat_entry); + if (ret < 0) + goto cxl_ps_init_exit; + + if (!(feat_entry.attrb_flags & CXL_FEAT_ENTRY_FLAG_CHANGABLE)) + goto cxl_ps_init_exit; + + cxl_ps_ctx = devm_kzalloc(&cxlmd->dev, sizeof(*cxl_ps_ctx), GFP_KERNEL); + if (!cxl_ps_ctx) + goto cxl_ps_init_exit; + + cxl_ps_ctx->get_feat_size = feat_entry.get_feat_size; + cxl_ps_ctx->set_feat_size = feat_entry.set_feat_size; + ret = cxl_mem_ps_get_attrbs(&cxlmd->dev, ¶ms); + if (ret) { + dev_err(&cxlmd->dev, "Get CXL patrol scrub params fail ret=%d\n", + ret); + goto cxl_ps_init_exit; + } + cxl_ps_ctx->scrub_cycle_changable = params.scrub_cycle_changable; + + snprintf(scrub_name, sizeof(scrub_name), "%s_%s", + CXL_PATROL_SCRUB, dev_name(&cxlmd->dev)); + cxl_scrub_dev = devm_scrub_device_register(&cxlmd->dev, scrub_name, + cxl_ps_ctx, &cxl_ps_scrub_ops, + CXL_MEMDEV_PATROL_SCRUB_NUM_REGIONS); + if (PTR_ERR_OR_ZERO(cxl_scrub_dev)) { + ret = PTR_ERR_OR_ZERO(cxl_scrub_dev); + goto cxl_ps_reg_fail; + } + +cxl_ps_reg_fail: +cxl_ps_init_exit: + return ret; +} +EXPORT_SYMBOL_NS_GPL(cxl_mem_patrol_scrub_init, CXL); diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h index fdac686560d4..1d0fad0dc5ae 100644 --- a/drivers/cxl/cxlmem.h +++ b/drivers/cxl/cxlmem.h @@ -969,6 +969,13 @@ 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); +/* cxl memory scrub functions */ +#ifdef CONFIG_CXL_SCRUB +int cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd); +#else +int cxl_mem_patrol_scrub_init(struct cxl_memdev *cxlmd) { return -ENOTSUP; } +#endif + #ifdef CONFIG_CXL_SUSPEND void cxl_mem_active_inc(void); void cxl_mem_active_dec(void); diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 0155fb66b580..86bba8794bb4 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -881,6 +881,12 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (rc) return rc; + /* + * Initialize optional CXL scrub features + */ + if (cxl_mem_patrol_scrub_init(cxlmd)) + dev_dbg(&pdev->dev, "cxl_mem_patrol_scrub_init failed\n"); + rc = devm_cxl_sanitize_setup_notifier(&pdev->dev, cxlmd); if (rc) return rc;