Abstract the platform specific mechanics for firmware activation behind a handful of generic ops. At the bus level ->activate_state() indicates the unified state (idle, busy, armed) of all DIMMs on the bus, and ->capability() indicates the system state expectations for activate. At the DIMM level ->activate_state() indicates the per-DIMM state, ->activate_result() indicates the outcome of the last activation attempt, and ->arm() attempts to transition the DIMM from 'idle' to 'armed'. Cc: Jonathan Corbet <corbet@xxxxxxx> Cc: Dave Jiang <dave.jiang@xxxxxxxxx> Cc: Ira Weiny <ira.weiny@xxxxxxxxx> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- Documentation/ABI/testing/sysfs-bus-nvdimm | 2 .../driver-api/nvdimm/firmware-activate.rst | 74 ++++++++++++++++ drivers/nvdimm/core.c | 92 +++++++++++++++++++ drivers/nvdimm/dimm_devs.c | 95 ++++++++++++++++++++ drivers/nvdimm/nd-core.h | 1 include/linux/libnvdimm.h | 44 +++++++++ 6 files changed, 308 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-nvdimm create mode 100644 Documentation/driver-api/nvdimm/firmware-activate.rst diff --git a/Documentation/ABI/testing/sysfs-bus-nvdimm b/Documentation/ABI/testing/sysfs-bus-nvdimm new file mode 100644 index 000000000000..d64380262be8 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-nvdimm @@ -0,0 +1,2 @@ +The libnvdimm sub-system implements a common sysfs interface for +platform nvdimm resources. See Documentation/driver-api/nvdimm/. diff --git a/Documentation/driver-api/nvdimm/firmware-activate.rst b/Documentation/driver-api/nvdimm/firmware-activate.rst new file mode 100644 index 000000000000..8b42c96e1f6f --- /dev/null +++ b/Documentation/driver-api/nvdimm/firmware-activate.rst @@ -0,0 +1,74 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================================== +NVDIMM Runtime Firmware Activation +================================== + +Some persistent memory devices run a firmware locally on the device / +"DIMM" to perform tasks like media management, capacity provisioning, +and health monitoring. The process of updating that firmware typically +involves a reboot because it has implications for in-flight memory +transactions. However, reboots are disruptive and at least the Intel +persistent memory platform implementation, described by the Intel ACPI +DSM specification [1], has added support for activating firmware at +runtime. + +A native sysfs interface is implemented in libnvdimm to allow platform +to advertise and control their local runtime firmware activation +capability. + +The libnvdimm bus object, ndbusX, implements an ndbusX/firmware_activate +attribute that shows the state of the firmware activation as one of 'idle', +'armed', 'overflow', and 'busy'. + +- idle: + No devices are set / armed to activate firmware + +- armed: + At least one device is armed + +- busy: + In the busy state armed devices are in the process of transitioning + back to idle and completing an activation cycle. + +- overflow: + If the platform has a concept of incremental work needed to perform + the activation it could be the case that too many DIMMs are armed for + activation. In that scenario the potential for firmware activation to + timeout is indicated by the 'overflow' state. + +This property is optionally read-write if the platform implementation +allows firmware-activation at run-time. Some activations may involve a +memory controller quiesce that may trigger undefined behavior in devices +actively performing DMA. On these platform firmware_activate is not +writable and instead activation occurs over a suspend event. + +The libnvdimm memory-device / DIMM object, nmemX, implements +nmemX/firmware_activate and nmemX/firmware_activate_result attributes to +communicate the per-device firmware activation state. Similar to the +ndbusX/firmware_activate attribute, the nmemX/firmware_activate +attribute indicates 'idle', 'armed', or 'busy'. The state transitions +from 'armed' to 'idle' when the system is prepared to activate firmware, +firmware staged + state set to armed, and a system sleep state +transition is triggered. After that activation event the +nmemX/firmware_activate_result attribute reflects the state of the last +activation as one of: + +- none: + No runtime activation triggered since the last time the device was reset + +- success: + The last runtime activation completed successfully. + +- fail: + The last runtime activation failed for device-specific reasons. + +- not_staged: + The last runtime activation failed due to a sequencing error of the + firmware image not being staged. + +- need_reset: + Runtime firmware activation failed, but the firmware can still be + activated via the legacy method of power-cycling the system. + +[1]: https://docs.pmem.io/persistent-memory/ diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c index fe9bd6febdd2..b1cc7b35bd51 100644 --- a/drivers/nvdimm/core.c +++ b/drivers/nvdimm/core.c @@ -378,15 +378,107 @@ static ssize_t wait_probe_show(struct device *dev, } static DEVICE_ATTR_RO(wait_probe); +static ssize_t firmware_activate_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + enum nvdimm_fwa_state state; + + if (!nd_desc->fw_ops) + return -EOPNOTSUPP; + + nvdimm_bus_lock(dev); + state = nd_desc->fw_ops->activate_state(nd_desc); + nvdimm_bus_unlock(dev); + + switch (state) { + case NVDIMM_FWA_IDLE: + return sprintf(buf, "idle\n"); + case NVDIMM_FWA_BUSY: + return sprintf(buf, "busy\n"); + case NVDIMM_FWA_ARMED: + return sprintf(buf, "armed\n"); + case NVDIMM_FWA_ARM_OVERFLOW: + return sprintf(buf, "overflow\n"); + default: + return -ENXIO; + } +} + +static ssize_t firmware_activate_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + enum nvdimm_fwa_state state; + ssize_t rc; + + if (!nd_desc->fw_ops) + return -EOPNOTSUPP; + + nvdimm_bus_lock(dev); + state = nd_desc->fw_ops->activate_state(nd_desc); + + switch (state) { + case NVDIMM_FWA_BUSY: + rc = -EBUSY; + break; + case NVDIMM_FWA_ARMED: + case NVDIMM_FWA_ARM_OVERFLOW: + rc = nd_desc->fw_ops->activate(nd_desc); + break; + case NVDIMM_FWA_IDLE: + default: + rc = -ENXIO; + } + nvdimm_bus_unlock(dev); + + if (rc == 0) + rc = len; + return rc; +} + +static DEVICE_ATTR_ADMIN_RW(firmware_activate); + +static umode_t nvdimm_bus_visible(struct kobject *kobj, struct attribute *a, int n) +{ + struct device *dev = container_of(kobj, typeof(*dev), kobj); + struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + + if (a == &dev_attr_firmware_activate.attr) { + enum nvdimm_fwa_capability cap; + + if (!nd_desc->fw_ops) + return 0; + + nvdimm_bus_lock(dev); + cap = nd_desc->fw_ops->capability(nd_desc); + nvdimm_bus_unlock(dev); + + if (cap < NVDIMM_FWA_CAP_QUIESCE) + return 0; + /* Force suspend flow for activate */ + if (cap == NVDIMM_FWA_CAP_QUIESCE) + return 0400; + /* Live activation permitted */ + return 0600; + } + return a->mode; +} + static struct attribute *nvdimm_bus_attributes[] = { &dev_attr_commands.attr, &dev_attr_wait_probe.attr, &dev_attr_provider.attr, + &dev_attr_firmware_activate.attr, NULL, }; static const struct attribute_group nvdimm_bus_attribute_group = { .attrs = nvdimm_bus_attributes, + .is_visible = nvdimm_bus_visible, }; const struct attribute_group *nvdimm_bus_attribute_groups[] = { diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c index b7b77e8d9027..85835f9add7a 100644 --- a/drivers/nvdimm/dimm_devs.c +++ b/drivers/nvdimm/dimm_devs.c @@ -406,6 +406,88 @@ static ssize_t security_store(struct device *dev, } static DEVICE_ATTR_RW(security); +static ssize_t firmware_activate_result_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nvdimm *nvdimm = to_nvdimm(dev); + enum nvdimm_fwa_result result; + + if (!nvdimm->fw_ops) + return -EOPNOTSUPP; + + nvdimm_bus_lock(dev); + result = nvdimm->fw_ops->activate_result(nvdimm); + nvdimm_bus_unlock(dev); + + switch (result) { + case NVDIMM_FWA_RESULT_NONE: + return sprintf(buf, "none\n"); + case NVDIMM_FWA_RESULT_SUCCESS: + return sprintf(buf, "success\n"); + case NVDIMM_FWA_RESULT_FAIL: + return sprintf(buf, "fail\n"); + case NVDIMM_FWA_RESULT_NOTSTAGED: + return sprintf(buf, "not_staged\n"); + case NVDIMM_FWA_RESULT_NEEDRESET: + return sprintf(buf, "need_reset\n"); + default: + return -ENXIO; + } +} +static DEVICE_ATTR_ADMIN_RO(firmware_activate_result); + +static ssize_t firmware_activate_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nvdimm *nvdimm = to_nvdimm(dev); + enum nvdimm_fwa_state state; + + if (!nvdimm->fw_ops) + return -EOPNOTSUPP; + + nvdimm_bus_lock(dev); + state = nvdimm->fw_ops->activate_state(nvdimm); + nvdimm_bus_unlock(dev); + + switch (state) { + case NVDIMM_FWA_IDLE: + return sprintf(buf, "idle\n"); + case NVDIMM_FWA_BUSY: + return sprintf(buf, "busy\n"); + case NVDIMM_FWA_ARMED: + return sprintf(buf, "armed\n"); + default: + return -ENXIO; + } +} + +static ssize_t firmware_activate_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct nvdimm *nvdimm = to_nvdimm(dev); + enum nvdimm_fwa_trigger arg; + int rc; + + if (!nvdimm->fw_ops) + return -EOPNOTSUPP; + + if (sysfs_streq(buf, "arm")) + arg = NVDIMM_FWA_ARM; + else if (sysfs_streq(buf, "disarm")) + arg = NVDIMM_FWA_DISARM; + else + return -EINVAL; + + nvdimm_bus_lock(dev); + rc = nvdimm->fw_ops->arm(nvdimm, arg); + nvdimm_bus_unlock(dev); + + if (rc < 0) + return rc; + return len; +} +static DEVICE_ATTR_ADMIN_RW(firmware_activate); + static struct attribute *nvdimm_attributes[] = { &dev_attr_state.attr, &dev_attr_flags.attr, @@ -413,6 +495,8 @@ static struct attribute *nvdimm_attributes[] = { &dev_attr_available_slots.attr, &dev_attr_security.attr, &dev_attr_frozen.attr, + &dev_attr_firmware_activate.attr, + &dev_attr_firmware_activate_result.attr, NULL, }; @@ -421,6 +505,17 @@ static umode_t nvdimm_visible(struct kobject *kobj, struct attribute *a, int n) struct device *dev = container_of(kobj, typeof(*dev), kobj); struct nvdimm *nvdimm = to_nvdimm(dev); + if (a == &dev_attr_firmware_activate.attr) { + struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + + if (!nd_desc->fw_ops) + return 0; + if (!nvdimm->fw_ops) + return 0; + return a->mode; + } + if (a != &dev_attr_security.attr && a != &dev_attr_frozen.attr) return a->mode; if (!nvdimm->sec.flags) diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h index ddb9d97d9129..564faa36a3ca 100644 --- a/drivers/nvdimm/nd-core.h +++ b/drivers/nvdimm/nd-core.h @@ -45,6 +45,7 @@ struct nvdimm { struct kernfs_node *overwrite_state; } sec; struct delayed_work dwork; + const struct nvdimm_fw_ops *fw_ops; }; static inline unsigned long nvdimm_security_flags( diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index ad9898ece7d3..15dbcb718316 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -86,6 +86,7 @@ struct nvdimm_bus_descriptor { int (*flush_probe)(struct nvdimm_bus_descriptor *nd_desc); int (*clear_to_send)(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, unsigned int cmd, void *data); + const struct nvdimm_bus_fw_ops *fw_ops; }; struct nd_cmd_desc { @@ -200,6 +201,49 @@ struct nvdimm_security_ops { int (*query_overwrite)(struct nvdimm *nvdimm); }; +enum nvdimm_fwa_state { + NVDIMM_FWA_INVALID, + NVDIMM_FWA_IDLE, + NVDIMM_FWA_ARMED, + NVDIMM_FWA_BUSY, + NVDIMM_FWA_ARM_OVERFLOW, +}; + +enum nvdimm_fwa_trigger { + NVDIMM_FWA_ARM, + NVDIMM_FWA_DISARM, +}; + +enum nvdimm_fwa_capability { + NVDIMM_FWA_CAP_INVALID, + NVDIMM_FWA_CAP_NONE, + NVDIMM_FWA_CAP_QUIESCE, + NVDIMM_FWA_CAP_LIVE, +}; + +enum nvdimm_fwa_result { + NVDIMM_FWA_RESULT_INVALID, + NVDIMM_FWA_RESULT_NONE, + NVDIMM_FWA_RESULT_SUCCESS, + NVDIMM_FWA_RESULT_NOTSTAGED, + NVDIMM_FWA_RESULT_NEEDRESET, + NVDIMM_FWA_RESULT_FAIL, +}; + +struct nvdimm_bus_fw_ops { + enum nvdimm_fwa_state (*activate_state) + (struct nvdimm_bus_descriptor *nd_desc); + enum nvdimm_fwa_capability (*capability) + (struct nvdimm_bus_descriptor *nd_desc); + int (*activate)(struct nvdimm_bus_descriptor *nd_desc); +}; + +struct nvdimm_fw_ops { + enum nvdimm_fwa_state (*activate_state)(struct nvdimm *nvdimm); + enum nvdimm_fwa_result (*activate_result)(struct nvdimm *nvdimm); + int (*arm)(struct nvdimm *nvdimm, enum nvdimm_fwa_trigger arg); +}; + void badrange_init(struct badrange *badrange); int badrange_add(struct badrange *badrange, u64 addr, u64 length); void badrange_forget(struct badrange *badrange, phys_addr_t start,
