--- /dev/null
+The libnvdimm sub-system implements a common sysfs interface for
+platform nvdimm resources. See Documentation/driver-api/nvdimm/.
--- /dev/null
+.. 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.
+
+The 'ndbusX/firmware/activate' property can be written with a value of
+either 'live', or 'quiesce'. A value of 'quiesce' triggers the kernel to
+run firmware activation from within the equivalent of the hibernation
+'freeze' state where drivers and applications are notified to stop their
+modifications of system memory. A value of 'live' attempts
+firmware activation without this hibernation cycle. The
+'ndbusX/firmware/activate' property will be elided completely if no
+firmware activation capability is detected.
+
+Another property 'ndbusX/firmware/capability' indicates a value of
+'live' or 'quiesce', where 'live' indicates that the firmware
+does not require or inflict any quiesce period on the system to update
+firmware. A capability value of 'quiesce' indicates that firmware does
+expect and injects a quiet period for the memory controller, but 'live'
+may still be written to 'ndbusX/firmware/activate' as an override to
+assume the risk of racing firmware update with in-flight device and
+application activity. The 'ndbusX/firmware/capability' property will be
+elided completely if no firmware activation capability is detected.
+
+The libnvdimm memory-device / DIMM object, nmemX, implements
+'nmemX/firmware/activate' and 'nmemX/firmware/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 'ndbusX/firmware/activate' is
+triggered. After that activation event the nmemX/firmware/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/
*/
#include <linux/libnvdimm.h>
#include <linux/badblocks.h>
+#include <linux/suspend.h>
#include <linux/export.h>
#include <linux/module.h>
#include <linux/blkdev.h>
.attrs = nvdimm_bus_attributes,
};
+static ssize_t capability_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_capability cap;
+
+ if (!nd_desc->fw_ops)
+ return -EOPNOTSUPP;
+
+ nvdimm_bus_lock(dev);
+ cap = nd_desc->fw_ops->capability(nd_desc);
+ nvdimm_bus_unlock(dev);
+
+ switch (cap) {
+ case NVDIMM_FWA_CAP_QUIESCE:
+ return sprintf(buf, "quiesce\n");
+ case NVDIMM_FWA_CAP_LIVE:
+ return sprintf(buf, "live\n");
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static DEVICE_ATTR_RO(capability);
+
+static ssize_t 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_capability cap;
+ enum nvdimm_fwa_state state;
+
+ if (!nd_desc->fw_ops)
+ return -EOPNOTSUPP;
+
+ nvdimm_bus_lock(dev);
+ cap = nd_desc->fw_ops->capability(nd_desc);
+ state = nd_desc->fw_ops->activate_state(nd_desc);
+ nvdimm_bus_unlock(dev);
+
+ if (cap < NVDIMM_FWA_CAP_QUIESCE)
+ return -EOPNOTSUPP;
+
+ 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 int exec_firmware_activate(void *data)
+{
+ struct nvdimm_bus_descriptor *nd_desc = data;
+
+ return nd_desc->fw_ops->activate(nd_desc);
+}
+
+static ssize_t 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;
+ bool quiesce;
+ ssize_t rc;
+
+ if (!nd_desc->fw_ops)
+ return -EOPNOTSUPP;
+
+ if (sysfs_streq(buf, "live"))
+ quiesce = false;
+ else if (sysfs_streq(buf, "quiesce"))
+ quiesce = true;
+ else
+ return -EINVAL;
+
+ 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:
+ if (quiesce)
+ rc = hibernate_quiet_exec(exec_firmware_activate, nd_desc);
+ else
+ 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(activate);
+
+static umode_t nvdimm_bus_firmware_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;
+ enum nvdimm_fwa_capability cap;
+
+ /*
+ * Both 'activate' and 'capability' disappear when no ops
+ * detected, or a negative capability is indicated.
+ */
+ 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;
+
+ return a->mode;
+}
+static struct attribute *nvdimm_bus_firmware_attributes[] = {
+ &dev_attr_activate.attr,
+ &dev_attr_capability.attr,
+ NULL,
+};
+
+static const struct attribute_group nvdimm_bus_firmware_attribute_group = {
+ .name = "firmware",
+ .attrs = nvdimm_bus_firmware_attributes,
+ .is_visible = nvdimm_bus_firmware_visible,
+};
+
const struct attribute_group *nvdimm_bus_attribute_groups[] = {
&nvdimm_bus_attribute_group,
+ &nvdimm_bus_firmware_attribute_group,
NULL,
};
.is_visible = nvdimm_visible,
};
+static ssize_t 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(result);
+
+static ssize_t 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 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(activate);
+
+static struct attribute *nvdimm_firmware_attributes[] = {
+ &dev_attr_activate.attr,
+ &dev_attr_result.attr,
+};
+
+static umode_t nvdimm_firmware_visible(struct kobject *kobj, struct attribute *a, int n)
+{
+ struct device *dev = container_of(kobj, typeof(*dev), kobj);
+ struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
+ struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+ enum nvdimm_fwa_capability cap;
+
+ if (!nd_desc->fw_ops)
+ return 0;
+ if (!nvdimm->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;
+
+ return a->mode;
+}
+
+static const struct attribute_group nvdimm_firmware_attribute_group = {
+ .name = "firmware",
+ .attrs = nvdimm_firmware_attributes,
+ .is_visible = nvdimm_firmware_visible,
+};
+
static const struct attribute_group *nvdimm_attribute_groups[] = {
&nd_device_attribute_group,
&nvdimm_attribute_group,
+ &nvdimm_firmware_attribute_group,
NULL,
};
struct kernfs_node *overwrite_state;
} sec;
struct delayed_work dwork;
+ const struct nvdimm_fw_ops *fw_ops;
};
static inline unsigned long nvdimm_security_flags(
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 {
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,
asmlinkage int swsusp_save(void);
extern struct pbe *restore_pblist;
int pfn_is_nosave(unsigned long pfn);
+
+int hibernate_quiet_exec(int (*func)(void *data), void *data);
#else /* CONFIG_HIBERNATION */
static inline void register_nosave_region(unsigned long b, unsigned long e) {}
static inline void register_nosave_region_late(unsigned long b, unsigned long e) {}
static inline int hibernate(void) { return -ENOSYS; }
static inline bool system_entering_hibernation(void) { return false; }
static inline bool hibernation_available(void) { return false; }
+
+static inline int hibernate_quiet_exec(int (*func)(void *data), void *data) {
+ return -ENOTSUPP;
+}
#endif /* CONFIG_HIBERNATION */
#ifdef CONFIG_HIBERNATION_SNAPSHOT_DEV
return error;
}
+/**
+ * hibernate_quiet_exec - Execute a function with all devices frozen.
+ * @func: Function to execute.
+ * @data: Data pointer to pass to @func.
+ *
+ * Return the @func return value or an error code if it cannot be executed.
+ */
+int hibernate_quiet_exec(int (*func)(void *data), void *data)
+{
+ int error, nr_calls = 0;
+
+ lock_system_sleep();
+
+ if (!hibernate_acquire()) {
+ error = -EBUSY;
+ goto unlock;
+ }
+
+ pm_prepare_console();
+
+ error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
+ if (error) {
+ nr_calls--;
+ goto exit;
+ }
+
+ error = freeze_processes();
+ if (error)
+ goto exit;
+
+ lock_device_hotplug();
+
+ pm_suspend_clear_flags();
+
+ error = platform_begin(true);
+ if (error)
+ goto thaw;
+
+ error = freeze_kernel_threads();
+ if (error)
+ goto thaw;
+
+ error = dpm_prepare(PMSG_FREEZE);
+ if (error)
+ goto dpm_complete;
+
+ suspend_console();
+
+ error = dpm_suspend(PMSG_FREEZE);
+ if (error)
+ goto dpm_resume;
+
+ error = dpm_suspend_end(PMSG_FREEZE);
+ if (error)
+ goto dpm_resume;
+
+ error = platform_pre_snapshot(true);
+ if (error)
+ goto skip;
+
+ error = func(data);
+
+skip:
+ platform_finish(true);
+
+ dpm_resume_start(PMSG_THAW);
+
+dpm_resume:
+ dpm_resume(PMSG_THAW);
+
+ resume_console();
+
+dpm_complete:
+ dpm_complete(PMSG_THAW);
+
+ thaw_kernel_threads();
+
+thaw:
+ platform_end(true);
+
+ unlock_device_hotplug();
+
+ thaw_processes();
+
+exit:
+ __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
+
+ pm_restore_console();
+
+ hibernate_release();
+
+unlock:
+ unlock_system_sleep();
+
+ return error;
+}
+EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
/**
* software_resume - Resume from a saved hibernation image.
projects / linux-2.6-microblaze.git / commitdiff