PM, libnvdimm: Add runtime firmware activation support
Abstract platform specific mechanics for nvdimm 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'.
A new hibernate_quiet_exec() facility is added to support firmware
activation in an OS defined system quiesce state. It leverages the fact
that the hibernate-freeze state wants to assert that a memory
hibernation snapshot can be taken. This is in contrast to a platform
firmware defined quiesce state that may forcefully quiet the memory
controller independent of whether an individual device-driver properly
supports hibernate-freeze.
The libnvdimm sysfs interface is extended to support detection of a
firmware activate capability. The mechanism supports enumeration and
triggering of firmware activate, optionally in the
hibernate_quiet_exec() context.
[rafael: hibernate_quiet_exec() proposal]
[vishal: fix up sparse warning, grammar in Documentation/]
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Co-developed-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index fe9bd6f..c21ba06 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -4,6 +4,7 @@
*/
#include <linux/libnvdimm.h>
#include <linux/badblocks.h>
+#include <linux/suspend.h>
#include <linux/export.h>
#include <linux/module.h>
#include <linux/blkdev.h>
@@ -389,8 +390,156 @@ static const struct attribute_group nvdimm_bus_attribute_group = {
.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,
};