#include <linux/sched/signal.h>
#include <linux/sched/mm.h>
#include <linux/sysfs.h>
+#include <linux/dma-map-ops.h> /* for dma_default_coherent */
#include "base.h"
#include "power/power.h"
fwnode_links_purge_consumers(fwnode);
}
+static void fw_devlink_purge_absent_suppliers(struct fwnode_handle *fwnode)
+{
+ struct fwnode_handle *child;
+
+ /* Don't purge consumer links of an added child */
+ if (fwnode->dev)
+ return;
+
+ fwnode->flags |= FWNODE_FLAG_NOT_DEVICE;
+ fwnode_links_purge_consumers(fwnode);
+
+ fwnode_for_each_available_child_node(fwnode, child)
+ fw_devlink_purge_absent_suppliers(child);
+}
+
#ifdef CONFIG_SRCU
static DEFINE_MUTEX(device_links_lock);
DEFINE_STATIC_SRCU(device_links_srcu);
return ret;
list_for_each_entry(link, &dev->links.consumers, s_node) {
- if (link->flags == (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
+ if ((link->flags & ~DL_FLAG_INFERRED) ==
+ (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
continue;
if (link->consumer == target)
device_for_each_child(dev, NULL, device_reorder_to_tail);
list_for_each_entry(link, &dev->links.consumers, s_node) {
- if (link->flags == (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
+ if ((link->flags & ~DL_FLAG_INFERRED) ==
+ (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
continue;
device_reorder_to_tail(link->consumer, NULL);
}
#define DL_MANAGED_LINK_FLAGS (DL_FLAG_AUTOREMOVE_CONSUMER | \
DL_FLAG_AUTOREMOVE_SUPPLIER | \
DL_FLAG_AUTOPROBE_CONSUMER | \
- DL_FLAG_SYNC_STATE_ONLY)
+ DL_FLAG_SYNC_STATE_ONLY | \
+ DL_FLAG_INFERRED)
#define DL_ADD_VALID_FLAGS (DL_MANAGED_LINK_FLAGS | DL_FLAG_STATELESS | \
DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE)
if (!consumer || !supplier || flags & ~DL_ADD_VALID_FLAGS ||
(flags & DL_FLAG_STATELESS && flags & DL_MANAGED_LINK_FLAGS) ||
(flags & DL_FLAG_SYNC_STATE_ONLY &&
- flags != DL_FLAG_SYNC_STATE_ONLY) ||
+ (flags & ~DL_FLAG_INFERRED) != DL_FLAG_SYNC_STATE_ONLY) ||
(flags & DL_FLAG_AUTOPROBE_CONSUMER &&
flags & (DL_FLAG_AUTOREMOVE_CONSUMER |
DL_FLAG_AUTOREMOVE_SUPPLIER)))
if (link->consumer != consumer)
continue;
+ if (link->flags & DL_FLAG_INFERRED &&
+ !(flags & DL_FLAG_INFERRED))
+ link->flags &= ~DL_FLAG_INFERRED;
+
if (flags & DL_FLAG_PM_RUNTIME) {
if (!(link->flags & DL_FLAG_PM_RUNTIME)) {
pm_runtime_new_link(consumer);
mutex_lock(&fwnode_link_lock);
if (dev->fwnode && !list_empty(&dev->fwnode->suppliers) &&
!fw_devlink_is_permissive()) {
+ dev_dbg(dev, "probe deferral - wait for supplier %pfwP\n",
+ list_first_entry(&dev->fwnode->suppliers,
+ struct fwnode_link,
+ c_hook)->supplier);
mutex_unlock(&fwnode_link_lock);
return -EPROBE_DEFER;
}
if (link->status != DL_STATE_AVAILABLE &&
!(link->flags & DL_FLAG_SYNC_STATE_ONLY)) {
device_links_missing_supplier(dev);
+ dev_dbg(dev, "probe deferral - supplier %s not ready\n",
+ dev_name(link->supplier));
ret = -EPROBE_DEFER;
break;
}
}
static DEVICE_ATTR_RO(waiting_for_supplier);
+/**
+ * device_links_force_bind - Prepares device to be force bound
+ * @dev: Consumer device.
+ *
+ * device_bind_driver() force binds a device to a driver without calling any
+ * driver probe functions. So the consumer really isn't going to wait for any
+ * supplier before it's bound to the driver. We still want the device link
+ * states to be sensible when this happens.
+ *
+ * In preparation for device_bind_driver(), this function goes through each
+ * supplier device links and checks if the supplier is bound. If it is, then
+ * the device link status is set to CONSUMER_PROBE. Otherwise, the device link
+ * is dropped. Links without the DL_FLAG_MANAGED flag set are ignored.
+ */
+void device_links_force_bind(struct device *dev)
+{
+ struct device_link *link, *ln;
+
+ device_links_write_lock();
+
+ list_for_each_entry_safe(link, ln, &dev->links.suppliers, c_node) {
+ if (!(link->flags & DL_FLAG_MANAGED))
+ continue;
+
+ if (link->status != DL_STATE_AVAILABLE) {
+ device_link_drop_managed(link);
+ continue;
+ }
+ WRITE_ONCE(link->status, DL_STATE_CONSUMER_PROBE);
+ }
+ dev->links.status = DL_DEV_PROBING;
+
+ device_links_write_unlock();
+}
+
/**
* device_links_driver_bound - Update device links after probing its driver.
* @dev: Device to update the links for.
LIST_HEAD(sync_list);
/*
- * If a device probes successfully, it's expected to have created all
+ * If a device binds successfully, it's expected to have created all
* the device links it needs to or make new device links as it needs
- * them. So, it no longer needs to wait on any suppliers.
+ * them. So, fw_devlink no longer needs to create device links to any
+ * of the device's suppliers.
+ *
+ * Also, if a child firmware node of this bound device is not added as
+ * a device by now, assume it is never going to be added and make sure
+ * other devices don't defer probe indefinitely by waiting for such a
+ * child device.
*/
- if (dev->fwnode && dev->fwnode->dev == dev)
+ if (dev->fwnode && dev->fwnode->dev == dev) {
+ struct fwnode_handle *child;
fwnode_links_purge_suppliers(dev->fwnode);
+ fwnode_for_each_available_child_node(dev->fwnode, child)
+ fw_devlink_purge_absent_suppliers(child);
+ }
device_remove_file(dev, &dev_attr_waiting_for_supplier);
device_links_write_lock();
device_links_write_unlock();
}
-static u32 fw_devlink_flags = DL_FLAG_SYNC_STATE_ONLY;
+#define FW_DEVLINK_FLAGS_PERMISSIVE (DL_FLAG_INFERRED | \
+ DL_FLAG_SYNC_STATE_ONLY)
+#define FW_DEVLINK_FLAGS_ON (DL_FLAG_INFERRED | \
+ DL_FLAG_AUTOPROBE_CONSUMER)
+#define FW_DEVLINK_FLAGS_RPM (FW_DEVLINK_FLAGS_ON | \
+ DL_FLAG_PM_RUNTIME)
+
+static u32 fw_devlink_flags = FW_DEVLINK_FLAGS_ON;
static int __init fw_devlink_setup(char *arg)
{
if (!arg)
if (strcmp(arg, "off") == 0) {
fw_devlink_flags = 0;
} else if (strcmp(arg, "permissive") == 0) {
- fw_devlink_flags = DL_FLAG_SYNC_STATE_ONLY;
+ fw_devlink_flags = FW_DEVLINK_FLAGS_PERMISSIVE;
} else if (strcmp(arg, "on") == 0) {
- fw_devlink_flags = DL_FLAG_AUTOPROBE_CONSUMER;
+ fw_devlink_flags = FW_DEVLINK_FLAGS_ON;
} else if (strcmp(arg, "rpm") == 0) {
- fw_devlink_flags = DL_FLAG_AUTOPROBE_CONSUMER |
- DL_FLAG_PM_RUNTIME;
+ fw_devlink_flags = FW_DEVLINK_FLAGS_RPM;
}
return 0;
}
early_param("fw_devlink", fw_devlink_setup);
+static bool fw_devlink_strict;
+static int __init fw_devlink_strict_setup(char *arg)
+{
+ return strtobool(arg, &fw_devlink_strict);
+}
+early_param("fw_devlink.strict", fw_devlink_strict_setup);
+
u32 fw_devlink_get_flags(void)
{
return fw_devlink_flags;
static bool fw_devlink_is_permissive(void)
{
- return fw_devlink_flags == DL_FLAG_SYNC_STATE_ONLY;
+ return fw_devlink_flags == FW_DEVLINK_FLAGS_PERMISSIVE;
+}
+
+bool fw_devlink_is_strict(void)
+{
+ return fw_devlink_strict && !fw_devlink_is_permissive();
}
static void fw_devlink_parse_fwnode(struct fwnode_handle *fwnode)
fw_devlink_parse_fwtree(child);
}
+/**
+ * fw_devlink_relax_cycle - Convert cyclic links to SYNC_STATE_ONLY links
+ * @con: Device to check dependencies for.
+ * @sup: Device to check against.
+ *
+ * Check if @sup depends on @con or any device dependent on it (its child or
+ * its consumer etc). When such a cyclic dependency is found, convert all
+ * device links created solely by fw_devlink into SYNC_STATE_ONLY device links.
+ * This is the equivalent of doing fw_devlink=permissive just between the
+ * devices in the cycle. We need to do this because, at this point, fw_devlink
+ * can't tell which of these dependencies is not a real dependency.
+ *
+ * Return 1 if a cycle is found. Otherwise, return 0.
+ */
+static int fw_devlink_relax_cycle(struct device *con, void *sup)
+{
+ struct device_link *link;
+ int ret;
+
+ if (con == sup)
+ return 1;
+
+ ret = device_for_each_child(con, sup, fw_devlink_relax_cycle);
+ if (ret)
+ return ret;
+
+ list_for_each_entry(link, &con->links.consumers, s_node) {
+ if ((link->flags & ~DL_FLAG_INFERRED) ==
+ (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED))
+ continue;
+
+ if (!fw_devlink_relax_cycle(link->consumer, sup))
+ continue;
+
+ ret = 1;
+
+ if (!(link->flags & DL_FLAG_INFERRED))
+ continue;
+
+ pm_runtime_drop_link(link);
+ link->flags = DL_FLAG_MANAGED | FW_DEVLINK_FLAGS_PERMISSIVE;
+ dev_dbg(link->consumer, "Relaxing link with %s\n",
+ dev_name(link->supplier));
+ }
+ return ret;
+}
+
/**
* fw_devlink_create_devlink - Create a device link from a consumer to fwnode
* @con - Consumer device for the device link
sup_dev = get_dev_from_fwnode(sup_handle);
if (sup_dev) {
+ /*
+ * If it's one of those drivers that don't actually bind to
+ * their device using driver core, then don't wait on this
+ * supplier device indefinitely.
+ */
+ if (sup_dev->links.status == DL_DEV_NO_DRIVER &&
+ sup_handle->flags & FWNODE_FLAG_INITIALIZED) {
+ ret = -EINVAL;
+ goto out;
+ }
+
/*
* If this fails, it is due to cycles in device links. Just
* give up on this link and treat it as invalid.
*/
- if (!device_link_add(con, sup_dev, flags))
+ if (!device_link_add(con, sup_dev, flags) &&
+ !(flags & DL_FLAG_SYNC_STATE_ONLY)) {
+ dev_info(con, "Fixing up cyclic dependency with %s\n",
+ dev_name(sup_dev));
+ device_links_write_lock();
+ fw_devlink_relax_cycle(con, sup_dev);
+ device_links_write_unlock();
+ device_link_add(con, sup_dev,
+ FW_DEVLINK_FLAGS_PERMISSIVE);
ret = -EINVAL;
+ }
goto out;
}
+ /* Supplier that's already initialized without a struct device. */
+ if (sup_handle->flags & FWNODE_FLAG_INITIALIZED)
+ return -EINVAL;
+
/*
* DL_FLAG_SYNC_STATE_ONLY doesn't block probing and supports
* cycles. So cycle detection isn't necessary and shouldn't be
con_dev = NULL;
} else {
own_link = false;
- dl_flags = DL_FLAG_SYNC_STATE_ONLY;
+ dl_flags = FW_DEVLINK_FLAGS_PERMISSIVE;
}
}
if (own_link)
dl_flags = fw_devlink_get_flags();
else
- dl_flags = DL_FLAG_SYNC_STATE_ONLY;
+ dl_flags = FW_DEVLINK_FLAGS_PERMISSIVE;
list_for_each_entry_safe(link, tmp, &fwnode->suppliers, c_hook) {
int ret;
INIT_LIST_HEAD(&dev->links.suppliers);
INIT_LIST_HEAD(&dev->links.defer_sync);
dev->links.status = DL_DEV_NO_DRIVER;
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
+ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
+ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
+ dev->dma_coherent = dma_default_coherent;
+#endif
}
EXPORT_SYMBOL_GPL(device_initialize);
projects / linux-2.6-microblaze.git / blobdiff