[PATCH v3 15/15] remoteproc: Refactor rproc delete and cdev release path

[Mathieu Poirier]

Refactor function rproc_del() and rproc_cdev_release() to take
into account the policy specified in the device tree.

Signed-off-by: Mathieu Poirier <mathieu.poir...@linaro.org>
---
 drivers/remoteproc/remoteproc_cdev.c | 13 +++++++++++-
 drivers/remoteproc/remoteproc_core.c | 30 ++++++++++++++++++++++++++--
 include/linux/remoteproc.h           |  4 ++++
 3 files changed, 44 insertions(+), 3 deletions(-)

diff --git a/drivers/remoteproc/remoteproc_cdev.c 
b/drivers/remoteproc/remoteproc_cdev.c
index f7645f289563..3dfe555dfc07 100644
--- a/drivers/remoteproc/remoteproc_cdev.c
+++ b/drivers/remoteproc/remoteproc_cdev.c
@@ -88,7 +88,18 @@ static int rproc_cdev_release(struct inode *inode, struct 
file *filp)
 {
        struct rproc *rproc = container_of(inode->i_cdev, struct rproc, cdev);
 
-       if (rproc->cdev_put_on_release && rproc->state == RPROC_RUNNING)
+       if (!rproc->cdev_put_on_release)
+               return 0;
+
+       /*
+        * The application has crashed or is releasing its file handle.  Detach
+        * or shutdown the remote processor based on the policy specified in the
+        * DT.  No need to check rproc->state right away, it will be done
+        * in either rproc_detach() or rproc_shutdown().
+        */
+       if (rproc->autonomous_on_core_shutdown)
+               rproc_detach(rproc);
+       else
                rproc_shutdown(rproc);
 
        return 0;
diff --git a/drivers/remoteproc/remoteproc_core.c 
b/drivers/remoteproc/remoteproc_core.c
index 3d7d245edc4e..1a170103bf27 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -2294,6 +2294,22 @@ static int rproc_alloc_ops(struct rproc *rproc, const 
struct rproc_ops *ops)
        return 0;
 }
 
+static void rproc_set_automation_flags(struct rproc *rproc)
+{
+       struct device *dev = rproc->dev.parent;
+       struct device_node *np = dev->of_node;
+       bool core_shutdown;
+
+       /*
+        * When function rproc_cdev_release() or rproc_del() are called and
+        * the remote processor has been attached to, it will be detached from
+        * (rather than turned off) if "autonomous-on-core-shutdown is specified
+        * in the DT.
+        */
+       core_shutdown = of_property_read_bool(np, 
"autonomous-on-core-shutdown");
+       rproc->autonomous_on_core_shutdown = core_shutdown;
+}
+
 /**
  * rproc_alloc() - allocate a remote processor handle
  * @dev: the underlying device
@@ -2352,6 +2368,8 @@ struct rproc *rproc_alloc(struct device *dev, const char 
*name,
        if (rproc_alloc_ops(rproc, ops))
                goto put_device;
 
+       rproc_set_automation_flags(rproc);
+
        /* Assign a unique device index and name */
        rproc->index = ida_simple_get(&rproc_dev_index, 0, 0, GFP_KERNEL);
        if (rproc->index < 0) {
@@ -2435,8 +2453,16 @@ int rproc_del(struct rproc *rproc)
        if (!rproc)
                return -EINVAL;
 
-       /* TODO: make sure this works with rproc->power > 1 */
-       rproc_shutdown(rproc);
+       /*
+        * TODO: make sure this works with rproc->power > 1
+        *
+        * No need to check rproc->state right away, it will be done in either
+        * rproc_detach() or rproc_shutdown().
+        */
+       if (rproc->autonomous_on_core_shutdown)
+               rproc_detach(rproc);
+       else
+               rproc_shutdown(rproc);
 
        mutex_lock(&rproc->lock);
        rproc->state = RPROC_DELETED;
diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index 02312096d59f..5702f630d810 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -516,6 +516,9 @@ struct rproc_dump_segment {
  * @nb_vdev: number of vdev currently handled by rproc
  * @char_dev: character device of the rproc
  * @cdev_put_on_release: flag to indicate if remoteproc should be shutdown on 
@char_dev release
+ * @autonomous_on_core_shutdown: true if the remote processor should be 
detached
+ *                              from (rather than turned off) when the 
remoteproc
+ *                              core goes away.
  */
 struct rproc {
        struct list_head node;
@@ -554,6 +557,7 @@ struct rproc {
        u16 elf_machine;
        struct cdev cdev;
        bool cdev_put_on_release;
+       bool autonomous_on_core_shutdown;
 };
 
 /**
-- 
2.25.1