remoteproc: add api for retrieving a rproc unique id

A new api, rproc_get_id(), is added to allow remoteproc/rpmsg clients
to be able to retrieve a fixed unique id associated with a rproc
device. Each of the rprocs is given an ida index as well, but this
is dynamic depending on the order rproc_alloc is called (probe order),
and also depends on what remote processor devices are instantiated.
This unique id needs to be supported for both DT and non-DT devices.
The platform device id or the remoteproc alias id are therefore
chosen for non-DT and DT devices respectively, with the assumption
that the remoteproc devices are created with known platform device
ids or alias ids in DT.

Signed-off-by: Suman Anna <s-anna@ti.com>

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index b870eebfb86b3556acfd205b5f6cb76e4170d606..a0af2471cdd3abb1c5735f211caef97c18e46ae6 100644 (file)
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -41,6 +41,8 @@
 #include <linux/crc32.h>
 #include <linux/virtio_ids.h>
 #include <linux/virtio_ring.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
 #include <asm/byteorder.h>
 
 #include "remoteproc_internal.h"
@@ -1278,6 +1280,36 @@ static void rproc_crash_handler_work(struct work_struct *work)
                rproc_trigger_recovery(rproc);
 }
 
+/**
+ * rproc_get_id() - return the id for the rproc device
+ * @rproc: handle of a remote processor
+ *
+ * Each rproc device is associated with a platform device, which is created
+ * either from device tree (majority newer platforms) or using legacy style
+ * platform device creation (fewer legacy platforms). This function retrieves
+ * an unique id for each remote processor and is useful for clients needing
+ * to distinguish each of the remoteprocs. This unique id is derived using
+ * the platform device id for non-DT devices, or an alternate alias id for
+ * DT devices (since they do not have a valid platform device id). It is
+ * assumed that the platform devices were created with known ids or were
+ * given proper alias ids using the stem "rproc".
+ *
+ * Return: alias id for DT devices or platform device id for non-DT devices
+ * associated with the rproc
+ */
+int rproc_get_id(struct rproc *rproc)
+{
+       struct device *dev = rproc->dev.parent;
+       struct device_node *np = dev->of_node;
+       struct platform_device *pdev = to_platform_device(dev);
+
+       if (np)
+               return of_alias_get_id(np, "rproc");
+       else
+               return pdev->id;
+}
+EXPORT_SYMBOL(rproc_get_id);
+
 /**
  * rproc_boot() - boot a remote processor
  * @rproc: handle of a remote processor

diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index 25a00c8b5b7f64ce8cce96e42fd8b3030cd93e76..475dfcf8079e4477ca928e41a2de86957362b1a4 100644 (file)
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -559,6 +559,7 @@ int rproc_boot(struct rproc *rproc);
 void rproc_shutdown(struct rproc *rproc);
 void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type);
 int rproc_coredump_add_segment(struct rproc *rproc, dma_addr_t da, size_t size);
+int rproc_get_id(struct rproc *rproc);
 
 static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev)
 {