This patch prevents the firmware image name from being displayed when
the remoteproc core is attaching to a remote processor. This is needed
needed since there is no guarantee about the nature of the firmware
image that is loaded by the external entity.
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
Tested-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
---
drivers/remoteproc/remoteproc_core.c | 18 ++++++++++++++++++
drivers/remoteproc/remoteproc_sysfs.c | 16 ++++++++++++++--
include/linux/remoteproc.h | 2 ++
3 files changed, 34 insertions(+), 2 deletions(-)
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 6b6e4ec8cf3a..099c76ab198f 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -1624,6 +1624,14 @@ static int rproc_stop(struct rproc *rproc, bool crashed)
rproc->state = RPROC_OFFLINE;
+ /*
+ * The remote processor has been stopped and is now offline, which means
+ * that the next time it is brought back online the remoteproc core will
+ * be responsible to load its firmware. As such it is no longer
+ * autonomous.
+ */
+ rproc->autonomous = false;
+
dev_info(dev, "stopped remote processor %s\n", rproc->name);
return 0;
@@ -2142,6 +2150,16 @@ int rproc_add(struct rproc *rproc)
/* create debugfs entries */
rproc_create_debug_dir(rproc);
+ /*
+ * Remind ourselves the remote processor has been attached to rather
+ * than booted by the remoteproc core. This is important because the
+ * RPROC_DETACHED state will be lost as soon as the remote processor
+ * has been attached to. Used in firmware_show() and reset in
+ * rproc_stop().
+ */
+ if (rproc->state == RPROC_DETACHED)
+ rproc->autonomous = true;
+
/* if rproc is marked always-on, request it to boot */
if (rproc->auto_boot) {
ret = rproc_trigger_auto_boot(rproc);
diff --git a/drivers/remoteproc/remoteproc_sysfs.c b/drivers/remoteproc/remoteproc_sysfs.c
index 264759713934..eea514cec50e 100644
--- a/drivers/remoteproc/remoteproc_sysfs.c
+++ b/drivers/remoteproc/remoteproc_sysfs.c
@@ -15,8 +15,20 @@ static ssize_t firmware_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct rproc *rproc = to_rproc(dev);
-
- return sprintf(buf, "%s\n", rproc->firmware);
+ const char *firmware = rproc->firmware;
+
+ /*
+ * If the remote processor has been started by an external
+ * entity we have no idea of what image it is running. As such
+ * simply display a generic string rather then rproc->firmware.
+ *
+ * Here we rely on the autonomous flag because a remote processor
+ * may have been attached to and currently in a running state.
+ */
+ if (rproc->autonomous)
+ firmware = "unknown";
+
+ return sprintf(buf, "%s\n", firmware);
}
/* Change firmware name via sysfs */
diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index bf6a310ba870..cf5e31556780 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -491,6 +491,7 @@ struct rproc_dump_segment {
* @table_sz: size of @cached_table
* @has_iommu: flag to indicate if remote processor is behind an MMU
* @auto_boot: flag to indicate if remote processor should be auto-started
+ * @autonomous: true if an external entity has booted the remote processor
* @dump_segments: list of segments in the firmware
* @nb_vdev: number of vdev currently handled by rproc
*/
@@ -524,6 +525,7 @@ struct rproc {
size_t table_sz;
bool has_iommu;
bool auto_boot;
+ bool autonomous;
struct list_head dump_segments;
int nb_vdev;
u8 elf_class;
--
2.25.1
