remoteproc: Properly represent the attached state

There is a need to know when a remote processor has been attached
to rather than booted by the remoteproc core.  In order to avoid
manipulating two variables, i.e rproc::autonomous and
rproc::state, get rid of the former and simply use the newly
introduced RPROC_ATTACHED state.
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: NPeng Fan <peng.fan@nxp.com>
Reviewed-by: NArnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20210312162453.1234145-5-mathieu.poirier@linaro.orgSigned-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

drivers/remoteproc/remoteproc_core.c

@@ -1450,7 +1450,7 @@ static int __rproc_attach(struct rproc *rproc)
 		goto stop_rproc;
 	}
 
-	rproc->state = RPROC_RUNNING;
+	rproc->state = RPROC_ATTACHED;
 
 	dev_info(dev, "remote processor %s is now attached\n", rproc->name);
 
@@ -1665,14 +1665,6 @@ 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;
@@ -2083,16 +2075,6 @@ int rproc_add(struct rproc *rproc)
 	if (ret < 0)
 		return ret;
 
-	/*
-	 * 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);

drivers/remoteproc/remoteproc_sysfs.c

@@ -138,11 +138,8 @@ static ssize_t firmware_show(struct device *dev, struct device_attribute *attr,
 	 * 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)
+	if (rproc->state == RPROC_ATTACHED)
 		firmware = "unknown";
 
 	return sprintf(buf, "%s\n", firmware);

include/linux/remoteproc.h

@@ -514,7 +514,6 @@ 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
  * @char_dev: character device of the rproc
@@ -551,7 +550,6 @@ 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;