[PATCH v3 1/2] remoteproc: core: full attach detach during recovery

[Tanmay Shah]

Current attach on recovery mechanism loads the clean resource table
during recovery, but doesn't re-allocate the resources. RPMsg
communication will fail after recovery due to this. Fix this
incorrect behavior by doing the full detach and attach of remote
processor during the recovery. This will load the clean resource table
and re-allocate all the resources, which will set up correct vring
information in the resource table.

Signed-off-by: Tanmay Shah <tanmay.s...@amd.com>
---

Changes in v3:
 - both rproc_attach_recovery() and
   rproc_boot_recovery() are called the same way.
 - remove unrelated changes

Changes in v2:
 - use rproc_boot instead of rproc_attach
 - move debug message early in the function

 drivers/remoteproc/remoteproc_core.c | 33 +++++++++++-----------------
 1 file changed, 13 insertions(+), 20 deletions(-)

diff --git a/drivers/remoteproc/remoteproc_core.c 
b/drivers/remoteproc/remoteproc_core.c
index aada2780b343..790ad7c6d12e 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -1777,11 +1777,11 @@ static int rproc_attach_recovery(struct rproc *rproc)
 {
        int ret;
 
-       ret = __rproc_detach(rproc);
+       ret = rproc_detach(rproc);
        if (ret)
                return ret;
 
-       return __rproc_attach(rproc);
+       return rproc_boot(rproc);
 }
 
 static int rproc_boot_recovery(struct rproc *rproc)
@@ -1790,10 +1790,14 @@ static int rproc_boot_recovery(struct rproc *rproc)
        struct device *dev = &rproc->dev;
        int ret;
 
-       ret = rproc_stop(rproc, true);
+       ret = mutex_lock_interruptible(&rproc->lock);
        if (ret)
                return ret;
 
+       ret = rproc_stop(rproc, true);
+       if (ret)
+               goto unlock_mutex;
+
        /* generate coredump */
        rproc->ops->coredump(rproc);
 
@@ -1801,7 +1805,7 @@ static int rproc_boot_recovery(struct rproc *rproc)
        ret = request_firmware(&firmware_p, rproc->firmware, dev);
        if (ret < 0) {
                dev_err(dev, "request_firmware failed: %d\n", ret);
-               return ret;
+               goto unlock_mutex;
        }
 
        /* boot the remote processor up again */
@@ -1809,6 +1813,8 @@ static int rproc_boot_recovery(struct rproc *rproc)
 
        release_firmware(firmware_p);
 
+unlock_mutex:
+       mutex_unlock(&rproc->lock);
        return ret;
 }
 
@@ -1827,26 +1833,13 @@ static int rproc_boot_recovery(struct rproc *rproc)
 int rproc_trigger_recovery(struct rproc *rproc)
 {
        struct device *dev = &rproc->dev;
-       int ret;
-
-       ret = mutex_lock_interruptible(&rproc->lock);
-       if (ret)
-               return ret;
-
-       /* State could have changed before we got the mutex */
-       if (rproc->state != RPROC_CRASHED)
-               goto unlock_mutex;
 
        dev_err(dev, "recovering %s\n", rproc->name);
 
        if (rproc_has_feature(rproc, RPROC_FEAT_ATTACH_ON_RECOVERY))
-               ret = rproc_attach_recovery(rproc);
+               return rproc_attach_recovery(rproc);
        else
-               ret = rproc_boot_recovery(rproc);
-
-unlock_mutex:
-       mutex_unlock(&rproc->lock);
-       return ret;
+               return rproc_boot_recovery(rproc);
 }
 
 /**
@@ -2057,7 +2050,7 @@ int rproc_detach(struct rproc *rproc)
                return ret;
        }
 
-       if (rproc->state != RPROC_ATTACHED) {
+       if (rproc->state != RPROC_ATTACHED && rproc->state != RPROC_CRASHED) {
                ret = -EINVAL;
                goto out;
        }
-- 
2.34.1