[PATCH 2/6] remoteproc: Add support for detach-only during shutdown
From: Suman Anna <hidden>
Date: 2021-05-22 00:03:50
Also in:
linux-remoteproc, lkml
Subsystem:
remote processor (remoteproc) subsystem, the rest · Maintainers:
Bjorn Andersson, Mathieu Poirier, Linus Torvalds
The remoteproc core has support for both stopping and detaching a remote processor that was attached to previously, through both the remoteproc sysfs and cdev interfaces. The rproc_shutdown() though unconditionally only uses the stop functionality at present. This may not be the default desired functionality for all the remoteproc platform drivers. Introduce a new rproc state flag 'detach_on_shutdown' that individual remoteproc drivers can set to only allow detach in rproc_shutdown() that would have been invoked when the driver is uninstalled, so that remote processor continues to run undisturbed even after the driver removal. Signed-off-by: Suman Anna <redacted> --- drivers/remoteproc/remoteproc_cdev.c | 7 +++++++ drivers/remoteproc/remoteproc_core.c | 5 ++++- drivers/remoteproc/remoteproc_sysfs.c | 6 ++++++ include/linux/remoteproc.h | 3 +++ 4 files changed, 20 insertions(+), 1 deletion(-)
diff --git a/drivers/remoteproc/remoteproc_cdev.c b/drivers/remoteproc/remoteproc_cdev.c
index 0b8a84c04f76..473467711a09 100644
--- a/drivers/remoteproc/remoteproc_cdev.c
+++ b/drivers/remoteproc/remoteproc_cdev.c@@ -42,6 +42,13 @@ static ssize_t rproc_cdev_write(struct file *filp, const char __user *buf, size_ rproc->state != RPROC_ATTACHED) return -EINVAL; + if (rproc->state == RPROC_ATTACHED && + rproc->detach_on_shutdown) { + dev_err(&rproc->dev, + "stop not supported for this rproc, use detach\n"); + return -EINVAL; + } + rproc_shutdown(rproc); } else if (!strncmp(cmd, "detach", len)) { if (rproc->state != RPROC_ATTACHED)
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 6019f46001c8..e8ab3eb41f00 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c@@ -2074,7 +2074,10 @@ void rproc_shutdown(struct rproc *rproc) if (!atomic_dec_and_test(&rproc->power)) goto out; - ret = rproc_stop(rproc, false); + if (rproc->detach_on_shutdown && rproc->state == RPROC_ATTACHED) + ret = __rproc_detach(rproc); + else + ret = rproc_stop(rproc, false); if (ret) { atomic_inc(&rproc->power); goto out;
diff --git a/drivers/remoteproc/remoteproc_sysfs.c b/drivers/remoteproc/remoteproc_sysfs.c
index ea8b89f97d7b..1785fbcb1075 100644
--- a/drivers/remoteproc/remoteproc_sysfs.c
+++ b/drivers/remoteproc/remoteproc_sysfs.c@@ -206,6 +206,12 @@ static ssize_t state_store(struct device *dev, rproc->state != RPROC_ATTACHED) return -EINVAL; + if (rproc->state == RPROC_ATTACHED && + rproc->detach_on_shutdown) { + dev_err(&rproc->dev, "stop not supported for this rproc, use detach\n"); + return -EINVAL; + } + rproc_shutdown(rproc); } else if (sysfs_streq(buf, "detach")) { if (rproc->state != RPROC_ATTACHED)
diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index 42a1f30e33a7..35ef921676a1 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h@@ -530,6 +530,8 @@ struct rproc_dump_segment { * @elf_machine: firmware ELF machine * @cdev: character device of the rproc * @cdev_put_on_release: flag to indicate if remoteproc should be shutdown on @char_dev release + * @detach_on_shutdown: flag to indicate if remoteproc cannot be shutdown in + * attached state and _only_ support detach */ struct rproc { struct list_head node;
@@ -569,6 +571,7 @@ struct rproc { u16 elf_machine; struct cdev cdev; bool cdev_put_on_release; + bool detach_on_shutdown; }; /**
--
2.30.1
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