diff options
| author | Mathieu Poirier <mathieu.poirier@linaro.org> | 2021-03-12 09:24:46 -0700 |
|---|---|---|
| committer | Bjorn Andersson <bjorn.andersson@linaro.org> | 2021-03-18 07:55:47 -0500 |
| commit | d3962a397885518a85d2dc6b0c51e6594f71c30f (patch) | |
| tree | 4e3b259b7e77083b992c10133800c878e0c76826 | |
| parent | 6070203fe43335a02b7fd103bae582095411adc5 (diff) | |
remoteproc: Introduce function rproc_detach()
Introduce function rproc_detach() to enable the remoteproc
core to release the resources associated with a remote processor
without stopping its operation.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20210312162453.1234145-11-mathieu.poirier@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
| -rw-r--r-- | drivers/remoteproc/remoteproc_core.c | 58 | ||||
| -rw-r--r-- | include/linux/remoteproc.h | 1 |
2 files changed, 58 insertions, 1 deletions
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index 23e9040386c2..78a36a3723ec 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -1715,7 +1715,7 @@ static int rproc_stop(struct rproc *rproc, bool crashed) /* * __rproc_detach(): Does the opposite of __rproc_attach() */ -static int __maybe_unused __rproc_detach(struct rproc *rproc) +static int __rproc_detach(struct rproc *rproc) { struct device *dev = &rproc->dev; int ret; @@ -1955,6 +1955,62 @@ out: EXPORT_SYMBOL(rproc_shutdown); /** + * rproc_detach() - Detach the remote processor from the + * remoteproc core + * + * @rproc: the remote processor + * + * Detach a remote processor (previously attached to with rproc_attach()). + * + * In case @rproc is still being used by an additional user(s), then + * this function will just decrement the power refcount and exit, + * without disconnecting the device. + * + * Function rproc_detach() calls __rproc_detach() in order to let a remote + * processor know that services provided by the application processor are + * no longer available. From there it should be possible to remove the + * platform driver and even power cycle the application processor (if the HW + * supports it) without needing to switch off the remote processor. + */ +int rproc_detach(struct rproc *rproc) +{ + struct device *dev = &rproc->dev; + int ret; + + ret = mutex_lock_interruptible(&rproc->lock); + if (ret) { + dev_err(dev, "can't lock rproc %s: %d\n", rproc->name, ret); + return ret; + } + + /* if the remote proc is still needed, bail out */ + if (!atomic_dec_and_test(&rproc->power)) { + ret = 0; + goto out; + } + + ret = __rproc_detach(rproc); + if (ret) { + atomic_inc(&rproc->power); + goto out; + } + + /* clean up all acquired resources */ + rproc_resource_cleanup(rproc); + + /* release HW resources if needed */ + rproc_unprepare_device(rproc); + + rproc_disable_iommu(rproc); + + rproc->table_ptr = NULL; +out: + mutex_unlock(&rproc->lock); + return ret; +} +EXPORT_SYMBOL(rproc_detach); + +/** * rproc_get_by_phandle() - find a remote processor by phandle * @phandle: phandle to the rproc * diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h index 2f1f0fbc3994..fc2cca600423 100644 --- a/include/linux/remoteproc.h +++ b/include/linux/remoteproc.h @@ -664,6 +664,7 @@ rproc_of_resm_mem_entry_init(struct device *dev, u32 of_resm_idx, size_t len, int rproc_boot(struct rproc *rproc); void rproc_shutdown(struct rproc *rproc); +int rproc_detach(struct rproc *rproc); int rproc_set_firmware(struct rproc *rproc, const char *fw_name); void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type); void rproc_coredump_using_sections(struct rproc *rproc); |