Commit d3962a39 authored by Mathieu Poirier's avatar Mathieu Poirier Committed by Bjorn Andersson
Browse files

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: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: default avatarArnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20210312162453.1234145-11-mathieu.poirier@linaro.org


Signed-off-by: default avatarBjorn Andersson <bjorn.andersson@linaro.org>
parent 6070203f

drivers/remoteproc/remoteproc_core.c

+57 −1
Original line number Diff line number Diff line
@@ -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;
@@ -1954,6 +1954,62 @@ void rproc_shutdown(struct rproc *rproc) 
}

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

include/linux/remoteproc.h

+1 −0
Original line number Diff line number Diff line
@@ -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);