[PATCH 1/2] remoteproc: Add prepare and unprepare ops

[Suman Anna]

From: Loic Pallardy <loic.pallardy@xxxxxx>

On some SoC architecture, it is needed to enable HW like
clock, bus, regulator, memory region... before loading
co-processor firmware.

This patch introduces prepare and unprepare ops to execute
platform specific function before firmware loading and after
stop execution.

Signed-off-by: Loic Pallardy <loic.pallardy@xxxxxx>
Signed-off-by: Suman Anna <s-anna@xxxxxx>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
v1:
 - Make the direct ops into inline helper functions in line
   with the comments on the MCU sync series (v1 comments).
   No change in functionality.
 - Picked up the Reviewed-by tags
v0: https://patchwork.kernel.org/patch/11456383/

 drivers/remoteproc/remoteproc_core.c     | 15 ++++++++++++++-
 drivers/remoteproc/remoteproc_internal.h | 16 ++++++++++++++++
 include/linux/remoteproc.h               |  4 ++++
 3 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index d681eeb962b6..e38f627059ac 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -1394,12 +1394,19 @@ static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
 		return ret;
 	}
 
+	/* Prepare rproc for firmware loading if needed */
+	ret = rproc_prepare_device(rproc);
+	if (ret) {
+		dev_err(dev, "can't prepare rproc %s: %d\n", rproc->name, ret);
+		goto disable_iommu;
+	}
+
 	rproc->bootaddr = rproc_get_boot_addr(rproc, fw);
 
 	/* Load resource table, core dump segment list etc from the firmware */
 	ret = rproc_parse_fw(rproc, fw);
 	if (ret)
-		goto disable_iommu;
+		goto unprepare_rproc;
 
 	/* reset max_notifyid */
 	rproc->max_notifyid = -1;
@@ -1433,6 +1440,9 @@ static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
 	kfree(rproc->cached_table);
 	rproc->cached_table = NULL;
 	rproc->table_ptr = NULL;
+unprepare_rproc:
+	/* release HW resources if needed */
+	rproc_unprepare_device(rproc);
 disable_iommu:
 	rproc_disable_iommu(rproc);
 	return ret;
@@ -1838,6 +1848,9 @@ void rproc_shutdown(struct rproc *rproc)
 	/* clean up all acquired resources */
 	rproc_resource_cleanup(rproc);
 
+	/* release HW resources if needed */
+	rproc_unprepare_device(rproc);
+
 	rproc_disable_iommu(rproc);
 
 	/* Free the copy of the resource table */
diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h
index b389dc79da81..101e6be8d240 100644
--- a/drivers/remoteproc/remoteproc_internal.h
+++ b/drivers/remoteproc/remoteproc_internal.h
@@ -64,6 +64,22 @@ struct resource_table *rproc_elf_find_loaded_rsc_table(struct rproc *rproc,
 struct rproc_mem_entry *
 rproc_find_carveout_by_name(struct rproc *rproc, const char *name, ...);
 
+static inline int rproc_prepare_device(struct rproc *rproc)
+{
+	if (rproc->ops->prepare)
+		return rproc->ops->prepare(rproc);
+
+	return 0;
+}
+
+static inline int rproc_unprepare_device(struct rproc *rproc)
+{
+	if (rproc->ops->unprepare)
+		return rproc->ops->unprepare(rproc);
+
+	return 0;
+}
+
 static inline
 int rproc_fw_sanity_check(struct rproc *rproc, const struct firmware *fw)
 {
diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index 38607107b7cb..b8481ac969f1 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -355,6 +355,8 @@ enum rsc_handling_status {
 
 /**
  * struct rproc_ops - platform-specific device handlers
+ * @prepare:	prepare device for code loading
+ * @unprepare:	unprepare device after stop
  * @start:	power on the device and boot it
  * @stop:	power off the device
  * @kick:	kick a virtqueue (virtqueue id given as a parameter)
@@ -373,6 +375,8 @@ enum rsc_handling_status {
  *		panic at least the returned number of milliseconds
  */
 struct rproc_ops {
+	int (*prepare)(struct rproc *rproc);
+	int (*unprepare)(struct rproc *rproc);
 	int (*start)(struct rproc *rproc);
 	int (*stop)(struct rproc *rproc);
 	void (*kick)(struct rproc *rproc, int vqid);
-- 
2.26.0