Re: [PATCH v5 07/19] remoteproc: Add new get_loaded_rsc_table() to rproc_ops

Add a new get_loaded_rsc_table() operation in order to support
scenarios where the remoteproc core has booted a remote processor
and detaches from it.  When re-attaching to the remote processor,
the core needs to know where the resource table has been placed
in memory.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
New for V5:
- Added function rproc_set_loaded_rsc_table() to keep rproc_attach() clean.
- Setting ->cached_table, ->table_ptr and ->table_sz in the remoteproc core
  rather than the platform drivers.
---
 drivers/remoteproc/remoteproc_core.c     | 35 ++++++++++++++++++++++++
 drivers/remoteproc/remoteproc_internal.h | 10 +++++++
 include/linux/remoteproc.h               |  6 +++-
 3 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index e6606d10a4c8..741bc20de437 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c

@@ -1537,6 +1537,35 @@ static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
 	return ret;
 }
 
+static int rproc_set_loaded_rsc_table(struct rproc *rproc)
+{
+	struct resource_table *table_ptr;
+	struct device *dev = &rproc->dev;
+	size_t table_sz;
+	int ret;
+
+	table_ptr = rproc_get_loaded_rsc_table(rproc, &table_sz);
+	if (IS_ERR_OR_NULL(table_ptr)) {
+		if (!table_ptr)
+			ret = -EINVAL;

+		else
+			ret = PTR_ERR(table_ptr);
+
+		dev_err(dev, "can't load resource table: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * The resource table is already loaded in device memory, no need
+	 * to work with a cached table.
+	 */
+	rproc->cached_table = NULL;
+	rproc->table_ptr = table_ptr;
+	rproc->table_sz = table_sz;
+
+	return 0;
+}
+
 /*
  * Attach to remote processor - similar to rproc_fw_boot() but without
  * the steps that deal with the firmware image.

@@ -1556,6 +1585,12 @@ static int rproc_attach(struct rproc *rproc)
 		return ret;
 	}
 
+	ret = rproc_set_loaded_rsc_table(rproc);
+	if (ret) {
+		dev_err(dev, "can't load resource table: %d\n", ret);
+		goto disable_iommu;
+	}
+
 	/* reset max_notifyid */
 	rproc->max_notifyid = -1;
 

diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h
index c34002888d2c..4f73aac7e60d 100644
--- a/drivers/remoteproc/remoteproc_internal.h
+++ b/drivers/remoteproc/remoteproc_internal.h

@@ -177,6 +177,16 @@ struct resource_table *rproc_find_loaded_rsc_table(struct rproc *rproc,
 	return NULL;
 }
 
+static inline
+struct resource_table *rproc_get_loaded_rsc_table(struct rproc *rproc,
+						  size_t *size)
+{
+	if (rproc->ops->get_loaded_rsc_table)
+		return rproc->ops->get_loaded_rsc_table(rproc, size);
+
+	return NULL;
+}
+
 static inline
 bool rproc_u64_fit_in_size_t(u64 val)
 {

diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index 6b0a0ed30a03..51538a7d120d 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h

@@ -368,7 +368,9 @@ enum rsc_handling_status {
  * RSC_HANDLED if resource was handled, RSC_IGNORED if not handled and a
  * negative value on error
  * @load_rsc_table:	load resource table from firmware image
- * @find_loaded_rsc_table: find the loaded resouce table
+ * @find_loaded_rsc_table: find the loaded resource table from firmware image
+ * @get_loaded_rsc_table: get resource table installed in memory
+ *			  by external entity
  * @load:		load firmware to memory, where the remote processor
  *			expects to find it
  * @sanity_check:	sanity check the fw image

@@ -390,6 +392,8 @@ struct rproc_ops {
 			  int offset, int avail);
 	struct resource_table *(*find_loaded_rsc_table)(
 				struct rproc *rproc, const struct firmware *fw);
+	struct resource_table *(*get_loaded_rsc_table)(
+				struct rproc *rproc, size_t *size);
 	int (*load)(struct rproc *rproc, const struct firmware *fw);
 	int (*sanity_check)(struct rproc *rproc, const struct firmware *fw);
 	u64 (*get_boot_addr)(struct rproc *rproc, const struct firmware *fw);