[PATCH] interconnect: Add bulk API helpers

From: Georgi Djakov
Date: Thu May 28 2020 - 12:25:50 EST


There are drivers which just need to get multiple interconnect paths,
request some predefined amounts of bandwidth and then just toggle the
paths between enabled/disabled state.

The aim of this patch is simplify the above and to allow drivers to put
all the path names and bandwidth data into a single static icc_bulk_data
table and call the icc_bulk_* functions on that table in order to scale
all the interconnect paths in parallel.

Suggested-by: Evan Green <evgreen@xxxxxxxxxxxx>
Suggested-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Signed-off-by: Georgi Djakov <georgi.djakov@xxxxxxxxxx>
---
drivers/interconnect/Makefile | 2 +-
drivers/interconnect/bulk.c | 119 ++++++++++++++++++++++++++++++++++
include/linux/interconnect.h | 22 +++++++
3 files changed, 142 insertions(+), 1 deletion(-)
create mode 100644 drivers/interconnect/bulk.c

diff --git a/drivers/interconnect/Makefile b/drivers/interconnect/Makefile
index 4825c287ca13..d203520b0a56 100644
--- a/drivers/interconnect/Makefile
+++ b/drivers/interconnect/Makefile
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0

CFLAGS_core.o := -I$(src)
-icc-core-objs := core.o
+icc-core-objs := core.o bulk.o

obj-$(CONFIG_INTERCONNECT) += icc-core.o
obj-$(CONFIG_INTERCONNECT_IMX) += imx/
diff --git a/drivers/interconnect/bulk.c b/drivers/interconnect/bulk.c
new file mode 100644
index 000000000000..9bd418594665
--- /dev/null
+++ b/drivers/interconnect/bulk.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/interconnect-provider.h>
+#include <linux/device.h>
+#include <linux/export.h>
+
+/**
+ * of_icc_bulk_get - get interconnect paths
+ * @dev: the device requesting the path
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the table with the paths we want to get
+ *
+ * Returns 0 on success or -EERROR otherwise.
+ */
+int __must_check of_icc_bulk_get(struct device *dev, int num_paths,
+ struct icc_bulk_data *paths)
+{
+ int ret, i;
+
+ for (i = 0; i < num_paths; i++) {
+ paths[i].path = of_icc_get(dev, paths[i].name);
+ if (IS_ERR(paths[i].path)) {
+ ret = PTR_ERR(paths[i].path);
+ dev_err(dev, "of_icc_get() failed on path %s (%d)\n",
+ paths[i].name, ret);
+ paths[i].path = NULL;
+ goto err;
+ }
+ }
+
+ return 0;
+
+err:
+ icc_bulk_put(i, paths);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_icc_bulk_get);
+
+/**
+ * icc_bulk_put - put a list of interconnect paths
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the icc_bulk_data table with the paths being put
+ */
+void icc_bulk_put(int num_paths, struct icc_bulk_data *paths)
+{
+ while (--num_paths >= 0) {
+ icc_put(paths[num_paths].path);
+ paths[num_paths].path = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(icc_bulk_put);
+
+/**
+ * icc_bulk_set - set bandwidth to a set of paths
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the icc_bulk_data table containing the paths and bandwidth
+ *
+ * Returns 0 on success or -EERROR otherwise.
+ */
+int icc_bulk_set_bw(int num_paths, const struct icc_bulk_data *paths)
+{
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < num_paths; i++) {
+ ret = icc_set_bw(paths[i].path, paths[i].avg_bw,
+ paths[i].peak_bw);
+ if (ret) {
+ pr_err("icc_set_bw() failed on path %s (%d)\n",
+ paths[i].name, ret);
+ return ret;
+ }
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(icc_bulk_set_bw);
+
+/**
+ * icc_bulk_enable - enable a previously disabled set of paths
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the icc_bulk_data table containing the paths and bandwidth
+ *
+ * Returns 0 on success or -EERROR otherwise.
+ */
+int icc_bulk_enable(int num_paths, const struct icc_bulk_data *paths)
+{
+ int ret, i;
+
+ for (i = 0; i < num_paths; i++) {
+ ret = icc_enable(paths[i].path);
+ if (ret) {
+ pr_err("icc_enable() failed on path %s (%d)\n",
+ paths[i].name, ret);
+ goto err;
+ }
+ }
+
+ return 0;
+
+err:
+ icc_bulk_disable(i, paths);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(icc_bulk_enable);
+
+/**
+ * icc_bulk_disable - disable a set of interconnect paths
+ * @num_paths: the number of icc_bulk_data
+ * @paths: the icc_bulk_data table containing the paths and bandwidth
+ */
+void icc_bulk_disable(int num_paths, const struct icc_bulk_data *paths)
+{
+ while (--num_paths >= 0)
+ icc_disable(paths[num_paths].path);
+}
+EXPORT_SYMBOL_GPL(icc_bulk_disable);
diff --git a/include/linux/interconnect.h b/include/linux/interconnect.h
index d8c29049f066..7cf022176209 100644
--- a/include/linux/interconnect.h
+++ b/include/linux/interconnect.h
@@ -23,6 +23,28 @@
struct icc_path;
struct device;

+/**
+ * struct icc_bulk_data - Data used for bulk icc operations.
+ *
+ * @path: reference to the interconnect path (internal use)
+ * @name: the name from the "interconnect-names" DT property
+ * @avg_bw: average bandwidth in icc units
+ * @peak_bw: peak bandwidth in icc units
+ */
+struct icc_bulk_data {
+ struct icc_path *path;
+ const char *name;
+ u32 avg_bw;
+ u32 peak_bw;
+};
+
+int __must_check of_icc_bulk_get(struct device *dev, int num_paths,
+ struct icc_bulk_data *paths);
+void icc_bulk_put(int num_paths, struct icc_bulk_data *paths);
+int icc_bulk_set_bw(int num_paths, const struct icc_bulk_data *paths);
+int icc_bulk_enable(int num_paths, const struct icc_bulk_data *paths);
+void icc_bulk_disable(int num_paths, const struct icc_bulk_data *paths);
+
#if IS_ENABLED(CONFIG_INTERCONNECT)

struct icc_path *icc_get(struct device *dev, const int src_id,