interconnect: Add bulk API helpers

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@chromium.org>
Suggested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20200729123439.9961-1-georgi.djakov@linaro.org
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>

diff --git a/drivers/interconnect/Makefile b/drivers/interconnect/Makefile
index 4825c287ca13c8dce2d2a117e39e50da763ed4fd..d203520b0a5671ac471e38801cad7d3c4a6f2bff 100644 (file)
--- 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 (file)
index 0000000..73e2c8d
--- /dev/null
+++ b/drivers/interconnect/bulk.c
@@ -0,0 +1,117 @@
+// 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 negative errno 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);
+                       if (ret != -EPROBE_DEFER)
+                               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 negative errno 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 negative errno 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 3a63d98613fce983b685341030b69f06b13787d4..f2dd2fc8d3cdf5153ac4fda7851b6d4ad00b78db 100644 (file)
--- 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,