RE: [PATCH v3 2/2] PM / devfreq: Add devfreq driver for interconnect bandwidth voting
From: MyungJoo Ham <myungjoo.ham@samsung.com>
Date: 2018-08-02 10:13:49
Also in:
linux-devicetree, lkml
This driver registers itself as a devfreq device that allows devfreq governors to make bandwidth votes for an interconnect path. This allows applying various policies for different interconnect paths using devfreq governors.
First of all, the name, "devfreq_icbw", is not appropriate for a devfreq device driver. It confuses; it looks like a part of the framework itself.
quoted hunk ↗ jump to hunk
diff --git a/drivers/devfreq/devfreq_icbw.c b/drivers/devfreq/devfreq_icbw.c new file mode 100644 index 0000000..231fb21 --- /dev/null +++ b/drivers/devfreq/devfreq_icbw.c@@ -0,0 +1,116 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2013-2014, 2018, The Linux Foundation. All rights reserved. + */ + +#define pr_fmt(fmt) "icbw: " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/mutex.h> +#include <linux/devfreq.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/interconnect.h>
Where can I find this file?
+
+struct dev_data {
+ struct icc_path *path;
+ u32 cur_ab;
+ u32 cur_pb;
+ unsigned long gov_ab;
+ struct devfreq *df;
+ struct devfreq_dev_profile dp;
+};
+
+static int icbw_target(struct device *dev, unsigned long *freq, u32 flags)
+{
+ struct dev_data *d = dev_get_drvdata(dev);
+ int ret;
+ u32 new_pb = *freq, new_ab = d->gov_ab;
+
+ if (d->cur_pb == new_pb && d->cur_ab == new_ab)
+ return 0;
+
+ dev_dbg(dev, "BW KBps: AB: %u PB: %u\n", new_ab, new_pb);
+
+ ret = icc_set(d->path, new_ab, new_pb);I'm not sure if icc_set is available. Cheers, MyungJoo