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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/macintosh/windfarm_cpufreq_clamp.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/macintosh/windfarm_cpufreq_clamp.c')
-rw-r--r--drivers/macintosh/windfarm_cpufreq_clamp.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/drivers/macintosh/windfarm_cpufreq_clamp.c b/drivers/macintosh/windfarm_cpufreq_clamp.c
new file mode 100644
index 0000000000..28d18ef22b
--- /dev/null
+++ b/drivers/macintosh/windfarm_cpufreq_clamp.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/pm_qos.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/wait.h>
+#include <linux/cpu.h>
+#include <linux/cpufreq.h>
+
+#include "windfarm.h"
+
+#define VERSION "0.3"
+
+static int clamped;
+static struct wf_control *clamp_control;
+static struct freq_qos_request qos_req;
+static unsigned int min_freq, max_freq;
+
+static int clamp_set(struct wf_control *ct, s32 value)
+{
+ unsigned int freq;
+
+ if (value) {
+ freq = min_freq;
+ printk(KERN_INFO "windfarm: Clamping CPU frequency to "
+ "minimum !\n");
+ } else {
+ freq = max_freq;
+ printk(KERN_INFO "windfarm: CPU frequency unclamped !\n");
+ }
+ clamped = value;
+
+ return freq_qos_update_request(&qos_req, freq);
+}
+
+static int clamp_get(struct wf_control *ct, s32 *value)
+{
+ *value = clamped;
+ return 0;
+}
+
+static s32 clamp_min(struct wf_control *ct)
+{
+ return 0;
+}
+
+static s32 clamp_max(struct wf_control *ct)
+{
+ return 1;
+}
+
+static const struct wf_control_ops clamp_ops = {
+ .set_value = clamp_set,
+ .get_value = clamp_get,
+ .get_min = clamp_min,
+ .get_max = clamp_max,
+ .owner = THIS_MODULE,
+};
+
+static int __init wf_cpufreq_clamp_init(void)
+{
+ struct cpufreq_policy *policy;
+ struct wf_control *clamp;
+ struct device *dev;
+ int ret;
+
+ policy = cpufreq_cpu_get(0);
+ if (!policy) {
+ pr_warn("%s: cpufreq policy not found cpu0\n", __func__);
+ return -EPROBE_DEFER;
+ }
+
+ min_freq = policy->cpuinfo.min_freq;
+ max_freq = policy->cpuinfo.max_freq;
+
+ ret = freq_qos_add_request(&policy->constraints, &qos_req, FREQ_QOS_MAX,
+ max_freq);
+
+ cpufreq_cpu_put(policy);
+
+ if (ret < 0) {
+ pr_err("%s: Failed to add freq constraint (%d)\n", __func__,
+ ret);
+ return ret;
+ }
+
+ dev = get_cpu_device(0);
+ if (unlikely(!dev)) {
+ pr_warn("%s: No cpu device for cpu0\n", __func__);
+ ret = -ENODEV;
+ goto fail;
+ }
+
+ clamp = kmalloc(sizeof(struct wf_control), GFP_KERNEL);
+ if (clamp == NULL) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ clamp->ops = &clamp_ops;
+ clamp->name = "cpufreq-clamp";
+ ret = wf_register_control(clamp);
+ if (ret)
+ goto free;
+
+ clamp_control = clamp;
+ return 0;
+
+ free:
+ kfree(clamp);
+ fail:
+ freq_qos_remove_request(&qos_req);
+ return ret;
+}
+
+static void __exit wf_cpufreq_clamp_exit(void)
+{
+ if (clamp_control) {
+ wf_unregister_control(clamp_control);
+ freq_qos_remove_request(&qos_req);
+ }
+}
+
+
+module_init(wf_cpufreq_clamp_init);
+module_exit(wf_cpufreq_clamp_exit);
+
+MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
+MODULE_DESCRIPTION("CPU frequency clamp for PowerMacs thermal control");
+MODULE_LICENSE("GPL");
+