[PATCH 5.18 019/102] cpufreq: amd-pstate: Add resume and suspend callbacks

Greg Kroah-Hartman
2022-07-05T12:31:09Z

From: Jinzhou Su <Jinzhou.Su@amd.com>

commit b376471fb47d4905e72fe73e9eeed228f8f2f230 upstream.

When system resumes from S3, the CPPC enable register will be
cleared and reset to 0.

So enable the CPPC interface by writing 1 to this register on
system resume and disable it during system suspend.

Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com>
Signed-off-by: Jinzhou Su <Jinzhou.Su@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
[ rjw: Subject and changelog edits ]
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/cpufreq/amd-pstate.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)

--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -566,6 +566,28 @@ static int amd_pstate_cpu_exit(struct cp
return 0;
}

+static int amd_pstate_cpu_resume(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ ret = amd_pstate_enable(true);
+ if (ret)
+ pr_err("failed to enable amd-pstate during resume, return %d\n", ret);
+
+ return ret;
+}
+
+static int amd_pstate_cpu_suspend(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ ret = amd_pstate_enable(false);
+ if (ret)
+ pr_err("failed to disable amd-pstate during suspend, return %d\n", ret);
+
+ return ret;
+}
+
/* Sysfs attributes */

/*
@@ -636,6 +658,8 @@ static struct cpufreq_driver amd_pstate_
.target = amd_pstate_target,
.init = amd_pstate_cpu_init,
.exit = amd_pstate_cpu_exit,
+ .suspend = amd_pstate_cpu_suspend,
+ .resume = amd_pstate_cpu_resume,
.set_boost = amd_pstate_set_boost,
.name = "amd-pstate",
.attr = amd_pstate_attr,