drm/amd/pm: add zero RPM OD setting support for SMU13

Whilst we have support for setting fan curves there is no support for
disabling the zero RPM feature. Since the relevant bits are already
present in the OverDriveTable, hook them up to a sysctl setting so users
can influence this behaviour.

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3489
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Signed-off-by: Wolfgang Müller <wolf@oriole.systems>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/pm/amdgpu_pm.c b/drivers/gpu/drm/amd/pm/amdgpu_pm.c
index ea940773353c..cb96f1f8ca8d 100644
--- a/drivers/gpu/drm/amd/pm/amdgpu_pm.c
+++ b/drivers/gpu/drm/amd/pm/amdgpu_pm.c
@@ -4109,6 +4109,60 @@ static umode_t fan_minimum_pwm_visible(struct amdgpu_device *adev)
 	return umode;
 }
 
+/**
+ * DOC: fan_zero_rpm_enable
+ *
+ * The amdgpu driver provides a sysfs API for checking and adjusting the
+ * zero RPM feature.
+ *
+ * Reading back the file shows you the current setting and the permitted
+ * ranges if changable.
+ *
+ * Writing an integer to the file, change the setting accordingly.
+ *
+ * When you have finished the editing, write "c" (commit) to the file to commit
+ * your changes.
+ *
+ * If you want to reset to the default value, write "r" (reset) to the file to
+ * reset them.
+ */
+static ssize_t fan_zero_rpm_enable_show(struct kobject *kobj,
+					   struct kobj_attribute *attr,
+					   char *buf)
+{
+	struct od_kobj *container = container_of(kobj, struct od_kobj, kobj);
+	struct amdgpu_device *adev = (struct amdgpu_device *)container->priv;
+
+	return (ssize_t)amdgpu_retrieve_od_settings(adev, OD_FAN_ZERO_RPM_ENABLE, buf);
+}
+
+static ssize_t fan_zero_rpm_enable_store(struct kobject *kobj,
+					    struct kobj_attribute *attr,
+					    const char *buf,
+					    size_t count)
+{
+	struct od_kobj *container = container_of(kobj, struct od_kobj, kobj);
+	struct amdgpu_device *adev = (struct amdgpu_device *)container->priv;
+
+	return (ssize_t)amdgpu_distribute_custom_od_settings(adev,
+							     PP_OD_EDIT_FAN_ZERO_RPM_ENABLE,
+							     buf,
+							     count);
+}
+
+static umode_t fan_zero_rpm_enable_visible(struct amdgpu_device *adev)
+{
+	umode_t umode = 0000;
+
+	if (adev->pm.od_feature_mask & OD_OPS_SUPPORT_FAN_ZERO_RPM_ENABLE_RETRIEVE)
+		umode |= S_IRUSR | S_IRGRP | S_IROTH;
+
+	if (adev->pm.od_feature_mask & OD_OPS_SUPPORT_FAN_ZERO_RPM_ENABLE_SET)
+		umode |= S_IWUSR;
+
+	return umode;
+}
+
 static struct od_feature_set amdgpu_od_set = {
 	.containers = {
 		[0] = {
@@ -4154,6 +4208,14 @@ static struct od_feature_set amdgpu_od_set = {
 						.store = fan_minimum_pwm_store,
 					},
 				},
+				[5] = {
+					.name = "fan_zero_rpm_enable",
+					.ops = {
+						.is_visible = fan_zero_rpm_enable_visible,
+						.show = fan_zero_rpm_enable_show,
+						.store = fan_zero_rpm_enable_store,
+					},
+				},
 			},
 		},
 	},