[Intel-gfx] [PATCH v4 24/25] drm/i915: Add sysfs interface to know the HW requested frequency

[Sagar Arun Kamble]

With SLPC, user can read this value to know SLPC requested frequency.

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
---
 drivers/gpu/drm/i915/i915_sysfs.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_sysfs.c b/drivers/gpu/drm/i915/i915_sysfs.c
index ab161ca..7bff742 100644
--- a/drivers/gpu/drm/i915/i915_sysfs.c
+++ b/drivers/gpu/drm/i915/i915_sysfs.c
@@ -307,6 +307,32 @@ static ssize_t gt_cur_freq_mhz_show(struct device *kdev,
 				       dev_priv->rps.cur_freq));
 }
 
+static ssize_t gt_req_freq_mhz_show(struct device *kdev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
+	u32 reqf;
+
+	if (!intel_runtime_pm_get_if_in_use(dev_priv))
+		return -ENODEV;
+
+	reqf = I915_READ(GEN6_RPNSWREQ);
+	intel_runtime_pm_put(dev_priv);
+
+	if (IS_GEN9(dev_priv))
+		reqf >>= 23;
+	else {
+		reqf &= ~GEN6_TURBO_DISABLE;
+		if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
+			reqf >>= 24;
+		else
+			reqf >>= 25;
+	}
+	reqf = intel_gpu_freq(dev_priv, reqf);
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", reqf);
+}
+
 static ssize_t gt_boost_freq_mhz_show(struct device *kdev, struct device_attribute *attr, char *buf)
 {
 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
@@ -481,6 +507,7 @@ static ssize_t gt_min_freq_mhz_store(struct device *kdev,
 
 static DEVICE_ATTR(gt_act_freq_mhz, S_IRUGO, gt_act_freq_mhz_show, NULL);
 static DEVICE_ATTR(gt_cur_freq_mhz, S_IRUGO, gt_cur_freq_mhz_show, NULL);
+static DEVICE_ATTR(gt_req_freq_mhz, S_IRUGO, gt_req_freq_mhz_show, NULL);
 static DEVICE_ATTR(gt_boost_freq_mhz, S_IRUGO, gt_boost_freq_mhz_show, gt_boost_freq_mhz_store);
 static DEVICE_ATTR(gt_max_freq_mhz, S_IRUGO | S_IWUSR, gt_max_freq_mhz_show, gt_max_freq_mhz_store);
 static DEVICE_ATTR(gt_min_freq_mhz, S_IRUGO | S_IWUSR, gt_min_freq_mhz_show, gt_min_freq_mhz_store);
@@ -513,6 +540,7 @@ static ssize_t gt_rp_mhz_show(struct device *kdev, struct device_attribute *attr
 static const struct attribute *gen6_attrs[] = {
 	&dev_attr_gt_act_freq_mhz.attr,
 	&dev_attr_gt_cur_freq_mhz.attr,
+	&dev_attr_gt_req_freq_mhz.attr,
 	&dev_attr_gt_boost_freq_mhz.attr,
 	&dev_attr_gt_max_freq_mhz.attr,
 	&dev_attr_gt_min_freq_mhz.attr,
-- 
1.9.1