drm/i915: Removed the read of RP_STATE_CAP from sysfs/debugfs functions

The frequency values(Rp0, Rp1, Rpn) reported by RP_STATE_CAP register
are stored, initially by the Driver, inside the dev_priv->rps structure.
Since these values are expected to remain same throughout, there is no real
need to read this register, on dynamic basis, from certain debugfs/sysfs
functions and the values can be instead retrieved from the dev_priv->rps
structure when needed.
For the i915_frequency_info debugfs interface, the frequency values from the
RP_STATE_CAP register only should be used, to indicate the actual Hw state,
since it is principally used for the debugging purpose.

v2: Reverted the changes in i915_frequency_info function, to continue report
    back the frequency values, as per the actual Hw state (Chris)

Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

2 files changed, 17 insertions, 54 deletions

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 843b471090f3..81e27d417130 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -4180,7 +4180,7 @@ i915_max_freq_set(void *data, u64 val)
 {
         struct drm_device *dev = data;
         struct drm_i915_private *dev_priv = dev->dev_private;
-        u32 rp_state_cap, hw_max, hw_min;
+        u32 hw_max, hw_min;
         int ret;
 
         if (INTEL_INFO(dev)->gen < 6)
@@ -4197,18 +4197,10 @@ i915_max_freq_set(void *data, u64 val)
         /*
          * Turbo will still be enabled, but won't go above the set value.
          */
-        if (IS_VALLEYVIEW(dev)) {
-                val = intel_freq_opcode(dev_priv, val);
+        val = intel_freq_opcode(dev_priv, val);
 
-                hw_max = dev_priv->rps.max_freq;
-                hw_min = dev_priv->rps.min_freq;
-        } else {
-                val = intel_freq_opcode(dev_priv, val);
-
-                rp_state_cap = I915_READ(GEN6_RP_STATE_CAP);
-                hw_max = dev_priv->rps.max_freq;
-                hw_min = (rp_state_cap >> 16) & 0xff;
-        }
+        hw_max = dev_priv->rps.max_freq;
+        hw_min = dev_priv->rps.min_freq;
 
         if (val < hw_min || val > hw_max || val < dev_priv->rps.min_freq_softlimit) {
                 mutex_unlock(&dev_priv->rps.hw_lock);
@@ -4255,7 +4247,7 @@ i915_min_freq_set(void *data, u64 val)
 {
         struct drm_device *dev = data;
         struct drm_i915_private *dev_priv = dev->dev_private;
-        u32 rp_state_cap, hw_max, hw_min;
+        u32 hw_max, hw_min;
         int ret;
 
         if (INTEL_INFO(dev)->gen < 6)
@@ -4272,18 +4264,10 @@ i915_min_freq_set(void *data, u64 val)
         /*
          * Turbo will still be enabled, but won't go below the set value.
          */
-        if (IS_VALLEYVIEW(dev)) {
-                val = intel_freq_opcode(dev_priv, val);
+        val = intel_freq_opcode(dev_priv, val);
 
-                hw_max = dev_priv->rps.max_freq;
-                hw_min = dev_priv->rps.min_freq;
-        } else {
-                val = intel_freq_opcode(dev_priv, val);
-
-                rp_state_cap = I915_READ(GEN6_RP_STATE_CAP);
-                hw_max = dev_priv->rps.max_freq;
-                hw_min = (rp_state_cap >> 16) & 0xff;
-        }
+        hw_max = dev_priv->rps.max_freq;
+        hw_min = dev_priv->rps.min_freq;
 
         if (val < hw_min || val > hw_max || val > dev_priv->rps.max_freq_softlimit) {
                 mutex_unlock(&dev_priv->rps.hw_lock);
diff --git a/drivers/gpu/drm/i915/i915_sysfs.c b/drivers/gpu/drm/i915/i915_sysfs.c
index cdc9da001484..186ab95056b0 100644
--- a/drivers/gpu/drm/i915/i915_sysfs.c
+++ b/drivers/gpu/drm/i915/i915_sysfs.c
@@ -487,38 +487,17 @@ static ssize_t gt_rp_mhz_show(struct device *kdev, struct device_attribute *attr
         struct drm_minor *minor = dev_to_drm_minor(kdev);
         struct drm_device *dev = minor->dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
-        u32 val, rp_state_cap;
-        ssize_t ret;
-
-        ret = mutex_lock_interruptible(&dev->struct_mutex);
-        if (ret)
-                return ret;
-        intel_runtime_pm_get(dev_priv);
-        rp_state_cap = I915_READ(GEN6_RP_STATE_CAP);
-        intel_runtime_pm_put(dev_priv);
-        mutex_unlock(&dev->struct_mutex);
+        u32 val;
 
-        if (attr == &dev_attr_gt_RP0_freq_mhz) {
-                if (IS_VALLEYVIEW(dev))
-                        val = intel_gpu_freq(dev_priv, dev_priv->rps.rp0_freq);
-                else
-                        val = intel_gpu_freq(dev_priv,
-                                             ((rp_state_cap & 0x0000ff) >> 0));
-        } else if (attr == &dev_attr_gt_RP1_freq_mhz) {
-                if (IS_VALLEYVIEW(dev))
-                        val = intel_gpu_freq(dev_priv, dev_priv->rps.rp1_freq);
-                else
-                        val = intel_gpu_freq(dev_priv,
-                                             ((rp_state_cap & 0x00ff00) >> 8));
-        } else if (attr == &dev_attr_gt_RPn_freq_mhz) {
-                if (IS_VALLEYVIEW(dev))
-                        val = intel_gpu_freq(dev_priv, dev_priv->rps.min_freq);
-                else
-                        val = intel_gpu_freq(dev_priv,
-                                             ((rp_state_cap & 0xff0000) >> 16));
-        } else {
+        if (attr == &dev_attr_gt_RP0_freq_mhz)
+                val = intel_gpu_freq(dev_priv, dev_priv->rps.rp0_freq);
+        else if (attr == &dev_attr_gt_RP1_freq_mhz)
+                val = intel_gpu_freq(dev_priv, dev_priv->rps.rp1_freq);
+        else if (attr == &dev_attr_gt_RPn_freq_mhz)
+                val = intel_gpu_freq(dev_priv, dev_priv->rps.min_freq);
+        else
                 BUG();
-        }
+
         return snprintf(buf, PAGE_SIZE, "%d\n", val);
 }