drm/i915: Add debugfs knobs for VLVCHV memory latency values

Allow tweaking the VLV/CHV memory latencies thorugh sysfs, like we do
for ILK+.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Clint Taylor <Clinton.A.Taylor@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 7d303e7..68a5e86 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -4203,8 +4203,15 @@ static const struct file_operations i915_displayport_test_type_fops = {
 static void wm_latency_show(struct seq_file *m, const uint16_t wm[8])
 {
        struct drm_device *dev = m->private;
-       int num_levels = ilk_wm_max_level(dev) + 1;
        int level;
+       int num_levels;
+
+       if (IS_CHERRYVIEW(dev))
+               num_levels = 3;
+       else if (IS_VALLEYVIEW(dev))
+               num_levels = 1;
+       else
+               num_levels = ilk_wm_max_level(dev) + 1;
 
        drm_modeset_lock_all(dev);
 
@@ -4213,9 +4220,9 @@ static void wm_latency_show(struct seq_file *m, const uint16_t wm[8])
 
                /*
                 * - WM1+ latency values in 0.5us units
-                * - latencies are in us on gen9
+                * - latencies are in us on gen9/vlv/chv
                 */
-               if (INTEL_INFO(dev)->gen >= 9)
+               if (INTEL_INFO(dev)->gen >= 9 || IS_VALLEYVIEW(dev))
                        latency *= 10;
                else if (level > 0)
                        latency *= 5;
@@ -4279,7 +4286,7 @@ static int pri_wm_latency_open(struct inode *inode, struct file *file)
 {
        struct drm_device *dev = inode->i_private;
 
-       if (HAS_GMCH_DISPLAY(dev))
+       if (INTEL_INFO(dev)->gen < 5)
                return -ENODEV;
 
        return single_open(file, pri_wm_latency_show, dev);
@@ -4311,11 +4318,18 @@ static ssize_t wm_latency_write(struct file *file, const char __user *ubuf,
        struct seq_file *m = file->private_data;
        struct drm_device *dev = m->private;
        uint16_t new[8] = { 0 };
-       int num_levels = ilk_wm_max_level(dev) + 1;
+       int num_levels;
        int level;
        int ret;
        char tmp[32];
 
+       if (IS_CHERRYVIEW(dev))
+               num_levels = 3;
+       else if (IS_VALLEYVIEW(dev))
+               num_levels = 1;
+       else
+               num_levels = ilk_wm_max_level(dev) + 1;
+
        if (len >= sizeof(tmp))
                return -EINVAL;