drm/i915: Print the watermark latencies during init
Seeing the watermark latency values in dmesg might help sometimes.
v2: Use DRM_ERROR() when expected latency values are missing
Note: We might hit the DRM_ERROR added in this patch and apparently
there's not much we can do about that. But I think it'd be interesting
to figure out whether that actually happens in the real world, so I
didn't apply a s/DRM_ERROR/DRM_DEBUG_KMS/ bikeshed while applying.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Add note about new error dmesg output.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 936c162..8358d73 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2409,6 +2409,39 @@
wm[3] *= 2;
}
+static void intel_print_wm_latency(struct drm_device *dev,
+ const char *name,
+ const uint16_t wm[5])
+{
+ int level, max_level;
+
+ /* how many WM levels are we expecting */
+ if (IS_HASWELL(dev))
+ max_level = 4;
+ else if (INTEL_INFO(dev)->gen >= 6)
+ max_level = 3;
+ else
+ max_level = 2;
+
+ for (level = 0; level <= max_level; level++) {
+ unsigned int latency = wm[level];
+
+ if (latency == 0) {
+ DRM_ERROR("%s WM%d latency not provided\n",
+ name, level);
+ continue;
+ }
+
+ /* WM1+ latency values in 0.5us units */
+ if (level > 0)
+ latency *= 5;
+
+ DRM_DEBUG_KMS("%s WM%d latency %u (%u.%u usec)\n",
+ name, level, wm[level],
+ latency / 10, latency % 10);
+ }
+}
+
static void intel_setup_wm_latency(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
@@ -2422,6 +2455,10 @@
intel_fixup_spr_wm_latency(dev, dev_priv->wm.spr_latency);
intel_fixup_cur_wm_latency(dev, dev_priv->wm.cur_latency);
+
+ intel_print_wm_latency(dev, "Primary", dev_priv->wm.pri_latency);
+ intel_print_wm_latency(dev, "Sprite", dev_priv->wm.spr_latency);
+ intel_print_wm_latency(dev, "Cursor", dev_priv->wm.cur_latency);
}
static void hsw_compute_wm_parameters(struct drm_device *dev,