drm/i915: Polish some dbuf debugs

Polish some of the dbuf code to give more meaningful debug
messages and whatnot. Also we can switch over to the per-device
debugs/warns at the same time.

Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200225171125.28885-7-ville.syrjala@linux.intel.com
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>

diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
index 4999890..f473471 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -4491,10 +4491,12 @@ static void intel_power_domains_sync_hw(struct drm_i915_private *dev_priv)
        mutex_unlock(&power_domains->lock);
 }
 
-static bool intel_dbuf_slice_set(struct drm_i915_private *dev_priv,
-                                i915_reg_t reg, bool enable)
+static void intel_dbuf_slice_set(struct drm_i915_private *dev_priv,
+                                enum dbuf_slice slice, bool enable)
 {
-       u32 val, status;
+       i915_reg_t reg = DBUF_CTL_S(slice);
+       bool state;
+       u32 val;
 
        val = intel_de_read(dev_priv, reg);
        val = enable ? (val | DBUF_POWER_REQUEST) : (val & ~DBUF_POWER_REQUEST);
@@ -4502,13 +4504,10 @@ static bool intel_dbuf_slice_set(struct drm_i915_private *dev_priv,
        intel_de_posting_read(dev_priv, reg);
        udelay(10);
 
-       status = intel_de_read(dev_priv, reg) & DBUF_POWER_STATE;
-       if ((enable && !status) || (!enable && status)) {
-               drm_err(&dev_priv->drm, "DBus power %s timeout!\n",
-                       enable ? "enable" : "disable");
-               return false;
-       }
-       return true;
+       state = intel_de_read(dev_priv, reg) & DBUF_POWER_STATE;
+       drm_WARN(&dev_priv->drm, enable != state,
+                "DBuf slice %d power %s timeout!\n",
+                slice, enable ? "enable" : "disable");
 }
 
 static void gen9_dbuf_enable(struct drm_i915_private *dev_priv)
@@ -4524,12 +4523,13 @@ static void gen9_dbuf_disable(struct drm_i915_private *dev_priv)
 void icl_dbuf_slices_update(struct drm_i915_private *dev_priv,
                            u8 req_slices)
 {
-       int i;
-       int max_slices = INTEL_INFO(dev_priv)->num_supported_dbuf_slices;
+       int num_slices = INTEL_INFO(dev_priv)->num_supported_dbuf_slices;
        struct i915_power_domains *power_domains = &dev_priv->power_domains;
+       enum dbuf_slice slice;
 
-       drm_WARN(&dev_priv->drm, hweight8(req_slices) > max_slices,
-                "Invalid number of dbuf slices requested\n");
+       drm_WARN(&dev_priv->drm, req_slices & ~(BIT(num_slices) - 1),
+                "Invalid set of dbuf slices (0x%x) requested (num dbuf slices %d)\n",
+                req_slices, num_slices);
 
        drm_dbg_kms(&dev_priv->drm, "Updating dbuf slices to 0x%x\n",
                    req_slices);
@@ -4543,11 +4543,9 @@ void icl_dbuf_slices_update(struct drm_i915_private *dev_priv,
         */
        mutex_lock(&power_domains->lock);
 
-       for (i = 0; i < max_slices; i++) {
-               intel_dbuf_slice_set(dev_priv,
-                                    DBUF_CTL_S(i),
-                                    (req_slices & BIT(i)) != 0);
-       }
+       for (slice = DBUF_S1; slice < num_slices; slice++)
+               intel_dbuf_slice_set(dev_priv, slice,
+                                    req_slices & BIT(slice));
 
        dev_priv->enabled_dbuf_slices_mask = req_slices;