drm/i915/skl: Assert the requirements to enter or exit DC6.
authorSuketu Shah <suketu.j.shah@intel.com>
Thu, 16 Apr 2015 08:52:13 +0000 (14:22 +0530)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Fri, 8 May 2015 11:03:16 +0000 (13:03 +0200)
Warn if the conditions to enter or exit DC6 are not satisfied such
as support for runtime PM, state of power well, CSR loading etc.

v2: Removed camelcase in functions and variables.

v3: Do some minimal check to assert if CSR program is not loaded.

v4:
1] Correct the check for backlight-disabling in assert_can_enable_dc6().
2] Check csr.loaded = false before disabling DC6 and simplify other checks.

v5:
1] Remove checks for DC5 state from assert_can_enable_dc6 function as DC5 is no
   longer enabled before enabling DC6.
2] Correct the check for CSR-loading in assert_can_disable_dc6 function as CSR must
   be loaded for context restore to happen on DC6 disabling.

v6:
1] It's okay to explicitly disable DC6 during driver-load/resume even though it might
   already be disabled and so don't warn about it.

v7: Rebase to latest.

v8: Sqashed the patch from Imre -
[PATCH] drm/i915/skl: avoid false CSR fw not loaded WARN during driver load/resume

v9: After adding dmc ver 1.0 support rebased on top of nightly. (Animesh)

v10: During initialization added a early return before disabling DC5. (Animesh)

Issue: VIZ-2819
Signed-off-by: A.Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Suketu Shah <suketu.j.shah@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drivers/gpu/drm/i915/intel_runtime_pm.c

index 39810844a9c9ae4c9f37b21176d4ea98d977dbf2..b393db78e5cb2ba9c1596c722c523a64d5be9570 100644 (file)
@@ -459,6 +459,12 @@ static void assert_can_disable_dc5(struct drm_i915_private *dev_priv)
 {
        bool pg2_enabled = intel_display_power_well_is_enabled(dev_priv,
                                        SKL_DISP_PW_2);
+       /*
+        * During initialization, the firmware may not be loaded yet.
+        * We still want to make sure that the DC enabling flag is cleared.
+        */
+       if (dev_priv->power_domains.initializing)
+               return;
 
        WARN(!pg2_enabled, "PG2 not enabled to disable DC5.\n");
        WARN(dev_priv->pm.suspended,
@@ -496,12 +502,39 @@ static void gen9_disable_dc5(struct drm_i915_private *dev_priv)
        POSTING_READ(DC_STATE_EN);
 }
 
-static void skl_enable_dc6(struct drm_i915_private *dev_priv)
+static void assert_can_enable_dc6(struct drm_i915_private *dev_priv)
 {
        struct drm_device *dev = dev_priv->dev;
+
+       WARN(!IS_SKYLAKE(dev), "Platform doesn't support DC6.\n");
+       WARN(!HAS_RUNTIME_PM(dev), "Runtime PM not enabled.\n");
+       WARN(I915_READ(UTIL_PIN_CTL) & UTIL_PIN_ENABLE,
+               "Backlight is not disabled.\n");
+       WARN((I915_READ(DC_STATE_EN) & DC_STATE_EN_UPTO_DC6),
+               "DC6 already programmed to be enabled.\n");
+
+       assert_csr_loaded(dev_priv);
+}
+
+static void assert_can_disable_dc6(struct drm_i915_private *dev_priv)
+{
+       /*
+        * During initialization, the firmware may not be loaded yet.
+        * We still want to make sure that the DC enabling flag is cleared.
+        */
+       if (dev_priv->power_domains.initializing)
+               return;
+
+       assert_csr_loaded(dev_priv);
+       WARN(!(I915_READ(DC_STATE_EN) & DC_STATE_EN_UPTO_DC6),
+               "DC6 already programmed to be disabled.\n");
+}
+
+static void skl_enable_dc6(struct drm_i915_private *dev_priv)
+{
        uint32_t val;
 
-       WARN_ON(!IS_SKYLAKE(dev));
+       assert_can_enable_dc6(dev_priv);
 
        DRM_DEBUG_KMS("Enabling DC6\n");
 
@@ -516,10 +549,9 @@ static void skl_enable_dc6(struct drm_i915_private *dev_priv)
 
 static void skl_disable_dc6(struct drm_i915_private *dev_priv)
 {
-       struct drm_device *dev = dev_priv->dev;
        uint32_t val;
 
-       WARN_ON(!IS_SKYLAKE(dev));
+       assert_can_disable_dc6(dev_priv);
 
        DRM_DEBUG_KMS("Disabling DC6\n");