drm/i915: Work around DISPLAY_PHY_CONTROL register corruption on CHV
[firefly-linux-kernel-4.4.55.git] / drivers / gpu / drm / i915 / intel_runtime_pm.c
index ffbf9779c26d403e53adc85767bfd855643898d6..3d7352577bdce8fcd4b8e73ae1e630aa5e5dd2b6 100644 (file)
@@ -49,7 +49,8 @@
  * present for a given platform.
  */
 
-#define GEN9_ENABLE_DC5(dev) (IS_SKYLAKE(dev))
+#define GEN9_ENABLE_DC5(dev) 0
+#define SKL_ENABLE_DC6(dev) IS_SKYLAKE(dev)
 
 #define for_each_power_well(i, power_well, domain_mask, power_domains) \
        for (i = 0;                                                     \
@@ -64,6 +65,9 @@
             i--)                                                        \
                if ((power_well)->domains & (domain_mask))
 
+bool intel_display_power_well_is_enabled(struct drm_i915_private *dev_priv,
+                                   int power_well_id);
+
 /*
  * We should only use the power well if we explicitly asked the hardware to
  * enable it, so check if it's enabled and also check if we've requested it to
@@ -310,7 +314,9 @@ static void hsw_set_power_well(struct drm_i915_private *dev_priv,
        BIT(POWER_DOMAIN_PORT_DDI_D_4_LANES) |          \
        BIT(POWER_DOMAIN_INIT))
 #define SKL_DISPLAY_MISC_IO_POWER_DOMAINS (            \
-       SKL_DISPLAY_POWERWELL_1_POWER_DOMAINS)
+       SKL_DISPLAY_POWERWELL_1_POWER_DOMAINS |         \
+       BIT(POWER_DOMAIN_PLLS) |                        \
+       BIT(POWER_DOMAIN_INIT))
 #define SKL_DISPLAY_ALWAYS_ON_POWER_DOMAINS (          \
        (POWER_DOMAIN_MASK & ~(SKL_DISPLAY_POWERWELL_1_POWER_DOMAINS |  \
        SKL_DISPLAY_POWERWELL_2_POWER_DOMAINS |         \
@@ -419,14 +425,142 @@ void bxt_disable_dc9(struct drm_i915_private *dev_priv)
        POSTING_READ(DC_STATE_EN);
 }
 
+static void gen9_set_dc_state_debugmask_memory_up(
+                       struct drm_i915_private *dev_priv)
+{
+       uint32_t val;
+
+       /* The below bit doesn't need to be cleared ever afterwards */
+       val = I915_READ(DC_STATE_DEBUG);
+       if (!(val & DC_STATE_DEBUG_MASK_MEMORY_UP)) {
+               val |= DC_STATE_DEBUG_MASK_MEMORY_UP;
+               I915_WRITE(DC_STATE_DEBUG, val);
+               POSTING_READ(DC_STATE_DEBUG);
+       }
+}
+
+static void assert_can_enable_dc5(struct drm_i915_private *dev_priv)
+{
+       struct drm_device *dev = dev_priv->dev;
+       bool pg2_enabled = intel_display_power_well_is_enabled(dev_priv,
+                                       SKL_DISP_PW_2);
+
+       WARN(!IS_SKYLAKE(dev), "Platform doesn't support DC5.\n");
+       WARN(!HAS_RUNTIME_PM(dev), "Runtime PM not enabled.\n");
+       WARN(pg2_enabled, "PG2 not disabled to enable DC5.\n");
+
+       WARN((I915_READ(DC_STATE_EN) & DC_STATE_EN_UPTO_DC5),
+                               "DC5 already programmed to be enabled.\n");
+       WARN(dev_priv->pm.suspended,
+               "DC5 cannot be enabled, if platform is runtime-suspended.\n");
+
+       assert_csr_loaded(dev_priv);
+}
+
+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,
+               "Disabling of DC5 while platform is runtime-suspended should never happen.\n");
+}
+
 static void gen9_enable_dc5(struct drm_i915_private *dev_priv)
 {
-       /* TODO: Implementation to be done. */
+       uint32_t val;
+
+       assert_can_enable_dc5(dev_priv);
+
+       DRM_DEBUG_KMS("Enabling DC5\n");
+
+       gen9_set_dc_state_debugmask_memory_up(dev_priv);
+
+       val = I915_READ(DC_STATE_EN);
+       val &= ~DC_STATE_EN_UPTO_DC5_DC6_MASK;
+       val |= DC_STATE_EN_UPTO_DC5;
+       I915_WRITE(DC_STATE_EN, val);
+       POSTING_READ(DC_STATE_EN);
 }
 
 static void gen9_disable_dc5(struct drm_i915_private *dev_priv)
 {
-       /* TODO: Implementation to be done. */
+       uint32_t val;
+
+       assert_can_disable_dc5(dev_priv);
+
+       DRM_DEBUG_KMS("Disabling DC5\n");
+
+       val = I915_READ(DC_STATE_EN);
+       val &= ~DC_STATE_EN_UPTO_DC5;
+       I915_WRITE(DC_STATE_EN, val);
+       POSTING_READ(DC_STATE_EN);
+}
+
+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;
+
+       assert_can_enable_dc6(dev_priv);
+
+       DRM_DEBUG_KMS("Enabling DC6\n");
+
+       gen9_set_dc_state_debugmask_memory_up(dev_priv);
+
+       val = I915_READ(DC_STATE_EN);
+       val &= ~DC_STATE_EN_UPTO_DC5_DC6_MASK;
+       val |= DC_STATE_EN_UPTO_DC6;
+       I915_WRITE(DC_STATE_EN, val);
+       POSTING_READ(DC_STATE_EN);
+}
+
+static void skl_disable_dc6(struct drm_i915_private *dev_priv)
+{
+       uint32_t val;
+
+       assert_can_disable_dc6(dev_priv);
+
+       DRM_DEBUG_KMS("Disabling DC6\n");
+
+       val = I915_READ(DC_STATE_EN);
+       val &= ~DC_STATE_EN_UPTO_DC6;
+       I915_WRITE(DC_STATE_EN, val);
+       POSTING_READ(DC_STATE_EN);
 }
 
 static void skl_set_power_well(struct drm_i915_private *dev_priv,
@@ -476,9 +610,21 @@ static void skl_set_power_well(struct drm_i915_private *dev_priv,
                                !I915_READ(HSW_PWR_WELL_BIOS),
                                "Invalid for power well status to be enabled, unless done by the BIOS, \
                                when request is to disable!\n");
-                       if (GEN9_ENABLE_DC5(dev) &&
-                               power_well->data == SKL_DISP_PW_2)
-                               gen9_disable_dc5(dev_priv);
+                       if ((GEN9_ENABLE_DC5(dev) || SKL_ENABLE_DC6(dev)) &&
+                               power_well->data == SKL_DISP_PW_2) {
+                               if (SKL_ENABLE_DC6(dev)) {
+                                       skl_disable_dc6(dev_priv);
+                                       /*
+                                        * DDI buffer programming unnecessary during driver-load/resume
+                                        * as it's already done during modeset initialization then.
+                                        * It's also invalid here as encoder list is still uninitialized.
+                                        */
+                                       if (!dev_priv->power_domains.initializing)
+                                               intel_prepare_ddi(dev);
+                               } else {
+                                       gen9_disable_dc5(dev_priv);
+                               }
+                       }
                        I915_WRITE(HSW_PWR_WELL_DRIVER, tmp | req_mask);
                }
 
@@ -496,17 +642,23 @@ static void skl_set_power_well(struct drm_i915_private *dev_priv,
                        POSTING_READ(HSW_PWR_WELL_DRIVER);
                        DRM_DEBUG_KMS("Disabling %s\n", power_well->name);
 
-                       if (GEN9_ENABLE_DC5(dev) &&
+                       if ((GEN9_ENABLE_DC5(dev) || SKL_ENABLE_DC6(dev)) &&
                                power_well->data == SKL_DISP_PW_2) {
                                enum csr_state state;
-
+                               /* TODO: wait for a completion event or
+                                * similar here instead of busy
+                                * waiting using wait_for function.
+                                */
                                wait_for((state = intel_csr_load_status_get(dev_priv)) !=
                                                FW_UNINITIALIZED, 1000);
                                if (state != FW_LOADED)
                                        DRM_ERROR("CSR firmware not ready (%d)\n",
                                                        state);
                                else
-                                       gen9_enable_dc5(dev_priv);
+                                       if (SKL_ENABLE_DC6(dev))
+                                               skl_enable_dc6(dev_priv);
+                                       else
+                                               gen9_enable_dc5(dev_priv);
                        }
                }
        }
@@ -797,8 +949,8 @@ static void chv_dpio_cmn_power_well_enable(struct drm_i915_private *dev_priv,
        if (wait_for(I915_READ(DISPLAY_PHY_STATUS) & PHY_POWERGOOD(phy), 1))
                DRM_ERROR("Display PHY %d is not power up\n", phy);
 
-       I915_WRITE(DISPLAY_PHY_CONTROL, I915_READ(DISPLAY_PHY_CONTROL) |
-                  PHY_COM_LANE_RESET_DEASSERT(phy));
+       dev_priv->chv_phy_control |= PHY_COM_LANE_RESET_DEASSERT(phy);
+       I915_WRITE(DISPLAY_PHY_CONTROL, dev_priv->chv_phy_control);
 }
 
 static void chv_dpio_cmn_power_well_disable(struct drm_i915_private *dev_priv,
@@ -818,8 +970,8 @@ static void chv_dpio_cmn_power_well_disable(struct drm_i915_private *dev_priv,
                assert_pll_disabled(dev_priv, PIPE_C);
        }
 
-       I915_WRITE(DISPLAY_PHY_CONTROL, I915_READ(DISPLAY_PHY_CONTROL) &
-                  ~PHY_COM_LANE_RESET_DEASSERT(phy));
+       dev_priv->chv_phy_control &= ~PHY_COM_LANE_RESET_DEASSERT(phy);
+       I915_WRITE(DISPLAY_PHY_CONTROL, dev_priv->chv_phy_control);
 
        vlv_set_power_well(dev_priv, power_well, false);
 }
@@ -1379,7 +1531,7 @@ static struct i915_power_well chv_power_wells[] = {
 };
 
 static struct i915_power_well *lookup_power_well(struct drm_i915_private *dev_priv,
-                                                enum punit_power_well power_well_id)
+                                                int power_well_id)
 {
        struct i915_power_domains *power_domains = &dev_priv->power_domains;
        struct i915_power_well *power_well;
@@ -1393,6 +1545,18 @@ static struct i915_power_well *lookup_power_well(struct drm_i915_private *dev_pr
        return NULL;
 }
 
+bool intel_display_power_well_is_enabled(struct drm_i915_private *dev_priv,
+                                   int power_well_id)
+{
+       struct i915_power_well *power_well;
+       bool ret;
+
+       power_well = lookup_power_well(dev_priv, power_well_id);
+       ret = power_well->ops->is_enabled(dev_priv, power_well);
+
+       return ret;
+}
+
 static struct i915_power_well skl_power_wells[] = {
        {
                .name = "always-on",
@@ -1555,6 +1719,30 @@ static void intel_power_domains_resume(struct drm_i915_private *dev_priv)
        mutex_unlock(&power_domains->lock);
 }
 
+static void chv_phy_control_init(struct drm_i915_private *dev_priv)
+{
+       struct i915_power_well *cmn_bc =
+               lookup_power_well(dev_priv, PUNIT_POWER_WELL_DPIO_CMN_BC);
+       struct i915_power_well *cmn_d =
+               lookup_power_well(dev_priv, PUNIT_POWER_WELL_DPIO_CMN_D);
+
+       /*
+        * DISPLAY_PHY_CONTROL can get corrupted if read. As a
+        * workaround never ever read DISPLAY_PHY_CONTROL, and
+        * instead maintain a shadow copy ourselves. Use the actual
+        * power well state to reconstruct the expected initial
+        * value.
+        */
+       dev_priv->chv_phy_control =
+               PHY_CH_POWER_MODE(PHY_CH_SU_PSR, DPIO_PHY0, DPIO_CH0) |
+               PHY_CH_POWER_MODE(PHY_CH_SU_PSR, DPIO_PHY0, DPIO_CH1) |
+               PHY_CH_POWER_MODE(PHY_CH_SU_PSR, DPIO_PHY1, DPIO_CH0);
+       if (cmn_bc->ops->is_enabled(dev_priv, cmn_bc))
+               dev_priv->chv_phy_control |= PHY_COM_LANE_RESET_DEASSERT(DPIO_PHY0);
+       if (cmn_d->ops->is_enabled(dev_priv, cmn_d))
+               dev_priv->chv_phy_control |= PHY_COM_LANE_RESET_DEASSERT(DPIO_PHY1);
+}
+
 static void vlv_cmnlane_wa(struct drm_i915_private *dev_priv)
 {
        struct i915_power_well *cmn =
@@ -1597,7 +1785,9 @@ void intel_power_domains_init_hw(struct drm_i915_private *dev_priv)
 
        power_domains->initializing = true;
 
-       if (IS_VALLEYVIEW(dev) && !IS_CHERRYVIEW(dev)) {
+       if (IS_CHERRYVIEW(dev)) {
+               chv_phy_control_init(dev_priv);
+       } else if (IS_VALLEYVIEW(dev)) {
                mutex_lock(&power_domains->lock);
                vlv_cmnlane_wa(dev_priv);
                mutex_unlock(&power_domains->lock);