drm/i915: Assert that VED and ISP are power gated

As there are no upstream drivers for VED or ISP let's just
assert that they are power gated. Otherwise they would
prevent s0ix entry.

For ISP this is only relevant when it is not exposed as a
PCI device and instead is a subordinate of the gunit. When
exposed as a PCI device it will be handled by the
atomisp2_pm driver.

On my VLV FFRD8 board the firmware power gates both of these
by default. Let's assume that is always the case and just
WARN if we ever encounter something different.

Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181129175504.3630-2-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 2d8673150c44..aa974b11928a 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -3993,6 +3993,36 @@ static void vlv_cmnlane_wa(struct drm_i915_private *dev_priv)
 	cmn->desc->ops->disable(dev_priv, cmn);
 }
 
+static bool vlv_punit_is_power_gated(struct drm_i915_private *dev_priv, u32 reg0)
+{
+	bool ret;
+
+	mutex_lock(&dev_priv->pcu_lock);
+	ret = (vlv_punit_read(dev_priv, reg0) & SSPM0_SSC_MASK) == SSPM0_SSC_PWR_GATE;
+	mutex_unlock(&dev_priv->pcu_lock);
+
+	return ret;
+}
+
+static void assert_ved_power_gated(struct drm_i915_private *dev_priv)
+{
+	WARN(!vlv_punit_is_power_gated(dev_priv, PUNIT_REG_VEDSSPM0),
+	     "VED not power gated\n");
+}
+
+static void assert_isp_power_gated(struct drm_i915_private *dev_priv)
+{
+	static const struct pci_device_id isp_ids[] = {
+		{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f38)},
+		{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x22b8)},
+		{}
+	};
+
+	WARN(!pci_dev_present(isp_ids) &&
+	     !vlv_punit_is_power_gated(dev_priv, PUNIT_REG_ISPSSPM0),
+	     "ISP not power gated\n");
+}
+
 static void intel_power_domains_verify_state(struct drm_i915_private *dev_priv);
 
 /**
@@ -4029,10 +4059,13 @@ void intel_power_domains_init_hw(struct drm_i915_private *i915, bool resume)
 		mutex_lock(&power_domains->lock);
 		chv_phy_control_init(i915);
 		mutex_unlock(&power_domains->lock);
+		assert_isp_power_gated(i915);
 	} else if (IS_VALLEYVIEW(i915)) {
 		mutex_lock(&power_domains->lock);
 		vlv_cmnlane_wa(i915);
 		mutex_unlock(&power_domains->lock);
+		assert_ved_power_gated(i915);
+		assert_isp_power_gated(i915);
 	} else if (IS_IVYBRIDGE(i915) || INTEL_GEN(i915) >= 7) {
 		intel_pch_reset_handshake(i915, !HAS_PCH_NOP(i915));
 	}