drm/i915: Consolidate #ifdef CONFIG_INTEL_IOMMU

We depend on intel_iommu_gfx_mapped for various workarounds, but that is
only available under an #ifdef CONFIG_INTEL_IOMMU. Refactor all the
cut-and-paste ifdefs to a common routine.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170525121612.2190-1-chris@chris-wilson.co.ukReviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

drivers/gpu/drm/i915/i915_drv.h

@@ -2997,23 +2997,24 @@ intel_info(const struct drm_i915_private *dev_priv)
 
 #include "i915_trace.h"
 
-static inline bool intel_scanout_needs_vtd_wa(struct drm_i915_private *dev_priv)
+static inline bool intel_vtd_active(void)
 {
 #ifdef CONFIG_INTEL_IOMMU
-	if (INTEL_GEN(dev_priv) >= 6 && intel_iommu_gfx_mapped)
+	if (intel_iommu_gfx_mapped)
 		return true;
 #endif
 	return false;
 }
 
+static inline bool intel_scanout_needs_vtd_wa(struct drm_i915_private *dev_priv)
+{
+	return INTEL_GEN(dev_priv) >= 6 && intel_vtd_active();
+}
+
 static inline bool
 intel_ggtt_update_needs_vtd_wa(struct drm_i915_private *dev_priv)
 {
-#ifdef CONFIG_INTEL_IOMMU
-	if (IS_BROXTON(dev_priv) && intel_iommu_gfx_mapped)
-		return true;
-#endif
-	return false;
+	return IS_BROXTON(dev_priv) && intel_vtd_active();
 }
 
 int intel_sanitize_enable_ppgtt(struct drm_i915_private *dev_priv,

drivers/gpu/drm/i915/i915_gem.c

@@ -4728,11 +4728,9 @@ bool intel_sanitize_semaphores(struct drm_i915_private *dev_priv, int value)
 	if (value >= 0)
 		return value;
 
-#ifdef CONFIG_INTEL_IOMMU
 	/* Enable semaphores on SNB when IO remapping is off */
-	if (INTEL_INFO(dev_priv)->gen == 6 && intel_iommu_gfx_mapped)
+	if (IS_GEN6(dev_priv) && intel_vtd_active())
 		return false;
-#endif
 
 	return true;
 }

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -166,13 +166,11 @@ int intel_sanitize_enable_ppgtt(struct drm_i915_private *dev_priv,
 	if (enable_ppgtt == 3 && has_full_48bit_ppgtt)
 		return 3;
 
-#ifdef CONFIG_INTEL_IOMMU
 	/* Disable ppgtt on SNB if VT-d is on. */
-	if (IS_GEN6(dev_priv) && intel_iommu_gfx_mapped) {
+	if (IS_GEN6(dev_priv) && intel_vtd_active()) {
 		DRM_INFO("Disabling PPGTT because VT-d is on\n");
 		return 0;
 	}
-#endif
 
 	/* Early VLV doesn't have this */
 	if (IS_VALLEYVIEW(dev_priv) && dev_priv->drm.pdev->revision < 0xb) {
@@ -1990,14 +1988,10 @@ void i915_ppgtt_release(struct kref *kref)
  */
 static bool needs_idle_maps(struct drm_i915_private *dev_priv)
 {
-#ifdef CONFIG_INTEL_IOMMU
 	/* Query intel_iommu to see if we need the workaround. Presumably that
 	 * was loaded first.
 	 */
-	if (IS_GEN5(dev_priv) && IS_MOBILE(dev_priv) && intel_iommu_gfx_mapped)
-		return true;
-#endif
-	return false;
+	return IS_GEN5(dev_priv) && IS_MOBILE(dev_priv) && intel_vtd_active();
 }
 
 void i915_check_and_clear_faults(struct drm_i915_private *dev_priv)
@@ -3037,10 +3031,8 @@ int i915_ggtt_probe_hw(struct drm_i915_private *dev_priv)
 		 ggtt->base.total >> 20);
 	DRM_DEBUG_DRIVER("GMADR size = %lldM\n", ggtt->mappable_end >> 20);
 	DRM_DEBUG_DRIVER("GTT stolen size = %uM\n", ggtt->stolen_size >> 20);
-#ifdef CONFIG_INTEL_IOMMU
-	if (intel_iommu_gfx_mapped)
+	if (intel_vtd_active())
 		DRM_INFO("VT-d active for gfx access\n");
-#endif
 
 	return 0;
 }

drivers/gpu/drm/i915/i915_gem_stolen.c

@@ -414,12 +414,10 @@ int i915_gem_init_stolen(struct drm_i915_private *dev_priv)
 		return 0;
 	}
 
-#ifdef CONFIG_INTEL_IOMMU
-	if (intel_iommu_gfx_mapped && INTEL_GEN(dev_priv) < 8) {
+	if (intel_vtd_active() && INTEL_GEN(dev_priv) < 8) {
 		DRM_INFO("DMAR active, disabling use of stolen memory\n");
 		return 0;
 	}
-#endif
 
 	if (ggtt->stolen_size == 0)
 		return 0;

drivers/gpu/drm/i915/intel_fbc.c

@@ -1312,14 +1312,12 @@ static int intel_sanitize_fbc_option(struct drm_i915_private *dev_priv)
 
 static bool need_fbc_vtd_wa(struct drm_i915_private *dev_priv)
 {
-#ifdef CONFIG_INTEL_IOMMU
 	/* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl,bxt */
-	if (intel_iommu_gfx_mapped &&
+	if (intel_vtd_active() &&
 	    (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))) {
 		DRM_INFO("Disabling framebuffer compression (FBC) to prevent screen flicker with VT-d enabled\n");
 		return true;
 	}
-#endif
 
 	return false;
 }