drm/i915: disable ppgtt on snb when dmar is enabled
Totally unexpected that this regressed. Luckily it sounds like we just
need to have dmar disable on the igfx, not the entire system. At least
that's what a few days of testing between Tony Vroon and me indicates.
Reported-by: Tony Vroon <tony@linx.net>
Cc: Tony Vroon <tony@linx.net>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43024
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 9341eb8..8a62285 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1183,6 +1183,21 @@
return can_switch;
}
+static bool
+intel_enable_ppgtt(struct drm_device *dev)
+{
+ if (i915_enable_ppgtt >= 0)
+ return i915_enable_ppgtt;
+
+#ifdef CONFIG_INTEL_IOMMU
+ /* Disable ppgtt on SNB if VT-d is on. */
+ if (INTEL_INFO(dev)->gen == 6 && intel_iommu_gfx_mapped)
+ return false;
+#endif
+
+ return true;
+}
+
static int i915_load_gem_init(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
@@ -1197,7 +1212,7 @@
drm_mm_init(&dev_priv->mm.stolen, 0, prealloc_size);
mutex_lock(&dev->struct_mutex);
- if (i915_enable_ppgtt && HAS_ALIASING_PPGTT(dev)) {
+ if (intel_enable_ppgtt(dev) && HAS_ALIASING_PPGTT(dev)) {
/* PPGTT pdes are stolen from global gtt ptes, so shrink the
* aperture accordingly when using aliasing ppgtt. */
gtt_size -= I915_PPGTT_PD_ENTRIES*PAGE_SIZE;
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 77afd31..19d55bc 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -107,8 +107,8 @@
"WARNING: Disabling this can cause system wide hangs. "
"(default: true)");
-bool i915_enable_ppgtt __read_mostly = 1;
-module_param_named(i915_enable_ppgtt, i915_enable_ppgtt, bool, 0600);
+int i915_enable_ppgtt __read_mostly = -1;
+module_param_named(i915_enable_ppgtt, i915_enable_ppgtt, int, 0600);
MODULE_PARM_DESC(i915_enable_ppgtt,
"Enable PPGTT (default: true)");
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 2c19227..5fabc6c 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1086,7 +1086,7 @@
extern int i915_enable_rc6 __read_mostly;
extern int i915_enable_fbc __read_mostly;
extern bool i915_enable_hangcheck __read_mostly;
-extern bool i915_enable_ppgtt __read_mostly;
+extern int i915_enable_ppgtt __read_mostly;
extern int i915_suspend(struct drm_device *dev, pm_message_t state);
extern int i915_resume(struct drm_device *dev);