iommu: Export intel_iommu_enabled to signal when iommu is in use
In i915 driver, we do not enable either rc6 or semaphores on SNB when dmar
is enabled. The new 'intel_iommu_enabled' variable signals when the
iommu code is in operation.
Cc: Ted Phelps <phelps@gnusto.com>
Cc: Peter <pab1612@gmail.com>
Cc: Lukas Hejtmanek <xhejtman@fi.muni.cz>
Cc: Andrew Lutomirski <luto@mit.edu>
CC: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index c0c7820..8dc19b8 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -405,6 +405,9 @@
int dmar_disabled = 1;
#endif /*CONFIG_INTEL_IOMMU_DEFAULT_ON*/
+int intel_iommu_enabled = 0;
+EXPORT_SYMBOL_GPL(intel_iommu_enabled);
+
static int dmar_map_gfx = 1;
static int dmar_forcedac;
static int intel_iommu_strict;
@@ -3647,6 +3650,8 @@
bus_register_notifier(&pci_bus_type, &device_nb);
+ intel_iommu_enabled = 1;
+
return 0;
}
diff --git a/include/linux/dma_remapping.h b/include/linux/dma_remapping.h
index ef90cbd..57c9a8a 100644
--- a/include/linux/dma_remapping.h
+++ b/include/linux/dma_remapping.h
@@ -31,6 +31,7 @@
extern int iommu_calculate_agaw(struct intel_iommu *iommu);
extern int iommu_calculate_max_sagaw(struct intel_iommu *iommu);
extern int dmar_disabled;
+extern int intel_iommu_enabled;
#else
static inline int iommu_calculate_agaw(struct intel_iommu *iommu)
{
@@ -44,6 +45,7 @@
{
}
#define dmar_disabled (1)
+#define intel_iommu_enabled (0)
#endif