[RFC 3/5] dt-bindings: arm-smmu: Add reserved-msi-region

Jitendra Bhivare jitendra.bhivare at broadcom.com
Mon Mar 5 20:59:26 PST 2018


iPROC SoC has a special device window to treat GICv3 ITS MSI.

Current code maps MSI to IOVA space. Add SMMU node property to use
direct mappings for MSI region.

This property is read and reserved when arm_smmu_get_resv_regions
gets called.

Signed-off-by: Jitendra Bhivare <jitendra.bhivare at broadcom.com>
---
 Documentation/devicetree/bindings/iommu/arm,smmu.txt | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
index 8a6ffce..13fa2b9 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
@@ -71,6 +71,15 @@ conditions.
                   or using stream matching with #iommu-cells = <2>, and
                   may be ignored if present in such cases.
 
+- reserved-msi-region: MSI region to be reserved with specific prot in IOVA
+		  space for direct mapping. The region is specified in tuple
+		  of (busno,prot,bus_addr,size).
+
+- #region-address-cells: specifies number of cells needed to encode bus_addr
+
+- #region-size-cells: specifies number of cells needed to encode size
+
+
 ** Deprecated properties:
 
 - mmu-masters (deprecated in favour of the generic "iommus" binding) :
@@ -95,6 +104,9 @@ conditions.
                              <0 36 4>,
                              <0 37 4>;
                 #iommu-cells = <1>;
+		#region-address-cells = <1>;
+		#region-size-cells = <1>;
+		reserved-msi-region = <0x0 0x1a 0x63c3000 0x8000>;
         };
 
         /* device with two stream IDs, 0 and 7 */
-- 
2.7.4




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