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authorGregory CLEMENT <gregory.clement@free-electrons.com>2012-10-12 19:20:36 +0200
committerGregory CLEMENT <gregory.clement@free-electrons.com>2012-11-21 17:07:49 +0100
commite60304f8cb7bb545e79fe62d9b9762460c254ec2 (patch)
tree9f28a557c71cf6128c7cf480b8a4a59f0c0bb6b8 /Documentation
parent722202e10b488c14e93c428743a0e476093949e3 (diff)
downloadop-kernel-dev-e60304f8cb7bb545e79fe62d9b9762460c254ec2.zip
op-kernel-dev-e60304f8cb7bb545e79fe62d9b9762460c254ec2.tar.gz
arm: mvebu: Add hardware I/O Coherency support
Armada 370 and XP come with an unit called coherency fabric. This unit allows to use the Armada 370/XP as a nearly coherent architecture. The coherency mechanism uses snoop filters to ensure the coherency between caches, DRAM and devices. This mechanism needs a synchronization barrier which guarantees that all the memory writes initiated by the devices have reached their target and do not reside in intermediate write buffers. That's why the architecture is not totally coherent and we need to provide our own functions for some DMA operations. Beside the use of the coherency fabric, the device units will have to set the attribute flag of the decoding address window to select the accurate coherency process for the memory transaction. This is done each device driver programs the DRAM address windows. The value of the attribute set by the driver is retrieved through the orion_addr_map_cfg struct filled during the early initialization of the platform. Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Reviewed-by: Yehuda Yitschak <yehuday@marvell.com> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/arm/coherency-fabric.txt9
1 files changed, 7 insertions, 2 deletions
diff --git a/Documentation/devicetree/bindings/arm/coherency-fabric.txt b/Documentation/devicetree/bindings/arm/coherency-fabric.txt
index 2bfbf67..17d8cd1 100644
--- a/Documentation/devicetree/bindings/arm/coherency-fabric.txt
+++ b/Documentation/devicetree/bindings/arm/coherency-fabric.txt
@@ -5,12 +5,17 @@ Available on Marvell SOCs: Armada 370 and Armada XP
Required properties:
- compatible: "marvell,coherency-fabric"
-- reg: Should contain,coherency fabric registers location and length.
+
+- reg: Should contain coherency fabric registers location and
+ length. First pair for the coherency fabric registers, second pair
+ for the per-CPU fabric registers registers.
Example:
coherency-fabric@d0020200 {
compatible = "marvell,coherency-fabric";
- reg = <0xd0020200 0xb0>;
+ reg = <0xd0020200 0xb0>,
+ <0xd0021810 0x1c>;
+
};
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