crypto: ccp - Base AXI DMA cache settings on device tree

The default cache operations for ARM64 were changed during 3.15.
To use coherent operations a "dma-coherent" device tree property
is required.  If that property is not present in the device tree
node then the non-coherent operations are assigned for the device.

Add support to the ccp driver to assign the AXI DMA cache settings
based on whether the "dma-coherent" property is present in the device
node.  If present, use settings that work with the caches.  If not
present, use settings that do not look at the caches.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 3 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/crypto/amd-ccp.txt b/Documentation/devicetree/bindings/crypto/amd-ccp.txt
index 6e0b11aa8995..8c61183b41e0 100644
--- a/Documentation/devicetree/bindings/crypto/amd-ccp.txt
+++ b/Documentation/devicetree/bindings/crypto/amd-ccp.txt
@@ -7,6 +7,9 @@ Required properties:
   that services interrupts for this device
 - interrupts: Should contain the CCP interrupt
 
+Optional properties:
+- dma-coherent: Present if dma operations are coherent
+
 Example:
 	ccp@e0100000 {
 		compatible = "amd,ccp-seattle-v1a";