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>

drivers/crypto/ccp/ccp-dev.h

@@ -30,6 +30,7 @@
 
 #define TRNG_RETRIES			10
 
+#define CACHE_NONE			0x00
 #define CACHE_WB_NO_ALLOC		0xb7
 
 
@@ -255,6 +256,9 @@ struct ccp_device {
 	/* Suspend support */
 	unsigned int suspending;
 	wait_queue_head_t suspend_queue;
+
+	/* DMA caching attribute support */
+	unsigned int axcache;
 };