amd-xgbe: 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 amd-xgbe 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: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 4 deletions

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe.h b/drivers/net/ethernet/amd/xgbe/xgbe.h
index eef8ea1dee47..9e24b296e272 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe.h
@@ -143,10 +143,14 @@
 #define XGBE_MAX_DMA_CHANNELS	16
 
 /* DMA cache settings - Outer sharable, write-back, write-allocate */
-#define XGBE_DMA_ARDOMAIN	0x2
-#define XGBE_DMA_ARCACHE	0xb
-#define XGBE_DMA_AWDOMAIN	0x2
-#define XGBE_DMA_AWCACHE	0xf
+#define XGBE_DMA_OS_AXDOMAIN	0x2
+#define XGBE_DMA_OS_ARCACHE	0xb
+#define XGBE_DMA_OS_AWCACHE	0xf
+
+/* DMA cache settings - System, no caches used */
+#define XGBE_DMA_SYS_AXDOMAIN	0x3
+#define XGBE_DMA_SYS_ARCACHE	0x0
+#define XGBE_DMA_SYS_AWCACHE	0x0
 
 #define XGBE_DMA_INTERRUPT_MASK	0x31c7
 
@@ -536,6 +540,11 @@ struct xgbe_prv_data {
 	struct xgbe_hw_if hw_if;
 	struct xgbe_desc_if desc_if;
 
+	/* AXI DMA settings */
+	unsigned int axdomain;
+	unsigned int arcache;
+	unsigned int awcache;
+
 	/* Rings for Tx/Rx on a DMA channel */
 	struct xgbe_channel *channel;
 	unsigned int channel_count;