amd-xgbe: Set DMA mask based on hardware register value

The hardware supplies a value that indicates the DMA range that it
is capable of using. Use this value rather than hard-coding it in
the driver.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
index 8635c94..ef4625e 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-drv.c
@@ -519,6 +519,7 @@
 						RXFIFOSIZE);
 	hw_feat->tx_fifo_size  = XGMAC_GET_BITS(mac_hfr1, MAC_HWF1R,
 						TXFIFOSIZE);
+	hw_feat->dma_width     = XGMAC_GET_BITS(mac_hfr1, MAC_HWF1R, ADDR64);
 	hw_feat->dcb           = XGMAC_GET_BITS(mac_hfr1, MAC_HWF1R, DCBEN);
 	hw_feat->sph           = XGMAC_GET_BITS(mac_hfr1, MAC_HWF1R, SPHEN);
 	hw_feat->tso           = XGMAC_GET_BITS(mac_hfr1, MAC_HWF1R, TSOEN);
@@ -553,6 +554,21 @@
 		break;
 	}
 
+	/* Translate the address width setting into actual number */
+	switch (hw_feat->dma_width) {
+	case 0:
+		hw_feat->dma_width = 32;
+		break;
+	case 1:
+		hw_feat->dma_width = 40;
+		break;
+	case 2:
+		hw_feat->dma_width = 48;
+		break;
+	default:
+		hw_feat->dma_width = 32;
+	}
+
 	/* The Queue, Channel and TC counts are zero based so increment them
 	 * to get the actual number
 	 */