net/ibm/emac: add 8192 rx/tx fifo size

emac4syn chips has availability to use 8192 rx/tx fifo buffer sizes,
in current state if we set it up in dts 8192 as example, we will get
only 2048 which may impact on network speed.
Signed-off-by: NIvan Mikhaylov <ivan@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/ibm/emac/core.c

@@ -494,6 +494,9 @@ static u32 __emac_calc_base_mr1(struct emac_instance *dev, int tx_size, int rx_s
 	case 16384:
 		ret |= EMAC_MR1_RFS_16K;
 		break;
+	case 8192:
+		ret |= EMAC4_MR1_RFS_8K;
+		break;
 	case 4096:
 		ret |= EMAC_MR1_RFS_4K;
 		break;
@@ -516,6 +519,9 @@ static u32 __emac4_calc_base_mr1(struct emac_instance *dev, int tx_size, int rx_
 	case 16384:
 		ret |= EMAC4_MR1_TFS_16K;
 		break;
+	case 8192:
+		ret |= EMAC4_MR1_TFS_8K;
+		break;
 	case 4096:
 		ret |= EMAC4_MR1_TFS_4K;
 		break;

drivers/net/ethernet/ibm/emac/emac.h

@@ -151,9 +151,11 @@ struct emac_regs {
 
 #define EMAC4_MR1_RFS_2K		0x00100000
 #define EMAC4_MR1_RFS_4K		0x00180000
+#define EMAC4_MR1_RFS_8K		0x00200000
 #define EMAC4_MR1_RFS_16K		0x00280000
 #define EMAC4_MR1_TFS_2K       		0x00020000
 #define EMAC4_MR1_TFS_4K		0x00030000
+#define EMAC4_MR1_TFS_8K		0x00040000
 #define EMAC4_MR1_TFS_16K		0x00050000
 #define EMAC4_MR1_TR			0x00008000
 #define EMAC4_MR1_MWSW_001		0x00001000