net: sh_eth: Fix RX packets errors on R8A7740

This patch will fix RX packets errors when receiving big size
of data by set bit RNC = 1.

RNC - Receive Enable Control

0: Upon completion of reception of one frame, the E-DMAC writes
the receive status to the descriptor and clears the RR bit in
EDRRR to 0.

1: Upon completion of reception of one frame, the E-DMAC writes
(writes back) the receive status to the descriptor. In addition,
the E-DMAC reads the next descriptor and prepares for reception
of the next frame.

In addition, for get more stable when receiving packets, I set
maximum size for the transmit/receive FIFO and inserts padding
in receive data.
Signed-off-by: Nguyen Hong Ky <nh-ky@jinso.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/renesas/sh_eth.c

@@ -620,12 +620,16 @@ static struct sh_eth_cpu_data sh7734_data = {
 	.eesr_err_check	= EESR_TWB1 | EESR_TWB | EESR_TABT | EESR_RABT |
 			  EESR_RFE | EESR_RDE | EESR_RFRMER | EESR_TFE |
 			  EESR_TDE | EESR_ECI,
+	.fdr_value	= 0x0000070f,
+	.rmcr_value	= 0x00000001,
 
 	.apr		= 1,
 	.mpr		= 1,
 	.tpauser	= 1,
 	.bculr		= 1,
 	.hw_swap	= 1,
+	.rpadir		= 1,
+	.rpadir_value   = 2 << 16,
 	.no_trimd	= 1,
 	.no_ade		= 1,
 	.tsu		= 1,