net: davinci_emac: Remove useless dcache ops on descriptors

ATM the rx and tx descriptors are handled as cached memory while they
lie in a dedicated RAM of the SoCs, which is an uncached area.
Removing the said dcache ops, while optimizing the logic and clarifying
the code, also gets rid of most of the check_cache_range() incurred
warnings:
CACHE: Misaligned operation at range

Signed-off-by: Karl Beldan <karl.beldan+oss@gmail.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/davinci_emac.c b/drivers/net/davinci_emac.c
index ca457b8..c591773 100644
--- a/drivers/net/davinci_emac.c
+++ b/drivers/net/davinci_emac.c
@@ -108,26 +108,6 @@
 
 phy_t				phy[CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT];
 
-static inline void davinci_flush_rx_descs(void)
-{
-	/* flush the whole RX descs area */
-	flush_dcache_range(EMAC_WRAPPER_RAM_ADDR + EMAC_RX_DESC_BASE,
-			EMAC_WRAPPER_RAM_ADDR + EMAC_TX_DESC_BASE);
-}
-
-static inline void davinci_invalidate_rx_descs(void)
-{
-	/* invalidate the whole RX descs area */
-	invalidate_dcache_range(EMAC_WRAPPER_RAM_ADDR + EMAC_RX_DESC_BASE,
-			EMAC_WRAPPER_RAM_ADDR + EMAC_TX_DESC_BASE);
-}
-
-static inline void davinci_flush_desc(emac_desc *desc)
-{
-	flush_dcache_range((unsigned long)desc,
-			(unsigned long)desc + sizeof(*desc));
-}
-
 static int davinci_eth_set_mac_addr(struct eth_device *dev)
 {
 	unsigned long		mac_hi;
@@ -496,8 +476,6 @@
 	emac_rx_active_tail = rx_desc;
 	emac_rx_queue_active = 1;
 
-	davinci_flush_rx_descs();
-
 	/* Enable TX/RX */
 	writel(EMAC_MAX_ETHERNET_PKT_SIZE, &adap_emac->RXMAXLEN);
 	writel(0, &adap_emac->RXBUFFEROFFSET);
@@ -660,7 +638,6 @@
 
 	flush_dcache_range((unsigned long)packet,
 			(unsigned long)packet + length);
-	davinci_flush_desc(emac_tx_desc);
 
 	/* Send the packet */
 	writel(BD_TO_HW((unsigned long)emac_tx_desc), &adap_emac->TX0HDP);
@@ -694,8 +671,6 @@
 	volatile emac_desc *tail_desc;
 	int status, ret = -1;
 
-	davinci_invalidate_rx_descs();
-
 	rx_curr_desc = emac_rx_active_head;
 	if (!rx_curr_desc)
 		return 0;
@@ -734,7 +709,6 @@
 		rx_curr_desc->buff_off_len = EMAC_MAX_ETHERNET_PKT_SIZE;
 		rx_curr_desc->pkt_flag_len = EMAC_CPPI_OWNERSHIP_BIT;
 		rx_curr_desc->next = 0;
-		davinci_flush_desc(rx_curr_desc);
 
 		if (emac_rx_active_head == 0) {
 			printf ("INFO: emac_rcv_pkt: active queue head = 0\n");
@@ -752,13 +726,11 @@
 			tail_desc->next = BD_TO_HW((ulong) curr_desc);
 			status = tail_desc->pkt_flag_len;
 			if (status & EMAC_CPPI_EOQ_BIT) {
-				davinci_flush_desc(tail_desc);
 				writel(BD_TO_HW((ulong)curr_desc),
 				       &adap_emac->RX0HDP);
 				status &= ~EMAC_CPPI_EOQ_BIT;
 				tail_desc->pkt_flag_len = status;
 			}
-			davinci_flush_desc(tail_desc);
 		}
 		return (ret);
 	}