stmmac: extend mac addr reg and fix perfect filering

This patch is to extend the number of MAC address registers
for 16 to 32. In fact, other new 16 registers are available in new
chips and this can help on perfect filter mode for unicast.

This patch also fixes the perfect filtering mode by setting the
bit 31 in the MAC address registers.

v2: fixed Coding Style.

Signed-off-by: Gianni Antoniazzi <gianni.antoniazzi-ext@st.com>
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c b/drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c
index f20aa12..4e0e18a 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c
@@ -31,6 +31,8 @@
 #define DWMAC_LIB_DBG(fmt, args...)  do { } while (0)
 #endif
 
+#define GMAC_HI_REG_AE		0x80000000
+
 /* CSR1 enables the transmit DMA to check for new descriptor */
 void dwmac_enable_dma_transmission(void __iomem *ioaddr)
 {
@@ -233,7 +235,11 @@
 	unsigned long data;
 
 	data = (addr[5] << 8) | addr[4];
-	writel(data, ioaddr + high);
+	/* For MAC Addr registers se have to set the Address Enable (AE)
+	 * bit that has no effect on the High Reg 0 where the bit 31 (MO)
+	 * is RO.
+	 */
+	writel(data | GMAC_HI_REG_AE, ioaddr + high);
 	data = (addr[3] << 24) | (addr[2] << 16) | (addr[1] << 8) | addr[0];
 	writel(data, ioaddr + low);
 }