gianfar: Make MAC addr setup endian safe, cleanup

Fix the 32-bit memory access that is not endian safe,
i.e. not giving the desired byte layout for a LE CPU:
tempval = *((u32 *) (tmpbuf + 4)), where 'char tmpbuf[]'.

Get rid of rendundant local vars (tmpbuf[] and idx) and
forced casts.  Cleanup comments.

Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 8 deletions

diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c
index 37e060478630..961198a2bfa8 100644
--- a/drivers/net/ethernet/freescale/gianfar.c
+++ b/drivers/net/ethernet/freescale/gianfar.c
@@ -3248,22 +3248,21 @@ static void gfar_set_mac_for_addr(struct net_device *dev, int num,
 {
         struct gfar_private *priv = netdev_priv(dev);
         struct gfar __iomem *regs = priv->gfargrp[0].regs;
-        int idx;
-        char tmpbuf[ETH_ALEN];
         u32 tempval;
         u32 __iomem *macptr = &regs->macstnaddr1;
 
         macptr += num*2;
 
-        /* Now copy it into the mac registers backwards, cuz
-         * little endian is silly
+        /* For a station address of 0x12345678ABCD in transmission
+         * order (BE), MACnADDR1 is set to 0xCDAB7856 and
+         * MACnADDR2 is set to 0x34120000.
          */
-        for (idx = 0; idx < ETH_ALEN; idx++)
-                tmpbuf[ETH_ALEN - 1 - idx] = addr[idx];
+        tempval = (addr[5] << 24) | (addr[4] << 16) |
+                  (addr[3] << 8)  |  addr[2];
 
-        gfar_write(macptr, *((u32 *) (tmpbuf)));
+        gfar_write(macptr, tempval);
 
-        tempval = *((u32 *) (tmpbuf + 4));
+        tempval = (addr[1] << 24) | (addr[0] << 16);
 
         gfar_write(macptr+1, tempval);
 }