net: ezchip: fix address space confusion in nps_enet.c

The nps_enet driver happily mixes virtual, physical and __iomem
addresses, which are all different depending on the architecture
and configuration.  That causes a warning when building the code
on ARM with LPAE mode enabled:

drivers/net/ethernet/ezchip/nps_enet.c: In function 'nps_enet_send_frame':
drivers/net/ethernet/ezchip/nps_enet.c:370:13: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]

but will also fail to work for other reasons.

In this patch, I'm trying to change the code to use only normal
kernel pointers, which I assume is what the author actually meant:

* For reading or writing a 32-bit word that may be unaligned when
  an SKB contains unaligned data, I'm using get_unaligned/put_unaligned()
  rather than memcpy_fromio/toio.

* For converting a u8 pointer to a u32 pointer, I use a cast rather
  than the incorrect virt_to_phys.

* For copying a couple of bytes from one place to another while respecting
  alignment, I use memcpy instead of memcpy_toio.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/ezchip/nps_enet.c b/drivers/net/ethernet/ezchip/nps_enet.c
index 63c2bcf8031a8a8cc39c714bb1510e3f3ae03793..b1026689b78f4075d30b240b4f8dc625d3b9299a 100644 (file)
--- a/drivers/net/ethernet/ezchip/nps_enet.c
+++ b/drivers/net/ethernet/ezchip/nps_enet.c
@@ -48,21 +48,15 @@ static void nps_enet_read_rx_fifo(struct net_device *ndev,
                        *reg = nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
        else { /* !dst_is_aligned */
                for (i = 0; i < len; i++, reg++) {
-                       u32 buf =
-                               nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
-
-                       /* to accommodate word-unaligned address of "reg"
-                        * we have to do memcpy_toio() instead of simple "=".
-                        */
-                       memcpy_toio((void __iomem *)reg, &buf, sizeof(buf));
+                       u32 buf = nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
+                       put_unaligned(buf, reg);
                }
        }
 
        /* copy last bytes (if any) */
        if (last) {
                u32 buf = nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF);
-
-               memcpy_toio((void __iomem *)reg, &buf, last);
+               memcpy((u8*)reg, &buf, last);
        }
 }
 
@@ -367,7 +361,7 @@ static void nps_enet_send_frame(struct net_device *ndev,
        struct nps_enet_tx_ctl tx_ctrl;
        short length = skb->len;
        u32 i, len = DIV_ROUND_UP(length, sizeof(u32));
-       u32 *src = (u32 *)virt_to_phys(skb->data);
+       u32 *src = (void *)skb->data;
        bool src_is_aligned = IS_ALIGNED((unsigned long)src, sizeof(u32));
 
        tx_ctrl.value = 0;
@@ -375,17 +369,11 @@ static void nps_enet_send_frame(struct net_device *ndev,
        if (src_is_aligned)
                for (i = 0; i < len; i++, src++)
                        nps_enet_reg_set(priv, NPS_ENET_REG_TX_BUF, *src);
-       else { /* !src_is_aligned */
-               for (i = 0; i < len; i++, src++) {
-                       u32 buf;
-
-                       /* to accommodate word-unaligned address of "src"
-                        * we have to do memcpy_fromio() instead of simple "="
-                        */
-                       memcpy_fromio(&buf, (void __iomem *)src, sizeof(buf));
-                       nps_enet_reg_set(priv, NPS_ENET_REG_TX_BUF, buf);
-               }
-       }
+       else /* !src_is_aligned */
+               for (i = 0; i < len; i++, src++)
+                       nps_enet_reg_set(priv, NPS_ENET_REG_TX_BUF,
+                                        get_unaligned(src));
+
        /* Write the length of the Frame */
        tx_ctrl.nt = length;