fsl_pq_mdio: Fix kernel oops during OF address translation

Old P1020RDB device trees were not specifing tbipa address for
MDIO nodes, which is now causing this kernel oops:

 ...
 eth2: TX BD ring size for Q[6]: 256
 eth2: TX BD ring size for Q[7]: 256
 Unable to handle kernel paging request for data at address 0x00000000
 Faulting instruction address: 0xc0015504
 Oops: Kernel access of bad area, sig: 11 [#1]
 ...
 NIP [c0015504] memcpy+0x3c/0x9c
 LR [c000a9f8] __of_translate_address+0xfc/0x21c
 Call Trace:
 [df839e00] [c000a94c] __of_translate_address+0x50/0x21c (unreliable)
 [df839e50] [c01a33e8] get_gfar_tbipa+0xb0/0xe0
 ...

The old device trees are buggy, though having a dead ethernet is
better than a dead kernel, so fix the issue by using of_iomap().

Also, a somewhat similar issue exist in the probe() routine, though
there the oops is only a possibility. Nonetheless, fix it too.

Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 6 deletions

diff --git a/drivers/net/fsl_pq_mdio.c b/drivers/net/fsl_pq_mdio.c
index d5160edf2fcf..3acac5f930c8 100644
--- a/drivers/net/fsl_pq_mdio.c
+++ b/drivers/net/fsl_pq_mdio.c
@@ -205,8 +205,6 @@ static int fsl_pq_mdio_find_free(struct mii_bus *new_bus)
 static u32 __iomem *get_gfar_tbipa(struct fsl_pq_mdio __iomem *regs, struct device_node *np)
 {
         struct gfar __iomem *enet_regs;
-        u32 __iomem *ioremap_tbipa;
-        u64 addr, size;
 
         /*
          * This is mildly evil, but so is our hardware for doing this.
@@ -220,9 +218,7 @@ static u32 __iomem *get_gfar_tbipa(struct fsl_pq_mdio __iomem *regs, struct devi
                 return &enet_regs->tbipa;
         } else if (of_device_is_compatible(np, "fsl,etsec2-mdio") ||
                         of_device_is_compatible(np, "fsl,etsec2-tbi")) {
-                addr = of_translate_address(np, of_get_address(np, 1, &size, NULL));
-                ioremap_tbipa = ioremap(addr, size);
-                return ioremap_tbipa;
+                return of_iomap(np, 1);
         } else
                 return NULL;
 }
@@ -279,6 +275,7 @@ static int fsl_pq_mdio_probe(struct of_device *ofdev,
         u32 __iomem *tbipa;
         struct mii_bus *new_bus;
         int tbiaddr = -1;
+        const u32 *addrp;
         u64 addr = 0, size = 0;
         int err = 0;
 
@@ -297,8 +294,19 @@ static int fsl_pq_mdio_probe(struct of_device *ofdev,
         new_bus->priv = priv;
         fsl_pq_mdio_bus_name(new_bus->id, np);
 
+        addrp = of_get_address(np, 0, &size, NULL);
+        if (!addrp) {
+                err = -EINVAL;
+                goto err_free_bus;
+        }
+
         /* Set the PHY base address */
-        addr = of_translate_address(np, of_get_address(np, 0, &size, NULL));
+        addr = of_translate_address(np, addrp);
+        if (addr == OF_BAD_ADDR) {
+                err = -EINVAL;
+                goto err_free_bus;
+        }
+
         map = ioremap(addr, size);
         if (!map) {
                 err = -ENOMEM;