path: root/drivers/net/ethernet/rdc
diff options
authorFlorian Fainelli <florian@openwrt.org>2014-01-15 13:04:25 -0800
committerDavid S. Miller <davem@davemloft.net>2014-01-16 16:22:54 -0800
commit4f8d9f3ce0e52adf2cb4e0661f06ef8cfdc97cfe (patch)
tree0a897dd1a0f011b099e25a088a0ec82543cbbf52 /drivers/net/ethernet/rdc
parentxen-netfront: add support for IPv6 offloads (diff)
r6040: add delays in MDIO read/write polling loops
On newer and faster machines (Vortex X86DX) using the r6040 driver, it was noticed that the driver was returning an error during probing traced down to being the MDIO bus probing and the inability to complete a MDIO read operation in time. It turns out that the MDIO operations on these faster machines usually complete after ~2140 iterations which is bigger than 2048 (MAC_DEF_TIMEOUT) and results in spurious timeouts depending on the system load. Update r6040_phy_read() and r6040_phy_write() to include a 1 micro second delay in each busy-looping iteration of the loop which is a much safer operation than incrementing MAC_DEF_TIMEOUT. Reported-by: Nils Koehler <nils.koehler@ibt-interfaces.de> Reported-by: Daniel Goertzen <daniel.goertzen@gmail.com> Signed-off-by: Florian Fainelli <florian@openwrt.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/rdc')
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/net/ethernet/rdc/r6040.c b/drivers/net/ethernet/rdc/r6040.c
index 851376b7fc78..c6cd1d05f8ea 100644
--- a/drivers/net/ethernet/rdc/r6040.c
+++ b/drivers/net/ethernet/rdc/r6040.c
@@ -221,6 +221,7 @@ static int r6040_phy_read(void __iomem *ioaddr, int phy_addr, int reg)
cmd = ioread16(ioaddr + MMDIO);
if (!(cmd & MDIO_READ))
+ udelay(1);
if (limit < 0)
@@ -244,6 +245,7 @@ static int r6040_phy_write(void __iomem *ioaddr,
cmd = ioread16(ioaddr + MMDIO);
if (!(cmd & MDIO_WRITE))
+ udelay(1);
return (limit < 0) ? -ETIMEDOUT : 0;