2015-05-04 07:53:10

by Harini Katakam

[permalink] [raw]
Subject: [net-next PATCH v2 3/3] net: macb: Add change_mtu callback with jumbo support

Add macb_change_mtu callback; if jumbo frame support is present allow
mtu size changes upto (jumbo max length allowed - headers).

Signed-off-by: Harini Katakam <[email protected]>
Reviewed-by: Punnaiah Choudary Kalluri <[email protected]>
---

v2:
Move constant definition.

---
drivers/net/ethernet/cadence/macb.c | 24 +++++++++++++++++++++++-
1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c
index a065283..e4a9c17 100644
--- a/drivers/net/ethernet/cadence/macb.c
+++ b/drivers/net/ethernet/cadence/macb.c
@@ -54,6 +54,8 @@
#define MACB_MAX_TX_LEN ((unsigned int)((1 << MACB_TX_FRMLEN_SIZE) - 1))
#define GEM_MAX_TX_LEN ((unsigned int)((1 << GEM_TX_FRMLEN_SIZE) - 1))

+#define GEM_MTU_MIN_SIZE 68
+
#define GEM_ZYNQMP_JUMBO_MAX 10240

/*
@@ -1857,6 +1859,26 @@ static int macb_close(struct net_device *dev)
return 0;
}

+static int macb_change_mtu(struct net_device *dev, int new_mtu)
+{
+ struct macb *bp = netdev_priv(dev);
+ u32 max_mtu;
+
+ if (netif_running(dev))
+ return -EBUSY;
+
+ max_mtu = ETH_DATA_LEN;
+ if (bp->isjumbo)
+ max_mtu = gem_readl(bp, JML) - ETH_HLEN - ETH_FCS_LEN;
+
+ if ((new_mtu > max_mtu) || (new_mtu < GEM_MTU_MIN_SIZE))
+ return -EINVAL;
+
+ dev->mtu = new_mtu;
+
+ return 0;
+}
+
static void gem_update_stats(struct macb *bp)
{
int i;
@@ -2133,7 +2155,7 @@ static const struct net_device_ops macb_netdev_ops = {
.ndo_get_stats = macb_get_stats,
.ndo_do_ioctl = macb_ioctl,
.ndo_validate_addr = eth_validate_addr,
- .ndo_change_mtu = eth_change_mtu,
+ .ndo_change_mtu = macb_change_mtu,
.ndo_set_mac_address = eth_mac_addr,
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_poll_controller = macb_poll_controller,
--
1.7.9.5