Messages in this thread | | | Date | Tue, 23 May 2006 22:52:24 +0100 | From | "Daniel J Blueman" <> | Subject | Re: sky2 large MTU problems... |
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Hi Stephen,
I can confirm that I am unable to reproduce any of the problems I was seeing - it works as expected all the way up to the sky2 maximum MTU size of 9000. Fantastic!
Thanks again, Daniel
On 22/05/06, Stephen Hemminger <shemminger@osdl.org> wrote: > Try this, not completely baked yet though.. > > --- sky2.orig/drivers/net/sky2.c 2006-05-22 10:23:51.000000000 -0700 > +++ sky2/drivers/net/sky2.c 2006-05-22 11:30:50.000000000 -0700 > @@ -636,8 +636,10 @@ > TX_BACK_OFF_LIM(TX_BOF_LIM_DEF)); > > /* serial mode register */ > - reg = DATA_BLIND_VAL(DATA_BLIND_DEF) | > - GM_SMOD_VLAN_ENA | IPG_DATA_VAL(IPG_DATA_DEF); > + reg = DATA_BLIND_VAL(DATA_BLIND_DEF) |IPG_DATA_VAL(IPG_DATA_DEF); > +#ifdef SKY2_VLAN_TAG_USED > + reg |= GM_SMOD_VLAN_ENA; > +#endif > > if (hw->dev[port]->mtu > ETH_DATA_LEN) > reg |= GM_SMOD_JUMBO_ENA; > @@ -979,6 +981,7 @@ > struct sky2_hw *hw = sky2->hw; > unsigned rxq = rxqaddr[sky2->port]; > int i; > + unsigned thresh; > > sky2->rx_put = sky2->rx_next = 0; > sky2_qset(hw, rxq); > @@ -1003,9 +1006,22 @@ > sky2_rx_add(sky2, re->mapaddr); > } > > - /* Truncate oversize frames */ > - sky2_write16(hw, SK_REG(sky2->port, RX_GMF_TR_THR), sky2->rx_bufsize - 8); > - sky2_write32(hw, SK_REG(sky2->port, RX_GMF_CTRL_T), RX_TRUNC_ON); > + > + /* > + * The receiver hangs gets stuck if it receives frames larger than the > + * packet buffer. As a workaround, truncate oversize frames, but > + * truncate register is to 9 bits, so if you do jumbo frames > + * you better get the MTU right. > + */ > + thresh = (ALIGN(sky2->netdev->mtu + ETH_HLEN, 4) - 8)/4; > + > + if (thresh > 0x1ff) > + sky2_write32(hw, SK_REG(sky2->port, RX_GMF_CTRL_T), RX_TRUNC_OFF); > + else { > + sky2_write16(hw, SK_REG(sky2->port, RX_GMF_TR_THR), thresh); > + sky2_write32(hw, SK_REG(sky2->port, RX_GMF_CTRL_T), RX_TRUNC_ON); > + } > + > > /* Tell chip about available buffers */ > sky2_write16(hw, Y2_QADDR(rxq, PREF_UNIT_PUT_IDX), sky2->rx_put); > @@ -1754,7 +1770,7 @@ > */ > static inline unsigned sky2_buf_size(int mtu) > { > - return ALIGN(mtu + ETH_HLEN + VLAN_HLEN, 8) + 8; > + return ALIGN(mtu + ETH_HLEN, 8) + 8; > } > > static int sky2_change_mtu(struct net_device *dev, int new_mtu) > @@ -1792,8 +1808,10 @@ > > dev->mtu = new_mtu; > sky2->rx_bufsize = sky2_buf_size(new_mtu); > - mode = DATA_BLIND_VAL(DATA_BLIND_DEF) | > - GM_SMOD_VLAN_ENA | IPG_DATA_VAL(IPG_DATA_DEF); > + mode = DATA_BLIND_VAL(DATA_BLIND_DEF) |IPG_DATA_VAL(IPG_DATA_DEF); > +#ifdef SKY2_VLAN_TAG_USED > + mode |= GM_SMOD_VLAN_ENA; > +#endif > > if (dev->mtu > ETH_DATA_LEN) > mode |= GM_SMOD_JUMBO_ENA; > -- Daniel J Blueman - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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