mirror of https://gitee.com/openkylin/linux.git
ba7797119b
This fixes a less obvious error on one hand, and prevents futher similar errors by disambiguating and optimizing RxFCB indication, on the other hand. The error consists in NETIF_F_HW_VLAN_TX flag being used as an indication of Rx FCB insertion. This happened as soon gfar_uses_fcb(), which despite its name indicates Rx FCB insertion, started incorporating is_vlan_on(). is_vlan_on(), on the other hand, is also a misleading construct because we need to differentiate b/w hw VLAN extraction/VLEX (marked by VLAN_RX flag) and hw VLAN insertion/VLINS (VLAN_TX flag), which are different mechanisms using different types of FCBs. The hw spec for the RxFCB feature is as follows: In the case of RxBD rings, FCBs (Frame Control Block) are inserted by the eTSEC whenever RCTRL[PRSDEP] is set to a non-zero value. Only one FCB is inserted per frame (in the buffer pointed to by the RxBD with bit F set). TOE acceleration for receive is enabled for all rx frames in this case. This patch introduces priv->uses_rxfcb field to quickly signal RxFCB insertion in accordance with the specification above. The dependency on FSL_GIANFAR_DEV_HAS_TIMER was also eliminated as another source of confusion. The actual dependency is to priv->hwts_rx_en. Upon changing priv->hwts_rx_en via IOCTL, the gfar device is being restarted and on init_mac() the priv->hwts_rx_en flag determines RxFCB insertion, and rctrl is programmed accordingly. The patch takes care of this case too. Though maybe not as self documenting as the inlining version uses_fcb(), priv->uses_rxfcb has the main purpose to quickly signal, on the hot path, that the incoming frame has a *Rx* FCB block inserted which needs to be pulled out before passing the skb to the stack. This is a performance critical operation, it needs to happen fast, that's why uses_rxfcb is placed in the first cacheline of gfar_private. This is also why a cached rctrl cannot be used instead: 1) because we don't have 32 bits available in the first cacheline of gfar_priv (but only 16); 2) bit operations are expensive on the hot path. Signed-off-by: Claudiu Manoil <claudiu.manoil@freescale.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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fs_enet | ||
Kconfig | ||
Makefile | ||
fec.c | ||
fec.h | ||
fec_mpc52xx.c | ||
fec_mpc52xx.h | ||
fec_mpc52xx_phy.c | ||
fec_ptp.c | ||
fsl_pq_mdio.c | ||
gianfar.c | ||
gianfar.h | ||
gianfar_ethtool.c | ||
gianfar_ptp.c | ||
gianfar_sysfs.c | ||
ucc_geth.c | ||
ucc_geth.h | ||
ucc_geth_ethtool.c | ||
xgmac_mdio.c |