diff --git a/sys/dev/usb/net/if_smsc.c b/sys/dev/usb/net/if_smsc.c index 84610c894f4d..e90b7dc0e9d5 100644 --- a/sys/dev/usb/net/if_smsc.c +++ b/sys/dev/usb/net/if_smsc.c @@ -119,11 +119,18 @@ __FBSDID("$FreeBSD$"); #include "miibus_if.h" +SYSCTL_NODE(_hw_usb, OID_AUTO, smsc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, + "USB smsc"); + +static bool smsc_rx_packet_batching = 1; + +SYSCTL_BOOL(_hw_usb_smsc, OID_AUTO, smsc_rx_packet_batching, CTLFLAG_RDTUN, + &smsc_rx_packet_batching, 0, + "Multiple frames per RX transaction. Increases throughput and latency"); + #ifdef USB_DEBUG static int smsc_debug = 0; -SYSCTL_NODE(_hw_usb, OID_AUTO, smsc, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, - "USB smsc"); SYSCTL_INT(_hw_usb_smsc, OID_AUTO, debug, CTLFLAG_RWTUN, &smsc_debug, 0, "Debug level"); #endif @@ -1377,7 +1384,9 @@ smsc_chip_init(struct smsc_softc *sc) * Burst capability is the number of URBs that can be in a burst of data/ * ethernet frames. */ - if (usbd_get_speed(sc->sc_ue.ue_udev) == USB_SPEED_HIGH) + if (!smsc_rx_packet_batching) + burst_cap = 0; + else if (usbd_get_speed(sc->sc_ue.ue_udev) == USB_SPEED_HIGH) burst_cap = 37; else burst_cap = 128; @@ -1404,7 +1413,8 @@ smsc_chip_init(struct smsc_softc *sc) /* The following setings are used for 'turbo mode', a.k.a multiple frames * per Rx transaction (again info taken form Linux driver). */ - reg_val |= (SMSC_HW_CFG_MEF | SMSC_HW_CFG_BCE); + if (smsc_rx_packet_batching) + reg_val |= (SMSC_HW_CFG_MEF | SMSC_HW_CFG_BCE); smsc_write_reg(sc, SMSC_HW_CFG, reg_val);