Introduce if_mgb driver for Microchip LAN743x PCIe NIC

The Microchip LAN7430 is a PCIe 10/100/1000 Ethernet MAC with integrated
PHY, and the LAN7431 is a MAC with RGMII interface.

To be connected to the build after further testing and review.
Committing now so that changes like r354345 (adding a common
ETHER_IS_ZERO macro) will update this driver too.

Submitted by:	Gerald ND Aryeetey <aryeeteygerald_rogers.com>
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20079

3 files changed, 1980 insertions, 0 deletions

diff --git a/sys/dev/mgb/if_mgb.c b/sys/dev/mgb/if_mgb.c
new file mode 100644
index 000000000000..1608abac97ba
--- /dev/null
+++ b/sys/dev/mgb/if_mgb.c
@@ -0,0 +1,1634 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 The FreeBSD Foundation, Inc.
+ *
+ * This driver was written by Gerald ND Aryeetey <gndaryee@uwaterloo.ca>
+ * under sponsorship from the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * Microchip LAN7430/LAN7431 PCIe to Gigabit Ethernet Controller driver.
+ *
+ * Product information:
+ * LAN7430 https://www.microchip.com/wwwproducts/en/LAN7430
+ *   - Integrated IEEE 802.3 compliant PHY
+ * LAN7431 https://www.microchip.com/wwwproducts/en/LAN7431
+ *   - RGMII Interface
+ *
+ * This driver uses the iflib interface and the default 'ukphy' PHY driver.
+ *
+ * UNIMPLEMENTED FEATURES
+ * ----------------------
+ * A number of features supported by LAN743X device are not yet implemented in
+ * this driver:
+ *
+ * - Multiple (up to 4) RX queues support
+ *   - Just needs to remove asserts and malloc multiple `rx_ring_data`
+ *     structs based on ncpus.
+ * - RX/TX Checksum Offloading support
+ * - VLAN support
+ * - Recieve Packet Filtering (Multicast Perfect/Hash Address) support
+ * - Wake on LAN (WoL) support
+ * - TX LSO support
+ * - Recieve Side Scaling (RSS) support
+ * - Debugging Capabilities:
+ *   - Could include MAC statistics and
+ *     error status registers in sysctl.
+ */
+
+#include <sys/param.h>
+#include <sys/bus.h>
+#include <sys/endian.h>
+#include <sys/kdb.h>
+#include <sys/kernel.h>
+#include <sys/module.h>
+#include <sys/rman.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
+#include <machine/bus.h>
+#include <machine/resource.h>
+
+#include <net/ethernet.h>
+#include <net/if.h>
+#include <net/if_var.h>
+#include <net/if_types.h>
+#include <net/if_media.h>
+#include <net/iflib.h>
+
+#include <dev/mgb/if_mgb.h>
+#include <dev/mii/mii.h>
+#include <dev/mii/miivar.h>
+#include <dev/pci/pcireg.h>
+#include <dev/pci/pcivar.h>
+
+#include "ifdi_if.h"
+#include "miibus_if.h"
+
+static pci_vendor_info_t mgb_vendor_info_array[] = {
+	PVID(MGB_MICROCHIP_VENDOR_ID, MGB_LAN7430_DEVICE_ID,
+	    "Microchip LAN7430 PCIe Gigabit Ethernet Controller"),
+	PVID(MGB_MICROCHIP_VENDOR_ID, MGB_LAN7431_DEVICE_ID,
+	    "Microchip LAN7431 PCIe Gigabit Ethernet Controller"),
+	PVID_END
+};
+
+/* Device methods */
+static device_register_t		mgb_register;
+
+/* IFLIB methods */
+static ifdi_attach_pre_t		mgb_attach_pre;
+static ifdi_attach_post_t		mgb_attach_post;
+static ifdi_detach_t			mgb_detach;
+
+static ifdi_tx_queues_alloc_t		mgb_tx_queues_alloc;
+static ifdi_rx_queues_alloc_t		mgb_rx_queues_alloc;
+static ifdi_queues_free_t		mgb_queues_free;
+
+static ifdi_init_t			mgb_init;
+static ifdi_stop_t			mgb_stop;
+
+static ifdi_msix_intr_assign_t		mgb_msix_intr_assign;
+static ifdi_tx_queue_intr_enable_t	mgb_tx_queue_intr_enable;
+static ifdi_rx_queue_intr_enable_t	mgb_rx_queue_intr_enable;
+static ifdi_intr_enable_t		mgb_intr_enable_all;
+static ifdi_intr_disable_t		mgb_intr_disable_all;
+
+/* IFLIB_TXRX methods */
+static int				mgb_isc_txd_encap(void *,
+					    if_pkt_info_t);
+static void				mgb_isc_txd_flush(void *,
+					    uint16_t, qidx_t);
+static int				mgb_isc_txd_credits_update(void *,
+					    uint16_t, bool);
+static int				mgb_isc_rxd_available(void *,
+					    uint16_t, qidx_t, qidx_t);
+static int				mgb_isc_rxd_pkt_get(void *,
+					    if_rxd_info_t);
+static void				mgb_isc_rxd_refill(void *,
+					    if_rxd_update_t);
+static void				mgb_isc_rxd_flush(void *,
+					    uint16_t, uint8_t, qidx_t);
+
+/* Interrupts */
+static driver_filter_t			mgb_legacy_intr;
+static driver_filter_t			mgb_admin_intr;
+static driver_filter_t			mgb_rxq_intr;
+static bool				mgb_intr_test(struct mgb_softc *);
+
+/* MII methods */
+static miibus_readreg_t			mgb_miibus_readreg;
+static miibus_writereg_t		mgb_miibus_writereg;
+static miibus_linkchg_t			mgb_miibus_linkchg;
+static miibus_statchg_t			mgb_miibus_statchg;
+
+static int				mgb_media_change(if_t);
+static void				mgb_media_status(if_t,
+					    struct ifmediareq *);
+
+/* Helper/Test functions */
+static int				mgb_test_bar(struct mgb_softc *);
+static int				mgb_alloc_regs(struct mgb_softc *);
+static int				mgb_release_regs(struct mgb_softc *);
+
+static void				mgb_get_ethaddr(struct mgb_softc *,
+					    struct ether_addr *);
+
+static int				mgb_wait_for_bits(struct mgb_softc *,
+					    int, int, int);
+
+/* H/W init, reset and teardown helpers */
+static int				mgb_hw_init(struct mgb_softc *);
+static int				mgb_hw_teardown(struct mgb_softc *);
+static int				mgb_hw_reset(struct mgb_softc *);
+static int				mgb_mac_init(struct mgb_softc *);
+static int				mgb_dmac_reset(struct mgb_softc *);
+static int				mgb_phy_reset(struct mgb_softc *);
+
+static int				mgb_dma_init(struct mgb_softc *);
+static int				mgb_dma_tx_ring_init(struct mgb_softc *,
+					    int);
+static int				mgb_dma_rx_ring_init(struct mgb_softc *,
+					    int);
+
+static int				mgb_dmac_control(struct mgb_softc *,
+					    int, int, enum mgb_dmac_cmd);
+static int				mgb_fct_control(struct mgb_softc *,
+					    int, int, enum mgb_fct_cmd);
+
+/*********************************************************************
+ *  FreeBSD Device Interface Entry Points
+ *********************************************************************/
+
+static device_method_t mgb_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_register,	mgb_register),
+	DEVMETHOD(device_probe,		iflib_device_probe),
+	DEVMETHOD(device_attach,	iflib_device_attach),
+	DEVMETHOD(device_detach,	iflib_device_detach),
+	DEVMETHOD(device_shutdown,	iflib_device_shutdown),
+	DEVMETHOD(device_suspend,	iflib_device_suspend),
+	DEVMETHOD(device_resume,	iflib_device_resume),
+
+	/* MII Interface */
+	DEVMETHOD(miibus_readreg,	mgb_miibus_readreg),
+	DEVMETHOD(miibus_writereg,	mgb_miibus_writereg),
+	DEVMETHOD(miibus_linkchg,	mgb_miibus_linkchg),
+	DEVMETHOD(miibus_statchg,	mgb_miibus_statchg),
+
+	DEVMETHOD_END
+};
+
+static driver_t mgb_driver = {
+	"mgb", mgb_methods, sizeof(struct mgb_softc)
+};
+
+devclass_t mgb_devclass;
+DRIVER_MODULE(mgb, pci, mgb_driver, mgb_devclass, NULL, NULL);
+IFLIB_PNP_INFO(pci, mgb, mgb_vendor_info_array);
+MODULE_VERSION(mgb, 1);
+
+#if 0 /* MIIBUS_DEBUG */
+/* If MIIBUS debug stuff is in attach then order matters. Use below instead. */
+DRIVER_MODULE_ORDERED(miibus, mgb, miibus_driver, miibus_devclass, NULL, NULL,
+    SI_ORDER_ANY);
+#endif /* MIIBUS_DEBUG */
+DRIVER_MODULE(miibus, mgb, miibus_driver, miibus_devclass, NULL, NULL);
+
+MODULE_DEPEND(mgb, pci, 1, 1, 1);
+MODULE_DEPEND(mgb, ether, 1, 1, 1);
+MODULE_DEPEND(mgb, miibus, 1, 1, 1);
+MODULE_DEPEND(mgb, iflib, 1, 1, 1);
+
+static device_method_t mgb_iflib_methods[] = {
+	DEVMETHOD(ifdi_attach_pre, mgb_attach_pre),
+	DEVMETHOD(ifdi_attach_post, mgb_attach_post),
+	DEVMETHOD(ifdi_detach, mgb_detach),
+
+	DEVMETHOD(ifdi_init, mgb_init),
+	DEVMETHOD(ifdi_stop, mgb_stop),
+
+	DEVMETHOD(ifdi_tx_queues_alloc, mgb_tx_queues_alloc),
+	DEVMETHOD(ifdi_rx_queues_alloc, mgb_rx_queues_alloc),
+	DEVMETHOD(ifdi_queues_free, mgb_queues_free),
+
+	DEVMETHOD(ifdi_msix_intr_assign, mgb_msix_intr_assign),
+	DEVMETHOD(ifdi_tx_queue_intr_enable, mgb_tx_queue_intr_enable),
+	DEVMETHOD(ifdi_rx_queue_intr_enable, mgb_rx_queue_intr_enable),
+	DEVMETHOD(ifdi_intr_enable, mgb_intr_enable_all),
+	DEVMETHOD(ifdi_intr_disable, mgb_intr_disable_all),
+
+
+#if 0 /* Not yet implemented IFLIB methods */
+	/*
+	 * Set multicast addresses, mtu and promiscuous mode
+	 */
+	DEVMETHOD(ifdi_multi_set, mgb_multi_set),
+	DEVMETHOD(ifdi_mtu_set, mgb_mtu_set),
+	DEVMETHOD(ifdi_promisc_set, mgb_promisc_set),
+
+	/*
+	 * Needed for VLAN support
+	 */
+	DEVMETHOD(ifdi_vlan_register, mgb_vlan_register),
+	DEVMETHOD(ifdi_vlan_unregister, mgb_vlan_unregister),
+
+	/*
+	 * Needed for WOL support
+	 * at the very least.
+	 */
+	DEVMETHOD(ifdi_shutdown, mgb_shutdown),
+	DEVMETHOD(ifdi_suspend, mgb_suspend),
+	DEVMETHOD(ifdi_resume, mgb_resume),
+#endif /* UNUSED_IFLIB_METHODS */
+	DEVMETHOD_END
+};
+
+static driver_t mgb_iflib_driver = {
+	"mgb", mgb_iflib_methods, sizeof(struct mgb_softc)
+};
+
+struct if_txrx mgb_txrx  = {
+	.ift_txd_encap = mgb_isc_txd_encap,
+	.ift_txd_flush = mgb_isc_txd_flush,
+	.ift_txd_credits_update = mgb_isc_txd_credits_update,
+	.ift_rxd_available = mgb_isc_rxd_available,
+	.ift_rxd_pkt_get = mgb_isc_rxd_pkt_get,
+	.ift_rxd_refill = mgb_isc_rxd_refill,
+	.ift_rxd_flush = mgb_isc_rxd_flush,
+
+	.ift_legacy_intr = mgb_legacy_intr
+};
+
+struct if_shared_ctx mgb_sctx_init = {
+	.isc_magic = IFLIB_MAGIC,
+
+	.isc_q_align = PAGE_SIZE,
+	.isc_admin_intrcnt = 1,
+	.isc_flags = IFLIB_DRIVER_MEDIA /* | IFLIB_HAS_RXCQ | IFLIB_HAS_TXCQ*/,
+
+	.isc_vendor_info = mgb_vendor_info_array,
+	.isc_driver_version = "1",
+	.isc_driver = &mgb_iflib_driver,
+	/* 2 queues per set for TX and RX (ring queue, head writeback queue) */
+	.isc_ntxqs = 2,
+
+	.isc_tx_maxsize = MGB_DMA_MAXSEGS  * MCLBYTES,
+	/* .isc_tx_nsegments = MGB_DMA_MAXSEGS, */
+	.isc_tx_maxsegsize = MCLBYTES,
+
+	.isc_ntxd_min = {1, 1}, /* Will want to make this bigger */
+	.isc_ntxd_max = {MGB_DMA_RING_SIZE, 1},
+	.isc_ntxd_default = {MGB_DMA_RING_SIZE, 1},
+
+	.isc_nrxqs = 2,
+
+	.isc_rx_maxsize = MCLBYTES,
+	.isc_rx_nsegments = 1,
+	.isc_rx_maxsegsize = MCLBYTES,
+
+	.isc_nrxd_min = {1, 1}, /* Will want to make this bigger */
+	.isc_nrxd_max = {MGB_DMA_RING_SIZE, 1},
+	.isc_nrxd_default = {MGB_DMA_RING_SIZE, 1},
+
+	.isc_nfl = 1, /*one free list since there is only one queue */
+#if 0 /* UNUSED_CTX */
+
+	.isc_tso_maxsize = MGB_TSO_MAXSIZE + sizeof(struct ether_vlan_header),
+	.isc_tso_maxsegsize = MGB_TX_MAXSEGSIZE,
+#endif /* UNUSED_CTX */
+};
+
+/*********************************************************************/
+
+
+static void *
+mgb_register(device_t dev)
+{
+
+	return (&mgb_sctx_init);
+}
+
+static int
+mgb_attach_pre(if_ctx_t ctx)
+{
+	struct mgb_softc *sc;
+	if_softc_ctx_t scctx;
+	int error, phyaddr, rid;
+	struct ether_addr hwaddr;
+	struct mii_data *miid;
+
+	sc = iflib_get_softc(ctx);
+	sc->ctx = ctx;
+	sc->dev = iflib_get_dev(ctx);
+	scctx = iflib_get_softc_ctx(ctx);
+
+	/* IFLIB required setup */
+	scctx->isc_txrx = &mgb_txrx;
+	scctx->isc_tx_nsegments = MGB_DMA_MAXSEGS;
+	/* Ring desc queues */
+	scctx->isc_txqsizes[0] = sizeof(struct mgb_ring_desc) *
+	    scctx->isc_ntxd[0];
+	scctx->isc_rxqsizes[0] = sizeof(struct mgb_ring_desc) *
+	    scctx->isc_nrxd[0];
+
+	/* Head WB queues */
+	scctx->isc_txqsizes[1] = sizeof(uint32_t) * scctx->isc_ntxd[1];
+	scctx->isc_rxqsizes[1] = sizeof(uint32_t) * scctx->isc_nrxd[1];
+
+	/* XXX: Must have 1 txqset, but can have up to 4 rxqsets */
+	scctx->isc_nrxqsets = 1;
+	scctx->isc_ntxqsets = 1;
+
+	/* scctx->isc_tx_csum_flags = (CSUM_TCP | CSUM_UDP) |
+	    (CSUM_TCP_IPV6 | CSUM_UDP_IPV6) | CSUM_TSO */
+	scctx->isc_tx_csum_flags = 0;
+	scctx->isc_capabilities = scctx->isc_capenable = 0;
+#if 0
+	/*
+	 * CSUM, TSO and VLAN support are TBD
+	 */
+	    IFCAP_TXCSUM | IFCAP_TXCSUM_IPV6 |
+	    IFCAP_TSO4 | IFCAP_TSO6 |
+	    IFCAP_RXCSUM | IFCAP_RXCSUM_IPV6 |
+	    IFCAP_VLAN_MTU | IFCAP_VLAN_HWTAGGING |
+	    IFCAP_VLAN_HWCSUM | IFCAP_VLAN_HWTSO |
+	    IFCAP_JUMBO_MTU;
+	scctx->isc_capabilities |= IFCAP_LRO | IFCAP_VLAN_HWFILTER;
+#endif
+
+	/* get the BAR */
+	error = mgb_alloc_regs(sc);
+	if (error != 0) {
+		device_printf(sc->dev,
+		    "Unable to allocate bus resource: registers.\n");
+		goto fail;
+	}
+
+	error = mgb_test_bar(sc);
+	if (error != 0)
+		goto fail;
+
+	error = mgb_hw_init(sc);
+	if (error != 0) {
+		device_printf(sc->dev,
+		    "MGB device init failed. (err: %d)\n", error);
+		goto fail;
+	}
+
+	switch (pci_get_device(sc->dev))
+	{
+	case MGB_LAN7430_DEVICE_ID:
+		phyaddr = 1;
+		break;
+	case MGB_LAN7431_DEVICE_ID:
+	default:
+		phyaddr = MII_PHY_ANY;
+		break;
+	}
+
+	/* XXX: Would be nice(r) if locked methods were here */
+	error = mii_attach(sc->dev, &sc->miibus, iflib_get_ifp(ctx),
+	    mgb_media_change, mgb_media_status,
+	    BMSR_DEFCAPMASK, phyaddr, MII_OFFSET_ANY, MIIF_DOPAUSE);
+	if (error != 0) {
+		device_printf(sc->dev, "Failed to attach MII interface\n");
+		goto fail;
+	}
+
+	miid = device_get_softc(sc->miibus);
+	scctx->isc_media = &miid->mii_media;
+
+	scctx->isc_msix_bar = pci_msix_table_bar(sc->dev);
+	/** Setup PBA BAR **/
+	rid = pci_msix_pba_bar(sc->dev);
+	if (rid != scctx->isc_msix_bar) {
+		sc->pba = bus_alloc_resource_any(sc->dev, SYS_RES_MEMORY,
+		    &rid, RF_ACTIVE);
+		if (sc->pba == NULL) {
+			error = ENXIO;
+			device_printf(sc->dev, "Failed to setup PBA BAR\n");
+			goto fail;
+		}
+	}
+
+	mgb_get_ethaddr(sc, &hwaddr);
+	if (ETHER_IS_BROADCAST(hwaddr.octet) ||
+	    ETHER_IS_MULTICAST(hwaddr.octet) ||
+	    ETHER_IS_ZERO(hwaddr.octet))
+		ether_gen_addr(iflib_get_ifp(ctx), &hwaddr);
+
+	/*
+	 * XXX: if the MAC address was generated the linux driver
+	 * writes it back to the device.
+	 */
+	iflib_set_mac(ctx, hwaddr.octet);
+
+	/* Map all vectors to vector 0 (admin interrupts) by default. */
+	CSR_WRITE_REG(sc, MGB_INTR_VEC_RX_MAP, 0);
+	CSR_WRITE_REG(sc, MGB_INTR_VEC_TX_MAP, 0);
+	CSR_WRITE_REG(sc, MGB_INTR_VEC_OTHER_MAP, 0);
+
+	return (0);
+
+fail:
+	mgb_detach(ctx);
+	return (error);
+}
+
+static int
+mgb_attach_post(if_ctx_t ctx)
+{
+	struct mgb_softc *sc;
+
+	sc = iflib_get_softc(ctx);
+
+	device_printf(sc->dev, "Interrupt test: %s\n",
+	    (mgb_intr_test(sc) ? "PASS" : "FAIL"));
+
+	return (0);
+}
+
+static int
+mgb_detach(if_ctx_t ctx)
+{
+	struct mgb_softc *sc;
+	int error;
+
+	sc = iflib_get_softc(ctx);
+
+	/* XXX: Should report errors but still detach everything. */
+	error = mgb_hw_teardown(sc);
+
+	/* Release IRQs */
+	iflib_irq_free(ctx, &sc->rx_irq);
+	iflib_irq_free(ctx, &sc->admin_irq);
+
+	if (sc->miibus != NULL)
+		device_delete_child(sc->dev, sc->miibus);
+
+	if (sc->pba != NULL)
+		error = bus_release_resource(sc->dev, SYS_RES_MEMORY,
+		    rman_get_rid(sc->pba), sc->pba);
+	sc->pba = NULL;
+
+	error = mgb_release_regs(sc);
+
+	return (error);
+}
+
+static int
+mgb_media_change(if_t ifp)
+{
+	struct mii_data *miid;
+	struct mii_softc *miisc;
+	struct mgb_softc *sc;
+	if_ctx_t ctx;
+	int needs_reset;
+
+	ctx = if_getsoftc(ifp);
+	sc = iflib_get_softc(ctx);
+	miid = device_get_softc(sc->miibus);
+	LIST_FOREACH(miisc, &miid->mii_phys, mii_list)
+		PHY_RESET(miisc);
+
+	needs_reset = mii_mediachg(miid);
+	if (needs_reset != 0)
+		ifp->if_init(ctx);
+	return (needs_reset);
+}
+
+static void
+mgb_media_status(if_t ifp, struct ifmediareq *ifmr)
+{
+	struct mgb_softc *sc;
+	struct mii_data *miid;
+
+	sc = iflib_get_softc(if_getsoftc(ifp));
+	miid = device_get_softc(sc->miibus);
+	if ((if_getflags(ifp) & IFF_UP) == 0)
+		return;
+
+	mii_pollstat(miid);
+	ifmr->ifm_active = miid->mii_media_active;
+	ifmr->ifm_status = miid->mii_media_status;
+}
+
+static int
+mgb_tx_queues_alloc(if_ctx_t ctx, caddr_t *vaddrs, uint64_t *paddrs, int ntxqs,
+    int ntxqsets)
+{
+	struct mgb_softc *sc;
+	struct mgb_ring_data *rdata;
+	int q;
+
+	sc = iflib_get_softc(ctx);
+	KASSERT(ntxqsets == 1, ("ntxqsets = %d", ntxqsets));
+	rdata = &sc->tx_ring_data;
+	for (q = 0; q < ntxqsets; q++) {
+		KASSERT(ntxqs == 2, ("ntxqs = %d", ntxqs));
+		/* Ring */
+		rdata->ring = (struct mgb_ring_desc *) vaddrs[q * ntxqs + 0];
+		rdata->ring_bus_addr = paddrs[q * ntxqs + 0];
+
+		/* Head WB */
+		rdata->head_wb = (uint32_t *) vaddrs[q * ntxqs + 1];
+		rdata->head_wb_bus_addr = paddrs[q * ntxqs + 1];
+	}
+	return 0;
+}
+
+static int
+mgb_rx_queues_alloc(if_ctx_t ctx, caddr_t *vaddrs, uint64_t *paddrs, int nrxqs,
+    int nrxqsets)
+{
+	struct mgb_softc *sc;
+	struct mgb_ring_data *rdata;
+	int q;
+
+	sc = iflib_get_softc(ctx);
+	KASSERT(nrxqsets == 1, ("nrxqsets = %d", nrxqsets));
+	rdata = &sc->rx_ring_data;
+	for (q = 0; q < nrxqsets; q++) {
+		KASSERT(nrxqs == 2, ("nrxqs = %d", nrxqs));
+		/* Ring */
+		rdata->ring = (struct mgb_ring_desc *) vaddrs[q * nrxqs + 0];
+		rdata->ring_bus_addr = paddrs[q * nrxqs + 0];
+
+		/* Head WB */
+		rdata->head_wb = (uint32_t *) vaddrs[q * nrxqs + 1];
+		rdata->head_wb_bus_addr = paddrs[q * nrxqs + 1];
+	}
+	return 0;
+}
+
+static void
+mgb_queues_free(if_ctx_t ctx)
+{
+	struct mgb_softc *sc;
+
+	sc = iflib_get_softc(ctx);
+
+	memset(&sc->rx_ring_data, 0, sizeof(struct mgb_ring_data));
+	memset(&sc->tx_ring_data, 0, sizeof(struct mgb_ring_data));
+}
+
+static void
+mgb_init(if_ctx_t ctx)
+{
+	struct mgb_softc *sc;
+	struct mii_data *miid;
+	int error;
+
+	sc = iflib_get_softc(ctx);
+	miid = device_get_softc(sc->miibus);
+	device_printf(sc->dev, "running init ...\n");
+
+	mgb_dma_init(sc);
+
+	/* XXX: Turn off perfect filtering, turn on (broad|multi|uni)cast rx */
+	CSR_CLEAR_REG(sc, MGB_RFE_CTL, MGB_RFE_ALLOW_PERFECT_FILTER);
+	CSR_UPDATE_REG(sc, MGB_RFE_CTL,
+	    MGB_RFE_ALLOW_BROADCAST |
+	    MGB_RFE_ALLOW_UNICAST |
+	    MGB_RFE_ALLOW_UNICAST);
+
+	error = mii_mediachg(miid);
+	KASSERT(!error, ("mii_mediachg returned: %d", error));
+}
+
+#ifdef DEBUG
+static void
+mgb_dump_some_stats(struct mgb_softc *sc)
+{
+	int i;
+	int first_stat = 0x1200;
+	int last_stat = 0x12FC;
+
+	for (i = first_stat; i <= last_stat; i += 4)
+		if (CSR_READ_REG(sc, i) != 0)
+			device_printf(sc->dev, "0x%04x: 0x%08x\n", i,
+			    CSR_READ_REG(sc, i));
+	char *stat_names[] = {
+		"MAC_ERR_STS ",
+		"FCT_INT_STS ",
+		"DMAC_CFG ",
+		"DMAC_CMD ",
+		"DMAC_INT_STS ",
+		"DMAC_INT_EN ",
+		"DMAC_RX_ERR_STS0 ",
+		"DMAC_RX_ERR_STS1 ",
+		"DMAC_RX_ERR_STS2 ",
+		"DMAC_RX_ERR_STS3 ",
+		"INT_STS ",
+		"INT_EN ",
+		"INT_VEC_EN ",
+		"INT_VEC_MAP0 ",
+		"INT_VEC_MAP1 ",
+		"INT_VEC_MAP2 ",
+		"TX_HEAD0",
+		"TX_TAIL0",
+		"DMAC_TX_ERR_STS0 ",
+		NULL
+	};
+	int stats[] = {
+		0x114,
+		0xA0,
+		0xC00,
+		0xC0C,
+		0xC10,
+		0xC14,
+		0xC60,
+		0xCA0,
+		0xCE0,
+		0xD20,
+		0x780,
+		0x788,
+		0x794,
+		0x7A0,
+		0x7A4,
+		0x780,
+		0xD58,
+		0xD5C,
+		0xD60,
+		0x0
+	};
+	i = 0;
+	printf("==============================\n");
+	while (stats[i++])
+		device_printf(sc->dev, "%s at offset 0x%04x = 0x%08x\n",
+		    stat_names[i - 1], stats[i - 1],
+		    CSR_READ_REG(sc, stats[i - 1]));
+	printf("==== TX RING DESCS ====\n");
+	for (i = 0; i < MGB_DMA_RING_SIZE; i++)
+		device_printf(sc->dev, "ring[%d].data0=0x%08x\n"
+		    "ring[%d].data1=0x%08x\n"
+		    "ring[%d].data2=0x%08x\n"
+		    "ring[%d].data3=0x%08x\n",
+		    i, sc->tx_ring_data.ring[i].ctl,
+		    i, sc->tx_ring_data.ring[i].addr.low,
+		    i, sc->tx_ring_data.ring[i].addr.high,
+		    i, sc->tx_ring_data.ring[i].sts);
+	device_printf(sc->dev, "==== DUMP_TX_DMA_RAM ====\n");
+	int i;
+	CSR_WRITE_REG(sc, 0x24, 0xF); // DP_SEL & TX_RAM_0
+	for (i = 0; i < 128; i++) {
+		CSR_WRITE_REG(sc, 0x2C, i); // DP_ADDR
+
+		CSR_WRITE_REG(sc, 0x28, 0); // DP_CMD
+
+		while ((CSR_READ_REG(sc, 0x24) & 0x80000000) == 0) // DP_SEL & READY
+			DELAY(1000);
+
+		device_printf(sc->dev, "DMAC_TX_RAM_0[%u]=%08x\n", i,
+		    CSR_READ_REG(sc, 0x30)); // DP_DATA
+	}
+}
+#endif
+
+static void
+mgb_stop(if_ctx_t ctx)
+{
+	struct mgb_softc *sc ;
+	if_softc_ctx_t scctx;
+	int i;
+
+	sc = iflib_get_softc(ctx);
+	scctx = iflib_get_softc_ctx(ctx);
+
+	/* XXX: Could potentially timeout */
+	for (i = 0; i < scctx->isc_nrxqsets; i++) {
+		mgb_dmac_control(sc, MGB_DMAC_RX_START, 0, DMAC_STOP);
+		mgb_fct_control(sc, MGB_FCT_RX_CTL, 0, FCT_DISABLE);
+	}
+	for (i = 0; i < scctx->isc_ntxqsets; i++) {
+		mgb_dmac_control(sc, MGB_DMAC_TX_START, 0, DMAC_STOP);
+		mgb_fct_control(sc, MGB_FCT_TX_CTL, 0, FCT_DISABLE);
+	}
+}
+
+static int
+mgb_legacy_intr(void *xsc)
+{
+	struct mgb_softc *sc;
+
+	sc = xsc;
+	iflib_admin_intr_deferred(sc->ctx);
+	return (FILTER_HANDLED);
+}
+
+static int
+mgb_rxq_intr(void *xsc)
+{
+	struct mgb_softc *sc;
+	if_softc_ctx_t scctx;
+	uint32_t intr_sts, intr_en;
+	int qidx;
+
+	sc = xsc;
+	scctx = iflib_get_softc_ctx(sc->ctx);
+
+	intr_sts = CSR_READ_REG(sc, MGB_INTR_STS);
+	intr_en = CSR_READ_REG(sc, MGB_INTR_ENBL_SET);
+	intr_sts &= intr_en;
+
+	for (qidx = 0; qidx < scctx->isc_nrxqsets; qidx++) {
+		if ((intr_sts & MGB_INTR_STS_RX(qidx))){
+			CSR_WRITE_REG(sc, MGB_INTR_ENBL_CLR,
+			    MGB_INTR_STS_RX(qidx));
+			CSR_WRITE_REG(sc, MGB_INTR_STS, MGB_INTR_STS_RX(qidx));
+		}
+	}
+	return (FILTER_SCHEDULE_THREAD);
+}
+
+static int
+mgb_admin_intr(void *xsc)
+{
+	struct mgb_softc *sc;
+	if_softc_ctx_t scctx;
+	uint32_t intr_sts, intr_en;
+	int qidx;
+
+	sc = xsc;
+	scctx = iflib_get_softc_ctx(sc->ctx);
+
+	intr_sts = CSR_READ_REG(sc, MGB_INTR_STS);
+	intr_en = CSR_READ_REG(sc, MGB_INTR_ENBL_SET);
+	intr_sts &= intr_en;
+
+	/*
+	 * NOTE: Debugging printfs here
+	 * will likely cause interrupt test failure.
+	 */
+
+	/* TODO: shouldn't continue if suspended */
+	if ((intr_sts & MGB_INTR_STS_ANY) == 0)
+	{
+		device_printf(sc->dev, "non-mgb interrupt triggered.\n");
+		return (FILTER_SCHEDULE_THREAD);
+	}
+	if ((intr_sts &  MGB_INTR_STS_TEST) != 0)
+	{
+		sc->isr_test_flag = true;
+		CSR_WRITE_REG(sc, MGB_INTR_STS, MGB_INTR_STS_TEST);
+		return (FILTER_HANDLED);
+	}
+	if ((intr_sts & MGB_INTR_STS_RX_ANY) != 0)
+	{
+		for (qidx = 0; qidx < scctx->isc_nrxqsets; qidx++) {
+			if ((intr_sts & MGB_INTR_STS_RX(qidx))){
+				iflib_rx_intr_deferred(sc->ctx, qidx);
+			}
+		}
+		return (FILTER_HANDLED);
+	}
+	/* XXX: TX interrupts should not occur */
+	if ((intr_sts & MGB_INTR_STS_TX_ANY) != 0)
+	{
+		for (qidx = 0; qidx < scctx->isc_ntxqsets; qidx++) {
+			if ((intr_sts & MGB_INTR_STS_RX(qidx))) {
+				/* clear the interrupt sts and run handler */
+				CSR_WRITE_REG(sc, MGB_INTR_ENBL_CLR,
+				    MGB_INTR_STS_TX(qidx));
+				CSR_WRITE_REG(sc, MGB_INTR_STS,
+				    MGB_INTR_STS_TX(qidx));
+				iflib_tx_intr_deferred(sc->ctx, qidx);
+			}
+		}
+		return (FILTER_HANDLED);
+	}
+
+	return (FILTER_SCHEDULE_THREAD);
+}
+
+static int
+mgb_msix_intr_assign(if_ctx_t ctx, int msix)
+{
+	struct mgb_softc *sc;
+	if_softc_ctx_t scctx;
+	int error, i, vectorid;
+	char irq_name[16];
+
+	sc = iflib_get_softc(ctx);
+	scctx = iflib_get_softc_ctx(ctx);
+
+	KASSERT(scctx->isc_nrxqsets == 1 && scctx->isc_ntxqsets == 1,
+	    ("num rxqsets/txqsets != 1 "));
+
+	/*
+	 * First vector should be admin interrupts, others vectors are TX/RX
+	 *
+	 * RIDs start at 1, and vector ids start at 0.
+	 */
+	vectorid = 0;
+	error = iflib_irq_alloc_generic(ctx, &sc->admin_irq, vectorid + 1,
+	    IFLIB_INTR_ADMIN, mgb_admin_intr, sc, 0, "admin");
+	if (error) {
+		device_printf(sc->dev,
+		    "Failed to register admin interrupt handler\n");
+		return (error);
+	}
+
+	for (i = 0; i < scctx->isc_nrxqsets; i++) {
+		vectorid++;
+		snprintf(irq_name, sizeof(irq_name), "rxq%d", i);
+		error = iflib_irq_alloc_generic(ctx, &sc->rx_irq, vectorid + 1,
+		    IFLIB_INTR_RX, mgb_rxq_intr, sc, i, irq_name);
+		if (error) {
+			device_printf(sc->dev,
+			    "Failed to register rxq %d interrupt handler\n", i);
+			return (error);
+		}
+		CSR_UPDATE_REG(sc, MGB_INTR_VEC_RX_MAP,
+		    MGB_INTR_VEC_MAP(vectorid, i));
+	}
+
+	/* Not actually mapping hw TX interrupts ... */
+	for (i = 0; i < scctx->isc_ntxqsets; i++) {
+		snprintf(irq_name, sizeof(irq_name), "txq%d", i);
+		iflib_softirq_alloc_generic(ctx, NULL, IFLIB_INTR_TX, NULL, i,
+		    irq_name);
+	}
+
+	return (0);
+}
+
+static void
+mgb_intr_enable_all(if_ctx_t ctx)
+{
+	struct mgb_softc *sc;
+	if_softc_ctx_t scctx;
+	int i, dmac_enable = 0, intr_sts = 0, vec_en = 0;
+
+	sc = iflib_get_softc(ctx);
+	scctx = iflib_get_softc_ctx(ctx);
+	intr_sts |= MGB_INTR_STS_ANY;
+	vec_en |= MGB_INTR_STS_ANY;
+
+	for (i = 0; i < scctx->isc_nrxqsets; i++) {
+		intr_sts |= MGB_INTR_STS_RX(i);
+		dmac_enable |= MGB_DMAC_RX_INTR_ENBL(i);
+		vec_en |= MGB_INTR_RX_VEC_STS(i);
+	}
+
+	/* TX interrupts aren't needed ... */
+
+	CSR_WRITE_REG(sc, MGB_INTR_ENBL_SET, intr_sts);
+	CSR_WRITE_REG(sc, MGB_INTR_VEC_ENBL_SET, vec_en);
+	CSR_WRITE_REG(sc, MGB_DMAC_INTR_STS, dmac_enable);
+	CSR_WRITE_REG(sc, MGB_DMAC_INTR_ENBL_SET, dmac_enable);
+}
+
+static void
+mgb_intr_disable_all(if_ctx_t ctx)
+{
+	struct mgb_softc *sc;
+
+	sc = iflib_get_softc(ctx);
+	CSR_WRITE_REG(sc, MGB_INTR_ENBL_CLR, UINT32_MAX);
+	CSR_WRITE_REG(sc, MGB_INTR_VEC_ENBL_CLR, UINT32_MAX);
+	CSR_WRITE_REG(sc, MGB_INTR_STS, UINT32_MAX);
+
+	CSR_WRITE_REG(sc, MGB_DMAC_INTR_ENBL_CLR, UINT32_MAX);
+	CSR_WRITE_REG(sc, MGB_DMAC_INTR_STS, UINT32_MAX);
+}
+
+static int
+mgb_rx_queue_intr_enable(if_ctx_t ctx, uint16_t qid)
+{
+	/* called after successful rx isr */
+	struct mgb_softc *sc;
+
+	sc = iflib_get_softc(ctx);
+	CSR_WRITE_REG(sc, MGB_INTR_VEC_ENBL_SET, MGB_INTR_RX_VEC_STS(qid));
+	CSR_WRITE_REG(sc, MGB_INTR_ENBL_SET, MGB_INTR_STS_RX(qid));
+
+	CSR_WRITE_REG(sc, MGB_DMAC_INTR_STS, MGB_DMAC_RX_INTR_ENBL(qid));
+	CSR_WRITE_REG(sc, MGB_DMAC_INTR_ENBL_SET, MGB_DMAC_RX_INTR_ENBL(qid));
+	return (0);
+}
+
+static int
+mgb_tx_queue_intr_enable(if_ctx_t ctx, uint16_t qid)
+{
+	/* XXX: not called (since tx interrupts not used) */
+	struct mgb_softc *sc;
+
+	sc = iflib_get_softc(ctx);
+
+	CSR_WRITE_REG(sc, MGB_INTR_ENBL_SET, MGB_INTR_STS_TX(qid));
+
+	CSR_WRITE_REG(sc, MGB_DMAC_INTR_STS, MGB_DMAC_TX_INTR_ENBL(qid));
+	CSR_WRITE_REG(sc, MGB_DMAC_INTR_ENBL_SET, MGB_DMAC_TX_INTR_ENBL(qid));
+	return (0);
+}
+
+static bool
+mgb_intr_test(struct mgb_softc *sc)
+{
+	int i;
+
+	sc->isr_test_flag = false;
+	CSR_WRITE_REG(sc, MGB_INTR_STS, MGB_INTR_STS_TEST);
+	CSR_WRITE_REG(sc, MGB_INTR_VEC_ENBL_SET, MGB_INTR_STS_ANY);
+	CSR_WRITE_REG(sc, MGB_INTR_ENBL_SET,
+	    MGB_INTR_STS_ANY | MGB_INTR_STS_TEST);
+	CSR_WRITE_REG(sc, MGB_INTR_SET, MGB_INTR_STS_TEST);
+	if (sc->isr_test_flag)
+		return true;
+	for (i = 0; i < MGB_TIMEOUT; i++) {
+		DELAY(10);
+		if (sc->isr_test_flag)
+			break;
+	}
+	CSR_WRITE_REG(sc, MGB_INTR_ENBL_CLR, MGB_INTR_STS_TEST);
+	CSR_WRITE_REG(sc, MGB_INTR_STS, MGB_INTR_STS_TEST);
+	return sc->isr_test_flag;
+}
+
+static int
+mgb_isc_txd_encap(void *xsc , if_pkt_info_t ipi)
+{
+	struct mgb_softc *sc;
+	if_softc_ctx_t scctx;
+	struct mgb_ring_data *rdata;
+	struct mgb_ring_desc *txd;
+	bus_dma_segment_t *segs;
+	qidx_t pidx, nsegs;
+	int i;
+
+	KASSERT(ipi->ipi_qsidx == 0,
+	    ("tried to refill TX Channel %d.\n", ipi->ipi_qsidx));
+	sc = xsc;
+	scctx = iflib_get_softc_ctx(sc->ctx);
+	rdata = &sc->tx_ring_data;
+
+	pidx = ipi->ipi_pidx;
+	segs = ipi->ipi_segs;
+	nsegs = ipi->ipi_nsegs;
+
+	/* For each seg, create a descriptor */
+	for (i = 0; i < nsegs; ++i) {
+		KASSERT(nsegs == 1, ("Multisegment packet !!!!!\n"));
+		txd = &rdata->ring[pidx];
+		txd->ctl = htole32(
+		    (segs[i].ds_len & MGB_DESC_CTL_BUFLEN_MASK ) |
+		    /*
+		     * XXX: This will be wrong in the multipacket case
+		     * I suspect FS should be for the first packet and
+		     * LS should be for the last packet
+		     */
+		    MGB_TX_DESC_CTL_FS | MGB_TX_DESC_CTL_LS |
+		    MGB_DESC_CTL_FCS);
+		txd->addr.low = htole32(CSR_TRANSLATE_ADDR_LOW32(
+		    segs[i].ds_addr));
+		txd->addr.high = htole32(CSR_TRANSLATE_ADDR_HIGH32(
+		    segs[i].ds_addr));
+		txd->sts = htole32(
+		    (segs[i].ds_len << 16) & MGB_DESC_FRAME_LEN_MASK);
+		pidx = MGB_NEXT_RING_IDX(pidx);
+	}
+	ipi->ipi_new_pidx = pidx;
+	return (0);
+}
+
+static void
+mgb_isc_txd_flush(void *xsc, uint16_t txqid, qidx_t pidx)
+{
+	struct mgb_softc *sc;
+	struct mgb_ring_data *rdata;
+
+	KASSERT(txqid == 0, ("tried to flush TX Channel %d.\n", txqid));
+	sc = xsc;
+	rdata = &sc->tx_ring_data;
+
+	if (rdata->last_tail != pidx) {
+		rdata->last_tail = pidx;
+		CSR_WRITE_REG(sc, MGB_DMA_TX_TAIL(txqid), rdata->last_tail);
+	}
+}
+
+static int
+mgb_isc_txd_credits_update(void *xsc, uint16_t txqid, bool clear)
+{
+	struct mgb_softc *sc;
+	struct mgb_ring_desc *txd;
+	struct mgb_ring_data *rdata;
+	int processed = 0;
+
+	/*
+	 * > If clear is true, we need to report the number of TX command ring
+	 * > descriptors that have been processed by the device.  If clear is
+	 * > false, we just need to report whether or not at least one TX
+	 * > command ring descriptor has been processed by the device.
+	 * - vmx driver
+	 */
+	KASSERT(txqid == 0, ("tried to credits_update TX Channel %d.\n",
+	    txqid));
+	sc = xsc;
+	rdata = &sc->tx_ring_data;
+
+	while (*(rdata->head_wb) != rdata->last_head) {
+		if (!clear)
+			return 1;
+
+		txd = &rdata->ring[rdata->last_head];
+		memset(txd, 0, sizeof(struct mgb_ring_desc));
+		rdata->last_head = MGB_NEXT_RING_IDX(rdata->last_head);
+		processed++;
+	}
+
+	return (processed);
+}
+
+static int
+mgb_isc_rxd_available(void *xsc, uint16_t rxqid, qidx_t idx, qidx_t budget)
+{
+	struct mgb_softc *sc;
+	if_softc_ctx_t scctx;
+	struct mgb_ring_data *rdata;
+	int avail = 0;
+
+	sc = xsc;
+	KASSERT(rxqid == 0, ("tried to check availability in RX Channel %d.\n",
+	    rxqid));
+
+	rdata = &sc->rx_ring_data;
+	scctx = iflib_get_softc_ctx(sc->ctx);
+	for (; idx != *(rdata->head_wb);
+	    idx = MGB_NEXT_RING_IDX(idx)) {
+		avail++;
+		/* XXX: Could verify desc is device owned here */
+		if (avail == budget)
+			break;
+	}
+	return (avail);
+}
+
+static int
+mgb_isc_rxd_pkt_get(void *xsc, if_rxd_info_t ri)
+{
+	struct mgb_softc *sc;
+	struct mgb_ring_data *rdata;
+	struct mgb_ring_desc rxd;
+	int total_len;
+
+	KASSERT(ri->iri_qsidx == 0,
+	    ("tried to check availability in RX Channel %d\n", ri->iri_qsidx));
+	sc = xsc;
+	total_len = 0;
+	rdata = &sc->rx_ring_data;
+
+	while (*(rdata->head_wb) != rdata->last_head) {
+		/* copy ring desc and do swapping */
+		rxd = rdata->ring[rdata->last_head];
+		rxd.ctl = le32toh(rxd.ctl);
+		rxd.addr.low = le32toh(rxd.ctl);
+		rxd.addr.high = le32toh(rxd.ctl);
+		rxd.sts = le32toh(rxd.ctl);
+
+		if ((rxd.ctl & MGB_DESC_CTL_OWN) != 0) {
+			device_printf(sc->dev,
+			    "Tried to read descriptor ... "
+			    "found that it's owned by the driver\n");
+			return EINVAL;
+		}
+		if ((rxd.ctl & MGB_RX_DESC_CTL_FS) == 0) {
+			device_printf(sc->dev,
+			    "Tried to read descriptor ... "
+			    "found that FS is not set.\n");
+			device_printf(sc->dev, "Tried to read descriptor ... that it FS is not set.\n");
+			return EINVAL;
+		}
+		/* XXX: Multi-packet support */
+		if ((rxd.ctl & MGB_RX_DESC_CTL_LS) == 0) {
+			device_printf(sc->dev,
+			    "Tried to read descriptor ... "
+			    "found that LS is not set. (Multi-buffer packets not yet supported)\n");
+			return EINVAL;
+		}
+		ri->iri_frags[0].irf_flid = 0;
+		ri->iri_frags[0].irf_idx = rdata->last_head;
+		ri->iri_frags[0].irf_len = MGB_DESC_GET_FRAME_LEN(&rxd);
+		total_len += ri->iri_frags[0].irf_len;
+
+		rdata->last_head = MGB_NEXT_RING_IDX(rdata->last_head);
+		break;
+	}
+	ri->iri_nfrags = 1;
+	ri->iri_len = total_len;
+
+	return (0);
+}
+
+static void
+mgb_isc_rxd_refill(void *xsc, if_rxd_update_t iru)
+{
+	if_softc_ctx_t scctx;
+	struct mgb_softc *sc;
+	struct mgb_ring_data *rdata;
+	struct mgb_ring_desc *rxd;
+	uint64_t *paddrs;
+	qidx_t *idxs;
+	qidx_t idx;
+	int count, len;
+
+	count = iru->iru_count;
+	len = iru->iru_buf_size;
+	idxs = iru->iru_idxs;
+	paddrs = iru->iru_paddrs;
+	KASSERT(iru->iru_qsidx == 0,
+	    ("tried to refill RX Channel %d.\n", iru->iru_qsidx));
+
+	sc = xsc;
+	scctx = iflib_get_softc_ctx(sc->ctx);
+	rdata = &sc->rx_ring_data;
+
+	while (count > 0) {
+		idx = idxs[--count];
+		rxd = &rdata->ring[idx];
+
+		rxd->sts = 0;
+		rxd->addr.low =
+		    htole32(CSR_TRANSLATE_ADDR_LOW32(paddrs[count]));
+		rxd->addr.high =
+		    htole32(CSR_TRANSLATE_ADDR_HIGH32(paddrs[count]));
+		rxd->ctl = htole32(MGB_DESC_CTL_OWN |
+		    (len & MGB_DESC_CTL_BUFLEN_MASK));
+	}
+	return;
+}
+
+static void
+mgb_isc_rxd_flush(void *xsc, uint16_t rxqid, uint8_t flid, qidx_t pidx)
+{
+	struct mgb_softc *sc;
+
+	sc = xsc;
+
+	KASSERT(rxqid == 0, ("tried to flush RX Channel %d.\n", rxqid));
+	sc->rx_ring_data.last_tail = pidx;
+	CSR_WRITE_REG(sc, MGB_DMA_RX_TAIL(rxqid), sc->rx_ring_data.last_tail);
+	return;
+}
+
+static int
+mgb_test_bar(struct mgb_softc *sc)
+{
+	uint32_t id_rev, dev_id, rev;
+
+	id_rev = CSR_READ_REG(sc, 0);
+	dev_id = id_rev >> 16;
+	rev = id_rev & 0xFFFF;
+	if (dev_id == MGB_LAN7430_DEVICE_ID ||
+	    dev_id == MGB_LAN7431_DEVICE_ID) {
+		return 0;
+	} else {
+		device_printf(sc->dev, "ID check failed.\n");
+		return ENXIO;
+	}
+}
+
+static int
+mgb_alloc_regs(struct mgb_softc *sc)
+{
+	int rid;
+
+	rid = PCIR_BAR(MGB_BAR);
+	pci_enable_busmaster(sc->dev);
+	sc->regs = bus_alloc_resource_any(sc->dev, SYS_RES_MEMORY,
+	    &rid, RF_ACTIVE);
+	if (sc->regs == NULL)
+		 return ENXIO;
+
+	return (0);
+}
+
+static int
+mgb_release_regs(struct mgb_softc *sc)
+{
+	int error = 0;
+
+	if (sc->regs != NULL)
+		error = bus_release_resource(sc->dev, SYS_RES_MEMORY,
+		    rman_get_rid(sc->regs), sc->regs);
+	sc->regs = NULL;
+	pci_disable_busmaster(sc->dev);
+	return error;
+}
+
+static int
+mgb_dma_init(struct mgb_softc *sc)
+{
+	if_softc_ctx_t scctx;
+	int ch, error = 0;
+
+	scctx = iflib_get_softc_ctx(sc->ctx);
+
+	for (ch = 0; ch < scctx->isc_nrxqsets; ch++)
+		if ((error = mgb_dma_rx_ring_init(sc, ch)))
+			goto fail;
+
+	for (ch = 0; ch < scctx->isc_nrxqsets; ch++)
+		if ((error = mgb_dma_tx_ring_init(sc, ch)))
+			goto fail;
+
+fail:
+	return error;
+}
+
+static int
+mgb_dma_rx_ring_init(struct mgb_softc *sc, int channel)
+{
+	struct mgb_ring_data *rdata;
+	int ring_config, error = 0;
+
+	rdata = &sc->rx_ring_data;
+	mgb_dmac_control(sc, MGB_DMAC_RX_START, 0, DMAC_RESET);
+	KASSERT(MGB_DMAC_STATE_IS_INITIAL(sc, MGB_DMAC_RX_START, channel),
+	    ("Trying to init channels when not in init state\n"));
+
+	/* write ring address */
+	if (rdata->ring_bus_addr == 0) {
+		device_printf(sc->dev, "Invalid ring bus addr.\n");
+		goto fail;
+	}
+
+	CSR_WRITE_REG(sc, MGB_DMA_RX_BASE_H(channel),
+	    CSR_TRANSLATE_ADDR_HIGH32(rdata->ring_bus_addr));
+	CSR_WRITE_REG(sc, MGB_DMA_RX_BASE_L(channel),
+	    CSR_TRANSLATE_ADDR_LOW32(rdata->ring_bus_addr));
+
+	/* write head pointer writeback address */
+	if (rdata->head_wb_bus_addr == 0) {
+		device_printf(sc->dev, "Invalid head wb bus addr.\n");
+		goto fail;
+	}
+	CSR_WRITE_REG(sc, MGB_DMA_RX_HEAD_WB_H(channel),
+	    CSR_TRANSLATE_ADDR_HIGH32(rdata->head_wb_bus_addr));
+	CSR_WRITE_REG(sc, MGB_DMA_RX_HEAD_WB_L(channel),
+	    CSR_TRANSLATE_ADDR_LOW32(rdata->head_wb_bus_addr));
+
+	/* Enable head pointer writeback */
+	CSR_WRITE_REG(sc, MGB_DMA_RX_CONFIG0(channel), MGB_DMA_HEAD_WB_ENBL);
+
+	ring_config = CSR_READ_REG(sc, MGB_DMA_RX_CONFIG1(channel));
+	/*  ring size */
+	ring_config &= ~MGB_DMA_RING_LEN_MASK;
+	ring_config |= (MGB_DMA_RING_SIZE & MGB_DMA_RING_LEN_MASK);
+	/* packet padding  (PAD_2 is better for IP header alignment ...) */
+	ring_config &= ~MGB_DMA_RING_PAD_MASK;
+	ring_config |= (MGB_DMA_RING_PAD_0 & MGB_DMA_RING_PAD_MASK);
+
+	CSR_WRITE_REG(sc, MGB_DMA_RX_CONFIG1(channel), ring_config);
+
+	rdata->last_head = CSR_READ_REG(sc, MGB_DMA_RX_HEAD(channel));
+
+	mgb_fct_control(sc, MGB_FCT_RX_CTL, channel, FCT_RESET);
+	if (error != 0) {
+		device_printf(sc->dev, "Failed to reset RX FCT.\n");
+		goto fail;
+	}
+	mgb_fct_control(sc, MGB_FCT_RX_CTL, channel, FCT_ENABLE);
+	if (error != 0) {
+		device_printf(sc->dev, "Failed to enable RX FCT.\n");
+		goto fail;
+	}
+	mgb_dmac_control(sc, MGB_DMAC_RX_START, channel, DMAC_START);
+	if (error != 0)
+		device_printf(sc->dev, "Failed to start RX DMAC.\n");
+fail:
+	return (error);
+}
+
+static int
+mgb_dma_tx_ring_init(struct mgb_softc *sc, int channel)
+{
+	struct mgb_ring_data *rdata;
+	int ring_config, error = 0;
+
+	rdata = &sc->tx_ring_data;
+	if ((error = mgb_fct_control(sc, MGB_FCT_TX_CTL, channel, FCT_RESET))) {
+		device_printf(sc->dev, "Failed to reset TX FCT.\n");
+		goto fail;
+	}
+	if ((error = mgb_fct_control(sc, MGB_FCT_TX_CTL, channel,
+	    FCT_ENABLE))) {
+		device_printf(sc->dev, "Failed to enable TX FCT.\n");
+		goto fail;
+	}
+	if ((error = mgb_dmac_control(sc, MGB_DMAC_TX_START, channel,
+	    DMAC_RESET))) {
+		device_printf(sc->dev, "Failed to reset TX DMAC.\n");
+		goto fail;
+	}
+	KASSERT(MGB_DMAC_STATE_IS_INITIAL(sc, MGB_DMAC_TX_START, channel),
+	    ("Trying to init channels in not init state\n"));
+
+	/* write ring address */
+	if (rdata->ring_bus_addr == 0) {
+		device_printf(sc->dev, "Invalid ring bus addr.\n");
+		goto fail;
+	}
+	CSR_WRITE_REG(sc, MGB_DMA_TX_BASE_H(channel),
+	    CSR_TRANSLATE_ADDR_HIGH32(rdata->ring_bus_addr));
+	CSR_WRITE_REG(sc, MGB_DMA_TX_BASE_L(channel),
+	    CSR_TRANSLATE_ADDR_LOW32(rdata->ring_bus_addr));
+
+	/* write ring size */
+	ring_config = CSR_READ_REG(sc, MGB_DMA_TX_CONFIG1(channel));
+	ring_config &= ~MGB_DMA_RING_LEN_MASK;
+	ring_config |= (MGB_DMA_RING_SIZE & MGB_DMA_RING_LEN_MASK);
+	CSR_WRITE_REG(sc, MGB_DMA_TX_CONFIG1(channel), ring_config);
+
+	/* Enable interrupt on completion and head pointer writeback */
+	ring_config = (MGB_DMA_HEAD_WB_LS_ENBL | MGB_DMA_HEAD_WB_ENBL);
+	CSR_WRITE_REG(sc, MGB_DMA_TX_CONFIG0(channel), ring_config);
+
+	/* write head pointer writeback address */
+	if (rdata->head_wb_bus_addr == 0) {
+		device_printf(sc->dev, "Invalid head wb bus addr.\n");
+		goto fail;
+	}
+	CSR_WRITE_REG(sc, MGB_DMA_TX_HEAD_WB_H(channel),
+	    CSR_TRANSLATE_ADDR_HIGH32(rdata->head_wb_bus_addr));
+	CSR_WRITE_REG(sc, MGB_DMA_TX_HEAD_WB_L(channel),
+	    CSR_TRANSLATE_ADDR_LOW32(rdata->head_wb_bus_addr));
+
+	rdata->last_head = CSR_READ_REG(sc, MGB_DMA_TX_HEAD(channel));
+	KASSERT(rdata->last_head == 0, ("MGB_DMA_TX_HEAD was not reset.\n"));
+	rdata->last_tail = 0;
+	CSR_WRITE_REG(sc, MGB_DMA_TX_TAIL(channel), rdata->last_tail);
+
+	if ((error = mgb_dmac_control(sc, MGB_DMAC_TX_START, channel,
+	    DMAC_START)))
+		device_printf(sc->dev, "Failed to start TX DMAC.\n");
+fail:
+	return error;
+}
+
+static int
+mgb_dmac_control(struct mgb_softc *sc, int start, int channel,
+    enum mgb_dmac_cmd cmd)
+{
+	int error = 0;
+
+	switch (cmd) {
+	case DMAC_RESET:
+		CSR_WRITE_REG(sc, MGB_DMAC_CMD,
+		    MGB_DMAC_CMD_RESET(start, channel));
+		error = mgb_wait_for_bits(sc, MGB_DMAC_CMD, 0,
+		    MGB_DMAC_CMD_RESET(start, channel));
+		break;
+
+	case DMAC_START:
+		/*
+		 * NOTE: this simplifies the logic, since it will never
+		 * try to start in STOP_PENDING, but it also increases work.
+		 */
+		error = mgb_dmac_control(sc, start, channel, DMAC_STOP);
+		if (error != 0)
+			return error;
+		CSR_WRITE_REG(sc, MGB_DMAC_CMD,
+		    MGB_DMAC_CMD_START(start, channel));
+		break;
+
+	case DMAC_STOP:
+		CSR_WRITE_REG(sc, MGB_DMAC_CMD,
+		    MGB_DMAC_CMD_STOP(start, channel));
+		error = mgb_wait_for_bits(sc, MGB_DMAC_CMD,
+		    MGB_DMAC_CMD_STOP(start, channel),
+		    MGB_DMAC_CMD_START(start, channel));
+		break;
+	}
+	return error;
+}
+
+static int
+mgb_fct_control(struct mgb_softc *sc, int reg, int channel,
+    enum mgb_fct_cmd cmd)
+{
+
+	switch (cmd) {
+	case FCT_RESET:
+		CSR_WRITE_REG(sc, reg, MGB_FCT_RESET(channel));
+		return mgb_wait_for_bits(sc, reg, 0, MGB_FCT_RESET(channel));
+	case FCT_ENABLE:
+		CSR_WRITE_REG(sc, reg, MGB_FCT_ENBL(channel));
+		return (0);
+	case FCT_DISABLE:
+		CSR_WRITE_REG(sc, reg, MGB_FCT_DSBL(channel));
+		return mgb_wait_for_bits(sc, reg, 0, MGB_FCT_ENBL(channel));
+	}
+}
+
+static int
+mgb_hw_teardown(struct mgb_softc *sc)
+{
+	int err = 0;
+
+	/* Stop MAC */
+	CSR_CLEAR_REG(sc, MGB_MAC_RX, MGB_MAC_ENBL);
+	CSR_WRITE_REG(sc, MGB_MAC_TX, MGB_MAC_ENBL);
+	if ((err = mgb_wait_for_bits(sc, MGB_MAC_RX, MGB_MAC_DSBL, 0)))
+		return (err);
+	if ((err = mgb_wait_for_bits(sc, MGB_MAC_TX, MGB_MAC_DSBL, 0)))
+		return (err);
+	return (err);
+}
+
+static int
+mgb_hw_init(struct mgb_softc *sc)
+{
+	int error = 0;
+
+	error = mgb_hw_reset(sc);
+	if (error != 0)
+		goto fail;
+
+	mgb_mac_init(sc);
+
+	error = mgb_phy_reset(sc);
+	if (error != 0)
+		goto fail;
+
+	error = mgb_dmac_reset(sc);
+	if (error != 0)
+		goto fail;
+
+fail:
+	return error;
+}
+
+static int
+mgb_hw_reset(struct mgb_softc *sc)
+{
+
+	CSR_UPDATE_REG(sc, MGB_HW_CFG, MGB_LITE_RESET);
+	return (mgb_wait_for_bits(sc, MGB_HW_CFG, 0, MGB_LITE_RESET));
+}
+
+static int
+mgb_mac_init(struct mgb_softc *sc)
+{
+
+	/**
+	 * enable automatic duplex detection and
+	 * automatic speed detection
+	 */
+	CSR_UPDATE_REG(sc, MGB_MAC_CR, MGB_MAC_ADD_ENBL | MGB_MAC_ASD_ENBL);
+	CSR_UPDATE_REG(sc, MGB_MAC_TX, MGB_MAC_ENBL);
+	CSR_UPDATE_REG(sc, MGB_MAC_RX, MGB_MAC_ENBL);
+
+	return MGB_STS_OK;
+}
+
+static int
+mgb_phy_reset(struct mgb_softc *sc)
+{
+
+	CSR_UPDATE_BYTE(sc, MGB_PMT_CTL, MGB_PHY_RESET);
+	if (mgb_wait_for_bits(sc, MGB_PMT_CTL, 0, MGB_PHY_RESET) ==
+	    MGB_STS_TIMEOUT)
+		return MGB_STS_TIMEOUT;
+	return (mgb_wait_for_bits(sc, MGB_PMT_CTL, MGB_PHY_READY, 0));
+}
+
+static int
+mgb_dmac_reset(struct mgb_softc *sc)
+{
+
+	CSR_WRITE_REG(sc, MGB_DMAC_CMD, MGB_DMAC_RESET);
+	return (mgb_wait_for_bits(sc, MGB_DMAC_CMD, 0, MGB_DMAC_RESET));
+}
+
+static int
+mgb_wait_for_bits(struct mgb_softc *sc, int reg, int set_bits, int clear_bits)
+{
+	int i, val;
+
+	i = 0;
+	do {
+		/*
+		 * XXX: Datasheets states delay should be > 5 microseconds
+		 * for device reset.
+		 */
+		DELAY(100);
+		val = CSR_READ_REG(sc, reg);
+		if ((val & set_bits) == set_bits &&
+		    (val & clear_bits) == 0)
+			return MGB_STS_OK;
+	} while (i++ < MGB_TIMEOUT);
+
+	return MGB_STS_TIMEOUT;
+}
+
+static void
+mgb_get_ethaddr(struct mgb_softc *sc, struct ether_addr *dest)
+{
+
+	CSR_READ_REG_BYTES(sc, MGB_MAC_ADDR_BASE_L, &dest->octet[0], 4);
+	CSR_READ_REG_BYTES(sc, MGB_MAC_ADDR_BASE_H, &dest->octet[4], 2);
+}
+
+static int
+mgb_miibus_readreg(device_t dev, int phy, int reg)
+{
+	struct mgb_softc *sc;
+	int mii_access;
+
+	sc = iflib_get_softc(device_get_softc(dev));
+
+	if (mgb_wait_for_bits(sc, MGB_MII_ACCESS, 0, MGB_MII_BUSY) ==
+	    MGB_STS_TIMEOUT)
+		return EIO;
+	mii_access = (phy & MGB_MII_PHY_ADDR_MASK) << MGB_MII_PHY_ADDR_SHIFT;
+	mii_access |= (reg & MGB_MII_REG_ADDR_MASK) << MGB_MII_REG_ADDR_SHIFT;
+	mii_access |= MGB_MII_BUSY | MGB_MII_READ;
+	CSR_WRITE_REG(sc, MGB_MII_ACCESS, mii_access);
+	if (mgb_wait_for_bits(sc, MGB_MII_ACCESS, 0, MGB_MII_BUSY) ==
+	    MGB_STS_TIMEOUT)
+		return EIO;
+	return (CSR_READ_2_BYTES(sc, MGB_MII_DATA));
+}
+
+static int
+mgb_miibus_writereg(device_t dev, int phy, int reg, int data)
+{
+	struct mgb_softc *sc;
+	int mii_access;
+
+	sc = iflib_get_softc(device_get_softc(dev));
+
+	if (mgb_wait_for_bits(sc, MGB_MII_ACCESS,
+	    0, MGB_MII_BUSY) == MGB_STS_TIMEOUT)
+		return EIO;
+	mii_access = (phy & MGB_MII_PHY_ADDR_MASK) << MGB_MII_PHY_ADDR_SHIFT;
+	mii_access |= (reg & MGB_MII_REG_ADDR_MASK) << MGB_MII_REG_ADDR_SHIFT;
+	mii_access |= MGB_MII_BUSY | MGB_MII_WRITE;
+	CSR_WRITE_REG(sc, MGB_MII_DATA, data);
+	CSR_WRITE_REG(sc, MGB_MII_ACCESS, mii_access);
+	if (mgb_wait_for_bits(sc, MGB_MII_ACCESS, 0, MGB_MII_BUSY) ==
+	    MGB_STS_TIMEOUT)
+		return EIO;
+	return 0;
+}
+
+/* XXX: May need to lock these up */
+static void
+mgb_miibus_statchg(device_t dev)
+{
+	struct mgb_softc *sc;
+	struct mii_data *miid;
+
+	sc = iflib_get_softc(device_get_softc(dev));
+	miid = device_get_softc(sc->miibus);
+	/* Update baudrate in iflib */
+	sc->baudrate = ifmedia_baudrate(miid->mii_media_active);
+	iflib_link_state_change(sc->ctx, sc->link_state, sc->baudrate);
+}
+
+static void
+mgb_miibus_linkchg(device_t dev)
+{
+	struct mgb_softc *sc;
+	struct mii_data *miid;
+	int link_state;
+
+	sc = iflib_get_softc(device_get_softc(dev));
+	miid = device_get_softc(sc->miibus);
+	/* XXX: copied from miibus_linkchg **/
+	if (miid->mii_media_status & IFM_AVALID) {
+		if (miid->mii_media_status & IFM_ACTIVE)
+			link_state = LINK_STATE_UP;
+		else
+			link_state = LINK_STATE_DOWN;
+	} else
+		link_state = LINK_STATE_UNKNOWN;
+	sc->link_state = link_state;
+	iflib_link_state_change(sc->ctx, sc->link_state, sc->baudrate);
+}
diff --git a/sys/dev/mgb/if_mgb.h b/sys/dev/mgb/if_mgb.h
new file mode 100644
index 000000000000..3257ca9b9127
--- /dev/null
+++ b/sys/dev/mgb/if_mgb.h
@@ -0,0 +1,332 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 The FreeBSD Foundation, Inc.
+ *
+ * This driver was written by Gerald ND Aryeetey <gndaryee@uwaterloo.ca>
+ * under sponsorship from the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+#ifndef _IF_MGB_H_
+#define _IF_MGB_H_
+
+#define MGB_MICROCHIP_VENDOR_ID		0x1055
+#define MGB_LAN7430_DEVICE_ID		0x7430
+#define MGB_LAN7431_DEVICE_ID		0x7431
+
+#define MGB_TIMEOUT			(500)
+
+/** Control/Status Registers **/
+#define MGB_BAR				0 /* PCI Base Address */
+
+/** Reset **/
+#define MGB_HW_CFG			0x10 /** H/W Configuration Register **/
+#define MGB_LITE_RESET 			0x2
+
+/** MAC **/
+#define MGB_MAC_CR			0x0100 /** MAC Crontrol Register **/
+#define MGB_MAC_ADD_ENBL		0x1000 /* Automatic Duplex Detection */
+#define MGB_MAC_ASD_ENBL		0x0800 /* Automatic Speed Detection */
+
+#define MGB_MAC_ADDR_BASE_L		0x11C /** MAC address lower 4 bytes (read) register **/
+#define MGB_MAC_ADDR_BASE_H		0x118 /** MAC address upper 2 bytes (read) register **/
+
+#define MGB_MAC_TX			0x0104
+#define MGB_MAC_RX			0x0108
+#define MGB_MAC_ENBL			(1 << 0)
+#define MGB_MAC_DSBL			(1 << 1)
+
+/** MAC Statistics **/
+#define MGB_MAC_STAT_RX_FCS_ERR_CNT	0x1200
+#define MGB_MAC_STAT_RX_ALIGN_ERR_CNT	0x1204
+#define MGB_MAC_STAT_RX_FRAG_ERR_CNT	0x1208
+#define MGB_MAC_STAT_RX_JABBER_ERR_CNT	0x120C
+#define MGB_MAC_STAT_RX_UNDER_ERR_CNT	0x1210
+#define MGB_MAC_STAT_RX_OVER_ERR_CNT	0x1214
+#define MGB_MAC_STAT_RX_DROPPED_CNT	0x1218
+#define MGB_MAC_STAT_RX_BROADCAST_CNT1	0x1220
+#define MGB_MAC_STAT_RX_BROADCAST_CNT	0x122C
+#define MGB_MAC_STAT_RX_FRAME_CNT	0x1254
+#define MGB_MAC_STAT_RX_DROPPED_CNT	0x1218
+#define MGB_MAC_STAT_RX_BROADCAST_CNT1	0x1220
+#define MGB_MAC_STAT_RX_BROADCAST_CNT	0x122C
+#define MGB_MAC_STAT_RX_FRAME_CNT	0x1254
+/* etc. */
+
+/** Recieve Filtering Engine **/
+#define MGB_RFE_CTL			0x508
+#define MGB_RFE_ALLOW_BROADCAST		(1 << 10)
+#define MGB_RFE_ALLOW_MULTICAST		(1 << 9)
+#define MGB_RFE_ALLOW_UNICAST		(1 << 8)
+#define MGB_RFE_ALLOW_PERFECT_FILTER	(1 << 1)
+
+/** PHY Reset (via power management control) **/
+#define MGB_PMT_CTL			0x14 /** Power Management Control Register **/
+#define MGB_PHY_RESET			0x10
+#define MGB_PHY_READY			0x80
+
+/** FIFO Controller **/
+#define MGB_FCT_TX_CTL			0xC4
+#define MGB_FCT_RX_CTL			0xAC
+#define MGB_FCT_ENBL(_channel)		(1 << (28 + (_channel)))
+#define MGB_FCT_DSBL(_channel)		(1 << (24 + (_channel)))
+#define MGB_FCT_RESET(_channel)		(1 << (20 + (_channel)))
+
+/** DMA Controller **/
+#define MGB_DMAC_CMD			0xC0C
+#define MGB_DMAC_RESET			(1 << 31)
+#define MGB_DMAC_TX_START		16
+#define MGB_DMAC_RX_START		0
+#define MGB_DMAC_CMD_VAL(s, o, ch)	(1 << ((s) + (o) + (ch)))
+#define MGB_DMAC_CMD_RESET(_s, _ch)	MGB_DMAC_CMD_VAL(_s, 8, _ch)
+#define MGB_DMAC_CMD_START(_s, _ch)	MGB_DMAC_CMD_VAL(_s, 4, _ch)
+#define MGB_DMAC_CMD_STOP( _s, _ch)	MGB_DMAC_CMD_VAL(_s, 0, _ch)
+#define MGB_DMAC_STATE(_start, _stop)	\
+	(((_start) ? 2 : 0) | ((_stop) ? 1 : 0))
+#define MGB_DMAC_STATE_INITIAL		MGB_DMAC_STATE(0, 0)
+#define MGB_DMAC_STATE_STARTED		MGB_DMAC_STATE(1, 0)
+#define MGB_DMAC_STATE_STOP_PENDING	MGB_DMAC_STATE(1, 1)
+#define MGB_DMAC_STATE_STOPPED		MGB_DMAC_STATE(0, 1)
+#define MGB_DMAC_CMD_STATE(sc, _s, _ch)				\
+	(MGB_DMAC_STATE(					\
+	    CSR_READ_REG(sc, MGB_DMAC_CMD) & MGB_DMAC_CMD_START(_s, _ch),	\
+	    CSR_READ_REG(sc, MGB_DMAC_CMD) & MGB_DMAC_CMD_STOP(_s, _ch)))
+#define MGB_DMAC_STATE_IS_INITIAL(sc, _s, _ch)			\
+	(MGB_DMAC_CMD_STATE(sc, _s, _ch) == MGB_DMAC_STATE_INITIAL)
+
+#define MGB_DMAC_INTR_STS		0xC10
+#define MGB_DMAC_INTR_ENBL_SET		0xC14
+#define MGB_DMAC_INTR_ENBL_CLR		0xC18
+#define MGB_DMAC_TX_INTR_ENBL(_ch)	(1 << (_ch))
+#define MGB_DMAC_RX_INTR_ENBL(_ch)	(1 << (16 + (_ch)))
+
+/** DMA Rings **/
+/**
+ * Page size is 256 bytes
+ *
+ * Ring size, however, these could be tunable (for RX & TX)
+ * to be a multiple of 4 (max is 65532)
+ *
+ **/
+/* In linux driver these numbers are 50 and 65 for tx and rx .... */
+#define MGB_DMA_RING_SIZE		16 /* in programming guide, this number is 100 */
+#define MGB_DMA_MAXSEGS			32
+#define MGB_DMA_REG(reg, _channel)	((reg) | ((_channel) << 6))
+#define MGB_DMA_RING_LIST_SIZE		\
+	(sizeof(struct mgb_ring_desc) * MGB_DMA_RING_SIZE)
+#define MGB_DMA_RING_INFO_SIZE		\
+	(sizeof(uint32_t) + MGB_DMA_RING_LIST_SIZE)
+
+#define MGB_DMA_TX_CONFIG0(_channel)	MGB_DMA_REG(0x0D40, _channel)
+#define MGB_DMA_TX_CONFIG1(_channel)	MGB_DMA_REG(0x0D44, _channel)
+#define MGB_DMA_TX_BASE_H(_channel)	MGB_DMA_REG(0x0D48, _channel)
+#define MGB_DMA_TX_BASE_L(_channel)	MGB_DMA_REG(0x0D4C, _channel)
+#define MGB_DMA_TX_HEAD_WB_H(_channel)	MGB_DMA_REG(0x0D50, _channel) /* head Writeback */
+#define MGB_DMA_TX_HEAD_WB_L(_channel)	MGB_DMA_REG(0x0D54, _channel)
+#define MGB_DMA_TX_HEAD(_channel)	MGB_DMA_REG(0x0D58, _channel)
+#define MGB_DMA_TX_TAIL(_channel)	MGB_DMA_REG(0x0D5C, _channel)
+
+#define MGB_DMA_RX_CONFIG0(_channel)	MGB_DMA_REG(0x0C40, _channel)
+#define MGB_DMA_RX_CONFIG1(_channel)	MGB_DMA_REG(0x0C44, _channel)
+#define MGB_DMA_RX_BASE_H(_channel)	MGB_DMA_REG(0x0C48, _channel)
+#define MGB_DMA_RX_BASE_L(_channel)	MGB_DMA_REG(0x0C4C, _channel)
+#define MGB_DMA_RX_HEAD_WB_H(_channel)	MGB_DMA_REG(0x0C50, _channel) /* head Writeback */
+#define MGB_DMA_RX_HEAD_WB_L(_channel)	MGB_DMA_REG(0x0C54, _channel)
+#define MGB_DMA_RX_HEAD(_channel)	MGB_DMA_REG(0x0C58, _channel)
+#define MGB_DMA_RX_TAIL(_channel)	MGB_DMA_REG(0x0C5C, _channel)
+
+#define MGB_DMA_RING_LEN_MASK		0xFFFF
+#define MGB_DMA_IOC_ENBL		0x10000000
+#define MGB_DMA_HEAD_WB_LS_ENBL		0x20000000
+#define MGB_DMA_HEAD_WB_ENBL		(1 << 5)
+#define MGB_DMA_RING_PAD_MASK		0x03000000
+#define MGB_DMA_RING_PAD_0		0x00000000
+#define MGB_DMA_RING_PAD_2		0x02000000
+
+#define MGB_DESC_CTL_OWN		(1 << 15)
+#define MGB_DESC_CTL_FCS		(1 << 17)
+#define MGB_DESC_CTL_IOC		(1 << 26)
+#define MGB_TX_DESC_CTL_LS		(1 << 28)
+#define MGB_TX_DESC_CTL_FS		(1 << 29)
+#define MGB_RX_DESC_CTL_LS		(1 << 30)
+#define MGB_RX_DESC_CTL_FS		(1 << 31)
+#define MGB_DESC_CTL_BUFLEN_MASK	(0x0000FFFF)
+#define MGB_DESC_STS_BUFLEN_MASK	(0x00003FFF)
+#define MGB_DESC_FRAME_LEN_MASK		(0x3FFF0000)
+#define MGB_DESC_GET_FRAME_LEN(_desc)	\
+	(((_desc)->ctl & MGB_DESC_FRAME_LEN_MASK) >> 16)
+
+#define MGB_NEXT_RING_IDX(_idx)		(((_idx) + 1) % MGB_DMA_RING_SIZE)
+#define MGB_RING_SPACE(_sc)		\
+	((((_sc)->tx_ring_data.last_head - (_sc)->tx_ring_data.last_tail - 1) \
+	 + MGB_DMA_RING_SIZE ) % MGB_DMA_RING_SIZE )
+
+/** PHY **/
+#define MGB_MII_ACCESS			0x120
+#define MGB_MII_DATA			0x124
+#define MGB_MII_PHY_ADDR_MASK		0x1F
+#define MGB_MII_PHY_ADDR_SHIFT		11
+#define MGB_MII_REG_ADDR_MASK		0x1F
+#define MGB_MII_REG_ADDR_SHIFT		6
+#define MGB_MII_READ			0x0
+#define MGB_MII_WRITE			0x2
+#define MGB_MII_BUSY			0x1
+
+/** Interrupt registers **/
+#define MGB_INTR_STS			0x780
+#define MGB_INTR_SET			0x784 /* This triggers a particular interrupt */
+#define MGB_INTR_ENBL_SET		0x788
+#define MGB_INTR_STS_ANY		(0x1)
+#define MGB_INTR_STS_RX(_channel)	(1 << (24 + (_channel)))
+#define MGB_INTR_STS_RX_ANY		(0xF << 24)
+#define MGB_INTR_STS_TX(_channel)	(1 << (16 + (_channel)))
+#define MGB_INTR_STS_TX_ANY		(0xF << 16)
+#define MGB_INTR_STS_TEST		(1 << 9)
+#define MGB_INTR_ENBL_CLR		0x78C
+
+#define MGB_INTR_VEC_ENBL_SET		0x794
+#define MGB_INTR_VEC_ENBL_CLR		0x798
+#define MGB_INTR_VEC_ENBL_AUTO_CLR	0x79C
+#define MGB_INTR_VEC_RX_MAP		0x7A0
+#define MGB_INTR_VEC_TX_MAP		0x7A4
+#define MGB_INTR_VEC_OTHER_MAP		0x7A8
+#define MGB_INTR_VEC_MAP(_vsts, _ch)	((_vsts) << ((_ch) << 2))
+#define MGB_INTR_VEC_STS(_v)		(1 << (_v))
+#define MGB_INTR_RX_VEC_STS(_qid)	MGB_INTR_VEC_STS((_qid) + 1)
+
+
+#define MGB_STS_OK			( 0 )
+#define MGB_STS_TIMEOUT 		(-1 )
+
+#define CSR_READ_BYTE(sc, reg)		\
+	bus_read_1((sc)->regs, reg)
+
+#define CSR_WRITE_BYTE(sc, reg, val)	\
+	bus_write_1((sc)->regs, reg, val)
+
+#define CSR_UPDATE_BYTE(sc, reg, val)	\
+	CSR_WRITE_BYTE(sc, reg, CSR_READ_BYTE(sc, reg) | (val))
+
+#define CSR_READ_REG(sc, reg)		\
+	bus_read_4((sc)->regs, reg)
+
+#define CSR_WRITE_REG(sc, reg, val)	\
+	bus_write_4((sc)->regs, reg, val)
+
+#define CSR_CLEAR_REG(sc, reg, bits)	\
+	CSR_WRITE_REG(sc, reg, CSR_READ_REG(sc, reg) & ~(bits))
+
+#define CSR_UPDATE_REG(sc, reg, val)	\
+	CSR_WRITE_REG(sc, reg, CSR_READ_REG(sc, reg) | (val))
+
+#define CSR_READ_2_BYTES(sc, reg)	\
+	bus_read_2((sc)->regs, reg)
+
+#define CSR_READ_REG_BYTES(sc, reg, dest, cnt)	\
+	bus_read_region_1((sc)->regs, reg, dest, cnt)
+
+#define CSR_TRANSLATE_ADDR_LOW32(addr)		((uint64_t) (addr) & 0xFFFFFFFF)
+#define CSR_TRANSLATE_ADDR_HIGH32(addr)		((uint64_t) (addr) >> 32)
+
+struct mgb_irq {
+	struct resource			*res;
+	void				*handler;
+};
+
+enum mgb_dmac_cmd { DMAC_RESET, DMAC_START, DMAC_STOP };
+enum mgb_fct_cmd { FCT_RESET, FCT_ENABLE, FCT_DISABLE };
+
+struct mgb_ring_desc_addr {
+	uint32_t				low;
+	uint32_t				high;
+} __packed;
+
+/* TODO: With descriptor bit information
+ * this could be done without masks etc.
+ * (using bitwise structs like vmx,
+ * would have to separate rx/tx ring desc
+ * definitions)
+ */
+struct mgb_ring_desc {
+	uint32_t				ctl; /* data0 */
+	struct mgb_ring_desc_addr		addr; /* data(1|2) */
+	uint32_t				sts; /* data3 */
+} __packed;
+
+#if 0
+struct mgb_ring_info {
+	uint32_t				head_wb;
+	struct mgb_ring_desc			*ring;
+}
+#endif
+#define MGB_HEAD_WB_PTR(_ring_info_ptr)		\
+	((uint32_t *)(_ring_info_ptr))
+
+#define MGB_RING_PTR(_ring_info_ptr)		\
+	((struct mgb_ring_desc *)(MGB_HEAD_WB_PTR(_ring_info_ptr) + 1))
+
+struct mgb_ring_data {
+	uint32_t			*head_wb;
+	struct mgb_ring_desc		*ring;
+
+	bus_addr_t			 head_wb_bus_addr;
+	bus_addr_t			 ring_bus_addr;
+
+	uint32_t			 last_head;
+	uint32_t			 last_tail;
+};
+
+struct mgb_softc {
+	if_ctx_t			 ctx;
+	device_t			 dev;
+
+	struct resource			*regs;
+
+	struct resource			*pba;
+	struct if_irq			 admin_irq;
+	struct if_irq			 rx_irq;
+
+	bool 				 isr_test_flag;
+
+	device_t			 miibus;
+	int				 link_state;
+	int				 baudrate;
+
+	int				 if_flags;
+	int				 ethaddr;
+	int				 flags;
+
+	struct mtx			 mtx;
+	struct callout			 watchdog;
+	int				 timer;
+
+
+	bus_dma_tag_t			 dma_parent_tag;
+	struct mgb_ring_data		 rx_ring_data;
+	struct mgb_ring_data		 tx_ring_data;
+
+};
+
+#endif /* _IF_MGB_H_ */
diff --git a/sys/modules/mgb/Makefile b/sys/modules/mgb/Makefile
new file mode 100644
index 000000000000..3b819239ef0e
--- /dev/null
+++ b/sys/modules/mgb/Makefile
@@ -0,0 +1,14 @@
+# $FreeBSD$
+
+.PATH:	${SRCTOP}/sys/dev/mgb
+
+KMOD	= if_mgb
+SRCS	= if_mgb.c
+SRCS	+= device_if.h bus_if.h pci_if.h
+SRCS	+= ifdi_if.h
+SRCS	+= miibus_if.h
+
+#CFLAGS+= -DIFLIB
+
+.include <bsd.kmod.mk>
+