/* * This file is provided under a CDDLv1 license. When using or * redistributing this file, you may do so under this license. * In redistributing this file this license must be included * and no other modification of this header file is permitted. * * CDDL LICENSE SUMMARY * * Copyright(c) 1999 - 2007 Intel Corporation. All rights reserved. * * The contents of this file are subject to the terms of Version * 1.0 of the Common Development and Distribution License (the "License"). * * You should have received a copy of the License with this software. * You can obtain a copy of the License at * http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. */ /* * Copyright 2007 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms of the CDDLv1. */ #pragma ident "%Z%%M% %I% %E% SMI" /* * ********************************************************************** * * * Module Name: * * e1000g_rx.c * * * * Abstract: * * This file contains some routines that take care of Receive * * interrupt and also for the received packets it sends up to * * upper layer. * * It tries to do a zero copy if free buffers are available in * * the pool. * * * * ********************************************************************** */ #include "e1000g_sw.h" #include "e1000g_debug.h" static p_rx_sw_packet_t e1000g_get_buf(e1000g_rx_ring_t *rx_ring); #pragma inline(e1000g_get_buf) static void e1000g_priv_devi_list_clean(); /* * e1000g_rxfree_func - the call-back function to reclaim rx buffer * * This function is called when an mp is freed by the user thru * freeb call (Only for mp constructed through desballoc call) * It returns back the freed buffer to the freelist */ void e1000g_rxfree_func(p_rx_sw_packet_t packet) { struct e1000g *Adapter; e1000g_rx_ring_t *rx_ring; rx_ring = (e1000g_rx_ring_t *)packet->rx_ring; Adapter = rx_ring->adapter; /* * Here the rx recycling processes different rx packets in different * threads, so we protect it with RW_READER to ensure it won't block * other rx recycling threads. */ rw_enter(&e1000g_rx_detach_lock, RW_READER); if (packet->flag == E1000G_RX_SW_FREE) { rw_exit(&e1000g_rx_detach_lock); return; } if (packet->flag == E1000G_RX_SW_STOP) { packet->flag = E1000G_RX_SW_FREE; rw_exit(&e1000g_rx_detach_lock); rw_enter(&e1000g_rx_detach_lock, RW_WRITER); rx_ring->pending_count--; e1000g_mblks_pending--; if (rx_ring->pending_count == 0) { while (rx_ring->pending_list != NULL) { packet = rx_ring->pending_list; rx_ring->pending_list = rx_ring->pending_list->next; ASSERT(packet->mp == NULL); e1000g_free_rx_sw_packet(packet); } } /* * If e1000g_force_detach is enabled, we need to clean up * the idle priv_dip entries in the private dip list while * e1000g_mblks_pending is zero. */ if (e1000g_force_detach && (e1000g_mblks_pending == 0)) e1000g_priv_devi_list_clean(); rw_exit(&e1000g_rx_detach_lock); return; } if (packet->flag == E1000G_RX_SW_DETACH) { packet->flag = E1000G_RX_SW_FREE; rw_exit(&e1000g_rx_detach_lock); ASSERT(packet->mp == NULL); e1000g_free_rx_sw_packet(packet); /* * Here the e1000g_mblks_pending may be modified by different * rx recycling threads simultaneously, so we need to protect * it with RW_WRITER. */ rw_enter(&e1000g_rx_detach_lock, RW_WRITER); e1000g_mblks_pending--; /* * If e1000g_force_detach is enabled, we need to clean up * the idle priv_dip entries in the private dip list while * e1000g_mblks_pending is zero. */ if (e1000g_force_detach && (e1000g_mblks_pending == 0)) e1000g_priv_devi_list_clean(); rw_exit(&e1000g_rx_detach_lock); return; } packet->flag = E1000G_RX_SW_FREE; if (packet->mp == NULL) { /* * Allocate a mblk that binds to the data buffer */ packet->mp = desballoc((unsigned char *) packet->rx_buf->address - E1000G_IPALIGNROOM, packet->rx_buf->size + E1000G_IPALIGNROOM, BPRI_MED, &packet->free_rtn); if (packet->mp != NULL) { packet->mp->b_rptr += E1000G_IPALIGNROOM; packet->mp->b_wptr += E1000G_IPALIGNROOM; } else { E1000G_STAT(rx_ring->stat_esballoc_fail); } } mutex_enter(&rx_ring->freelist_lock); QUEUE_PUSH_TAIL(&rx_ring->free_list, &packet->Link); rx_ring->avail_freepkt++; mutex_exit(&rx_ring->freelist_lock); rw_exit(&e1000g_rx_detach_lock); } /* * e1000g_priv_devi_list_clean - clean up e1000g_private_devi_list * * We will walk the e1000g_private_devi_list to free the entry marked * with the E1000G_PRIV_DEVI_DETACH flag. */ static void e1000g_priv_devi_list_clean() { private_devi_list_t *devi_node, *devi_del; if (e1000g_private_devi_list == NULL) return; devi_node = e1000g_private_devi_list; while ((devi_node != NULL) && (devi_node->flag == E1000G_PRIV_DEVI_DETACH)) { e1000g_private_devi_list = devi_node->next; kmem_free(devi_node->priv_dip, sizeof (struct dev_info)); kmem_free(devi_node, sizeof (private_devi_list_t)); devi_node = e1000g_private_devi_list; } if (e1000g_private_devi_list == NULL) return; while (devi_node->next != NULL) { if (devi_node->next->flag == E1000G_PRIV_DEVI_DETACH) { devi_del = devi_node->next; devi_node->next = devi_del->next; kmem_free(devi_del->priv_dip, sizeof (struct dev_info)); kmem_free(devi_del, sizeof (private_devi_list_t)); } else { devi_node = devi_node->next; } } } /* * e1000g_rx_setup - setup rx data structures * * This routine initializes all of the receive related * structures. This includes the receive descriptors, the * actual receive buffers, and the rx_sw_packet software * structures. */ void e1000g_rx_setup(struct e1000g *Adapter) { struct e1000_hw *hw; p_rx_sw_packet_t packet; struct e1000_rx_desc *descriptor; uint32_t buf_low; uint32_t buf_high; uint32_t reg_val; int i; int size; e1000g_rx_ring_t *rx_ring; hw = &Adapter->shared; rx_ring = Adapter->rx_ring; /* * zero out all of the receive buffer descriptor memory * assures any previous data or status is erased */ bzero(rx_ring->rbd_area, sizeof (struct e1000_rx_desc) * Adapter->rx_desc_num); if (!Adapter->rx_buffer_setup) { /* Init the list of "Receive Buffer" */ QUEUE_INIT_LIST(&rx_ring->recv_list); /* Init the list of "Free Receive Buffer" */ QUEUE_INIT_LIST(&rx_ring->free_list); /* * Setup Receive list and the Free list. Note that * the both were allocated in one packet area. */ packet = rx_ring->packet_area; descriptor = rx_ring->rbd_first; for (i = 0; i < Adapter->rx_desc_num; i++, packet = packet->next, descriptor++) { ASSERT(packet != NULL); ASSERT(descriptor != NULL); descriptor->buffer_addr = packet->rx_buf->dma_address; /* Add this rx_sw_packet to the receive list */ QUEUE_PUSH_TAIL(&rx_ring->recv_list, &packet->Link); } for (i = 0; i < Adapter->rx_freelist_num; i++, packet = packet->next) { ASSERT(packet != NULL); /* Add this rx_sw_packet to the free list */ QUEUE_PUSH_TAIL(&rx_ring->free_list, &packet->Link); } rx_ring->avail_freepkt = Adapter->rx_freelist_num; Adapter->rx_buffer_setup = B_TRUE; } else { /* Setup the initial pointer to the first rx descriptor */ packet = (p_rx_sw_packet_t) QUEUE_GET_HEAD(&rx_ring->recv_list); descriptor = rx_ring->rbd_first; for (i = 0; i < Adapter->rx_desc_num; i++) { ASSERT(packet != NULL); ASSERT(descriptor != NULL); descriptor->buffer_addr = packet->rx_buf->dma_address; /* Get next rx_sw_packet */ packet = (p_rx_sw_packet_t) QUEUE_GET_NEXT(&rx_ring->recv_list, &packet->Link); descriptor++; } } /* * Setup our descriptor pointers */ rx_ring->rbd_next = rx_ring->rbd_first; size = Adapter->rx_desc_num * sizeof (struct e1000_rx_desc); E1000_WRITE_REG(hw, E1000_RDLEN, size); size = E1000_READ_REG(hw, E1000_RDLEN); /* To get lower order bits */ buf_low = (uint32_t)rx_ring->rbd_dma_addr; /* To get the higher order bits */ buf_high = (uint32_t)(rx_ring->rbd_dma_addr >> 32); E1000_WRITE_REG(hw, E1000_RDBAH, buf_high); E1000_WRITE_REG(hw, E1000_RDBAL, buf_low); /* * Setup our HW Rx Head & Tail descriptor pointers */ E1000_WRITE_REG(hw, E1000_RDT, (uint32_t)(rx_ring->rbd_last - rx_ring->rbd_first)); E1000_WRITE_REG(hw, E1000_RDH, 0); /* * Setup the Receive Control Register (RCTL), and ENABLE the * receiver. The initial configuration is to: Enable the receiver, * accept broadcasts, discard bad packets (and long packets), * disable VLAN filter checking, set the receive descriptor * minimum threshold size to 1/2, and the receive buffer size to * 2k. */ reg_val = E1000_RCTL_EN | /* Enable Receive Unit */ E1000_RCTL_BAM | /* Accept Broadcast Packets */ E1000_RCTL_LPE | /* Large Packet Enable bit */ (hw->mac.mc_filter_type << E1000_RCTL_MO_SHIFT) | E1000_RCTL_RDMTS_HALF | E1000_RCTL_LBM_NO; /* Loopback Mode = none */ if (Adapter->strip_crc) reg_val |= E1000_RCTL_SECRC; /* Strip Ethernet CRC */ switch (hw->mac.max_frame_size) { case ETHERMAX: reg_val |= E1000_RCTL_SZ_2048; break; case FRAME_SIZE_UPTO_4K: reg_val |= E1000_RCTL_SZ_4096 | E1000_RCTL_BSEX; break; case FRAME_SIZE_UPTO_8K: reg_val |= E1000_RCTL_SZ_8192 | E1000_RCTL_BSEX; break; case FRAME_SIZE_UPTO_9K: case FRAME_SIZE_UPTO_16K: reg_val |= E1000_RCTL_SZ_16384 | E1000_RCTL_BSEX; break; default: reg_val |= E1000_RCTL_SZ_2048; break; } if (e1000_tbi_sbp_enabled_82543(hw)) reg_val |= E1000_RCTL_SBP; /* * Enable early receives on supported devices, only takes effect when * packet size is equal or larger than the specified value (in 8 byte * units), e.g. using jumbo frames when setting to E1000_ERT_2048 */ if ((hw->mac.type == e1000_82573) || (hw->mac.type == e1000_ich9lan)) E1000_WRITE_REG(hw, E1000_ERT, E1000_ERT_2048); E1000_WRITE_REG(hw, E1000_RCTL, reg_val); reg_val = E1000_RXCSUM_TUOFL | /* TCP/UDP checksum offload Enable */ E1000_RXCSUM_IPOFL; /* IP checksum offload Enable */ E1000_WRITE_REG(hw, E1000_RXCSUM, reg_val); } /* * e1000g_get_buf - get an rx sw packet from the free_list */ static p_rx_sw_packet_t e1000g_get_buf(e1000g_rx_ring_t *rx_ring) { struct e1000g *Adapter; p_rx_sw_packet_t packet; Adapter = rx_ring->adapter; mutex_enter(&rx_ring->freelist_lock); packet = (p_rx_sw_packet_t) QUEUE_POP_HEAD(&rx_ring->free_list); if (packet != NULL) rx_ring->avail_freepkt--; mutex_exit(&rx_ring->freelist_lock); return (packet); } /* * e1000g_receive - main receive routine * * This routine will process packets received in an interrupt */ mblk_t * e1000g_receive(struct e1000g *Adapter) { struct e1000_hw *hw; mblk_t *nmp; mblk_t *ret_mp; mblk_t *ret_nmp; struct e1000_rx_desc *current_desc; struct e1000_rx_desc *last_desc; p_rx_sw_packet_t packet; p_rx_sw_packet_t newpkt; USHORT length; uint32_t pkt_count; uint32_t desc_count; boolean_t accept_frame; boolean_t end_of_packet; boolean_t need_copy; e1000g_rx_ring_t *rx_ring; dma_buffer_t *rx_buf; uint16_t cksumflags; ret_mp = NULL; ret_nmp = NULL; pkt_count = 0; desc_count = 0; cksumflags = 0; hw = &Adapter->shared; rx_ring = Adapter->rx_ring; /* Sync the Rx descriptor DMA buffers */ (void) ddi_dma_sync(rx_ring->rbd_dma_handle, 0, 0, DDI_DMA_SYNC_FORKERNEL); if (e1000g_check_dma_handle(rx_ring->rbd_dma_handle) != DDI_FM_OK) { ddi_fm_service_impact(Adapter->dip, DDI_SERVICE_DEGRADED); Adapter->chip_state = E1000G_ERROR; } current_desc = rx_ring->rbd_next; if (!(current_desc->status & E1000_RXD_STAT_DD)) { /* * don't send anything up. just clear the RFD */ E1000G_DEBUG_STAT(rx_ring->stat_none); return (ret_mp); } /* * Loop through the receive descriptors starting at the last known * descriptor owned by the hardware that begins a packet. */ while ((current_desc->status & E1000_RXD_STAT_DD) && (pkt_count < Adapter->rx_limit_onintr)) { desc_count++; /* * Now this can happen in Jumbo frame situation. */ if (current_desc->status & E1000_RXD_STAT_EOP) { /* packet has EOP set */ end_of_packet = B_TRUE; } else { /* * If this received buffer does not have the * End-Of-Packet bit set, the received packet * will consume multiple buffers. We won't send this * packet upstack till we get all the related buffers. */ end_of_packet = B_FALSE; } /* * Get a pointer to the actual receive buffer * The mp->b_rptr is mapped to The CurrentDescriptor * Buffer Address. */ packet = (p_rx_sw_packet_t)QUEUE_GET_HEAD(&rx_ring->recv_list); ASSERT(packet != NULL); rx_buf = packet->rx_buf; length = current_desc->length; #ifdef __sparc if (packet->dma_type == USE_DVMA) dvma_sync(rx_buf->dma_handle, 0, DDI_DMA_SYNC_FORKERNEL); else (void) ddi_dma_sync(rx_buf->dma_handle, E1000G_IPALIGNROOM, length, DDI_DMA_SYNC_FORKERNEL); #else (void) ddi_dma_sync(rx_buf->dma_handle, E1000G_IPALIGNROOM, length, DDI_DMA_SYNC_FORKERNEL); #endif if (e1000g_check_dma_handle( rx_buf->dma_handle) != DDI_FM_OK) { ddi_fm_service_impact(Adapter->dip, DDI_SERVICE_DEGRADED); Adapter->chip_state = E1000G_ERROR; } accept_frame = (current_desc->errors == 0) || ((current_desc->errors & (E1000_RXD_ERR_TCPE | E1000_RXD_ERR_IPE)) != 0); if (hw->mac.type == e1000_82543) { unsigned char last_byte; last_byte = *((unsigned char *)rx_buf->address + length - 1); if (TBI_ACCEPT(hw, current_desc->status, current_desc->errors, current_desc->length, last_byte)) { e1000_tbi_adjust_stats(Adapter, length, hw->mac.addr); length--; accept_frame = B_TRUE; } else if (e1000_tbi_sbp_enabled_82543(hw) && (current_desc->errors == E1000_RXD_ERR_CE)) { accept_frame = B_TRUE; } } /* * Indicate the packet to the NOS if it was good. * Normally, hardware will discard bad packets for us. * Check for the packet to be a valid Ethernet packet */ if (!accept_frame) { /* * error in incoming packet, either the packet is not a * ethernet size packet, or the packet has an error. In * either case, the packet will simply be discarded. */ E1000G_DEBUGLOG_0(Adapter, E1000G_INFO_LEVEL, "Process Receive Interrupts: Error in Packet\n"); E1000G_STAT(rx_ring->stat_error); /* * Returning here as we are done here. There is * no point in waiting for while loop to elapse * and the things which were done. More efficient * and less error prone... */ goto rx_drop; } /* * If the Ethernet CRC is not stripped by the hardware, * we need to strip it before sending it up to the stack. */ if (end_of_packet && !Adapter->strip_crc) { if (length > CRC_LENGTH) { length -= CRC_LENGTH; } else { /* * If the fragment is smaller than the CRC, * drop this fragment, do the processing of * the end of the packet. */ ASSERT(rx_ring->rx_mblk_tail != NULL); rx_ring->rx_mblk_tail->b_wptr -= CRC_LENGTH - length; rx_ring->rx_mblk_len -= CRC_LENGTH - length; QUEUE_POP_HEAD(&rx_ring->recv_list); goto rx_end_of_packet; } } need_copy = B_TRUE; if (length <= Adapter->rx_bcopy_thresh) goto rx_copy; /* * Get the pre-constructed mblk that was associated * to the receive data buffer. */ if (packet->mp == NULL) { packet->mp = desballoc((unsigned char *) rx_buf->address - E1000G_IPALIGNROOM, length + E1000G_IPALIGNROOM, BPRI_MED, &packet->free_rtn); if (packet->mp != NULL) { packet->mp->b_rptr += E1000G_IPALIGNROOM; packet->mp->b_wptr += E1000G_IPALIGNROOM; } else { E1000G_STAT(rx_ring->stat_esballoc_fail); } } if (packet->mp != NULL) { /* * We have two sets of buffer pool. One associated with * the Rxdescriptors and other a freelist buffer pool. * Each time we get a good packet, Try to get a buffer * from the freelist pool using e1000g_get_buf. If we * get free buffer, then replace the descriptor buffer * address with the free buffer we just got, and pass * the pre-constructed mblk upstack. (note no copying) * * If we failed to get a free buffer, then try to * allocate a new buffer(mp) and copy the recv buffer * content to our newly allocated buffer(mp). Don't * disturb the desriptor buffer address. (note copying) */ newpkt = e1000g_get_buf(rx_ring); if (newpkt != NULL) { /* * Get the mblk associated to the data, * and strip it off the sw packet. */ nmp = packet->mp; packet->mp = NULL; packet->flag = E1000G_RX_SW_SENDUP; /* * Now replace old buffer with the new * one we got from free list * Both the RxSwPacket as well as the * Receive Buffer Descriptor will now * point to this new packet. */ packet = newpkt; current_desc->buffer_addr = newpkt->rx_buf->dma_address; need_copy = B_FALSE; } else { E1000G_DEBUG_STAT(rx_ring->stat_no_freepkt); } } rx_copy: if (need_copy) { /* * No buffers available on free list, * bcopy the data from the buffer and * keep the original buffer. Dont want to * do this.. Yack but no other way */ if ((nmp = allocb(length + E1000G_IPALIGNROOM, BPRI_MED)) == NULL) { /* * The system has no buffers available * to send up the incoming packet, hence * the packet will have to be processed * when there're more buffers available. */ E1000G_STAT(rx_ring->stat_allocb_fail); goto rx_drop; } nmp->b_rptr += E1000G_IPALIGNROOM; nmp->b_wptr += E1000G_IPALIGNROOM; /* * The free list did not have any buffers * available, so, the received packet will * have to be copied into a mp and the original * buffer will have to be retained for future * packet reception. */ bcopy(rx_buf->address, nmp->b_wptr, length); } /* * The rx_sw_packet MUST be popped off the * RxSwPacketList before either a putnext or freemsg * is done on the mp that has now been created by the * desballoc. If not, it is possible that the free * routine will get called from the interrupt context * and try to put this packet on the free list */ (p_rx_sw_packet_t)QUEUE_POP_HEAD(&rx_ring->recv_list); ASSERT(nmp != NULL); nmp->b_wptr += length; if (rx_ring->rx_mblk == NULL) { /* * TCP/UDP checksum offload and * IP checksum offload */ if (!(current_desc->status & E1000_RXD_STAT_IXSM)) { /* * Check TCP/UDP checksum */ if ((current_desc->status & E1000_RXD_STAT_TCPCS) && !(current_desc->errors & E1000_RXD_ERR_TCPE)) cksumflags |= HCK_FULLCKSUM | HCK_FULLCKSUM_OK; /* * Check IP Checksum */ if ((current_desc->status & E1000_RXD_STAT_IPCS) && !(current_desc->errors & E1000_RXD_ERR_IPE)) cksumflags |= HCK_IPV4_HDRCKSUM; } } /* * We need to maintain our packet chain in the global * Adapter structure, for the Rx processing can end * with a fragment that has no EOP set. */ if (rx_ring->rx_mblk == NULL) { /* Get the head of the message chain */ rx_ring->rx_mblk = nmp; rx_ring->rx_mblk_tail = nmp; rx_ring->rx_mblk_len = length; } else { /* Not the first packet */ /* Continue adding buffers */ rx_ring->rx_mblk_tail->b_cont = nmp; rx_ring->rx_mblk_tail = nmp; rx_ring->rx_mblk_len += length; } ASSERT(rx_ring->rx_mblk != NULL); ASSERT(rx_ring->rx_mblk_tail != NULL); ASSERT(rx_ring->rx_mblk_tail->b_cont == NULL); /* * Now this MP is ready to travel upwards but some more * fragments are coming. * We will send packet upwards as soon as we get EOP * set on the packet. */ if (!end_of_packet) { /* * continue to get the next descriptor, * Tail would be advanced at the end */ goto rx_next_desc; } rx_end_of_packet: /* * Found packet with EOP * Process the last fragment. */ if (cksumflags != 0) { (void) hcksum_assoc(rx_ring->rx_mblk, NULL, NULL, 0, 0, 0, 0, cksumflags, 0); cksumflags = 0; } /* * Count packets that span multi-descriptors */ E1000G_DEBUG_STAT_COND(rx_ring->stat_multi_desc, (rx_ring->rx_mblk->b_cont != NULL)); /* * Append to list to send upstream */ if (ret_mp == NULL) { ret_mp = ret_nmp = rx_ring->rx_mblk; } else { ret_nmp->b_next = rx_ring->rx_mblk; ret_nmp = rx_ring->rx_mblk; } ret_nmp->b_next = NULL; rx_ring->rx_mblk = NULL; rx_ring->rx_mblk_tail = NULL; rx_ring->rx_mblk_len = 0; pkt_count++; rx_next_desc: /* * Zero out the receive descriptors status */ current_desc->status = 0; if (current_desc == rx_ring->rbd_last) rx_ring->rbd_next = rx_ring->rbd_first; else rx_ring->rbd_next++; last_desc = current_desc; current_desc = rx_ring->rbd_next; /* * Put the buffer that we just indicated back * at the end of our list */ QUEUE_PUSH_TAIL(&rx_ring->recv_list, &packet->Link); } /* while loop */ if (pkt_count >= Adapter->rx_limit_onintr) E1000G_STAT(rx_ring->stat_exceed_pkt); /* Sync the Rx descriptor DMA buffers */ (void) ddi_dma_sync(rx_ring->rbd_dma_handle, 0, 0, DDI_DMA_SYNC_FORDEV); /* * Advance the E1000's Receive Queue #0 "Tail Pointer". */ E1000_WRITE_REG(hw, E1000_RDT, (uint32_t)(last_desc - rx_ring->rbd_first)); if (e1000g_check_acc_handle(Adapter->osdep.reg_handle) != DDI_FM_OK) { ddi_fm_service_impact(Adapter->dip, DDI_SERVICE_DEGRADED); Adapter->chip_state = E1000G_ERROR; } return (ret_mp); rx_drop: /* * Zero out the receive descriptors status */ current_desc->status = 0; /* Sync the Rx descriptor DMA buffers */ (void) ddi_dma_sync(rx_ring->rbd_dma_handle, 0, 0, DDI_DMA_SYNC_FORDEV); if (current_desc == rx_ring->rbd_last) rx_ring->rbd_next = rx_ring->rbd_first; else rx_ring->rbd_next++; last_desc = current_desc; (p_rx_sw_packet_t)QUEUE_POP_HEAD(&rx_ring->recv_list); QUEUE_PUSH_TAIL(&rx_ring->recv_list, &packet->Link); /* * Reclaim all old buffers already allocated during * Jumbo receives.....for incomplete reception */ if (rx_ring->rx_mblk != NULL) { freemsg(rx_ring->rx_mblk); rx_ring->rx_mblk = NULL; rx_ring->rx_mblk_tail = NULL; rx_ring->rx_mblk_len = 0; } /* * Advance the E1000's Receive Queue #0 "Tail Pointer". */ E1000_WRITE_REG(hw, E1000_RDT, (uint32_t)(last_desc - rx_ring->rbd_first)); if (e1000g_check_acc_handle(Adapter->osdep.reg_handle) != DDI_FM_OK) { ddi_fm_service_impact(Adapter->dip, DDI_SERVICE_DEGRADED); Adapter->chip_state = E1000G_ERROR; } return (ret_mp); }