diff mbox

[v3,14/49] IB/hfi1: add low lower receive functions

Message ID 20150617122951.8744.73357.stgit@phlsvslse11.ph.intel.com (mailing list archive)
State Changes Requested
Headers show

Commit Message

Marciniszyn, Mike June 17, 2015, 12:29 p.m. UTC
Signed-off-by: Andrew Friedley <andrew.friedley@intel.com>
Signed-off-by: Arthur Kepner <arthur.kepner@intel.com>
Signed-off-by: Brendan Cunningham <brendan.cunningham@intel.com>
Signed-off-by: Brian Welty <brian.welty@intel.com>
Signed-off-by: Caz Yokoyama <caz.yokoyama@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jim Snow <jim.m.snow@intel.com>
Signed-off-by: John Gregor <john.a.gregor@intel.com>
Signed-off-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Kevin Pine <kevin.pine@intel.com>
Signed-off-by: Kyle Liddell <kyle.liddell@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Ravi Krishnaswamy <ravi.krishnaswamy@intel.com>
Signed-off-by: Sadanand Warrier <sadanand.warrier@intel.com>
Signed-off-by: Sanath Kumar <sanath.s.kumar@intel.com>
Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Vlad Danushevsky <vladimir.danusevsky@intel.com>
---
 drivers/infiniband/hw/hfi1/driver.c | 1061 +++++++++++++++++++++++++++++++++++
 1 file changed, 1061 insertions(+)
 create mode 100644 drivers/infiniband/hw/hfi1/driver.c


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diff mbox

Patch

diff --git a/drivers/infiniband/hw/hfi1/driver.c b/drivers/infiniband/hw/hfi1/driver.c
new file mode 100644
index 0000000..6db7668
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/driver.c
@@ -0,0 +1,1061 @@ 
+/*
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  - Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  - 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.
+ *  - Neither the name of Intel Corporation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
+ * OWNER 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 <linux/spinlock.h>
+#include <linux/pci.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/vmalloc.h>
+#include <linux/module.h>
+#include <linux/prefetch.h>
+
+#include "hfi.h"
+#include "trace.h"
+#include "qp.h"
+#include "sdma.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) DRIVER_NAME ": " fmt
+
+/*
+ * The size has to be longer than this string, so we can append
+ * board/chip information to it in the initialization code.
+ */
+const char ib_hfi1_version[] = HFI1_DRIVER_VERSION "\n";
+
+DEFINE_SPINLOCK(hfi1_devs_lock);
+LIST_HEAD(hfi1_dev_list);
+DEFINE_MUTEX(hfi1_mutex);	/* general driver use */
+
+unsigned int hfi1_max_mtu;
+module_param_named(max_mtu, hfi1_max_mtu, uint, S_IRUGO);
+MODULE_PARM_DESC(max_mtu, "Set max MTU bytes, default is 8192");
+
+unsigned int hfi1_cu = 1;
+module_param_named(cu, hfi1_cu, uint, S_IRUGO);
+MODULE_PARM_DESC(cu, "Credit return units");
+
+unsigned long hfi1_cap_mask = HFI1_CAP_MASK_DEFAULT;
+static int hfi1_caps_set(const char *, const struct kernel_param *);
+static int hfi1_caps_get(char *, const struct kernel_param *);
+static const struct kernel_param_ops cap_ops = {
+	.set = hfi1_caps_set,
+	.get = hfi1_caps_get
+};
+module_param_cb(cap_mask, &cap_ops, &hfi1_cap_mask, S_IWUSR | S_IRUGO);
+MODULE_PARM_DESC(cap_mask, "Bit mask of enabled/disabled HW features");
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("Intel Omni-Path Architecture driver");
+MODULE_VERSION(HFI1_DRIVER_VERSION);
+
+/*
+ * MAX_PKT_RCV is the max # if packets processed per receive interrupt.
+ */
+#define MAX_PKT_RECV 64
+#define EGR_HEAD_UPDATE_THRESHOLD 16
+
+struct hfi1_ib_stats hfi1_stats;
+
+static int hfi1_caps_set(const char *val, const struct kernel_param *kp)
+{
+	int ret = 0;
+	unsigned long *cap_mask_ptr = (unsigned long *)kp->arg,
+		cap_mask = *cap_mask_ptr, value, diff,
+		write_mask = ((HFI1_CAP_WRITABLE_MASK << HFI1_CAP_USER_SHIFT) |
+			      HFI1_CAP_WRITABLE_MASK);
+
+	ret = kstrtoul(val, 0, &value);
+	if (ret) {
+		pr_warn("Invalid module parameter value for 'cap_mask'\n");
+		goto done;
+	}
+	/* Get the changed bits (except the locked bit) */
+	diff = value ^ (cap_mask & ~HFI1_CAP_LOCKED_SMASK);
+
+	/* Remove any bits that are not allowed to change after driver load */
+	if (HFI1_CAP_LOCKED() && (diff & ~write_mask)) {
+		pr_warn("Ignoring non-writable capability bits %#lx\n",
+			diff & ~write_mask);
+		diff &= write_mask;
+	}
+
+	/* Mask off any reserved bits */
+	diff &= ~HFI1_CAP_RESERVED_MASK;
+	/* Clear any previously set and changing bits */
+	cap_mask &= ~diff;
+	/* Update the bits with the new capability */
+	cap_mask |= (value & diff);
+	/* Check for any kernel/user restrictions */
+	diff = (cap_mask & (HFI1_CAP_MUST_HAVE_KERN << HFI1_CAP_USER_SHIFT)) ^
+		((cap_mask & HFI1_CAP_MUST_HAVE_KERN) << HFI1_CAP_USER_SHIFT);
+	cap_mask &= ~diff;
+	/* Set the bitmask to the final set */
+	*cap_mask_ptr = cap_mask;
+done:
+	return ret;
+}
+
+static int hfi1_caps_get(char *buffer, const struct kernel_param *kp)
+{
+	unsigned long cap_mask = *(unsigned long *)kp->arg;
+
+	cap_mask &= ~HFI1_CAP_LOCKED_SMASK;
+	cap_mask |= ((cap_mask & HFI1_CAP_K2U) << HFI1_CAP_USER_SHIFT);
+
+	return scnprintf(buffer, PAGE_SIZE, "0x%lx", cap_mask);
+}
+
+const char *get_unit_name(int unit)
+{
+	static char iname[16];
+
+	snprintf(iname, sizeof(iname), DRIVER_NAME"_%u", unit);
+	return iname;
+}
+
+/*
+ * Return count of units with at least one port ACTIVE.
+ */
+int hfi1_count_active_units(void)
+{
+	struct hfi1_devdata *dd;
+	struct hfi1_pportdata *ppd;
+	unsigned long flags;
+	int pidx, nunits_active = 0;
+
+	spin_lock_irqsave(&hfi1_devs_lock, flags);
+	list_for_each_entry(dd, &hfi1_dev_list, list) {
+		if (!(dd->flags & HFI1_PRESENT) || !dd->kregbase)
+			continue;
+		for (pidx = 0; pidx < dd->num_pports; ++pidx) {
+			ppd = dd->pport + pidx;
+			if (ppd->lid && ppd->linkup) {
+				nunits_active++;
+				break;
+			}
+		}
+	}
+	spin_unlock_irqrestore(&hfi1_devs_lock, flags);
+	return nunits_active;
+}
+
+/*
+ * Return count of all units, optionally return in arguments
+ * the number of usable (present) units, and the number of
+ * ports that are up.
+ */
+int hfi1_count_units(int *npresentp, int *nupp)
+{
+	int nunits = 0, npresent = 0, nup = 0;
+	struct hfi1_devdata *dd;
+	unsigned long flags;
+	int pidx;
+	struct hfi1_pportdata *ppd;
+
+	spin_lock_irqsave(&hfi1_devs_lock, flags);
+
+	list_for_each_entry(dd, &hfi1_dev_list, list) {
+		nunits++;
+		if ((dd->flags & HFI1_PRESENT) && dd->kregbase)
+			npresent++;
+		for (pidx = 0; pidx < dd->num_pports; ++pidx) {
+			ppd = dd->pport + pidx;
+			if (ppd->lid && ppd->linkup)
+				nup++;
+		}
+	}
+
+	spin_unlock_irqrestore(&hfi1_devs_lock, flags);
+
+	if (npresentp)
+		*npresentp = npresent;
+	if (nupp)
+		*nupp = nup;
+
+	return nunits;
+}
+
+/*
+ * Get address of eager buffer from it's index (allocated in chunks, not
+ * contiguous).
+ */
+static inline void *get_egrbuf(const struct hfi1_ctxtdata *rcd, u64 rhf,
+			       u32 *update)
+{
+	u32 idx = rhf_egr_index(rhf), offset = rhf_egr_buf_offset(rhf);
+
+	*update |= !(idx & (rcd->egrbufs.threshold - 1)) && !offset;
+	return (void *)(((u64)(rcd->egrbufs.rcvtids[idx].addr)) +
+			(offset * RCV_BUF_BLOCK_SIZE));
+}
+
+/*
+ * Validate and encode the a given RcvArray Buffer size.
+ * The function will check whether the given size falls within
+ * allowed size ranges for the respective type and, optionally,
+ * return the proper encoding.
+ */
+inline int hfi1_rcvbuf_validate(u32 size, u8 type, u16 *encoded)
+{
+	if (unlikely(!IS_ALIGNED(size, PAGE_SIZE)))
+		return 0;
+	if (unlikely(size < MIN_EAGER_BUFFER))
+		return 0;
+	if (size >
+	    (type == PT_EAGER ? MAX_EAGER_BUFFER : MAX_EXPECTED_BUFFER))
+		return 0;
+	if (encoded)
+		*encoded = ilog2(size / PAGE_SIZE) + 1;
+	return 1;
+}
+
+static void rcv_hdrerr(struct hfi1_ctxtdata *rcd, struct hfi1_pportdata *ppd,
+		       struct hfi1_packet *packet)
+{
+	struct hfi1_message_header *rhdr = packet->hdr;
+	u32 rte = rhf_rcv_type_err(packet->rhf);
+	int lnh = be16_to_cpu(rhdr->lrh[0]) & 3;
+	struct hfi1_ibport *ibp = &ppd->ibport_data;
+
+	if (packet->rhf & (RHF_VCRC_ERR | RHF_ICRC_ERR))
+		return;
+
+	if (packet->rhf & RHF_TID_ERR) {
+		/* For TIDERR and RC QPs preemptively schedule a NAK */
+		struct hfi1_ib_header *hdr = (struct hfi1_ib_header *)rhdr;
+		struct hfi1_other_headers *ohdr = NULL;
+		u32 tlen = rhf_pkt_len(packet->rhf); /* in bytes */
+		u16 lid  = be16_to_cpu(hdr->lrh[1]);
+		u32 qp_num;
+		u32 rcv_flags = 0;
+
+		/* Sanity check packet */
+		if (tlen < 24)
+			goto drop;
+
+		/* Check for GRH */
+		if (lnh == HFI1_LRH_BTH)
+			ohdr = &hdr->u.oth;
+		else if (lnh == HFI1_LRH_GRH) {
+			u32 vtf;
+
+			ohdr = &hdr->u.l.oth;
+			if (hdr->u.l.grh.next_hdr != IB_GRH_NEXT_HDR)
+				goto drop;
+			vtf = be32_to_cpu(hdr->u.l.grh.version_tclass_flow);
+			if ((vtf >> IB_GRH_VERSION_SHIFT) != IB_GRH_VERSION)
+				goto drop;
+			rcv_flags |= HFI1_HAS_GRH;
+		} else
+			goto drop;
+
+		/* Get the destination QP number. */
+		qp_num = be32_to_cpu(ohdr->bth[1]) & HFI1_QPN_MASK;
+		if (lid < HFI1_MULTICAST_LID_BASE) {
+			struct hfi1_qp *qp;
+
+			qp = hfi1_lookup_qpn(ibp, qp_num);
+			if (!qp)
+				goto drop;
+
+			/*
+			 * Handle only RC QPs - for other QP types drop error
+			 * packet.
+			 */
+			spin_lock(&qp->r_lock);
+
+			/* Check for valid receive state. */
+			if (!(ib_hfi1_state_ops[qp->state] &
+			      HFI1_PROCESS_RECV_OK)) {
+				ibp->n_pkt_drops++;
+			}
+
+			switch (qp->ibqp.qp_type) {
+			case IB_QPT_RC:
+				hfi1_rc_hdrerr(
+					rcd,
+					hdr,
+					rcv_flags,
+					qp);
+				break;
+			default:
+				/* For now don't handle any other QP types */
+				break;
+			}
+
+			spin_unlock(&qp->r_lock);
+			/*
+			 * Notify hfi1_destroy_qp() if it is waiting
+			 * for us to finish.
+			 */
+			if (atomic_dec_and_test(&qp->refcount))
+				wake_up(&qp->wait);
+		} /* Unicast QP */
+	} /* Valid packet with TIDErr */
+
+	/* handle "RcvTypeErr" flags */
+	switch (rte) {
+	case RHF_RTE_ERROR_OP_CODE_ERR:
+	{
+		u32 opcode;
+		void *ebuf = NULL;
+		__be32 *bth = NULL;
+
+		if (rhf_use_egr_bfr(packet->rhf))
+			ebuf = packet->ebuf;
+
+		if (ebuf == NULL)
+			goto drop; /* this should never happen */
+
+		if (lnh == HFI1_LRH_BTH)
+			bth = (__be32 *)ebuf;
+		else if (lnh == HFI1_LRH_GRH)
+			bth = (__be32 *)((char *)ebuf + sizeof(struct ib_grh));
+		else
+			goto drop;
+
+		opcode = be32_to_cpu(bth[0]) >> 24;
+		opcode &= 0xff;
+
+		if (opcode == CNP_OPCODE) {
+			/*
+			 * Only in pre-B0 h/w is the CNP_OPCODE handled
+			 * via this code path (errata 291394).
+			 */
+			struct hfi1_qp *qp = NULL;
+			u32 lqpn, rqpn;
+			u16 rlid;
+			u8 svc_type, sl, sc5;
+
+			sc5  = (be16_to_cpu(rhdr->lrh[0]) >> 4) & 0xf;
+			if (rhf_dc_info(packet->rhf))
+				sc5 |= 0x10;
+			sl = ibp->sc_to_sl[sc5];
+
+			lqpn = be32_to_cpu(bth[1]) & HFI1_QPN_MASK;
+			qp = hfi1_lookup_qpn(ibp, lqpn);
+			if (qp == NULL)
+				goto drop;
+
+			switch (qp->ibqp.qp_type) {
+			case IB_QPT_UD:
+				rlid = 0;
+				rqpn = 0;
+				svc_type = IB_CC_SVCTYPE_UD;
+				break;
+			case IB_QPT_UC:
+				rlid = be16_to_cpu(rhdr->lrh[3]);
+				rqpn = qp->remote_qpn;
+				svc_type = IB_CC_SVCTYPE_UC;
+				break;
+			default:
+				goto drop;
+			}
+			/* drop qp->refcount, wake waiters if it's 0 */
+			if (atomic_dec_and_test(&qp->refcount))
+				wake_up(&qp->wait);
+
+			process_becn(ppd, sl, rlid, lqpn, rqpn, svc_type);
+		}
+
+		packet->rhf &= ~RHF_RCV_TYPE_ERR_SMASK;
+		break;
+	}
+	default:
+		break;
+	}
+
+drop:
+	return;
+}
+
+static inline u32 init_packet(struct hfi1_ctxtdata *rcd,
+			      struct hfi1_packet *packet)
+{
+
+	packet->rsize = rcd->rcvhdrqentsize; /* words */
+	packet->maxcnt = rcd->rcvhdrq_cnt * packet->rsize; /* words */
+	packet->rcd = rcd;
+	packet->updegr = 0;
+	packet->etail = -1;
+	packet->rhf_addr = (__le32 *) rcd->rcvhdrq + rcd->head +
+			   rcd->dd->rhf_offset;
+	packet->rhf = rhf_to_cpu(packet->rhf_addr);
+	packet->rhqoff = rcd->head;
+	packet->numpkt = 1;
+	return packet->rhqoff;
+
+}
+
+#define RCV_PKT_OK 0x0
+#define RCV_PKT_MAX 0x1
+
+static inline int process_rcv_packet(struct hfi1_packet *packet)
+{
+	int ret = RCV_PKT_OK;
+
+	packet->hdr = hfi1_get_msgheader(packet->rcd->dd,
+					 packet->rhf_addr);
+	packet->hlen = (u8 *)packet->rhf_addr - (u8 *)packet->hdr;
+	packet->etype = rhf_rcv_type(packet->rhf);
+	/* total length */
+	packet->tlen = rhf_pkt_len(packet->rhf); /* in bytes */
+	packet->ebuf = NULL;
+
+	/*
+	 * Call a type specific handler for the packet. We
+	 * should be able to trust that etype won't be beyond
+	 * the range of valid indexes. If so something is really
+	 * wrong and we can probably just let things come
+	 * crashing down. There is no need to eat another
+	 * comparison in this performance critical code.
+	 */
+	packet->rcd->dd->rhf_rcv_function_map[packet->etype](packet);
+
+	/* Set up for the next packet */
+	packet->rhqoff += packet->rsize;
+	if (packet->rhqoff >= packet->maxcnt)
+		packet->rhqoff = 0;
+	if (packet->numpkt == MAX_PKT_RECV)
+		ret = RCV_PKT_MAX;
+
+	packet->rhf_addr = (__le32 *) packet->rcd->rcvhdrq + packet->rhqoff +
+				      packet->rcd->dd->rhf_offset;
+	packet->rhf = rhf_to_cpu(packet->rhf_addr);
+
+	packet->numpkt++;
+
+	return ret;
+}
+
+static inline void process_rcv_update(int last, struct hfi1_packet *packet)
+{
+	/*
+	 * Update head regs etc., every 16 packets, if not last pkt,
+	 * to help prevent rcvhdrq overflows, when many packets
+	 * are processed and queue is nearly full.
+	 * Don't request an interrupt for intermediate updates.
+	 */
+	if (!last && !(packet->numpkt & 0xf)) {
+		update_usrhead(packet->rcd, packet->rhqoff, packet->updegr,
+			       packet->etail, 0, 0);
+		packet->updegr = 0;
+	}
+}
+
+static inline void finish_packet(struct hfi1_packet *packet)
+{
+
+	/*
+	 * Nothing we need to free for the packet.
+	 *
+	 * The only thing we need to do is a final update and call for an
+	 * interrupt
+	 */
+	update_usrhead(packet->rcd, packet->rcd->head, packet->updegr,
+		       packet->etail, rcv_intr_dynamic, packet->numpkt);
+
+}
+
+static inline void process_rcv_qp_work(struct hfi1_packet *packet)
+{
+
+	struct hfi1_ctxtdata *rcd;
+	struct hfi1_qp *qp, *nqp;
+
+	rcd = packet->rcd;
+
+	/*
+	 * Notify hfi1_destroy_qp() if it is waiting
+	 * for lookaside_qp to finish.
+	 */
+	if (rcd->lookaside_qp) {
+		if (atomic_dec_and_test(&rcd->lookaside_qp->refcount))
+			wake_up(&rcd->lookaside_qp->wait);
+		rcd->lookaside_qp = NULL;
+	}
+
+	rcd->head = packet->rhqoff;
+
+	/*
+	 * Iterate over all QPs waiting to respond.
+	 * The list won't change since the IRQ is only run on one CPU.
+	 */
+	list_for_each_entry_safe(qp, nqp, &rcd->qp_wait_list, rspwait) {
+		list_del_init(&qp->rspwait);
+		if (qp->r_flags & HFI1_R_RSP_NAK) {
+			qp->r_flags &= ~HFI1_R_RSP_NAK;
+			hfi1_send_rc_ack(rcd, qp, 0);
+		}
+		if (qp->r_flags & HFI1_R_RSP_SEND) {
+			unsigned long flags;
+
+			qp->r_flags &= ~HFI1_R_RSP_SEND;
+			spin_lock_irqsave(&qp->s_lock, flags);
+			if (ib_hfi1_state_ops[qp->state] &
+					HFI1_PROCESS_OR_FLUSH_SEND)
+				hfi1_schedule_send(qp);
+			spin_unlock_irqrestore(&qp->s_lock, flags);
+		}
+		if (atomic_dec_and_test(&qp->refcount))
+			wake_up(&qp->wait);
+	}
+}
+
+/*
+ * Handle receive interrupts when using the no dma rtail option.
+ */
+void handle_receive_interrupt_nodma_rtail(struct hfi1_ctxtdata *rcd)
+{
+	u32 l, seq;
+	int last = 0;
+	struct hfi1_packet packet;
+
+	l = init_packet(rcd, &packet);
+	seq = rhf_rcv_seq(packet.rhf);
+	if (seq != rcd->seq_cnt)
+		goto bail;
+	packet.hdrqtail = 0;
+
+	while (!last) {
+		last = process_rcv_packet(&packet);
+		seq = rhf_rcv_seq(packet.rhf);
+		if (++rcd->seq_cnt > 13)
+			rcd->seq_cnt = 1;
+		if (seq != rcd->seq_cnt)
+			last = 1;
+		process_rcv_update(last, &packet);
+	}
+	process_rcv_qp_work(&packet);
+bail:
+	finish_packet(&packet);
+}
+
+void handle_receive_interrupt_dma_rtail(struct hfi1_ctxtdata *rcd)
+{
+	u32 l;
+	int last = 0;
+	struct hfi1_packet packet;
+
+	l = init_packet(rcd, &packet);
+	packet.hdrqtail = get_rcvhdrtail(rcd);
+	if (l == packet.hdrqtail)
+		goto bail;
+	smp_rmb();  /* prevent speculative reads of dma'ed hdrq */
+
+	while (!last) {
+		last = process_rcv_packet(&packet);
+		 if (packet.rhqoff == packet.hdrqtail)
+			last = 1;
+		process_rcv_update(last, &packet);
+	}
+	process_rcv_qp_work(&packet);
+bail:
+	finish_packet(&packet);
+
+}
+
+static inline void set_all_nodma_rtail(struct hfi1_devdata *dd)
+{
+	int i;
+
+	for (i = 0; i < dd->first_user_ctxt; i++)
+		dd->rcd[i]->do_interrupt =
+			&handle_receive_interrupt_nodma_rtail;
+}
+
+static inline void set_all_dma_rtail(struct hfi1_devdata *dd)
+{
+	int i;
+
+	for (i = 0; i < dd->first_user_ctxt; i++)
+		dd->rcd[i]->do_interrupt =
+			&handle_receive_interrupt_dma_rtail;
+}
+
+/*
+ * handle_receive_interrupt - receive a packet
+ * @rcd: the context
+ *
+ * Called from interrupt handler for errors or receive interrupt.
+ * This is the slow path interrupt handler.
+ */
+void handle_receive_interrupt(struct hfi1_ctxtdata *rcd)
+{
+
+	struct hfi1_devdata *dd = rcd->dd;
+	u32 l;
+	int last = 0, needset = 1;
+	struct hfi1_packet packet;
+
+	l = init_packet(rcd, &packet);
+
+	if (!HFI1_CAP_IS_KSET(DMA_RTAIL)) {
+		u32 seq = rhf_rcv_seq(packet.rhf);
+
+		if (seq != rcd->seq_cnt)
+			goto bail;
+		packet.hdrqtail = 0;
+	} else {
+		packet.hdrqtail = get_rcvhdrtail(rcd);
+		if (l == packet.hdrqtail)
+			goto bail;
+		smp_rmb();  /* prevent speculative reads of dma'ed hdrq */
+	}
+
+	while (!last) {
+
+		if (unlikely(dd->do_drop && atomic_xchg(&dd->drop_packet,
+			DROP_PACKET_OFF) == DROP_PACKET_ON)) {
+			dd->do_drop = 0;
+
+			/* On to the next packet */
+			packet.rhqoff += packet.rsize;
+			packet.rhf_addr = (__le32 *) rcd->rcvhdrq +
+					  packet.rhqoff +
+					  dd->rhf_offset;
+			packet.rhf = rhf_to_cpu(packet.rhf_addr);
+
+		} else {
+			last = process_rcv_packet(&packet);
+		}
+
+		if (!HFI1_CAP_IS_KSET(DMA_RTAIL)) {
+			u32 seq = rhf_rcv_seq(packet.rhf);
+
+			if (++rcd->seq_cnt > 13)
+				rcd->seq_cnt = 1;
+			if (seq != rcd->seq_cnt)
+				last = 1;
+			if (needset) {
+				dd_dev_info(dd,
+					"Switching to NO_DMA_RTAIL\n");
+				set_all_nodma_rtail(dd);
+				needset = 0;
+			}
+		} else {
+			if (packet.rhqoff == packet.hdrqtail)
+				last = 1;
+			if (needset) {
+				dd_dev_info(dd,
+					    "Switching to DMA_RTAIL\n");
+				set_all_dma_rtail(dd);
+				needset = 0;
+			}
+		}
+
+		process_rcv_update(last, &packet);
+	}
+
+	process_rcv_qp_work(&packet);
+
+bail:
+	/*
+	 * Always write head at end, and setup rcv interrupt, even
+	 * if no packets were processed.
+	 */
+	finish_packet(&packet);
+}
+
+/*
+ * Convert a given MTU size to the on-wire MAD packet enumeration.
+ * Return -1 if the size is invalid.
+ */
+int mtu_to_enum(u32 mtu, int default_if_bad)
+{
+	switch (mtu) {
+	case     0: return OPA_MTU_0;
+	case   256: return OPA_MTU_256;
+	case   512: return OPA_MTU_512;
+	case  1024: return OPA_MTU_1024;
+	case  2048: return OPA_MTU_2048;
+	case  4096: return OPA_MTU_4096;
+	case  8192: return OPA_MTU_8192;
+	case 10240: return OPA_MTU_10240;
+	}
+	return default_if_bad;
+}
+
+u16 enum_to_mtu(int mtu)
+{
+	switch (mtu) {
+	case OPA_MTU_0:     return 0;
+	case OPA_MTU_256:   return 256;
+	case OPA_MTU_512:   return 512;
+	case OPA_MTU_1024:  return 1024;
+	case OPA_MTU_2048:  return 2048;
+	case OPA_MTU_4096:  return 4096;
+	case OPA_MTU_8192:  return 8192;
+	case OPA_MTU_10240: return 10240;
+	default: return 0xffff;
+	}
+}
+
+/*
+ * set_mtu - set the MTU
+ * @ppd: the per port data
+ *
+ * We can handle "any" incoming size, the issue here is whether we
+ * need to restrict our outgoing size.  We do not deal with what happens
+ * to programs that are already running when the size changes.
+ */
+int set_mtu(struct hfi1_pportdata *ppd)
+{
+	struct hfi1_devdata *dd = ppd->dd;
+	int i, drain, ret = 0, is_up = 0;
+
+	ppd->ibmtu = 0;
+	for (i = 0; i < hfi1_num_vls(ppd->vls_supported); i++)
+		if (ppd->ibmtu < dd->vld[i].mtu)
+			ppd->ibmtu = dd->vld[i].mtu;
+	ppd->ibmaxlen = ppd->ibmtu + lrh_max_header_bytes(ppd->dd);
+
+	mutex_lock(&ppd->hls_lock);
+	if (ppd->host_link_state == HLS_UP_INIT
+			|| ppd->host_link_state == HLS_UP_ARMED
+			|| ppd->host_link_state == HLS_UP_ACTIVE)
+		is_up = 1;
+
+	drain = !is_ax(dd) && is_up;
+
+	if (drain)
+		/*
+		 * MTU is specified per-VL. To ensure that no packet gets
+		 * stuck (due, e.g., to the MTU for the packet's VL being
+		 * reduced), empty the per-VL FIFOs before adjusting MTU.
+		 */
+		ret = stop_drain_data_vls(dd);
+
+	if (ret) {
+		dd_dev_err(dd, "%s: cannot stop/drain VLs - refusing to change per-VL MTUs\n",
+			   __func__);
+		goto err;
+	}
+
+	hfi1_set_ib_cfg(ppd, HFI1_IB_CFG_MTU, 0);
+
+	if (drain)
+		open_fill_data_vls(dd); /* reopen all VLs */
+
+err:
+	mutex_unlock(&ppd->hls_lock);
+
+	return ret;
+}
+
+int hfi1_set_lid(struct hfi1_pportdata *ppd, u32 lid, u8 lmc)
+{
+	struct hfi1_devdata *dd = ppd->dd;
+
+	ppd->lid = lid;
+	ppd->lmc = lmc;
+	hfi1_set_ib_cfg(ppd, HFI1_IB_CFG_LIDLMC, 0);
+
+	dd_dev_info(dd, "IB%u:%u got a lid: 0x%x\n", dd->unit, ppd->port, lid);
+
+	return 0;
+}
+
+/*
+ * Following deal with the "obviously simple" task of overriding the state
+ * of the LEDs, which normally indicate link physical and logical status.
+ * The complications arise in dealing with different hardware mappings
+ * and the board-dependent routine being called from interrupts.
+ * and then there's the requirement to _flash_ them.
+ */
+#define LED_OVER_FREQ_SHIFT 8
+#define LED_OVER_FREQ_MASK (0xFF<<LED_OVER_FREQ_SHIFT)
+/* Below is "non-zero" to force override, but both actual LEDs are off */
+#define LED_OVER_BOTH_OFF (8)
+
+static void run_led_override(unsigned long opaque)
+{
+	struct hfi1_pportdata *ppd = (struct hfi1_pportdata *)opaque;
+	struct hfi1_devdata *dd = ppd->dd;
+	int timeoff;
+	int ph_idx;
+
+	if (!(dd->flags & HFI1_INITTED))
+		return;
+
+	ph_idx = ppd->led_override_phase++ & 1;
+	ppd->led_override = ppd->led_override_vals[ph_idx];
+	timeoff = ppd->led_override_timeoff;
+
+	/*
+	 * don't re-fire the timer if user asked for it to be off; we let
+	 * it fire one more time after they turn it off to simplify
+	 */
+	if (ppd->led_override_vals[0] || ppd->led_override_vals[1])
+		mod_timer(&ppd->led_override_timer, jiffies + timeoff);
+}
+
+void hfi1_set_led_override(struct hfi1_pportdata *ppd, unsigned int val)
+{
+	struct hfi1_devdata *dd = ppd->dd;
+	int timeoff, freq;
+
+	if (!(dd->flags & HFI1_INITTED))
+		return;
+
+	/* First check if we are blinking. If not, use 1HZ polling */
+	timeoff = HZ;
+	freq = (val & LED_OVER_FREQ_MASK) >> LED_OVER_FREQ_SHIFT;
+
+	if (freq) {
+		/* For blink, set each phase from one nybble of val */
+		ppd->led_override_vals[0] = val & 0xF;
+		ppd->led_override_vals[1] = (val >> 4) & 0xF;
+		timeoff = (HZ << 4)/freq;
+	} else {
+		/* Non-blink set both phases the same. */
+		ppd->led_override_vals[0] = val & 0xF;
+		ppd->led_override_vals[1] = val & 0xF;
+	}
+	ppd->led_override_timeoff = timeoff;
+
+	/*
+	 * If the timer has not already been started, do so. Use a "quick"
+	 * timeout so the function will be called soon, to look at our request.
+	 */
+	if (atomic_inc_return(&ppd->led_override_timer_active) == 1) {
+		/* Need to start timer */
+		init_timer(&ppd->led_override_timer);
+		ppd->led_override_timer.function = run_led_override;
+		ppd->led_override_timer.data = (unsigned long) ppd;
+		ppd->led_override_timer.expires = jiffies + 1;
+		add_timer(&ppd->led_override_timer);
+	} else {
+		if (ppd->led_override_vals[0] || ppd->led_override_vals[1])
+			mod_timer(&ppd->led_override_timer, jiffies + 1);
+		atomic_dec(&ppd->led_override_timer_active);
+	}
+}
+
+/**
+ * hfi1_reset_device - reset the chip if possible
+ * @unit: the device to reset
+ *
+ * Whether or not reset is successful, we attempt to re-initialize the chip
+ * (that is, much like a driver unload/reload).  We clear the INITTED flag
+ * so that the various entry points will fail until we reinitialize.  For
+ * now, we only allow this if no user contexts are open that use chip resources
+ */
+int hfi1_reset_device(int unit)
+{
+	int ret, i;
+	struct hfi1_devdata *dd = hfi1_lookup(unit);
+	struct hfi1_pportdata *ppd;
+	unsigned long flags;
+	int pidx;
+
+	if (!dd) {
+		ret = -ENODEV;
+		goto bail;
+	}
+
+	dd_dev_info(dd, "Reset on unit %u requested\n", unit);
+
+	if (!dd->kregbase || !(dd->flags & HFI1_PRESENT)) {
+		dd_dev_info(dd,
+			"Invalid unit number %u or not initialized or not present\n",
+			unit);
+		ret = -ENXIO;
+		goto bail;
+	}
+
+	spin_lock_irqsave(&dd->uctxt_lock, flags);
+	if (dd->rcd)
+		for (i = dd->first_user_ctxt; i < dd->num_rcv_contexts; i++) {
+			if (!dd->rcd[i] || !dd->rcd[i]->cnt)
+				continue;
+			spin_unlock_irqrestore(&dd->uctxt_lock, flags);
+			ret = -EBUSY;
+			goto bail;
+		}
+	spin_unlock_irqrestore(&dd->uctxt_lock, flags);
+
+	for (pidx = 0; pidx < dd->num_pports; ++pidx) {
+		ppd = dd->pport + pidx;
+		if (atomic_read(&ppd->led_override_timer_active)) {
+			/* Need to stop LED timer, _then_ shut off LEDs */
+			del_timer_sync(&ppd->led_override_timer);
+			atomic_set(&ppd->led_override_timer_active, 0);
+		}
+
+		/* Shut off LEDs after we are sure timer is not running */
+		ppd->led_override = LED_OVER_BOTH_OFF;
+	}
+	if (dd->flags & HFI1_HAS_SEND_DMA)
+		sdma_exit(dd);
+
+	hfi1_reset_cpu_counters(dd);
+
+	ret = hfi1_init(dd, 1);
+
+	if (ret)
+		dd_dev_err(dd,
+			"Reinitialize unit %u after reset failed with %d\n",
+			unit, ret);
+	else
+		dd_dev_info(dd, "Reinitialized unit %u after resetting\n",
+			unit);
+
+bail:
+	return ret;
+}
+
+void handle_eflags(struct hfi1_packet *packet)
+{
+	struct hfi1_ctxtdata *rcd = packet->rcd;
+	u32 rte = rhf_rcv_type_err(packet->rhf);
+
+	dd_dev_err(rcd->dd,
+		"receive context %d: rhf 0x%016llx, errs [ %s%s%s%s%s%s%s%s] rte 0x%x\n",
+		rcd->ctxt, packet->rhf,
+		packet->rhf & RHF_K_HDR_LEN_ERR ? "k_hdr_len " : "",
+		packet->rhf & RHF_DC_UNC_ERR ? "dc_unc " : "",
+		packet->rhf & RHF_DC_ERR ? "dc " : "",
+		packet->rhf & RHF_TID_ERR ? "tid " : "",
+		packet->rhf & RHF_LEN_ERR ? "len " : "",
+		packet->rhf & RHF_ECC_ERR ? "ecc " : "",
+		packet->rhf & RHF_VCRC_ERR ? "vcrc " : "",
+		packet->rhf & RHF_ICRC_ERR ? "icrc " : "",
+		rte);
+
+	rcv_hdrerr(rcd, rcd->ppd, packet);
+}
+
+/*
+ * The following functions are called by the interrupt handler. They are type
+ * specific handlers for each packet type.
+ */
+int process_receive_ib(struct hfi1_packet *packet)
+{
+	trace_hfi1_rcvhdr(packet->rcd->ppd->dd,
+			  packet->rcd->ctxt,
+			  rhf_err_flags(packet->rhf),
+			  RHF_RCV_TYPE_IB,
+			  packet->hlen,
+			  packet->tlen,
+			  packet->updegr,
+			  rhf_egr_index(packet->rhf));
+
+	if (unlikely(rhf_err_flags(packet->rhf))) {
+		handle_eflags(packet);
+		return RHF_RCV_CONTINUE;
+	}
+
+	/* retrieve eager buffer details */
+	if (rhf_use_egr_bfr(packet->rhf)) {
+		packet->etail = rhf_egr_index(packet->rhf);
+		packet->ebuf = get_egrbuf(packet->rcd, packet->rhf,
+				 &packet->updegr);
+		/*
+		 * Prefetch the contents of the eager buffer.  It is
+		 * OK to send a negative length to prefetch_range().
+		 * The +2 is the size of the RHF.
+		 */
+		prefetch_range(packet->ebuf,
+			packet->tlen - ((packet->rcd->rcvhdrqentsize -
+				  (rhf_hdrq_offset(packet->rhf)+2)) * 4));
+	}
+
+
+	hfi1_ib_rcv(packet);
+	return RHF_RCV_CONTINUE;
+}
+
+int process_receive_bypass(struct hfi1_packet *packet)
+{
+	if (unlikely(rhf_err_flags(packet->rhf)))
+		handle_eflags(packet);
+
+	dd_dev_err(packet->rcd->dd,
+	   "Bypass packets are not supported in normal operation. Dropping\n");
+	return RHF_RCV_CONTINUE;
+}
+
+int process_receive_error(struct hfi1_packet *packet)
+{
+	handle_eflags(packet);
+	dd_dev_err(packet->rcd->dd,
+		   "Unhandled error packet received. Dropping.\n");
+	return RHF_RCV_CONTINUE;
+}
+
+int kdeth_process_expected(struct hfi1_packet *packet)
+{
+	if (unlikely(rhf_err_flags(packet->rhf)))
+		handle_eflags(packet);
+
+	dd_dev_err(packet->rcd->dd,
+		   "Unhandled expected packet received. Dropping.\n");
+	return RHF_RCV_CONTINUE;
+}
+
+int kdeth_process_eager(struct hfi1_packet *packet)
+{
+	if (unlikely(rhf_err_flags(packet->rhf)))
+		handle_eflags(packet);
+
+	dd_dev_err(packet->rcd->dd,
+		   "Unhandled eager packet received. Dropping.\n");
+	return RHF_RCV_CONTINUE;
+}
+
+int process_receive_invalid(struct hfi1_packet *packet)
+{
+	dd_dev_err(packet->rcd->dd, "Invalid packet type %d. Dropping\n",
+		rhf_rcv_type(packet->rhf));
+	return RHF_RCV_CONTINUE;
+}