[SCSI] csiostor: Chelsio FCoE offload driver

Signed-off-by: Naresh Kumar Inna <naresh@chelsio.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/csiostor/csio_wr.c b/drivers/scsi/csiostor/csio_wr.c
new file mode 100644
index 0000000..c32df1b
--- /dev/null
+++ b/drivers/scsi/csiostor/csio_wr.c
@@ -0,0 +1,1632 @@
+/*
+ * This file is part of the Chelsio FCoE driver for Linux.
+ *
+ * Copyright (c) 2008-2012 Chelsio Communications, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     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.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/compiler.h>
+#include <linux/slab.h>
+#include <asm/page.h>
+#include <linux/cache.h>
+
+#include "csio_hw.h"
+#include "csio_wr.h"
+#include "csio_mb.h"
+#include "csio_defs.h"
+
+int csio_intr_coalesce_cnt;		/* value:SGE_INGRESS_RX_THRESHOLD[0] */
+static int csio_sge_thresh_reg;		/* SGE_INGRESS_RX_THRESHOLD[0] */
+
+int csio_intr_coalesce_time = 10;	/* value:SGE_TIMER_VALUE_1 */
+static int csio_sge_timer_reg = 1;
+
+#define CSIO_SET_FLBUF_SIZE(_hw, _reg, _val)				\
+	csio_wr_reg32((_hw), (_val), SGE_FL_BUFFER_SIZE##_reg)
+
+static void
+csio_get_flbuf_size(struct csio_hw *hw, struct csio_sge *sge, uint32_t reg)
+{
+	sge->sge_fl_buf_size[reg] = csio_rd_reg32(hw, SGE_FL_BUFFER_SIZE0 +
+							reg * sizeof(uint32_t));
+}
+
+/* Free list buffer size */
+static inline uint32_t
+csio_wr_fl_bufsz(struct csio_sge *sge, struct csio_dma_buf *buf)
+{
+	return sge->sge_fl_buf_size[buf->paddr & 0xF];
+}
+
+/* Size of the egress queue status page */
+static inline uint32_t
+csio_wr_qstat_pgsz(struct csio_hw *hw)
+{
+	return (hw->wrm.sge.sge_control & EGRSTATUSPAGESIZE(1)) ?  128 : 64;
+}
+
+/* Ring freelist doorbell */
+static inline void
+csio_wr_ring_fldb(struct csio_hw *hw, struct csio_q *flq)
+{
+	/*
+	 * Ring the doorbell only when we have atleast CSIO_QCREDIT_SZ
+	 * number of bytes in the freelist queue. This translates to atleast
+	 * 8 freelist buffer pointers (since each pointer is 8 bytes).
+	 */
+	if (flq->inc_idx >= 8) {
+		csio_wr_reg32(hw, DBPRIO(1) | QID(flq->un.fl.flid) |
+			      PIDX(flq->inc_idx / 8),
+			      MYPF_REG(SGE_PF_KDOORBELL));
+		flq->inc_idx &= 7;
+	}
+}
+
+/* Write a 0 cidx increment value to enable SGE interrupts for this queue */
+static void
+csio_wr_sge_intr_enable(struct csio_hw *hw, uint16_t iqid)
+{
+	csio_wr_reg32(hw, CIDXINC(0)		|
+			  INGRESSQID(iqid)	|
+			  TIMERREG(X_TIMERREG_RESTART_COUNTER),
+			  MYPF_REG(SGE_PF_GTS));
+}
+
+/*
+ * csio_wr_fill_fl - Populate the FL buffers of a FL queue.
+ * @hw: HW module.
+ * @flq: Freelist queue.
+ *
+ * Fill up freelist buffer entries with buffers of size specified
+ * in the size register.
+ *
+ */
+static int
+csio_wr_fill_fl(struct csio_hw *hw, struct csio_q *flq)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_sge *sge = &wrm->sge;
+	__be64 *d = (__be64 *)(flq->vstart);
+	struct csio_dma_buf *buf = &flq->un.fl.bufs[0];
+	uint64_t paddr;
+	int sreg = flq->un.fl.sreg;
+	int n = flq->credits;
+
+	while (n--) {
+		buf->len = sge->sge_fl_buf_size[sreg];
+		buf->vaddr = pci_alloc_consistent(hw->pdev, buf->len,
+						  &buf->paddr);
+		if (!buf->vaddr) {
+			csio_err(hw, "Could only fill %d buffers!\n", n + 1);
+			return -ENOMEM;
+		}
+
+		paddr = buf->paddr | (sreg & 0xF);
+
+		*d++ = cpu_to_be64(paddr);
+		buf++;
+	}
+
+	return 0;
+}
+
+/*
+ * csio_wr_update_fl -
+ * @hw: HW module.
+ * @flq: Freelist queue.
+ *
+ *
+ */
+static inline void
+csio_wr_update_fl(struct csio_hw *hw, struct csio_q *flq, uint16_t n)
+{
+
+	flq->inc_idx += n;
+	flq->pidx += n;
+	if (unlikely(flq->pidx >= flq->credits))
+		flq->pidx -= (uint16_t)flq->credits;
+
+	CSIO_INC_STATS(flq, n_flq_refill);
+}
+
+/*
+ * csio_wr_alloc_q - Allocate a WR queue and initialize it.
+ * @hw: HW module
+ * @qsize: Size of the queue in bytes
+ * @wrsize: Since of WR in this queue, if fixed.
+ * @type: Type of queue (Ingress/Egress/Freelist)
+ * @owner: Module that owns this queue.
+ * @nflb: Number of freelist buffers for FL.
+ * @sreg: What is the FL buffer size register?
+ * @iq_int_handler: Ingress queue handler in INTx mode.
+ *
+ * This function allocates and sets up a queue for the caller
+ * of size qsize, aligned at the required boundary. This is subject to
+ * be free entries being available in the queue array. If one is found,
+ * it is initialized with the allocated queue, marked as being used (owner),
+ * and a handle returned to the caller in form of the queue's index
+ * into the q_arr array.
+ * If user has indicated a freelist (by specifying nflb > 0), create
+ * another queue (with its own index into q_arr) for the freelist. Allocate
+ * memory for DMA buffer metadata (vaddr, len etc). Save off the freelist
+ * idx in the ingress queue's flq.idx. This is how a Freelist is associated
+ * with its owning ingress queue.
+ */
+int
+csio_wr_alloc_q(struct csio_hw *hw, uint32_t qsize, uint32_t wrsize,
+		uint16_t type, void *owner, uint32_t nflb, int sreg,
+		iq_handler_t iq_intx_handler)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_q	*q, *flq;
+	int		free_idx = wrm->free_qidx;
+	int		ret_idx = free_idx;
+	uint32_t	qsz;
+	int flq_idx;
+
+	if (free_idx >= wrm->num_q) {
+		csio_err(hw, "No more free queues.\n");
+		return -1;
+	}
+
+	switch (type) {
+	case CSIO_EGRESS:
+		qsz = ALIGN(qsize, CSIO_QCREDIT_SZ) + csio_wr_qstat_pgsz(hw);
+		break;
+	case CSIO_INGRESS:
+		switch (wrsize) {
+		case 16:
+		case 32:
+		case 64:
+		case 128:
+			break;
+		default:
+			csio_err(hw, "Invalid Ingress queue WR size:%d\n",
+				    wrsize);
+			return -1;
+		}
+
+		/*
+		 * Number of elements must be a multiple of 16
+		 * So this includes status page size
+		 */
+		qsz = ALIGN(qsize/wrsize, 16) * wrsize;
+
+		break;
+	case CSIO_FREELIST:
+		qsz = ALIGN(qsize/wrsize, 8) * wrsize + csio_wr_qstat_pgsz(hw);
+		break;
+	default:
+		csio_err(hw, "Invalid queue type: 0x%x\n", type);
+		return -1;
+	}
+
+	q = wrm->q_arr[free_idx];
+
+	q->vstart = pci_alloc_consistent(hw->pdev, qsz, &q->pstart);
+	if (!q->vstart) {
+		csio_err(hw,
+			 "Failed to allocate DMA memory for "
+			 "queue at id: %d size: %d\n", free_idx, qsize);
+		return -1;
+	}
+
+	/*
+	 * We need to zero out the contents, importantly for ingress,
+	 * since we start with a generatiom bit of 1 for ingress.
+	 */
+	memset(q->vstart, 0, qsz);
+
+	q->type		= type;
+	q->owner	= owner;
+	q->pidx		= q->cidx = q->inc_idx = 0;
+	q->size		= qsz;
+	q->wr_sz	= wrsize;	/* If using fixed size WRs */
+
+	wrm->free_qidx++;
+
+	if (type == CSIO_INGRESS) {
+		/* Since queue area is set to zero */
+		q->un.iq.genbit	= 1;
+
+		/*
+		 * Ingress queue status page size is always the size of
+		 * the ingress queue entry.
+		 */
+		q->credits	= (qsz - q->wr_sz) / q->wr_sz;
+		q->vwrap	= (void *)((uintptr_t)(q->vstart) + qsz
+							- q->wr_sz);
+
+		/* Allocate memory for FL if requested */
+		if (nflb > 0) {
+			flq_idx = csio_wr_alloc_q(hw, nflb * sizeof(__be64),
+						  sizeof(__be64), CSIO_FREELIST,
+						  owner, 0, sreg, NULL);
+			if (flq_idx == -1) {
+				csio_err(hw,
+					 "Failed to allocate FL queue"
+					 " for IQ idx:%d\n", free_idx);
+				return -1;
+			}
+
+			/* Associate the new FL with the Ingress quue */
+			q->un.iq.flq_idx = flq_idx;
+
+			flq = wrm->q_arr[q->un.iq.flq_idx];
+			flq->un.fl.bufs = kzalloc(flq->credits *
+						  sizeof(struct csio_dma_buf),
+						  GFP_KERNEL);
+			if (!flq->un.fl.bufs) {
+				csio_err(hw,
+					 "Failed to allocate FL queue bufs"
+					 " for IQ idx:%d\n", free_idx);
+				return -1;
+			}
+
+			flq->un.fl.packen = 0;
+			flq->un.fl.offset = 0;
+			flq->un.fl.sreg = sreg;
+
+			/* Fill up the free list buffers */
+			if (csio_wr_fill_fl(hw, flq))
+				return -1;
+
+			/*
+			 * Make sure in a FLQ, atleast 1 credit (8 FL buffers)
+			 * remains unpopulated,otherwise HW thinks
+			 * FLQ is empty.
+			 */
+			flq->pidx = flq->inc_idx = flq->credits - 8;
+		} else {
+			q->un.iq.flq_idx = -1;
+		}
+
+		/* Associate the IQ INTx handler. */
+		q->un.iq.iq_intx_handler = iq_intx_handler;
+
+		csio_q_iqid(hw, ret_idx) = CSIO_MAX_QID;
+
+	} else if (type == CSIO_EGRESS) {
+		q->credits = (qsz - csio_wr_qstat_pgsz(hw)) / CSIO_QCREDIT_SZ;
+		q->vwrap   = (void *)((uintptr_t)(q->vstart) + qsz
+						- csio_wr_qstat_pgsz(hw));
+		csio_q_eqid(hw, ret_idx) = CSIO_MAX_QID;
+	} else { /* Freelist */
+		q->credits = (qsz - csio_wr_qstat_pgsz(hw)) / sizeof(__be64);
+		q->vwrap   = (void *)((uintptr_t)(q->vstart) + qsz
+						- csio_wr_qstat_pgsz(hw));
+		csio_q_flid(hw, ret_idx) = CSIO_MAX_QID;
+	}
+
+	return ret_idx;
+}
+
+/*
+ * csio_wr_iq_create_rsp - Response handler for IQ creation.
+ * @hw: The HW module.
+ * @mbp: Mailbox.
+ * @iq_idx: Ingress queue that got created.
+ *
+ * Handle FW_IQ_CMD mailbox completion. Save off the assigned IQ/FL ids.
+ */
+static int
+csio_wr_iq_create_rsp(struct csio_hw *hw, struct csio_mb *mbp, int iq_idx)
+{
+	struct csio_iq_params iqp;
+	enum fw_retval retval;
+	uint32_t iq_id;
+	int flq_idx;
+
+	memset(&iqp, 0, sizeof(struct csio_iq_params));
+
+	csio_mb_iq_alloc_write_rsp(hw, mbp, &retval, &iqp);
+
+	if (retval != FW_SUCCESS) {
+		csio_err(hw, "IQ cmd returned 0x%x!\n", retval);
+		mempool_free(mbp, hw->mb_mempool);
+		return -EINVAL;
+	}
+
+	csio_q_iqid(hw, iq_idx)		= iqp.iqid;
+	csio_q_physiqid(hw, iq_idx)	= iqp.physiqid;
+	csio_q_pidx(hw, iq_idx)		= csio_q_cidx(hw, iq_idx) = 0;
+	csio_q_inc_idx(hw, iq_idx)	= 0;
+
+	/* Actual iq-id. */
+	iq_id = iqp.iqid - hw->wrm.fw_iq_start;
+
+	/* Set the iq-id to iq map table. */
+	if (iq_id >= CSIO_MAX_IQ) {
+		csio_err(hw,
+			 "Exceeding MAX_IQ(%d) supported!"
+			 " iqid:%d rel_iqid:%d FW iq_start:%d\n",
+			 CSIO_MAX_IQ, iq_id, iqp.iqid, hw->wrm.fw_iq_start);
+		mempool_free(mbp, hw->mb_mempool);
+		return -EINVAL;
+	}
+	csio_q_set_intr_map(hw, iq_idx, iq_id);
+
+	/*
+	 * During FW_IQ_CMD, FW sets interrupt_sent bit to 1 in the SGE
+	 * ingress context of this queue. This will block interrupts to
+	 * this queue until the next GTS write. Therefore, we do a
+	 * 0-cidx increment GTS write for this queue just to clear the
+	 * interrupt_sent bit. This will re-enable interrupts to this
+	 * queue.
+	 */
+	csio_wr_sge_intr_enable(hw, iqp.physiqid);
+
+	flq_idx = csio_q_iq_flq_idx(hw, iq_idx);
+	if (flq_idx != -1) {
+		struct csio_q *flq = hw->wrm.q_arr[flq_idx];
+
+		csio_q_flid(hw, flq_idx) = iqp.fl0id;
+		csio_q_cidx(hw, flq_idx) = 0;
+		csio_q_pidx(hw, flq_idx)    = csio_q_credits(hw, flq_idx) - 8;
+		csio_q_inc_idx(hw, flq_idx) = csio_q_credits(hw, flq_idx) - 8;
+
+		/* Now update SGE about the buffers allocated during init */
+		csio_wr_ring_fldb(hw, flq);
+	}
+
+	mempool_free(mbp, hw->mb_mempool);
+
+	return 0;
+}
+
+/*
+ * csio_wr_iq_create - Configure an Ingress queue with FW.
+ * @hw: The HW module.
+ * @priv: Private data object.
+ * @iq_idx: Ingress queue index in the WR module.
+ * @vec: MSIX vector.
+ * @portid: PCIE Channel to be associated with this queue.
+ * @async: Is this a FW asynchronous message handling queue?
+ * @cbfn: Completion callback.
+ *
+ * This API configures an ingress queue with FW by issuing a FW_IQ_CMD mailbox
+ * with alloc/write bits set.
+ */
+int
+csio_wr_iq_create(struct csio_hw *hw, void *priv, int iq_idx,
+		  uint32_t vec, uint8_t portid, bool async,
+		  void (*cbfn) (struct csio_hw *, struct csio_mb *))
+{
+	struct csio_mb  *mbp;
+	struct csio_iq_params iqp;
+	int flq_idx;
+
+	memset(&iqp, 0, sizeof(struct csio_iq_params));
+	csio_q_portid(hw, iq_idx) = portid;
+
+	mbp = mempool_alloc(hw->mb_mempool, GFP_ATOMIC);
+	if (!mbp) {
+		csio_err(hw, "IQ command out of memory!\n");
+		return -ENOMEM;
+	}
+
+	switch (hw->intr_mode) {
+	case CSIO_IM_INTX:
+	case CSIO_IM_MSI:
+		/* For interrupt forwarding queue only */
+		if (hw->intr_iq_idx == iq_idx)
+			iqp.iqandst	= X_INTERRUPTDESTINATION_PCIE;
+		else
+			iqp.iqandst	= X_INTERRUPTDESTINATION_IQ;
+		iqp.iqandstindex	=
+			csio_q_physiqid(hw, hw->intr_iq_idx);
+		break;
+	case CSIO_IM_MSIX:
+		iqp.iqandst		= X_INTERRUPTDESTINATION_PCIE;
+		iqp.iqandstindex	= (uint16_t)vec;
+		break;
+	case CSIO_IM_NONE:
+		mempool_free(mbp, hw->mb_mempool);
+		return -EINVAL;
+	}
+
+	/* Pass in the ingress queue cmd parameters */
+	iqp.pfn			= hw->pfn;
+	iqp.vfn			= 0;
+	iqp.iq_start		= 1;
+	iqp.viid		= 0;
+	iqp.type		= FW_IQ_TYPE_FL_INT_CAP;
+	iqp.iqasynch		= async;
+	if (csio_intr_coalesce_cnt)
+		iqp.iqanus	= X_UPDATESCHEDULING_COUNTER_OPTTIMER;
+	else
+		iqp.iqanus	= X_UPDATESCHEDULING_TIMER;
+	iqp.iqanud		= X_UPDATEDELIVERY_INTERRUPT;
+	iqp.iqpciech		= portid;
+	iqp.iqintcntthresh	= (uint8_t)csio_sge_thresh_reg;
+
+	switch (csio_q_wr_sz(hw, iq_idx)) {
+	case 16:
+		iqp.iqesize = 0; break;
+	case 32:
+		iqp.iqesize = 1; break;
+	case 64:
+		iqp.iqesize = 2; break;
+	case 128:
+		iqp.iqesize = 3; break;
+	}
+
+	iqp.iqsize		= csio_q_size(hw, iq_idx) /
+						csio_q_wr_sz(hw, iq_idx);
+	iqp.iqaddr		= csio_q_pstart(hw, iq_idx);
+
+	flq_idx = csio_q_iq_flq_idx(hw, iq_idx);
+	if (flq_idx != -1) {
+		struct csio_q *flq = hw->wrm.q_arr[flq_idx];
+
+		iqp.fl0paden	= 1;
+		iqp.fl0packen	= flq->un.fl.packen ? 1 : 0;
+		iqp.fl0fbmin	= X_FETCHBURSTMIN_64B;
+		iqp.fl0fbmax	= X_FETCHBURSTMAX_512B;
+		iqp.fl0size	= csio_q_size(hw, flq_idx) / CSIO_QCREDIT_SZ;
+		iqp.fl0addr	= csio_q_pstart(hw, flq_idx);
+	}
+
+	csio_mb_iq_alloc_write(hw, mbp, priv, CSIO_MB_DEFAULT_TMO, &iqp, cbfn);
+
+	if (csio_mb_issue(hw, mbp)) {
+		csio_err(hw, "Issue of IQ cmd failed!\n");
+		mempool_free(mbp, hw->mb_mempool);
+		return -EINVAL;
+	}
+
+	if (cbfn != NULL)
+		return 0;
+
+	return csio_wr_iq_create_rsp(hw, mbp, iq_idx);
+}
+
+/*
+ * csio_wr_eq_create_rsp - Response handler for EQ creation.
+ * @hw: The HW module.
+ * @mbp: Mailbox.
+ * @eq_idx: Egress queue that got created.
+ *
+ * Handle FW_EQ_OFLD_CMD mailbox completion. Save off the assigned EQ ids.
+ */
+static int
+csio_wr_eq_cfg_rsp(struct csio_hw *hw, struct csio_mb *mbp, int eq_idx)
+{
+	struct csio_eq_params eqp;
+	enum fw_retval retval;
+
+	memset(&eqp, 0, sizeof(struct csio_eq_params));
+
+	csio_mb_eq_ofld_alloc_write_rsp(hw, mbp, &retval, &eqp);
+
+	if (retval != FW_SUCCESS) {
+		csio_err(hw, "EQ OFLD cmd returned 0x%x!\n", retval);
+		mempool_free(mbp, hw->mb_mempool);
+		return -EINVAL;
+	}
+
+	csio_q_eqid(hw, eq_idx)	= (uint16_t)eqp.eqid;
+	csio_q_physeqid(hw, eq_idx) = (uint16_t)eqp.physeqid;
+	csio_q_pidx(hw, eq_idx)	= csio_q_cidx(hw, eq_idx) = 0;
+	csio_q_inc_idx(hw, eq_idx) = 0;
+
+	mempool_free(mbp, hw->mb_mempool);
+
+	return 0;
+}
+
+/*
+ * csio_wr_eq_create - Configure an Egress queue with FW.
+ * @hw: HW module.
+ * @priv: Private data.
+ * @eq_idx: Egress queue index in the WR module.
+ * @iq_idx: Associated ingress queue index.
+ * @cbfn: Completion callback.
+ *
+ * This API configures a offload egress queue with FW by issuing a
+ * FW_EQ_OFLD_CMD  (with alloc + write ) mailbox.
+ */
+int
+csio_wr_eq_create(struct csio_hw *hw, void *priv, int eq_idx,
+		  int iq_idx, uint8_t portid,
+		  void (*cbfn) (struct csio_hw *, struct csio_mb *))
+{
+	struct csio_mb  *mbp;
+	struct csio_eq_params eqp;
+
+	memset(&eqp, 0, sizeof(struct csio_eq_params));
+
+	mbp = mempool_alloc(hw->mb_mempool, GFP_ATOMIC);
+	if (!mbp) {
+		csio_err(hw, "EQ command out of memory!\n");
+		return -ENOMEM;
+	}
+
+	eqp.pfn			= hw->pfn;
+	eqp.vfn			= 0;
+	eqp.eqstart		= 1;
+	eqp.hostfcmode		= X_HOSTFCMODE_STATUS_PAGE;
+	eqp.iqid		= csio_q_iqid(hw, iq_idx);
+	eqp.fbmin		= X_FETCHBURSTMIN_64B;
+	eqp.fbmax		= X_FETCHBURSTMAX_512B;
+	eqp.cidxfthresh		= 0;
+	eqp.pciechn		= portid;
+	eqp.eqsize		= csio_q_size(hw, eq_idx) / CSIO_QCREDIT_SZ;
+	eqp.eqaddr		= csio_q_pstart(hw, eq_idx);
+
+	csio_mb_eq_ofld_alloc_write(hw, mbp, priv, CSIO_MB_DEFAULT_TMO,
+				    &eqp, cbfn);
+
+	if (csio_mb_issue(hw, mbp)) {
+		csio_err(hw, "Issue of EQ OFLD cmd failed!\n");
+		mempool_free(mbp, hw->mb_mempool);
+		return -EINVAL;
+	}
+
+	if (cbfn != NULL)
+		return 0;
+
+	return csio_wr_eq_cfg_rsp(hw, mbp, eq_idx);
+}
+
+/*
+ * csio_wr_iq_destroy_rsp - Response handler for IQ removal.
+ * @hw: The HW module.
+ * @mbp: Mailbox.
+ * @iq_idx: Ingress queue that was freed.
+ *
+ * Handle FW_IQ_CMD (free) mailbox completion.
+ */
+static int
+csio_wr_iq_destroy_rsp(struct csio_hw *hw, struct csio_mb *mbp, int iq_idx)
+{
+	enum fw_retval retval = csio_mb_fw_retval(mbp);
+	int rv = 0;
+
+	if (retval != FW_SUCCESS)
+		rv = -EINVAL;
+
+	mempool_free(mbp, hw->mb_mempool);
+
+	return rv;
+}
+
+/*
+ * csio_wr_iq_destroy - Free an ingress queue.
+ * @hw: The HW module.
+ * @priv: Private data object.
+ * @iq_idx: Ingress queue index to destroy
+ * @cbfn: Completion callback.
+ *
+ * This API frees an ingress queue by issuing the FW_IQ_CMD
+ * with the free bit set.
+ */
+static int
+csio_wr_iq_destroy(struct csio_hw *hw, void *priv, int iq_idx,
+		   void (*cbfn)(struct csio_hw *, struct csio_mb *))
+{
+	int rv = 0;
+	struct csio_mb  *mbp;
+	struct csio_iq_params iqp;
+	int flq_idx;
+
+	memset(&iqp, 0, sizeof(struct csio_iq_params));
+
+	mbp = mempool_alloc(hw->mb_mempool, GFP_ATOMIC);
+	if (!mbp)
+		return -ENOMEM;
+
+	iqp.pfn		= hw->pfn;
+	iqp.vfn		= 0;
+	iqp.iqid	= csio_q_iqid(hw, iq_idx);
+	iqp.type	= FW_IQ_TYPE_FL_INT_CAP;
+
+	flq_idx = csio_q_iq_flq_idx(hw, iq_idx);
+	if (flq_idx != -1)
+		iqp.fl0id = csio_q_flid(hw, flq_idx);
+	else
+		iqp.fl0id = 0xFFFF;
+
+	iqp.fl1id = 0xFFFF;
+
+	csio_mb_iq_free(hw, mbp, priv, CSIO_MB_DEFAULT_TMO, &iqp, cbfn);
+
+	rv = csio_mb_issue(hw, mbp);
+	if (rv != 0) {
+		mempool_free(mbp, hw->mb_mempool);
+		return rv;
+	}
+
+	if (cbfn != NULL)
+		return 0;
+
+	return csio_wr_iq_destroy_rsp(hw, mbp, iq_idx);
+}
+
+/*
+ * csio_wr_eq_destroy_rsp - Response handler for OFLD EQ creation.
+ * @hw: The HW module.
+ * @mbp: Mailbox.
+ * @eq_idx: Egress queue that was freed.
+ *
+ * Handle FW_OFLD_EQ_CMD (free) mailbox completion.
+ */
+static int
+csio_wr_eq_destroy_rsp(struct csio_hw *hw, struct csio_mb *mbp, int eq_idx)
+{
+	enum fw_retval retval = csio_mb_fw_retval(mbp);
+	int rv = 0;
+
+	if (retval != FW_SUCCESS)
+		rv = -EINVAL;
+
+	mempool_free(mbp, hw->mb_mempool);
+
+	return rv;
+}
+
+/*
+ * csio_wr_eq_destroy - Free an Egress queue.
+ * @hw: The HW module.
+ * @priv: Private data object.
+ * @eq_idx: Egress queue index to destroy
+ * @cbfn: Completion callback.
+ *
+ * This API frees an Egress queue by issuing the FW_EQ_OFLD_CMD
+ * with the free bit set.
+ */
+static int
+csio_wr_eq_destroy(struct csio_hw *hw, void *priv, int eq_idx,
+		   void (*cbfn) (struct csio_hw *, struct csio_mb *))
+{
+	int rv = 0;
+	struct csio_mb  *mbp;
+	struct csio_eq_params eqp;
+
+	memset(&eqp, 0, sizeof(struct csio_eq_params));
+
+	mbp = mempool_alloc(hw->mb_mempool, GFP_ATOMIC);
+	if (!mbp)
+		return -ENOMEM;
+
+	eqp.pfn		= hw->pfn;
+	eqp.vfn		= 0;
+	eqp.eqid	= csio_q_eqid(hw, eq_idx);
+
+	csio_mb_eq_ofld_free(hw, mbp, priv, CSIO_MB_DEFAULT_TMO, &eqp, cbfn);
+
+	rv = csio_mb_issue(hw, mbp);
+	if (rv != 0) {
+		mempool_free(mbp, hw->mb_mempool);
+		return rv;
+	}
+
+	if (cbfn != NULL)
+		return 0;
+
+	return csio_wr_eq_destroy_rsp(hw, mbp, eq_idx);
+}
+
+/*
+ * csio_wr_cleanup_eq_stpg - Cleanup Egress queue status page
+ * @hw: HW module
+ * @qidx: Egress queue index
+ *
+ * Cleanup the Egress queue status page.
+ */
+static void
+csio_wr_cleanup_eq_stpg(struct csio_hw *hw, int qidx)
+{
+	struct csio_q	*q = csio_hw_to_wrm(hw)->q_arr[qidx];
+	struct csio_qstatus_page *stp = (struct csio_qstatus_page *)q->vwrap;
+
+	memset(stp, 0, sizeof(*stp));
+}
+
+/*
+ * csio_wr_cleanup_iq_ftr - Cleanup Footer entries in IQ
+ * @hw: HW module
+ * @qidx: Ingress queue index
+ *
+ * Cleanup the footer entries in the given ingress queue,
+ * set to 1 the internal copy of genbit.
+ */
+static void
+csio_wr_cleanup_iq_ftr(struct csio_hw *hw, int qidx)
+{
+	struct csio_wrm *wrm	= csio_hw_to_wrm(hw);
+	struct csio_q	*q	= wrm->q_arr[qidx];
+	void *wr;
+	struct csio_iqwr_footer *ftr;
+	uint32_t i = 0;
+
+	/* set to 1 since we are just about zero out genbit */
+	q->un.iq.genbit = 1;
+
+	for (i = 0; i < q->credits; i++) {
+		/* Get the WR */
+		wr = (void *)((uintptr_t)q->vstart +
+					   (i * q->wr_sz));
+		/* Get the footer */
+		ftr = (struct csio_iqwr_footer *)((uintptr_t)wr +
+					  (q->wr_sz - sizeof(*ftr)));
+		/* Zero out footer */
+		memset(ftr, 0, sizeof(*ftr));
+	}
+}
+
+int
+csio_wr_destroy_queues(struct csio_hw *hw, bool cmd)
+{
+	int i, flq_idx;
+	struct csio_q *q;
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	int rv;
+
+	for (i = 0; i < wrm->free_qidx; i++) {
+		q = wrm->q_arr[i];
+
+		switch (q->type) {
+		case CSIO_EGRESS:
+			if (csio_q_eqid(hw, i) != CSIO_MAX_QID) {
+				csio_wr_cleanup_eq_stpg(hw, i);
+				if (!cmd) {
+					csio_q_eqid(hw, i) = CSIO_MAX_QID;
+					continue;
+				}
+
+				rv = csio_wr_eq_destroy(hw, NULL, i, NULL);
+				if ((rv == -EBUSY) || (rv == -ETIMEDOUT))
+					cmd = false;
+
+				csio_q_eqid(hw, i) = CSIO_MAX_QID;
+			}
+		case CSIO_INGRESS:
+			if (csio_q_iqid(hw, i) != CSIO_MAX_QID) {
+				csio_wr_cleanup_iq_ftr(hw, i);
+				if (!cmd) {
+					csio_q_iqid(hw, i) = CSIO_MAX_QID;
+					flq_idx = csio_q_iq_flq_idx(hw, i);
+					if (flq_idx != -1)
+						csio_q_flid(hw, flq_idx) =
+								CSIO_MAX_QID;
+					continue;
+				}
+
+				rv = csio_wr_iq_destroy(hw, NULL, i, NULL);
+				if ((rv == -EBUSY) || (rv == -ETIMEDOUT))
+					cmd = false;
+
+				csio_q_iqid(hw, i) = CSIO_MAX_QID;
+				flq_idx = csio_q_iq_flq_idx(hw, i);
+				if (flq_idx != -1)
+					csio_q_flid(hw, flq_idx) = CSIO_MAX_QID;
+			}
+		default:
+			break;
+		}
+	}
+
+	hw->flags &= ~CSIO_HWF_Q_FW_ALLOCED;
+
+	return 0;
+}
+
+/*
+ * csio_wr_get - Get requested size of WR entry/entries from queue.
+ * @hw: HW module.
+ * @qidx: Index of queue.
+ * @size: Cumulative size of Work request(s).
+ * @wrp: Work request pair.
+ *
+ * If requested credits are available, return the start address of the
+ * work request in the work request pair. Set pidx accordingly and
+ * return.
+ *
+ * NOTE about WR pair:
+ * ==================
+ * A WR can start towards the end of a queue, and then continue at the
+ * beginning, since the queue is considered to be circular. This will
+ * require a pair of address/size to be passed back to the caller -
+ * hence Work request pair format.
+ */
+int
+csio_wr_get(struct csio_hw *hw, int qidx, uint32_t size,
+	    struct csio_wr_pair *wrp)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_q *q = wrm->q_arr[qidx];
+	void *cwr = (void *)((uintptr_t)(q->vstart) +
+						(q->pidx * CSIO_QCREDIT_SZ));
+	struct csio_qstatus_page *stp = (struct csio_qstatus_page *)q->vwrap;
+	uint16_t cidx = q->cidx = ntohs(stp->cidx);
+	uint16_t pidx = q->pidx;
+	uint32_t req_sz	= ALIGN(size, CSIO_QCREDIT_SZ);
+	int req_credits	= req_sz / CSIO_QCREDIT_SZ;
+	int credits;
+
+	CSIO_DB_ASSERT(q->owner != NULL);
+	CSIO_DB_ASSERT((qidx >= 0) && (qidx < wrm->free_qidx));
+	CSIO_DB_ASSERT(cidx <= q->credits);
+
+	/* Calculate credits */
+	if (pidx > cidx) {
+		credits = q->credits - (pidx - cidx) - 1;
+	} else if (cidx > pidx) {
+		credits = cidx - pidx - 1;
+	} else {
+		/* cidx == pidx, empty queue */
+		credits = q->credits;
+		CSIO_INC_STATS(q, n_qempty);
+	}
+
+	/*
+	 * Check if we have enough credits.
+	 * credits = 1 implies queue is full.
+	 */
+	if (!credits || (req_credits > credits)) {
+		CSIO_INC_STATS(q, n_qfull);
+		return -EBUSY;
+	}
+
+	/*
+	 * If we are here, we have enough credits to satisfy the
+	 * request. Check if we are near the end of q, and if WR spills over.
+	 * If it does, use the first addr/size to cover the queue until
+	 * the end. Fit the remainder portion of the request at the top
+	 * of queue and return it in the second addr/len. Set pidx
+	 * accordingly.
+	 */
+	if (unlikely(((uintptr_t)cwr + req_sz) > (uintptr_t)(q->vwrap))) {
+		wrp->addr1 = cwr;
+		wrp->size1 = (uint32_t)((uintptr_t)q->vwrap - (uintptr_t)cwr);
+		wrp->addr2 = q->vstart;
+		wrp->size2 = req_sz - wrp->size1;
+		q->pidx	= (uint16_t)(ALIGN(wrp->size2, CSIO_QCREDIT_SZ) /
+							CSIO_QCREDIT_SZ);
+		CSIO_INC_STATS(q, n_qwrap);
+		CSIO_INC_STATS(q, n_eq_wr_split);
+	} else {
+		wrp->addr1 = cwr;
+		wrp->size1 = req_sz;
+		wrp->addr2 = NULL;
+		wrp->size2 = 0;
+		q->pidx	+= (uint16_t)req_credits;
+
+		/* We are the end of queue, roll back pidx to top of queue */
+		if (unlikely(q->pidx == q->credits)) {
+			q->pidx = 0;
+			CSIO_INC_STATS(q, n_qwrap);
+		}
+	}
+
+	q->inc_idx = (uint16_t)req_credits;
+
+	CSIO_INC_STATS(q, n_tot_reqs);
+
+	return 0;
+}
+
+/*
+ * csio_wr_copy_to_wrp - Copies given data into WR.
+ * @data_buf - Data buffer
+ * @wrp - Work request pair.
+ * @wr_off - Work request offset.
+ * @data_len - Data length.
+ *
+ * Copies the given data in Work Request. Work request pair(wrp) specifies
+ * address information of Work request.
+ * Returns: none
+ */
+void
+csio_wr_copy_to_wrp(void *data_buf, struct csio_wr_pair *wrp,
+		   uint32_t wr_off, uint32_t data_len)
+{
+	uint32_t nbytes;
+
+	/* Number of space available in buffer addr1 of WRP */
+	nbytes = ((wrp->size1 - wr_off) >= data_len) ?
+					data_len : (wrp->size1 - wr_off);
+
+	memcpy((uint8_t *) wrp->addr1 + wr_off, data_buf, nbytes);
+	data_len -= nbytes;
+
+	/* Write the remaining data from the begining of circular buffer */
+	if (data_len) {
+		CSIO_DB_ASSERT(data_len <= wrp->size2);
+		CSIO_DB_ASSERT(wrp->addr2 != NULL);
+		memcpy(wrp->addr2, (uint8_t *) data_buf + nbytes, data_len);
+	}
+}
+
+/*
+ * csio_wr_issue - Notify chip of Work request.
+ * @hw: HW module.
+ * @qidx: Index of queue.
+ * @prio: 0: Low priority, 1: High priority
+ *
+ * Rings the SGE Doorbell by writing the current producer index of the passed
+ * in queue into the register.
+ *
+ */
+int
+csio_wr_issue(struct csio_hw *hw, int qidx, bool prio)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_q *q = wrm->q_arr[qidx];
+
+	CSIO_DB_ASSERT((qidx >= 0) && (qidx < wrm->free_qidx));
+
+	wmb();
+	/* Ring SGE Doorbell writing q->pidx into it */
+	csio_wr_reg32(hw, DBPRIO(prio) | QID(q->un.eq.physeqid) |
+		      PIDX(q->inc_idx), MYPF_REG(SGE_PF_KDOORBELL));
+	q->inc_idx = 0;
+
+	return 0;
+}
+
+static inline uint32_t
+csio_wr_avail_qcredits(struct csio_q *q)
+{
+	if (q->pidx > q->cidx)
+		return q->pidx - q->cidx;
+	else if (q->cidx > q->pidx)
+		return q->credits - (q->cidx - q->pidx);
+	else
+		return 0;	/* cidx == pidx, empty queue */
+}
+
+/*
+ * csio_wr_inval_flq_buf - Invalidate a free list buffer entry.
+ * @hw: HW module.
+ * @flq: The freelist queue.
+ *
+ * Invalidate the driver's version of a freelist buffer entry,
+ * without freeing the associated the DMA memory. The entry
+ * to be invalidated is picked up from the current Free list
+ * queue cidx.
+ *
+ */
+static inline void
+csio_wr_inval_flq_buf(struct csio_hw *hw, struct csio_q *flq)
+{
+	flq->cidx++;
+	if (flq->cidx == flq->credits) {
+		flq->cidx = 0;
+		CSIO_INC_STATS(flq, n_qwrap);
+	}
+}
+
+/*
+ * csio_wr_process_fl - Process a freelist completion.
+ * @hw: HW module.
+ * @q: The ingress queue attached to the Freelist.
+ * @wr: The freelist completion WR in the ingress queue.
+ * @len_to_qid: The lower 32-bits of the first flit of the RSP footer
+ * @iq_handler: Caller's handler for this completion.
+ * @priv: Private pointer of caller
+ *
+ */
+static inline void
+csio_wr_process_fl(struct csio_hw *hw, struct csio_q *q,
+		   void *wr, uint32_t len_to_qid,
+		   void (*iq_handler)(struct csio_hw *, void *,
+				      uint32_t, struct csio_fl_dma_buf *,
+				      void *),
+		   void *priv)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_sge *sge = &wrm->sge;
+	struct csio_fl_dma_buf flb;
+	struct csio_dma_buf *buf, *fbuf;
+	uint32_t bufsz, len, lastlen = 0;
+	int n;
+	struct csio_q *flq = hw->wrm.q_arr[q->un.iq.flq_idx];
+
+	CSIO_DB_ASSERT(flq != NULL);
+
+	len = len_to_qid;
+
+	if (len & IQWRF_NEWBUF) {
+		if (flq->un.fl.offset > 0) {
+			csio_wr_inval_flq_buf(hw, flq);
+			flq->un.fl.offset = 0;
+		}
+		len = IQWRF_LEN_GET(len);
+	}
+
+	CSIO_DB_ASSERT(len != 0);
+
+	flb.totlen = len;
+
+	/* Consume all freelist buffers used for len bytes */
+	for (n = 0, fbuf = flb.flbufs; ; n++, fbuf++) {
+		buf = &flq->un.fl.bufs[flq->cidx];
+		bufsz = csio_wr_fl_bufsz(sge, buf);
+
+		fbuf->paddr	= buf->paddr;
+		fbuf->vaddr	= buf->vaddr;
+
+		flb.offset	= flq->un.fl.offset;
+		lastlen		= min(bufsz, len);
+		fbuf->len	= lastlen;
+
+		len -= lastlen;
+		if (!len)
+			break;
+		csio_wr_inval_flq_buf(hw, flq);
+	}
+
+	flb.defer_free = flq->un.fl.packen ? 0 : 1;
+
+	iq_handler(hw, wr, q->wr_sz - sizeof(struct csio_iqwr_footer),
+		   &flb, priv);
+
+	if (flq->un.fl.packen)
+		flq->un.fl.offset += ALIGN(lastlen, sge->csio_fl_align);
+	else
+		csio_wr_inval_flq_buf(hw, flq);
+
+}
+
+/*
+ * csio_is_new_iqwr - Is this a new Ingress queue entry ?
+ * @q: Ingress quueue.
+ * @ftr: Ingress queue WR SGE footer.
+ *
+ * The entry is new if our generation bit matches the corresponding
+ * bit in the footer of the current WR.
+ */
+static inline bool
+csio_is_new_iqwr(struct csio_q *q, struct csio_iqwr_footer *ftr)
+{
+	return (q->un.iq.genbit == (ftr->u.type_gen >> IQWRF_GEN_SHIFT));
+}
+
+/*
+ * csio_wr_process_iq - Process elements in Ingress queue.
+ * @hw:  HW pointer
+ * @qidx: Index of queue
+ * @iq_handler: Handler for this queue
+ * @priv: Caller's private pointer
+ *
+ * This routine walks through every entry of the ingress queue, calling
+ * the provided iq_handler with the entry, until the generation bit
+ * flips.
+ */
+int
+csio_wr_process_iq(struct csio_hw *hw, struct csio_q *q,
+		   void (*iq_handler)(struct csio_hw *, void *,
+				      uint32_t, struct csio_fl_dma_buf *,
+				      void *),
+		   void *priv)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	void *wr = (void *)((uintptr_t)q->vstart + (q->cidx * q->wr_sz));
+	struct csio_iqwr_footer *ftr;
+	uint32_t wr_type, fw_qid, qid;
+	struct csio_q *q_completed;
+	struct csio_q *flq = csio_iq_has_fl(q) ?
+					wrm->q_arr[q->un.iq.flq_idx] : NULL;
+	int rv = 0;
+
+	/* Get the footer */
+	ftr = (struct csio_iqwr_footer *)((uintptr_t)wr +
+					  (q->wr_sz - sizeof(*ftr)));
+
+	/*
+	 * When q wrapped around last time, driver should have inverted
+	 * ic.genbit as well.
+	 */
+	while (csio_is_new_iqwr(q, ftr)) {
+
+		CSIO_DB_ASSERT(((uintptr_t)wr + q->wr_sz) <=
+						(uintptr_t)q->vwrap);
+		rmb();
+		wr_type = IQWRF_TYPE_GET(ftr->u.type_gen);
+
+		switch (wr_type) {
+		case X_RSPD_TYPE_CPL:
+			/* Subtract footer from WR len */
+			iq_handler(hw, wr, q->wr_sz - sizeof(*ftr), NULL, priv);
+			break;
+		case X_RSPD_TYPE_FLBUF:
+			csio_wr_process_fl(hw, q, wr,
+					   ntohl(ftr->pldbuflen_qid),
+					   iq_handler, priv);
+			break;
+		case X_RSPD_TYPE_INTR:
+			fw_qid = ntohl(ftr->pldbuflen_qid);
+			qid = fw_qid - wrm->fw_iq_start;
+			q_completed = hw->wrm.intr_map[qid];
+
+			if (unlikely(qid ==
+					csio_q_physiqid(hw, hw->intr_iq_idx))) {
+				/*
+				 * We are already in the Forward Interrupt
+				 * Interrupt Queue Service! Do-not service
+				 * again!
+				 *
+				 */
+			} else {
+				CSIO_DB_ASSERT(q_completed);
+				CSIO_DB_ASSERT(
+					q_completed->un.iq.iq_intx_handler);
+
+				/* Call the queue handler. */
+				q_completed->un.iq.iq_intx_handler(hw, NULL,
+						0, NULL, (void *)q_completed);
+			}
+			break;
+		default:
+			csio_warn(hw, "Unknown resp type 0x%x received\n",
+				 wr_type);
+			CSIO_INC_STATS(q, n_rsp_unknown);
+			break;
+		}
+
+		/*
+		 * Ingress *always* has fixed size WR entries. Therefore,
+		 * there should always be complete WRs towards the end of
+		 * queue.
+		 */
+		if (((uintptr_t)wr + q->wr_sz) == (uintptr_t)q->vwrap) {
+
+			/* Roll over to start of queue */
+			q->cidx = 0;
+			wr	= q->vstart;
+
+			/* Toggle genbit */
+			q->un.iq.genbit ^= 0x1;
+
+			CSIO_INC_STATS(q, n_qwrap);
+		} else {
+			q->cidx++;
+			wr	= (void *)((uintptr_t)(q->vstart) +
+					   (q->cidx * q->wr_sz));
+		}
+
+		ftr = (struct csio_iqwr_footer *)((uintptr_t)wr +
+						  (q->wr_sz - sizeof(*ftr)));
+		q->inc_idx++;
+
+	} /* while (q->un.iq.genbit == hdr->genbit) */
+
+	/*
+	 * We need to re-arm SGE interrupts in case we got a stray interrupt,
+	 * especially in msix mode. With INTx, this may be a common occurence.
+	 */
+	if (unlikely(!q->inc_idx)) {
+		CSIO_INC_STATS(q, n_stray_comp);
+		rv = -EINVAL;
+		goto restart;
+	}
+
+	/* Replenish free list buffers if pending falls below low water mark */
+	if (flq) {
+		uint32_t avail  = csio_wr_avail_qcredits(flq);
+		if (avail <= 16) {
+			/* Make sure in FLQ, atleast 1 credit (8 FL buffers)
+			 * remains unpopulated otherwise HW thinks
+			 * FLQ is empty.
+			 */
+			csio_wr_update_fl(hw, flq, (flq->credits - 8) - avail);
+			csio_wr_ring_fldb(hw, flq);
+		}
+	}
+
+restart:
+	/* Now inform SGE about our incremental index value */
+	csio_wr_reg32(hw, CIDXINC(q->inc_idx)		|
+			  INGRESSQID(q->un.iq.physiqid)	|
+			  TIMERREG(csio_sge_timer_reg),
+			  MYPF_REG(SGE_PF_GTS));
+	q->stats.n_tot_rsps += q->inc_idx;
+
+	q->inc_idx = 0;
+
+	return rv;
+}
+
+int
+csio_wr_process_iq_idx(struct csio_hw *hw, int qidx,
+		   void (*iq_handler)(struct csio_hw *, void *,
+				      uint32_t, struct csio_fl_dma_buf *,
+				      void *),
+		   void *priv)
+{
+	struct csio_wrm *wrm	= csio_hw_to_wrm(hw);
+	struct csio_q	*iq	= wrm->q_arr[qidx];
+
+	return csio_wr_process_iq(hw, iq, iq_handler, priv);
+}
+
+static int
+csio_closest_timer(struct csio_sge *s, int time)
+{
+	int i, delta, match = 0, min_delta = INT_MAX;
+
+	for (i = 0; i < ARRAY_SIZE(s->timer_val); i++) {
+		delta = time - s->timer_val[i];
+		if (delta < 0)
+			delta = -delta;
+		if (delta < min_delta) {
+			min_delta = delta;
+			match = i;
+		}
+	}
+	return match;
+}
+
+static int
+csio_closest_thresh(struct csio_sge *s, int cnt)
+{
+	int i, delta, match = 0, min_delta = INT_MAX;
+
+	for (i = 0; i < ARRAY_SIZE(s->counter_val); i++) {
+		delta = cnt - s->counter_val[i];
+		if (delta < 0)
+			delta = -delta;
+		if (delta < min_delta) {
+			min_delta = delta;
+			match = i;
+		}
+	}
+	return match;
+}
+
+static void
+csio_wr_fixup_host_params(struct csio_hw *hw)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_sge *sge = &wrm->sge;
+	uint32_t clsz = L1_CACHE_BYTES;
+	uint32_t s_hps = PAGE_SHIFT - 10;
+	uint32_t ingpad = 0;
+	uint32_t stat_len = clsz > 64 ? 128 : 64;
+
+	csio_wr_reg32(hw, HOSTPAGESIZEPF0(s_hps) | HOSTPAGESIZEPF1(s_hps) |
+		      HOSTPAGESIZEPF2(s_hps) | HOSTPAGESIZEPF3(s_hps) |
+		      HOSTPAGESIZEPF4(s_hps) | HOSTPAGESIZEPF5(s_hps) |
+		      HOSTPAGESIZEPF6(s_hps) | HOSTPAGESIZEPF7(s_hps),
+		      SGE_HOST_PAGE_SIZE);
+
+	sge->csio_fl_align = clsz < 32 ? 32 : clsz;
+	ingpad = ilog2(sge->csio_fl_align) - 5;
+
+	csio_set_reg_field(hw, SGE_CONTROL, INGPADBOUNDARY_MASK |
+					    EGRSTATUSPAGESIZE(1),
+			   INGPADBOUNDARY(ingpad) |
+			   EGRSTATUSPAGESIZE(stat_len != 64));
+
+	/* FL BUFFER SIZE#0 is Page size i,e already aligned to cache line */
+	csio_wr_reg32(hw, PAGE_SIZE, SGE_FL_BUFFER_SIZE0);
+	csio_wr_reg32(hw,
+		      (csio_rd_reg32(hw, SGE_FL_BUFFER_SIZE2) +
+		      sge->csio_fl_align - 1) & ~(sge->csio_fl_align - 1),
+		      SGE_FL_BUFFER_SIZE2);
+	csio_wr_reg32(hw,
+		      (csio_rd_reg32(hw, SGE_FL_BUFFER_SIZE3) +
+		      sge->csio_fl_align - 1) & ~(sge->csio_fl_align - 1),
+		      SGE_FL_BUFFER_SIZE3);
+
+	csio_wr_reg32(hw, HPZ0(PAGE_SHIFT - 12), ULP_RX_TDDP_PSZ);
+
+	/* default value of rx_dma_offset of the NIC driver */
+	csio_set_reg_field(hw, SGE_CONTROL, PKTSHIFT_MASK,
+			   PKTSHIFT(CSIO_SGE_RX_DMA_OFFSET));
+}
+
+static void
+csio_init_intr_coalesce_parms(struct csio_hw *hw)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_sge *sge = &wrm->sge;
+
+	csio_sge_thresh_reg = csio_closest_thresh(sge, csio_intr_coalesce_cnt);
+	if (csio_intr_coalesce_cnt) {
+		csio_sge_thresh_reg = 0;
+		csio_sge_timer_reg = X_TIMERREG_RESTART_COUNTER;
+		return;
+	}
+
+	csio_sge_timer_reg = csio_closest_timer(sge, csio_intr_coalesce_time);
+}
+
+/*
+ * csio_wr_get_sge - Get SGE register values.
+ * @hw: HW module.
+ *
+ * Used by non-master functions and by master-functions relying on config file.
+ */
+static void
+csio_wr_get_sge(struct csio_hw *hw)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_sge *sge = &wrm->sge;
+	uint32_t ingpad;
+	int i;
+	u32 timer_value_0_and_1, timer_value_2_and_3, timer_value_4_and_5;
+	u32 ingress_rx_threshold;
+
+	sge->sge_control = csio_rd_reg32(hw, SGE_CONTROL);
+
+	ingpad = INGPADBOUNDARY_GET(sge->sge_control);
+
+	switch (ingpad) {
+	case X_INGPCIEBOUNDARY_32B:
+		sge->csio_fl_align = 32; break;
+	case X_INGPCIEBOUNDARY_64B:
+		sge->csio_fl_align = 64; break;
+	case X_INGPCIEBOUNDARY_128B:
+		sge->csio_fl_align = 128; break;
+	case X_INGPCIEBOUNDARY_256B:
+		sge->csio_fl_align = 256; break;
+	case X_INGPCIEBOUNDARY_512B:
+		sge->csio_fl_align = 512; break;
+	case X_INGPCIEBOUNDARY_1024B:
+		sge->csio_fl_align = 1024; break;
+	case X_INGPCIEBOUNDARY_2048B:
+		sge->csio_fl_align = 2048; break;
+	case X_INGPCIEBOUNDARY_4096B:
+		sge->csio_fl_align = 4096; break;
+	}
+
+	for (i = 0; i < CSIO_SGE_FL_SIZE_REGS; i++)
+		csio_get_flbuf_size(hw, sge, i);
+
+	timer_value_0_and_1 = csio_rd_reg32(hw, SGE_TIMER_VALUE_0_AND_1);
+	timer_value_2_and_3 = csio_rd_reg32(hw, SGE_TIMER_VALUE_2_AND_3);
+	timer_value_4_and_5 = csio_rd_reg32(hw, SGE_TIMER_VALUE_4_AND_5);
+
+	sge->timer_val[0] = (uint16_t)csio_core_ticks_to_us(hw,
+					TIMERVALUE0_GET(timer_value_0_and_1));
+	sge->timer_val[1] = (uint16_t)csio_core_ticks_to_us(hw,
+					TIMERVALUE1_GET(timer_value_0_and_1));
+	sge->timer_val[2] = (uint16_t)csio_core_ticks_to_us(hw,
+					TIMERVALUE2_GET(timer_value_2_and_3));
+	sge->timer_val[3] = (uint16_t)csio_core_ticks_to_us(hw,
+					TIMERVALUE3_GET(timer_value_2_and_3));
+	sge->timer_val[4] = (uint16_t)csio_core_ticks_to_us(hw,
+					TIMERVALUE4_GET(timer_value_4_and_5));
+	sge->timer_val[5] = (uint16_t)csio_core_ticks_to_us(hw,
+					TIMERVALUE5_GET(timer_value_4_and_5));
+
+	ingress_rx_threshold = csio_rd_reg32(hw, SGE_INGRESS_RX_THRESHOLD);
+	sge->counter_val[0] = THRESHOLD_0_GET(ingress_rx_threshold);
+	sge->counter_val[1] = THRESHOLD_1_GET(ingress_rx_threshold);
+	sge->counter_val[2] = THRESHOLD_2_GET(ingress_rx_threshold);
+	sge->counter_val[3] = THRESHOLD_3_GET(ingress_rx_threshold);
+
+	csio_init_intr_coalesce_parms(hw);
+}
+
+/*
+ * csio_wr_set_sge - Initialize SGE registers
+ * @hw: HW module.
+ *
+ * Used by Master function to initialize SGE registers in the absence
+ * of a config file.
+ */
+static void
+csio_wr_set_sge(struct csio_hw *hw)
+{
+	struct csio_wrm *wrm = csio_hw_to_wrm(hw);
+	struct csio_sge *sge = &wrm->sge;
+	int i;
+
+	/*
+	 * Set up our basic SGE mode to deliver CPL messages to our Ingress
+	 * Queue and Packet Date to the Free List.
+	 */
+	csio_set_reg_field(hw, SGE_CONTROL, RXPKTCPLMODE(1), RXPKTCPLMODE(1));
+
+	sge->sge_control = csio_rd_reg32(hw, SGE_CONTROL);
+
+	/* sge->csio_fl_align is set up by csio_wr_fixup_host_params(). */
+
+	/*
+	 * Set up to drop DOORBELL writes when the DOORBELL FIFO overflows
+	 * and generate an interrupt when this occurs so we can recover.
+	 */
+	csio_set_reg_field(hw, SGE_DBFIFO_STATUS,
+			   HP_INT_THRESH(HP_INT_THRESH_MASK) |
+			   LP_INT_THRESH(LP_INT_THRESH_MASK),
+			   HP_INT_THRESH(CSIO_SGE_DBFIFO_INT_THRESH) |
+			   LP_INT_THRESH(CSIO_SGE_DBFIFO_INT_THRESH));
+	csio_set_reg_field(hw, SGE_DOORBELL_CONTROL, ENABLE_DROP,
+			   ENABLE_DROP);
+
+	/* SGE_FL_BUFFER_SIZE0 is set up by csio_wr_fixup_host_params(). */
+
+	CSIO_SET_FLBUF_SIZE(hw, 1, CSIO_SGE_FLBUF_SIZE1);
+	CSIO_SET_FLBUF_SIZE(hw, 2, CSIO_SGE_FLBUF_SIZE2);
+	CSIO_SET_FLBUF_SIZE(hw, 3, CSIO_SGE_FLBUF_SIZE3);
+	CSIO_SET_FLBUF_SIZE(hw, 4, CSIO_SGE_FLBUF_SIZE4);
+	CSIO_SET_FLBUF_SIZE(hw, 5, CSIO_SGE_FLBUF_SIZE5);
+	CSIO_SET_FLBUF_SIZE(hw, 6, CSIO_SGE_FLBUF_SIZE6);
+	CSIO_SET_FLBUF_SIZE(hw, 7, CSIO_SGE_FLBUF_SIZE7);
+	CSIO_SET_FLBUF_SIZE(hw, 8, CSIO_SGE_FLBUF_SIZE8);
+
+	for (i = 0; i < CSIO_SGE_FL_SIZE_REGS; i++)
+		csio_get_flbuf_size(hw, sge, i);
+
+	/* Initialize interrupt coalescing attributes */
+	sge->timer_val[0] = CSIO_SGE_TIMER_VAL_0;
+	sge->timer_val[1] = CSIO_SGE_TIMER_VAL_1;
+	sge->timer_val[2] = CSIO_SGE_TIMER_VAL_2;
+	sge->timer_val[3] = CSIO_SGE_TIMER_VAL_3;
+	sge->timer_val[4] = CSIO_SGE_TIMER_VAL_4;
+	sge->timer_val[5] = CSIO_SGE_TIMER_VAL_5;
+
+	sge->counter_val[0] = CSIO_SGE_INT_CNT_VAL_0;
+	sge->counter_val[1] = CSIO_SGE_INT_CNT_VAL_1;
+	sge->counter_val[2] = CSIO_SGE_INT_CNT_VAL_2;
+	sge->counter_val[3] = CSIO_SGE_INT_CNT_VAL_3;
+
+	csio_wr_reg32(hw, THRESHOLD_0(sge->counter_val[0]) |
+		      THRESHOLD_1(sge->counter_val[1]) |
+		      THRESHOLD_2(sge->counter_val[2]) |
+		      THRESHOLD_3(sge->counter_val[3]),
+		      SGE_INGRESS_RX_THRESHOLD);
+
+	csio_wr_reg32(hw,
+		   TIMERVALUE0(csio_us_to_core_ticks(hw, sge->timer_val[0])) |
+		   TIMERVALUE1(csio_us_to_core_ticks(hw, sge->timer_val[1])),
+		   SGE_TIMER_VALUE_0_AND_1);
+
+	csio_wr_reg32(hw,
+		   TIMERVALUE2(csio_us_to_core_ticks(hw, sge->timer_val[2])) |
+		   TIMERVALUE3(csio_us_to_core_ticks(hw, sge->timer_val[3])),
+		   SGE_TIMER_VALUE_2_AND_3);
+
+	csio_wr_reg32(hw,
+		   TIMERVALUE4(csio_us_to_core_ticks(hw, sge->timer_val[4])) |
+		   TIMERVALUE5(csio_us_to_core_ticks(hw, sge->timer_val[5])),
+		   SGE_TIMER_VALUE_4_AND_5);
+
+	csio_init_intr_coalesce_parms(hw);
+}
+
+void
+csio_wr_sge_init(struct csio_hw *hw)
+{
+	/*
+	 * If we are master:
+	 *    - If we plan to use the config file, we need to fixup some
+	 *      host specific registers, and read the rest of the SGE
+	 *      configuration.
+	 *    - If we dont plan to use the config file, we need to initialize
+	 *      SGE entirely, including fixing the host specific registers.
+	 * If we arent the master, we are only allowed to read and work off of
+	 *      the already initialized SGE values.
+	 *
+	 * Therefore, before calling this function, we assume that the master-
+	 * ship of the card, and whether to use config file or not, have
+	 * already been decided. In other words, CSIO_HWF_USING_SOFT_PARAMS and
+	 * CSIO_HWF_MASTER should be set/unset.
+	 */
+	if (csio_is_hw_master(hw)) {
+		csio_wr_fixup_host_params(hw);
+
+		if (hw->flags & CSIO_HWF_USING_SOFT_PARAMS)
+			csio_wr_get_sge(hw);
+		else
+			csio_wr_set_sge(hw);
+	} else
+		csio_wr_get_sge(hw);
+}
+
+/*
+ * csio_wrm_init - Initialize Work request module.
+ * @wrm: WR module
+ * @hw: HW pointer
+ *
+ * Allocates memory for an array of queue pointers starting at q_arr.
+ */
+int
+csio_wrm_init(struct csio_wrm *wrm, struct csio_hw *hw)
+{
+	int i;
+
+	if (!wrm->num_q) {
+		csio_err(hw, "Num queues is not set\n");
+		return -EINVAL;
+	}
+
+	wrm->q_arr = kzalloc(sizeof(struct csio_q *) * wrm->num_q, GFP_KERNEL);
+	if (!wrm->q_arr)
+		goto err;
+
+	for (i = 0; i < wrm->num_q; i++) {
+		wrm->q_arr[i] = kzalloc(sizeof(struct csio_q), GFP_KERNEL);
+		if (!wrm->q_arr[i]) {
+			while (--i >= 0)
+				kfree(wrm->q_arr[i]);
+			goto err_free_arr;
+		}
+	}
+	wrm->free_qidx	= 0;
+
+	return 0;
+
+err_free_arr:
+	kfree(wrm->q_arr);
+err:
+	return -ENOMEM;
+}
+
+/*
+ * csio_wrm_exit - Initialize Work request module.
+ * @wrm: WR module
+ * @hw: HW module
+ *
+ * Uninitialize WR module. Free q_arr and pointers in it.
+ * We have the additional job of freeing the DMA memory associated
+ * with the queues.
+ */
+void
+csio_wrm_exit(struct csio_wrm *wrm, struct csio_hw *hw)
+{
+	int i;
+	uint32_t j;
+	struct csio_q *q;
+	struct csio_dma_buf *buf;
+
+	for (i = 0; i < wrm->num_q; i++) {
+		q = wrm->q_arr[i];
+
+		if (wrm->free_qidx && (i < wrm->free_qidx)) {
+			if (q->type == CSIO_FREELIST) {
+				if (!q->un.fl.bufs)
+					continue;
+				for (j = 0; j < q->credits; j++) {
+					buf = &q->un.fl.bufs[j];
+					if (!buf->vaddr)
+						continue;
+					pci_free_consistent(hw->pdev, buf->len,
+							    buf->vaddr,
+							    buf->paddr);
+				}
+				kfree(q->un.fl.bufs);
+			}
+			pci_free_consistent(hw->pdev, q->size,
+					    q->vstart, q->pstart);
+		}
+		kfree(q);
+	}
+
+	hw->flags &= ~CSIO_HWF_Q_MEM_ALLOCED;
+
+	kfree(wrm->q_arr);
+}