/*
 * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
 * Copyright (c) 2005 Mellanox Technologies. 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/errno.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/slab.h>

#include "mthca_dev.h"
#include "mthca_cmd.h"
#include "mthca_config_reg.h"

enum {
        MTHCA_NUM_ASYNC_EQE = 0x80,
        MTHCA_NUM_CMD_EQE   = 0x80,
        MTHCA_NUM_SPARE_EQE = 0x80,
        MTHCA_EQ_ENTRY_SIZE = 0x20
};

/*
 * Must be packed because start is 64 bits but only aligned to 32 bits.
 */
struct mthca_eq_context {
        __be32 flags;
        __be64 start;
        __be32 logsize_usrpage;
        __be32 tavor_pd;        /* reserved for Arbel */
        u8     reserved1[3];
        u8     intr;
        __be32 arbel_pd;        /* lost_count for Tavor */
        __be32 lkey;
        u32    reserved2[2];
        __be32 consumer_index;
        __be32 producer_index;
        u32    reserved3[4];
} __attribute__((packed));

#define MTHCA_EQ_STATUS_OK          ( 0 << 28)
#define MTHCA_EQ_STATUS_OVERFLOW    ( 9 << 28)
#define MTHCA_EQ_STATUS_WRITE_FAIL  (10 << 28)
#define MTHCA_EQ_OWNER_SW           ( 0 << 24)
#define MTHCA_EQ_OWNER_HW           ( 1 << 24)
#define MTHCA_EQ_FLAG_TR            ( 1 << 18)
#define MTHCA_EQ_FLAG_OI            ( 1 << 17)
#define MTHCA_EQ_STATE_ARMED        ( 1 <<  8)
#define MTHCA_EQ_STATE_FIRED        ( 2 <<  8)
#define MTHCA_EQ_STATE_ALWAYS_ARMED ( 3 <<  8)
#define MTHCA_EQ_STATE_ARBEL        ( 8 <<  8)

enum {
        MTHCA_EVENT_TYPE_COMP               = 0x00,
        MTHCA_EVENT_TYPE_PATH_MIG           = 0x01,
        MTHCA_EVENT_TYPE_COMM_EST           = 0x02,
        MTHCA_EVENT_TYPE_SQ_DRAINED         = 0x03,
        MTHCA_EVENT_TYPE_SRQ_QP_LAST_WQE    = 0x13,
        MTHCA_EVENT_TYPE_SRQ_LIMIT          = 0x14,
        MTHCA_EVENT_TYPE_CQ_ERROR           = 0x04,
        MTHCA_EVENT_TYPE_WQ_CATAS_ERROR     = 0x05,
        MTHCA_EVENT_TYPE_EEC_CATAS_ERROR    = 0x06,
        MTHCA_EVENT_TYPE_PATH_MIG_FAILED    = 0x07,
        MTHCA_EVENT_TYPE_WQ_INVAL_REQ_ERROR = 0x10,
        MTHCA_EVENT_TYPE_WQ_ACCESS_ERROR    = 0x11,
        MTHCA_EVENT_TYPE_SRQ_CATAS_ERROR    = 0x12,
        MTHCA_EVENT_TYPE_LOCAL_CATAS_ERROR  = 0x08,
        MTHCA_EVENT_TYPE_PORT_CHANGE        = 0x09,
        MTHCA_EVENT_TYPE_EQ_OVERFLOW        = 0x0f,
        MTHCA_EVENT_TYPE_ECC_DETECT         = 0x0e,
        MTHCA_EVENT_TYPE_CMD                = 0x0a
};

#define MTHCA_ASYNC_EVENT_MASK ((1ULL << MTHCA_EVENT_TYPE_PATH_MIG)           | \
                                (1ULL << MTHCA_EVENT_TYPE_COMM_EST)           | \
                                (1ULL << MTHCA_EVENT_TYPE_SQ_DRAINED)         | \
                                (1ULL << MTHCA_EVENT_TYPE_CQ_ERROR)           | \
                                (1ULL << MTHCA_EVENT_TYPE_WQ_CATAS_ERROR)     | \
                                (1ULL << MTHCA_EVENT_TYPE_EEC_CATAS_ERROR)    | \
                                (1ULL << MTHCA_EVENT_TYPE_PATH_MIG_FAILED)    | \
                                (1ULL << MTHCA_EVENT_TYPE_WQ_INVAL_REQ_ERROR) | \
                                (1ULL << MTHCA_EVENT_TYPE_WQ_ACCESS_ERROR)    | \
                                (1ULL << MTHCA_EVENT_TYPE_LOCAL_CATAS_ERROR)  | \
                                (1ULL << MTHCA_EVENT_TYPE_PORT_CHANGE)        | \
                                (1ULL << MTHCA_EVENT_TYPE_ECC_DETECT))
#define MTHCA_SRQ_EVENT_MASK   ((1ULL << MTHCA_EVENT_TYPE_SRQ_CATAS_ERROR)    | \
                                (1ULL << MTHCA_EVENT_TYPE_SRQ_QP_LAST_WQE)    | \
                                (1ULL << MTHCA_EVENT_TYPE_SRQ_LIMIT))
#define MTHCA_CMD_EVENT_MASK    (1ULL << MTHCA_EVENT_TYPE_CMD)

#define MTHCA_EQ_DB_INC_CI     (1 << 24)
#define MTHCA_EQ_DB_REQ_NOT    (2 << 24)
#define MTHCA_EQ_DB_DISARM_CQ  (3 << 24)
#define MTHCA_EQ_DB_SET_CI     (4 << 24)
#define MTHCA_EQ_DB_ALWAYS_ARM (5 << 24)

struct mthca_eqe {
        u8 reserved1;
        u8 type;
        u8 reserved2;
        u8 subtype;
        union {
                u32 raw[6];
                struct {
                        __be32 cqn;
                } __attribute__((packed)) comp;
                struct {
                        u16    reserved1;
                        __be16 token;
                        u32    reserved2;
                        u8     reserved3[3];
                        u8     status;
                        __be64 out_param;
                } __attribute__((packed)) cmd;
                struct {
                        __be32 qpn;
                } __attribute__((packed)) qp;
                struct {
                        __be32 srqn;
                } __attribute__((packed)) srq;
                struct {
                        __be32 cqn;
                        u32    reserved1;
                        u8     reserved2[3];
                        u8     syndrome;
                } __attribute__((packed)) cq_err;
                struct {
                        u32    reserved1[2];
                        __be32 port;
                } __attribute__((packed)) port_change;
        } event;
        u8 reserved3[3];
        u8 owner;
} __attribute__((packed));

#define  MTHCA_EQ_ENTRY_OWNER_SW      (0 << 7)
#define  MTHCA_EQ_ENTRY_OWNER_HW      (1 << 7)

static inline u64 async_mask(struct mthca_dev *dev)
{
        return dev->mthca_flags & MTHCA_FLAG_SRQ ?
                MTHCA_ASYNC_EVENT_MASK | MTHCA_SRQ_EVENT_MASK :
                MTHCA_ASYNC_EVENT_MASK;
}

static inline void tavor_set_eq_ci(struct mthca_dev *dev, struct mthca_eq *eq, u32 ci)
{
        /*
         * This barrier makes sure that all updates to ownership bits
         * done by set_eqe_hw() hit memory before the consumer index
         * is updated.  set_eq_ci() allows the HCA to possibly write
         * more EQ entries, and we want to avoid the exceedingly
         * unlikely possibility of the HCA writing an entry and then
         * having set_eqe_hw() overwrite the owner field.
         */
        wmb();
        mthca_write64(MTHCA_EQ_DB_SET_CI | eq->eqn, ci & (eq->nent - 1),
                      dev->kar + MTHCA_EQ_DOORBELL,
                      MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
}

static inline void arbel_set_eq_ci(struct mthca_dev *dev, struct mthca_eq *eq, u32 ci)
{
        /* See comment in tavor_set_eq_ci() above. */
        wmb();
        __raw_writel((__force u32) cpu_to_be32(ci),
                     dev->eq_regs.arbel.eq_set_ci_base + eq->eqn * 8);
        /* We still want ordering, just not swabbing, so add a barrier */
        mb();
}

static inline void set_eq_ci(struct mthca_dev *dev, struct mthca_eq *eq, u32 ci)
{
        if (mthca_is_memfree(dev))
                arbel_set_eq_ci(dev, eq, ci);
        else
                tavor_set_eq_ci(dev, eq, ci);
}

static inline void tavor_eq_req_not(struct mthca_dev *dev, int eqn)
{
        mthca_write64(MTHCA_EQ_DB_REQ_NOT | eqn, 0,
                      dev->kar + MTHCA_EQ_DOORBELL,
                      MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
}

static inline void arbel_eq_req_not(struct mthca_dev *dev, u32 eqn_mask)
{
        writel(eqn_mask, dev->eq_regs.arbel.eq_arm);
}

static inline void disarm_cq(struct mthca_dev *dev, int eqn, int cqn)
{
        if (!mthca_is_memfree(dev)) {
                mthca_write64(MTHCA_EQ_DB_DISARM_CQ | eqn, cqn,
                              dev->kar + MTHCA_EQ_DOORBELL,
                              MTHCA_GET_DOORBELL_LOCK(&dev->doorbell_lock));
        }
}

static inline struct mthca_eqe *get_eqe(struct mthca_eq *eq, u32 entry)
{
        unsigned long off = (entry & (eq->nent - 1)) * MTHCA_EQ_ENTRY_SIZE;
        return eq->page_list[off / PAGE_SIZE].buf + off % PAGE_SIZE;
}

static inline struct mthca_eqe *next_eqe_sw(struct mthca_eq *eq)
{
        struct mthca_eqe *eqe;
        eqe = get_eqe(eq, eq->cons_index);
        return (MTHCA_EQ_ENTRY_OWNER_HW & eqe->owner) ? NULL : eqe;
}

static inline void set_eqe_hw(struct mthca_eqe *eqe)
{
        eqe->owner =  MTHCA_EQ_ENTRY_OWNER_HW;
}

static void port_change(struct mthca_dev *dev, int port, int active)
{
        struct ib_event record;

        mthca_dbg(dev, "Port change to %s for port %d\n",
                  active ? "active" : "down", port);

        record.device = &dev->ib_dev;
        record.event  = active ? IB_EVENT_PORT_ACTIVE : IB_EVENT_PORT_ERR;
        record.element.port_num = port;

        ib_dispatch_event(&record);
}

static int mthca_eq_int(struct mthca_dev *dev, struct mthca_eq *eq)
{
        struct mthca_eqe *eqe;
        int disarm_cqn;
        int eqes_found = 0;
        int set_ci = 0;

        while ((eqe = next_eqe_sw(eq))) {
                /*
                 * Make sure we read EQ entry contents after we've
                 * checked the ownership bit.
                 */
                rmb();

                switch (eqe->type) {
                case MTHCA_EVENT_TYPE_COMP:
                        disarm_cqn = be32_to_cpu(eqe->event.comp.cqn) & 0xffffff;
                        disarm_cq(dev, eq->eqn, disarm_cqn);
                        mthca_cq_completion(dev, disarm_cqn);
                        break;

                case MTHCA_EVENT_TYPE_PATH_MIG:
                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                       IB_EVENT_PATH_MIG);
                        break;

                case MTHCA_EVENT_TYPE_COMM_EST:
                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                       IB_EVENT_COMM_EST);
                        break;

                case MTHCA_EVENT_TYPE_SQ_DRAINED:
                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                       IB_EVENT_SQ_DRAINED);
                        break;

                case MTHCA_EVENT_TYPE_SRQ_QP_LAST_WQE:
                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                       IB_EVENT_QP_LAST_WQE_REACHED);
                        break;

                case MTHCA_EVENT_TYPE_SRQ_LIMIT:
                        mthca_srq_event(dev, be32_to_cpu(eqe->event.srq.srqn) & 0xffffff,
                                        IB_EVENT_SRQ_LIMIT_REACHED);
                        break;

                case MTHCA_EVENT_TYPE_WQ_CATAS_ERROR:
                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                       IB_EVENT_QP_FATAL);
                        break;

                case MTHCA_EVENT_TYPE_PATH_MIG_FAILED:
                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                       IB_EVENT_PATH_MIG_ERR);
                        break;

                case MTHCA_EVENT_TYPE_WQ_INVAL_REQ_ERROR:
                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                       IB_EVENT_QP_REQ_ERR);
                        break;

                case MTHCA_EVENT_TYPE_WQ_ACCESS_ERROR:
                        mthca_qp_event(dev, be32_to_cpu(eqe->event.qp.qpn) & 0xffffff,
                                       IB_EVENT_QP_ACCESS_ERR);
                        break;

                case MTHCA_EVENT_TYPE_CMD:
                        mthca_cmd_event(dev,
                                        be16_to_cpu(eqe->event.cmd.token),
                                        eqe->event.cmd.status,
                                        be64_to_cpu(eqe->event.cmd.out_param));
                        break;

                case MTHCA_EVENT_TYPE_PORT_CHANGE:
                        port_change(dev,
                                    (be32_to_cpu(eqe->event.port_change.port) >> 28) & 3,
                                    eqe->subtype == 0x4);
                        break;

                case MTHCA_EVENT_TYPE_CQ_ERROR:
                        mthca_warn(dev, "CQ %s on CQN %06x\n",
                                   eqe->event.cq_err.syndrome == 1 ?
                                   "overrun" : "access violation",
                                   be32_to_cpu(eqe->event.cq_err.cqn) & 0xffffff);
                        mthca_cq_event(dev, be32_to_cpu(eqe->event.cq_err.cqn),
                                       IB_EVENT_CQ_ERR);
                        break;

                case MTHCA_EVENT_TYPE_EQ_OVERFLOW:
                        mthca_warn(dev, "EQ overrun on EQN %d\n", eq->eqn);
                        break;

                case MTHCA_EVENT_TYPE_EEC_CATAS_ERROR:
                case MTHCA_EVENT_TYPE_SRQ_CATAS_ERROR:
                case MTHCA_EVENT_TYPE_LOCAL_CATAS_ERROR:
                case MTHCA_EVENT_TYPE_ECC_DETECT:
                default:
                        mthca_warn(dev, "Unhandled event %02x(%02x) on EQ %d\n",
                                   eqe->type, eqe->subtype, eq->eqn);
                        break;
                }

                set_eqe_hw(eqe);
                ++eq->cons_index;
                eqes_found = 1;
                ++set_ci;

                /*
                 * The HCA will think the queue has overflowed if we
                 * don't tell it we've been processing events.  We
                 * create our EQs with MTHCA_NUM_SPARE_EQE extra
                 * entries, so we must update our consumer index at
                 * least that often.
                 */
                if (unlikely(set_ci >= MTHCA_NUM_SPARE_EQE)) {
                        /*
                         * Conditional on hca_type is OK here because
                         * this is a rare case, not the fast path.
                         */
                        set_eq_ci(dev, eq, eq->cons_index);
                        set_ci = 0;
                }
        }

        /*
         * Rely on caller to set consumer index so that we don't have
         * to test hca_type in our interrupt handling fast path.
         */
        return eqes_found;
}

static irqreturn_t mthca_tavor_interrupt(int irq, void *dev_ptr)
{
        struct mthca_dev *dev = dev_ptr;
        u32 ecr;
        int i;

        if (dev->eq_table.clr_mask)
                writel(dev->eq_table.clr_mask, dev->eq_table.clr_int);

        ecr = readl(dev->eq_regs.tavor.ecr_base + 4);
        if (!ecr)
                return IRQ_NONE;

        writel(ecr, dev->eq_regs.tavor.ecr_base +
               MTHCA_ECR_CLR_BASE - MTHCA_ECR_BASE + 4);

        for (i = 0; i < MTHCA_NUM_EQ; ++i)
                if (ecr & dev->eq_table.eq[i].eqn_mask) {
                        if (mthca_eq_int(dev, &dev->eq_table.eq[i]))
                                tavor_set_eq_ci(dev, &dev->eq_table.eq[i],
                                                dev->eq_table.eq[i].cons_index);
                        tavor_eq_req_not(dev, dev->eq_table.eq[i].eqn);
                }

        return IRQ_HANDLED;
}

static irqreturn_t mthca_tavor_msi_x_interrupt(int irq, void *eq_ptr)
{
        struct mthca_eq  *eq  = eq_ptr;
        struct mthca_dev *dev = eq->dev;

        mthca_eq_int(dev, eq);
        tavor_set_eq_ci(dev, eq, eq->cons_index);
        tavor_eq_req_not(dev, eq->eqn);

        /* MSI-X vectors always belong to us */
        return IRQ_HANDLED;
}

static irqreturn_t mthca_arbel_interrupt(int irq, void *dev_ptr)
{
        struct mthca_dev *dev = dev_ptr;
        int work = 0;
        int i;

        if (dev->eq_table.clr_mask)
                writel(dev->eq_table.clr_mask, dev->eq_table.clr_int);

        for (i = 0; i < MTHCA_NUM_EQ; ++i)
                if (mthca_eq_int(dev, &dev->eq_table.eq[i])) {
                        work = 1;
                        arbel_set_eq_ci(dev, &dev->eq_table.eq[i],
                                        dev->eq_table.eq[i].cons_index);
                }

        arbel_eq_req_not(dev, dev->eq_table.arm_mask);

        return IRQ_RETVAL(work);
}

static irqreturn_t mthca_arbel_msi_x_interrupt(int irq, void *eq_ptr)
{
        struct mthca_eq  *eq  = eq_ptr;
        struct mthca_dev *dev = eq->dev;

        mthca_eq_int(dev, eq);
        arbel_set_eq_ci(dev, eq, eq->cons_index);
        arbel_eq_req_not(dev, eq->eqn_mask);

        /* MSI-X vectors always belong to us */
        return IRQ_HANDLED;
}

static int mthca_create_eq(struct mthca_dev *dev,
                           int nent,
                           u8 intr,
                           struct mthca_eq *eq)
{
        int npages;
        u64 *dma_list = NULL;
        dma_addr_t t;
        struct mthca_mailbox *mailbox;
        struct mthca_eq_context *eq_context;
        int err = -ENOMEM;
        int i;

        eq->dev  = dev;
        eq->nent = roundup_pow_of_two(max(nent, 2));
        npages = ALIGN(eq->nent * MTHCA_EQ_ENTRY_SIZE, PAGE_SIZE) / PAGE_SIZE;

        eq->page_list = kmalloc(npages * sizeof *eq->page_list,
                                GFP_KERNEL);
        if (!eq->page_list)
                goto err_out;

        for (i = 0; i < npages; ++i)
                eq->page_list[i].buf = NULL;

        dma_list = kmalloc(npages * sizeof *dma_list, GFP_KERNEL);
        if (!dma_list)
                goto err_out_free;

        mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
        if (IS_ERR(mailbox))
                goto err_out_free;
        eq_context = mailbox->buf;

        for (i = 0; i < npages; ++i) {
                eq->page_list[i].buf = dma_alloc_coherent(&dev->pdev->dev,
                                                          PAGE_SIZE, &t, GFP_KERNEL);
                if (!eq->page_list[i].buf)
                        goto err_out_free_pages;

                dma_list[i] = t;
                dma_unmap_addr_set(&eq->page_list[i], mapping, t);

                clear_page(eq->page_list[i].buf);
        }

        for (i = 0; i < eq->nent; ++i)
                set_eqe_hw(get_eqe(eq, i));

        eq->eqn = mthca_alloc(&dev->eq_table.alloc);
        if (eq->eqn == -1)
                goto err_out_free_pages;

        err = mthca_mr_alloc_phys(dev, dev->driver_pd.pd_num,
                                  dma_list, PAGE_SHIFT, npages,
                                  0, npages * PAGE_SIZE,
                                  MTHCA_MPT_FLAG_LOCAL_WRITE |
                                  MTHCA_MPT_FLAG_LOCAL_READ,
                                  &eq->mr);
        if (err)
                goto err_out_free_eq;

        memset(eq_context, 0, sizeof *eq_context);
        eq_context->flags           = cpu_to_be32(MTHCA_EQ_STATUS_OK   |
                                                  MTHCA_EQ_OWNER_HW    |
                                                  MTHCA_EQ_STATE_ARMED |
                                                  MTHCA_EQ_FLAG_TR);
        if (mthca_is_memfree(dev))
                eq_context->flags  |= cpu_to_be32(MTHCA_EQ_STATE_ARBEL);

        eq_context->logsize_usrpage = cpu_to_be32((ffs(eq->nent) - 1) << 24);
        if (mthca_is_memfree(dev)) {
                eq_context->arbel_pd = cpu_to_be32(dev->driver_pd.pd_num);
        } else {
                eq_context->logsize_usrpage |= cpu_to_be32(dev->driver_uar.index);
                eq_context->tavor_pd         = cpu_to_be32(dev->driver_pd.pd_num);
        }
        eq_context->intr            = intr;
        eq_context->lkey            = cpu_to_be32(eq->mr.ibmr.lkey);

        err = mthca_SW2HW_EQ(dev, mailbox, eq->eqn);
        if (err) {
                mthca_warn(dev, "SW2HW_EQ returned %d\n", err);
                goto err_out_free_mr;
        }

        kfree(dma_list);
        mthca_free_mailbox(dev, mailbox);

        eq->eqn_mask   = swab32(1 << eq->eqn);
        eq->cons_index = 0;

        dev->eq_table.arm_mask |= eq->eqn_mask;

        mthca_dbg(dev, "Allocated EQ %d with %d entries\n",
                  eq->eqn, eq->nent);

        return err;

 err_out_free_mr:
        mthca_free_mr(dev, &eq->mr);

 err_out_free_eq:
        mthca_free(&dev->eq_table.alloc, eq->eqn);

 err_out_free_pages:
        for (i = 0; i < npages; ++i)
                if (eq->page_list[i].buf)
                        dma_free_coherent(&dev->pdev->dev, PAGE_SIZE,
                                          eq->page_list[i].buf,
                                          dma_unmap_addr(&eq->page_list[i],
                                                         mapping));

        mthca_free_mailbox(dev, mailbox);

 err_out_free:
        kfree(eq->page_list);
        kfree(dma_list);

 err_out:
        return err;
}

static void mthca_free_eq(struct mthca_dev *dev,
                          struct mthca_eq *eq)
{
        struct mthca_mailbox *mailbox;
        int err;
        int npages = (eq->nent * MTHCA_EQ_ENTRY_SIZE + PAGE_SIZE - 1) /
                PAGE_SIZE;
        int i;

        mailbox = mthca_alloc_mailbox(dev, GFP_KERNEL);
        if (IS_ERR(mailbox))
                return;

        err = mthca_HW2SW_EQ(dev, mailbox, eq->eqn);
        if (err)
                mthca_warn(dev, "HW2SW_EQ returned %d\n", err);

        dev->eq_table.arm_mask &= ~eq->eqn_mask;

        if (0) {
                mthca_dbg(dev, "Dumping EQ context %02x:\n", eq->eqn);
                for (i = 0; i < sizeof (struct mthca_eq_context) / 4; ++i) {
                        if (i % 4 == 0)
                                printk("[%02x] ", i * 4);
                        printk(" %08x", be32_to_cpup(mailbox->buf + i * 4));
                        if ((i + 1) % 4 == 0)
                                printk("\n");
                }
        }

        mthca_free_mr(dev, &eq->mr);
        for (i = 0; i < npages; ++i)
                pci_free_consistent(dev->pdev, PAGE_SIZE,
                                    eq->page_list[i].buf,
                                    dma_unmap_addr(&eq->page_list[i], mapping));

        kfree(eq->page_list);
        mthca_free_mailbox(dev, mailbox);
}

static void mthca_free_irqs(struct mthca_dev *dev)
{
        int i;

        if (dev->eq_table.have_irq)
                free_irq(dev->pdev->irq, dev);
        for (i = 0; i < MTHCA_NUM_EQ; ++i)
                if (dev->eq_table.eq[i].have_irq) {
                        free_irq(dev->eq_table.eq[i].msi_x_vector,
                                 dev->eq_table.eq + i);
                        dev->eq_table.eq[i].have_irq = 0;
                }
}

static int mthca_map_reg(struct mthca_dev *dev,
                         unsigned long offset, unsigned long size,
                         void __iomem **map)
{
        phys_addr_t base = pci_resource_start(dev->pdev, 0);

        *map = ioremap(base + offset, size);
        if (!*map)
                return -ENOMEM;

        return 0;
}

static int mthca_map_eq_regs(struct mthca_dev *dev)
{
        if (mthca_is_memfree(dev)) {
                /*
                 * We assume that the EQ arm and EQ set CI registers
                 * fall within the first BAR.  We can't trust the
                 * values firmware gives us, since those addresses are
                 * valid on the HCA's side of the PCI bus but not
                 * necessarily the host side.
                 */
                if (mthca_map_reg(dev, (pci_resource_len(dev->pdev, 0) - 1) &
                                  dev->fw.arbel.clr_int_base, MTHCA_CLR_INT_SIZE,
                                  &dev->clr_base)) {
                        mthca_err(dev, "Couldn't map interrupt clear register, "
                                  "aborting.\n");
                        return -ENOMEM;
                }

                /*
                 * Add 4 because we limit ourselves to EQs 0 ... 31,
                 * so we only need the low word of the register.
                 */
                if (mthca_map_reg(dev, ((pci_resource_len(dev->pdev, 0) - 1) &
                                        dev->fw.arbel.eq_arm_base) + 4, 4,
                                  &dev->eq_regs.arbel.eq_arm)) {
                        mthca_err(dev, "Couldn't map EQ arm register, aborting.\n");
                        iounmap(dev->clr_base);
                        return -ENOMEM;
                }

                if (mthca_map_reg(dev, (pci_resource_len(dev->pdev, 0) - 1) &
                                  dev->fw.arbel.eq_set_ci_base,
                                  MTHCA_EQ_SET_CI_SIZE,
                                  &dev->eq_regs.arbel.eq_set_ci_base)) {
                        mthca_err(dev, "Couldn't map EQ CI register, aborting.\n");
                        iounmap(dev->eq_regs.arbel.eq_arm);
                        iounmap(dev->clr_base);
                        return -ENOMEM;
                }
        } else {
                if (mthca_map_reg(dev, MTHCA_CLR_INT_BASE, MTHCA_CLR_INT_SIZE,
                                  &dev->clr_base)) {
                        mthca_err(dev, "Couldn't map interrupt clear register, "
                                  "aborting.\n");
                        return -ENOMEM;
                }

                if (mthca_map_reg(dev, MTHCA_ECR_BASE,
                                  MTHCA_ECR_SIZE + MTHCA_ECR_CLR_SIZE,
                                  &dev->eq_regs.tavor.ecr_base)) {
                        mthca_err(dev, "Couldn't map ecr register, "
                                  "aborting.\n");
                        iounmap(dev->clr_base);
                        return -ENOMEM;
                }
        }

        return 0;

}

static void mthca_unmap_eq_regs(struct mthca_dev *dev)
{
        if (mthca_is_memfree(dev)) {
                iounmap(dev->eq_regs.arbel.eq_set_ci_base);
                iounmap(dev->eq_regs.arbel.eq_arm);
                iounmap(dev->clr_base);
        } else {
                iounmap(dev->eq_regs.tavor.ecr_base);
                iounmap(dev->clr_base);
        }
}

int mthca_map_eq_icm(struct mthca_dev *dev, u64 icm_virt)
{
        int ret;

        /*
         * We assume that mapping one page is enough for the whole EQ
         * context table.  This is fine with all current HCAs, because
         * we only use 32 EQs and each EQ uses 32 bytes of context
         * memory, or 1 KB total.
         */
        dev->eq_table.icm_virt = icm_virt;
        dev->eq_table.icm_page = alloc_page(GFP_HIGHUSER);
        if (!dev->eq_table.icm_page)
                return -ENOMEM;
        dev->eq_table.icm_dma  = pci_map_page(dev->pdev, dev->eq_table.icm_page, 0,
                                              PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
        if (pci_dma_mapping_error(dev->pdev, dev->eq_table.icm_dma)) {
                __free_page(dev->eq_table.icm_page);
                return -ENOMEM;
        }

        ret = mthca_MAP_ICM_page(dev, dev->eq_table.icm_dma, icm_virt);
        if (ret) {
                pci_unmap_page(dev->pdev, dev->eq_table.icm_dma, PAGE_SIZE,
                               PCI_DMA_BIDIRECTIONAL);
                __free_page(dev->eq_table.icm_page);
        }

        return ret;
}

void mthca_unmap_eq_icm(struct mthca_dev *dev)
{
        mthca_UNMAP_ICM(dev, dev->eq_table.icm_virt, 1);
        pci_unmap_page(dev->pdev, dev->eq_table.icm_dma, PAGE_SIZE,
                       PCI_DMA_BIDIRECTIONAL);
        __free_page(dev->eq_table.icm_page);
}

int mthca_init_eq_table(struct mthca_dev *dev)
{
        int err;
        u8 intr;
        int i;

        err = mthca_alloc_init(&dev->eq_table.alloc,
                               dev->limits.num_eqs,
                               dev->limits.num_eqs - 1,
                               dev->limits.reserved_eqs);
        if (err)
                return err;

        err = mthca_map_eq_regs(dev);
        if (err)
                goto err_out_free;

        if (dev->mthca_flags & MTHCA_FLAG_MSI_X) {
                dev->eq_table.clr_mask = 0;
        } else {
                dev->eq_table.clr_mask =
                        swab32(1 << (dev->eq_table.inta_pin & 31));
                dev->eq_table.clr_int  = dev->clr_base +
                        (dev->eq_table.inta_pin < 32 ? 4 : 0);
        }

        dev->eq_table.arm_mask = 0;

        intr = dev->eq_table.inta_pin;

        err = mthca_create_eq(dev, dev->limits.num_cqs + MTHCA_NUM_SPARE_EQE,
                              (dev->mthca_flags & MTHCA_FLAG_MSI_X) ? 128 : intr,
                              &dev->eq_table.eq[MTHCA_EQ_COMP]);
        if (err)
                goto err_out_unmap;

        err = mthca_create_eq(dev, MTHCA_NUM_ASYNC_EQE + MTHCA_NUM_SPARE_EQE,
                              (dev->mthca_flags & MTHCA_FLAG_MSI_X) ? 129 : intr,
                              &dev->eq_table.eq[MTHCA_EQ_ASYNC]);
        if (err)
                goto err_out_comp;

        err = mthca_create_eq(dev, MTHCA_NUM_CMD_EQE + MTHCA_NUM_SPARE_EQE,
                              (dev->mthca_flags & MTHCA_FLAG_MSI_X) ? 130 : intr,
                              &dev->eq_table.eq[MTHCA_EQ_CMD]);
        if (err)
                goto err_out_async;

        if (dev->mthca_flags & MTHCA_FLAG_MSI_X) {
                static const char *eq_name[] = {
                        [MTHCA_EQ_COMP]  = DRV_NAME "-comp",
                        [MTHCA_EQ_ASYNC] = DRV_NAME "-async",
                        [MTHCA_EQ_CMD]   = DRV_NAME "-cmd"
                };

                for (i = 0; i < MTHCA_NUM_EQ; ++i) {
                        snprintf(dev->eq_table.eq[i].irq_name,
                                 IB_DEVICE_NAME_MAX,
                                 "%s@pci:%s", eq_name[i],
                                 pci_name(dev->pdev));
                        err = request_irq(dev->eq_table.eq[i].msi_x_vector,
                                          mthca_is_memfree(dev) ?
                                          mthca_arbel_msi_x_interrupt :
                                          mthca_tavor_msi_x_interrupt,
                                          0, dev->eq_table.eq[i].irq_name,
                                          dev->eq_table.eq + i);
                        if (err)
                                goto err_out_cmd;
                        dev->eq_table.eq[i].have_irq = 1;
                }
        } else {
                snprintf(dev->eq_table.eq[0].irq_name, IB_DEVICE_NAME_MAX,
                         DRV_NAME "@pci:%s", pci_name(dev->pdev));
                err = request_irq(dev->pdev->irq,
                                  mthca_is_memfree(dev) ?
                                  mthca_arbel_interrupt :
                                  mthca_tavor_interrupt,
                                  IRQF_SHARED, dev->eq_table.eq[0].irq_name, dev);
                if (err)
                        goto err_out_cmd;
                dev->eq_table.have_irq = 1;
        }

        err = mthca_MAP_EQ(dev, async_mask(dev),
                           0, dev->eq_table.eq[MTHCA_EQ_ASYNC].eqn);
        if (err)
                mthca_warn(dev, "MAP_EQ for async EQ %d failed (%d)\n",
                           dev->eq_table.eq[MTHCA_EQ_ASYNC].eqn, err);

        err = mthca_MAP_EQ(dev, MTHCA_CMD_EVENT_MASK,
                           0, dev->eq_table.eq[MTHCA_EQ_CMD].eqn);
        if (err)
                mthca_warn(dev, "MAP_EQ for cmd EQ %d failed (%d)\n",
                           dev->eq_table.eq[MTHCA_EQ_CMD].eqn, err);

        for (i = 0; i < MTHCA_NUM_EQ; ++i)
                if (mthca_is_memfree(dev))
                        arbel_eq_req_not(dev, dev->eq_table.eq[i].eqn_mask);
                else
                        tavor_eq_req_not(dev, dev->eq_table.eq[i].eqn);

        return 0;

err_out_cmd:
        mthca_free_irqs(dev);
        mthca_free_eq(dev, &dev->eq_table.eq[MTHCA_EQ_CMD]);

err_out_async:
        mthca_free_eq(dev, &dev->eq_table.eq[MTHCA_EQ_ASYNC]);

err_out_comp:
        mthca_free_eq(dev, &dev->eq_table.eq[MTHCA_EQ_COMP]);

err_out_unmap:
        mthca_unmap_eq_regs(dev);

err_out_free:
        mthca_alloc_cleanup(&dev->eq_table.alloc);
        return err;
}

void mthca_cleanup_eq_table(struct mthca_dev *dev)
{
        int i;

        mthca_free_irqs(dev);

        mthca_MAP_EQ(dev, async_mask(dev),
                     1, dev->eq_table.eq[MTHCA_EQ_ASYNC].eqn);
        mthca_MAP_EQ(dev, MTHCA_CMD_EVENT_MASK,
                     1, dev->eq_table.eq[MTHCA_EQ_CMD].eqn);

        for (i = 0; i < MTHCA_NUM_EQ; ++i)
                mthca_free_eq(dev, &dev->eq_table.eq[i]);

        mthca_unmap_eq_regs(dev);

        mthca_alloc_cleanup(&dev->eq_table.alloc);
}