/**********************************************************************
 * Author: Cavium, Inc.
 *
 * Contact: support@cavium.com
 *          Please include "LiquidIO" in the subject.
 *
 * Copyright (c) 2003-2016 Cavium, Inc.
 *
 * This file is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, Version 2, as
 * published by the Free Software Foundation.
 *
 * This file is distributed in the hope that it will be useful, but
 * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
 * NONINFRINGEMENT.  See the GNU General Public License for more
 * details.
 **********************************************************************/
#include <linux/pci.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
#include "liquidio_common.h"
#include "octeon_droq.h"
#include "octeon_iq.h"
#include "response_manager.h"
#include "octeon_device.h"
#include "octeon_main.h"
#include "octeon_network.h"
#include "cn66xx_device.h"
#include "cn23xx_pf_device.h"
#include "cn23xx_vf_device.h"

struct iq_post_status {
        int status;
        int index;
};

static void check_db_timeout(struct work_struct *work);
static void  __check_db_timeout(struct octeon_device *oct, u64 iq_no);

static void (*reqtype_free_fn[MAX_OCTEON_DEVICES][REQTYPE_LAST + 1]) (void *);

static inline int IQ_INSTR_MODE_64B(struct octeon_device *oct, int iq_no)
{
        struct octeon_instr_queue *iq =
            (struct octeon_instr_queue *)oct->instr_queue[iq_no];
        return iq->iqcmd_64B;
}

#define IQ_INSTR_MODE_32B(oct, iq_no)  (!IQ_INSTR_MODE_64B(oct, iq_no))

/* Define this to return the request status comaptible to old code */
/*#define OCTEON_USE_OLD_REQ_STATUS*/

/* Return 0 on success, 1 on failure */
int octeon_init_instr_queue(struct octeon_device *oct,
                            union oct_txpciq txpciq,
                            u32 num_descs)
{
        struct octeon_instr_queue *iq;
        struct octeon_iq_config *conf = NULL;
        u32 iq_no = (u32)txpciq.s.q_no;
        u32 q_size;
        struct cavium_wq *db_wq;
        int numa_node = dev_to_node(&oct->pci_dev->dev);

        if (OCTEON_CN6XXX(oct))
                conf = &(CFG_GET_IQ_CFG(CHIP_CONF(oct, cn6xxx)));
        else if (OCTEON_CN23XX_PF(oct))
                conf = &(CFG_GET_IQ_CFG(CHIP_CONF(oct, cn23xx_pf)));
        else if (OCTEON_CN23XX_VF(oct))
                conf = &(CFG_GET_IQ_CFG(CHIP_CONF(oct, cn23xx_vf)));

        if (!conf) {
                dev_err(&oct->pci_dev->dev, "Unsupported Chip %x\n",
                        oct->chip_id);
                return 1;
        }

        q_size = (u32)conf->instr_type * num_descs;

        iq = oct->instr_queue[iq_no];

        iq->oct_dev = oct;

        iq->base_addr = lio_dma_alloc(oct, q_size, &iq->base_addr_dma);
        if (!iq->base_addr) {
                dev_err(&oct->pci_dev->dev, "Cannot allocate memory for instr queue %d\n",
                        iq_no);
                return 1;
        }

        iq->max_count = num_descs;

        /* Initialize a list to holds requests that have been posted to Octeon
         * but has yet to be fetched by octeon
         */
        iq->request_list = vmalloc_node((sizeof(*iq->request_list) * num_descs),
                                               numa_node);
        if (!iq->request_list)
                iq->request_list =
                        vmalloc(array_size(num_descs,
                                           sizeof(*iq->request_list)));
        if (!iq->request_list) {
                lio_dma_free(oct, q_size, iq->base_addr, iq->base_addr_dma);
                dev_err(&oct->pci_dev->dev, "Alloc failed for IQ[%d] nr free list\n",
                        iq_no);
                return 1;
        }

        memset(iq->request_list, 0, sizeof(*iq->request_list) * num_descs);

        dev_dbg(&oct->pci_dev->dev, "IQ[%d]: base: %p basedma: %pad count: %d\n",
                iq_no, iq->base_addr, &iq->base_addr_dma, iq->max_count);

        iq->txpciq.u64 = txpciq.u64;
        iq->fill_threshold = (u32)conf->db_min;
        iq->fill_cnt = 0;
        iq->host_write_index = 0;
        iq->octeon_read_index = 0;
        iq->flush_index = 0;
        iq->last_db_time = 0;
        iq->do_auto_flush = 1;
        iq->db_timeout = (u32)conf->db_timeout;
        atomic_set(&iq->instr_pending, 0);
        iq->pkts_processed = 0;

        /* Initialize the spinlock for this instruction queue */
        spin_lock_init(&iq->lock);
        if (iq_no == 0) {
                iq->allow_soft_cmds = true;
                spin_lock_init(&iq->post_lock);
        } else {
                iq->allow_soft_cmds = false;
        }

        spin_lock_init(&iq->iq_flush_running_lock);

        oct->io_qmask.iq |= BIT_ULL(iq_no);

        /* Set the 32B/64B mode for each input queue */
        oct->io_qmask.iq64B |= ((conf->instr_type == 64) << iq_no);
        iq->iqcmd_64B = (conf->instr_type == 64);

        oct->fn_list.setup_iq_regs(oct, iq_no);

        oct->check_db_wq[iq_no].wq = alloc_workqueue("check_iq_db",
                                                     WQ_MEM_RECLAIM,
                                                     0);
        if (!oct->check_db_wq[iq_no].wq) {
                vfree(iq->request_list);
                iq->request_list = NULL;
                lio_dma_free(oct, q_size, iq->base_addr, iq->base_addr_dma);
                dev_err(&oct->pci_dev->dev, "check db wq create failed for iq %d\n",
                        iq_no);
                return 1;
        }

        db_wq = &oct->check_db_wq[iq_no];

        INIT_DELAYED_WORK(&db_wq->wk.work, check_db_timeout);
        db_wq->wk.ctxptr = oct;
        db_wq->wk.ctxul = iq_no;
        queue_delayed_work(db_wq->wq, &db_wq->wk.work, msecs_to_jiffies(1));

        return 0;
}

int octeon_delete_instr_queue(struct octeon_device *oct, u32 iq_no)
{
        u64 desc_size = 0, q_size;
        struct octeon_instr_queue *iq = oct->instr_queue[iq_no];

        cancel_delayed_work_sync(&oct->check_db_wq[iq_no].wk.work);
        destroy_workqueue(oct->check_db_wq[iq_no].wq);

        if (OCTEON_CN6XXX(oct))
                desc_size =
                    CFG_GET_IQ_INSTR_TYPE(CHIP_CONF(oct, cn6xxx));
        else if (OCTEON_CN23XX_PF(oct))
                desc_size =
                    CFG_GET_IQ_INSTR_TYPE(CHIP_CONF(oct, cn23xx_pf));
        else if (OCTEON_CN23XX_VF(oct))
                desc_size =
                    CFG_GET_IQ_INSTR_TYPE(CHIP_CONF(oct, cn23xx_vf));

        vfree(iq->request_list);

        if (iq->base_addr) {
                q_size = iq->max_count * desc_size;
                lio_dma_free(oct, (u32)q_size, iq->base_addr,
                             iq->base_addr_dma);
                oct->io_qmask.iq &= ~(1ULL << iq_no);
                vfree(oct->instr_queue[iq_no]);
                oct->instr_queue[iq_no] = NULL;
                oct->num_iqs--;
                return 0;
        }
        return 1;
}

/* Return 0 on success, 1 on failure */
int octeon_setup_iq(struct octeon_device *oct,
                    int ifidx,
                    int q_index,
                    union oct_txpciq txpciq,
                    u32 num_descs,
                    void *app_ctx)
{
        u32 iq_no = (u32)txpciq.s.q_no;
        int numa_node = dev_to_node(&oct->pci_dev->dev);

        if (oct->instr_queue[iq_no]) {
                dev_dbg(&oct->pci_dev->dev, "IQ is in use. Cannot create the IQ: %d again\n",
                        iq_no);
                oct->instr_queue[iq_no]->txpciq.u64 = txpciq.u64;
                oct->instr_queue[iq_no]->app_ctx = app_ctx;
                return 0;
        }
        oct->instr_queue[iq_no] =
            vzalloc_node(sizeof(struct octeon_instr_queue), numa_node);
        if (!oct->instr_queue[iq_no])
                oct->instr_queue[iq_no] =
                    vzalloc(sizeof(struct octeon_instr_queue));
        if (!oct->instr_queue[iq_no])
                return 1;


        oct->instr_queue[iq_no]->q_index = q_index;
        oct->instr_queue[iq_no]->app_ctx = app_ctx;
        oct->instr_queue[iq_no]->ifidx = ifidx;

        if (octeon_init_instr_queue(oct, txpciq, num_descs)) {
                vfree(oct->instr_queue[iq_no]);
                oct->instr_queue[iq_no] = NULL;
                return 1;
        }

        oct->num_iqs++;
        if (oct->fn_list.enable_io_queues(oct)) {
                octeon_delete_instr_queue(oct, iq_no);
                return 1;
        }

        return 0;
}

int lio_wait_for_instr_fetch(struct octeon_device *oct)
{
        int i, retry = 1000, pending, instr_cnt = 0;

        do {
                instr_cnt = 0;

                for (i = 0; i < MAX_OCTEON_INSTR_QUEUES(oct); i++) {
                        if (!(oct->io_qmask.iq & BIT_ULL(i)))
                                continue;
                        pending =
                            atomic_read(&oct->instr_queue[i]->instr_pending);
                        if (pending)
                                __check_db_timeout(oct, i);
                        instr_cnt += pending;
                }

                if (instr_cnt == 0)
                        break;

                schedule_timeout_uninterruptible(1);

        } while (retry-- && instr_cnt);

        return instr_cnt;
}

static inline void
ring_doorbell(struct octeon_device *oct, struct octeon_instr_queue *iq)
{
        if (atomic_read(&oct->status) == OCT_DEV_RUNNING) {
                writel(iq->fill_cnt, iq->doorbell_reg);
                /* make sure doorbell write goes through */
                iq->fill_cnt = 0;
                iq->last_db_time = jiffies;
                return;
        }
}

void
octeon_ring_doorbell_locked(struct octeon_device *oct, u32 iq_no)
{
        struct octeon_instr_queue *iq;

        iq = oct->instr_queue[iq_no];
        spin_lock(&iq->post_lock);
        if (iq->fill_cnt)
                ring_doorbell(oct, iq);
        spin_unlock(&iq->post_lock);
}

static inline void __copy_cmd_into_iq(struct octeon_instr_queue *iq,
                                      u8 *cmd)
{
        u8 *iqptr, cmdsize;

        cmdsize = ((iq->iqcmd_64B) ? 64 : 32);
        iqptr = iq->base_addr + (cmdsize * iq->host_write_index);

        memcpy(iqptr, cmd, cmdsize);
}

static inline struct iq_post_status
__post_command2(struct octeon_instr_queue *iq, u8 *cmd)
{
        struct iq_post_status st;

        st.status = IQ_SEND_OK;

        /* This ensures that the read index does not wrap around to the same
         * position if queue gets full before Octeon could fetch any instr.
         */
        if (atomic_read(&iq->instr_pending) >= (s32)(iq->max_count - 1)) {
                st.status = IQ_SEND_FAILED;
                st.index = -1;
                return st;
        }

        if (atomic_read(&iq->instr_pending) >= (s32)(iq->max_count - 2))
                st.status = IQ_SEND_STOP;

        __copy_cmd_into_iq(iq, cmd);

        /* "index" is returned, host_write_index is modified. */
        st.index = iq->host_write_index;
        iq->host_write_index = incr_index(iq->host_write_index, 1,
                                          iq->max_count);
        iq->fill_cnt++;

        /* Flush the command into memory. We need to be sure the data is in
         * memory before indicating that the instruction is pending.
         */
        wmb();

        atomic_inc(&iq->instr_pending);

        return st;
}

int
octeon_register_reqtype_free_fn(struct octeon_device *oct, int reqtype,
                                void (*fn)(void *))
{
        if (reqtype > REQTYPE_LAST) {
                dev_err(&oct->pci_dev->dev, "%s: Invalid reqtype: %d\n",
                        __func__, reqtype);
                return -EINVAL;
        }

        reqtype_free_fn[oct->octeon_id][reqtype] = fn;

        return 0;
}

static inline void
__add_to_request_list(struct octeon_instr_queue *iq,
                      int idx, void *buf, int reqtype)
{
        iq->request_list[idx].buf = buf;
        iq->request_list[idx].reqtype = reqtype;
}

/* Can only run in process context */
int
lio_process_iq_request_list(struct octeon_device *oct,
                            struct octeon_instr_queue *iq, u32 napi_budget)
{
        struct cavium_wq *cwq = &oct->dma_comp_wq;
        int reqtype;
        void *buf;
        u32 old = iq->flush_index;
        u32 inst_count = 0;
        unsigned int pkts_compl = 0, bytes_compl = 0;
        struct octeon_soft_command *sc;
        unsigned long flags;

        while (old != iq->octeon_read_index) {
                reqtype = iq->request_list[old].reqtype;
                buf     = iq->request_list[old].buf;

                if (reqtype == REQTYPE_NONE)
                        goto skip_this;

                octeon_update_tx_completion_counters(buf, reqtype, &pkts_compl,
                                                     &bytes_compl);

                switch (reqtype) {
                case REQTYPE_NORESP_NET:
                case REQTYPE_NORESP_NET_SG:
                case REQTYPE_RESP_NET_SG:
                        reqtype_free_fn[oct->octeon_id][reqtype](buf);
                        break;
                case REQTYPE_RESP_NET:
                case REQTYPE_SOFT_COMMAND:
                        sc = buf;
                        /* We're expecting a response from Octeon.
                         * It's up to lio_process_ordered_list() to
                         * process  sc. Add sc to the ordered soft
                         * command response list because we expect
                         * a response from Octeon.
                         */
                        spin_lock_irqsave(&oct->response_list
                                          [OCTEON_ORDERED_SC_LIST].lock, flags);
                        atomic_inc(&oct->response_list
                                   [OCTEON_ORDERED_SC_LIST].pending_req_count);
                        list_add_tail(&sc->node, &oct->response_list
                                [OCTEON_ORDERED_SC_LIST].head);
                        spin_unlock_irqrestore(&oct->response_list
                                               [OCTEON_ORDERED_SC_LIST].lock,
                                               flags);
                        break;
                default:
                        dev_err(&oct->pci_dev->dev,
                                "%s Unknown reqtype: %d buf: %p at idx %d\n",
                                __func__, reqtype, buf, old);
                }

                iq->request_list[old].buf = NULL;
                iq->request_list[old].reqtype = 0;

 skip_this:
                inst_count++;
                old = incr_index(old, 1, iq->max_count);

                if ((napi_budget) && (inst_count >= napi_budget))
                        break;
        }
        if (bytes_compl)
                octeon_report_tx_completion_to_bql(iq->app_ctx, pkts_compl,
                                                   bytes_compl);
        iq->flush_index = old;

        if (atomic_read(&oct->response_list
                        [OCTEON_ORDERED_SC_LIST].pending_req_count))
                queue_work(cwq->wq, &cwq->wk.work.work);

        return inst_count;
}

/* Can only be called from process context */
int
octeon_flush_iq(struct octeon_device *oct, struct octeon_instr_queue *iq,
                u32 napi_budget)
{
        u32 inst_processed = 0;
        u32 tot_inst_processed = 0;
        int tx_done = 1;

        if (!spin_trylock(&iq->iq_flush_running_lock))
                return tx_done;

        spin_lock_bh(&iq->lock);

        iq->octeon_read_index = oct->fn_list.update_iq_read_idx(iq);

        do {
                /* Process any outstanding IQ packets. */
                if (iq->flush_index == iq->octeon_read_index)
                        break;

                if (napi_budget)
                        inst_processed =
                                lio_process_iq_request_list(oct, iq,
                                                            napi_budget -
                                                            tot_inst_processed);
                else
                        inst_processed =
                                lio_process_iq_request_list(oct, iq, 0);

                if (inst_processed) {
                        iq->pkts_processed += inst_processed;
                        atomic_sub(inst_processed, &iq->instr_pending);
                        iq->stats.instr_processed += inst_processed;
                }

                tot_inst_processed += inst_processed;
        } while (tot_inst_processed < napi_budget);

        if (napi_budget && (tot_inst_processed >= napi_budget))
                tx_done = 0;

        iq->last_db_time = jiffies;

        spin_unlock_bh(&iq->lock);

        spin_unlock(&iq->iq_flush_running_lock);

        return tx_done;
}

/* Process instruction queue after timeout.
 * This routine gets called from a workqueue or when removing the module.
 */
static void __check_db_timeout(struct octeon_device *oct, u64 iq_no)
{
        struct octeon_instr_queue *iq;
        u64 next_time;

        if (!oct)
                return;

        iq = oct->instr_queue[iq_no];
        if (!iq)
                return;

        /* return immediately, if no work pending */
        if (!atomic_read(&iq->instr_pending))
                return;
        /* If jiffies - last_db_time < db_timeout do nothing  */
        next_time = iq->last_db_time + iq->db_timeout;
        if (!time_after(jiffies, (unsigned long)next_time))
                return;
        iq->last_db_time = jiffies;

        /* Flush the instruction queue */
        octeon_flush_iq(oct, iq, 0);

        lio_enable_irq(NULL, iq);
}

/* Called by the Poll thread at regular intervals to check the instruction
 * queue for commands to be posted and for commands that were fetched by Octeon.
 */
static void check_db_timeout(struct work_struct *work)
{
        struct cavium_wk *wk = (struct cavium_wk *)work;
        struct octeon_device *oct = (struct octeon_device *)wk->ctxptr;
        u64 iq_no = wk->ctxul;
        struct cavium_wq *db_wq = &oct->check_db_wq[iq_no];
        u32 delay = 10;

        __check_db_timeout(oct, iq_no);
        queue_delayed_work(db_wq->wq, &db_wq->wk.work, msecs_to_jiffies(delay));
}

int
octeon_send_command(struct octeon_device *oct, u32 iq_no,
                    u32 force_db, void *cmd, void *buf,
                    u32 datasize, u32 reqtype)
{
        int xmit_stopped;
        struct iq_post_status st;
        struct octeon_instr_queue *iq = oct->instr_queue[iq_no];

        /* Get the lock and prevent other tasks and tx interrupt handler from
         * running.
         */
        if (iq->allow_soft_cmds)
                spin_lock_bh(&iq->post_lock);

        st = __post_command2(iq, cmd);

        if (st.status != IQ_SEND_FAILED) {
                xmit_stopped = octeon_report_sent_bytes_to_bql(buf, reqtype);
                __add_to_request_list(iq, st.index, buf, reqtype);
                INCR_INSTRQUEUE_PKT_COUNT(oct, iq_no, bytes_sent, datasize);
                INCR_INSTRQUEUE_PKT_COUNT(oct, iq_no, instr_posted, 1);

                if (iq->fill_cnt >= MAX_OCTEON_FILL_COUNT || force_db ||
                    xmit_stopped || st.status == IQ_SEND_STOP)
                        ring_doorbell(oct, iq);
        } else {
                INCR_INSTRQUEUE_PKT_COUNT(oct, iq_no, instr_dropped, 1);
        }

        if (iq->allow_soft_cmds)
                spin_unlock_bh(&iq->post_lock);

        /* This is only done here to expedite packets being flushed
         * for cases where there are no IQ completion interrupts.
         */

        return st.status;
}

void
octeon_prepare_soft_command(struct octeon_device *oct,
                            struct octeon_soft_command *sc,
                            u8 opcode,
                            u8 subcode,
                            u32 irh_ossp,
                            u64 ossp0,
                            u64 ossp1)
{
        struct octeon_config *oct_cfg;
        struct octeon_instr_ih2 *ih2;
        struct octeon_instr_ih3 *ih3;
        struct octeon_instr_pki_ih3 *pki_ih3;
        struct octeon_instr_irh *irh;
        struct octeon_instr_rdp *rdp;

        WARN_ON(opcode > 15);
        WARN_ON(subcode > 127);

        oct_cfg = octeon_get_conf(oct);

        if (OCTEON_CN23XX_PF(oct) || OCTEON_CN23XX_VF(oct)) {
                ih3 = (struct octeon_instr_ih3 *)&sc->cmd.cmd3.ih3;

                ih3->pkind = oct->instr_queue[sc->iq_no]->txpciq.s.pkind;

                pki_ih3 = (struct octeon_instr_pki_ih3 *)&sc->cmd.cmd3.pki_ih3;

                pki_ih3->w           = 1;
                pki_ih3->raw         = 1;
                pki_ih3->utag        = 1;
                pki_ih3->uqpg        =
                        oct->instr_queue[sc->iq_no]->txpciq.s.use_qpg;
                pki_ih3->utt         = 1;
                pki_ih3->tag     = LIO_CONTROL;
                pki_ih3->tagtype = ATOMIC_TAG;
                pki_ih3->qpg         =
                        oct->instr_queue[sc->iq_no]->txpciq.s.ctrl_qpg;

                pki_ih3->pm          = 0x7;
                pki_ih3->sl          = 8;

                if (sc->datasize)
                        ih3->dlengsz = sc->datasize;

                irh            = (struct octeon_instr_irh *)&sc->cmd.cmd3.irh;
                irh->opcode    = opcode;
                irh->subcode   = subcode;

                /* opcode/subcode specific parameters (ossp) */
                irh->ossp       = irh_ossp;
                sc->cmd.cmd3.ossp[0] = ossp0;
                sc->cmd.cmd3.ossp[1] = ossp1;

                if (sc->rdatasize) {
                        rdp = (struct octeon_instr_rdp *)&sc->cmd.cmd3.rdp;
                        rdp->pcie_port = oct->pcie_port;
                        rdp->rlen      = sc->rdatasize;

                        irh->rflag =  1;
                        /*PKI IH3*/
                        /* pki_ih3 irh+ossp[0]+ossp[1]+rdp+rptr = 48 bytes */
                        ih3->fsz    = LIO_SOFTCMDRESP_IH3;
                } else {
                        irh->rflag =  0;
                        /*PKI IH3*/
                        /* pki_h3 + irh + ossp[0] + ossp[1] = 32 bytes */
                        ih3->fsz    = LIO_PCICMD_O3;
                }

        } else {
                ih2          = (struct octeon_instr_ih2 *)&sc->cmd.cmd2.ih2;
                ih2->tagtype = ATOMIC_TAG;
                ih2->tag     = LIO_CONTROL;
                ih2->raw     = 1;
                ih2->grp     = CFG_GET_CTRL_Q_GRP(oct_cfg);

                if (sc->datasize) {
                        ih2->dlengsz = sc->datasize;
                        ih2->rs = 1;
                }

                irh            = (struct octeon_instr_irh *)&sc->cmd.cmd2.irh;
                irh->opcode    = opcode;
                irh->subcode   = subcode;

                /* opcode/subcode specific parameters (ossp) */
                irh->ossp       = irh_ossp;
                sc->cmd.cmd2.ossp[0] = ossp0;
                sc->cmd.cmd2.ossp[1] = ossp1;

                if (sc->rdatasize) {
                        rdp = (struct octeon_instr_rdp *)&sc->cmd.cmd2.rdp;
                        rdp->pcie_port = oct->pcie_port;
                        rdp->rlen      = sc->rdatasize;

                        irh->rflag =  1;
                        /* irh+ossp[0]+ossp[1]+rdp+rptr = 40 bytes */
                        ih2->fsz   = LIO_SOFTCMDRESP_IH2;
                } else {
                        irh->rflag =  0;
                        /* irh + ossp[0] + ossp[1] = 24 bytes */
                        ih2->fsz   = LIO_PCICMD_O2;
                }
        }
}

int octeon_send_soft_command(struct octeon_device *oct,
                             struct octeon_soft_command *sc)
{
        struct octeon_instr_queue *iq;
        struct octeon_instr_ih2 *ih2;
        struct octeon_instr_ih3 *ih3;
        struct octeon_instr_irh *irh;
        u32 len;

        iq = oct->instr_queue[sc->iq_no];
        if (!iq->allow_soft_cmds) {
                dev_err(&oct->pci_dev->dev, "Soft commands are not allowed on Queue %d\n",
                        sc->iq_no);
                INCR_INSTRQUEUE_PKT_COUNT(oct, sc->iq_no, instr_dropped, 1);
                return IQ_SEND_FAILED;
        }

        if (OCTEON_CN23XX_PF(oct) || OCTEON_CN23XX_VF(oct)) {
                ih3 =  (struct octeon_instr_ih3 *)&sc->cmd.cmd3.ih3;
                if (ih3->dlengsz) {
                        WARN_ON(!sc->dmadptr);
                        sc->cmd.cmd3.dptr = sc->dmadptr;
                }
                irh = (struct octeon_instr_irh *)&sc->cmd.cmd3.irh;
                if (irh->rflag) {
                        WARN_ON(!sc->dmarptr);
                        WARN_ON(!sc->status_word);
                        *sc->status_word = COMPLETION_WORD_INIT;
                        sc->cmd.cmd3.rptr = sc->dmarptr;
                }
                len = (u32)ih3->dlengsz;
        } else {
                ih2 = (struct octeon_instr_ih2 *)&sc->cmd.cmd2.ih2;
                if (ih2->dlengsz) {
                        WARN_ON(!sc->dmadptr);
                        sc->cmd.cmd2.dptr = sc->dmadptr;
                }
                irh = (struct octeon_instr_irh *)&sc->cmd.cmd2.irh;
                if (irh->rflag) {
                        WARN_ON(!sc->dmarptr);
                        WARN_ON(!sc->status_word);
                        *sc->status_word = COMPLETION_WORD_INIT;
                        sc->cmd.cmd2.rptr = sc->dmarptr;
                }
                len = (u32)ih2->dlengsz;
        }

        sc->expiry_time = jiffies + msecs_to_jiffies(LIO_SC_MAX_TMO_MS);

        return (octeon_send_command(oct, sc->iq_no, 1, &sc->cmd, sc,
                                    len, REQTYPE_SOFT_COMMAND));
}

int octeon_setup_sc_buffer_pool(struct octeon_device *oct)
{
        int i;
        u64 dma_addr;
        struct octeon_soft_command *sc;

        INIT_LIST_HEAD(&oct->sc_buf_pool.head);
        spin_lock_init(&oct->sc_buf_pool.lock);
        atomic_set(&oct->sc_buf_pool.alloc_buf_count, 0);

        for (i = 0; i < MAX_SOFT_COMMAND_BUFFERS; i++) {
                sc = (struct octeon_soft_command *)
                        lio_dma_alloc(oct,
                                      SOFT_COMMAND_BUFFER_SIZE,
                                          (dma_addr_t *)&dma_addr);
                if (!sc) {
                        octeon_free_sc_buffer_pool(oct);
                        return 1;
                }

                sc->dma_addr = dma_addr;
                sc->size = SOFT_COMMAND_BUFFER_SIZE;

                list_add_tail(&sc->node, &oct->sc_buf_pool.head);
        }

        return 0;
}

int octeon_free_sc_done_list(struct octeon_device *oct)
{
        struct octeon_response_list *done_sc_list, *zombie_sc_list;
        struct octeon_soft_command *sc;
        struct list_head *tmp, *tmp2;
        spinlock_t *sc_lists_lock; /* lock for response_list */

        done_sc_list = &oct->response_list[OCTEON_DONE_SC_LIST];
        zombie_sc_list = &oct->response_list[OCTEON_ZOMBIE_SC_LIST];

        if (!atomic_read(&done_sc_list->pending_req_count))
                return 0;

        sc_lists_lock = &oct->response_list[OCTEON_ORDERED_SC_LIST].lock;

        spin_lock_bh(sc_lists_lock);

        list_for_each_safe(tmp, tmp2, &done_sc_list->head) {
                sc = list_entry(tmp, struct octeon_soft_command, node);

                if (READ_ONCE(sc->caller_is_done)) {
                        list_del(&sc->node);
                        atomic_dec(&done_sc_list->pending_req_count);

                        if (*sc->status_word == COMPLETION_WORD_INIT) {
                                /* timeout; move sc to zombie list */
                                list_add_tail(&sc->node, &zombie_sc_list->head);
                                atomic_inc(&zombie_sc_list->pending_req_count);
                        } else {
                                octeon_free_soft_command(oct, sc);
                        }
                }
        }

        spin_unlock_bh(sc_lists_lock);

        return 0;
}

int octeon_free_sc_zombie_list(struct octeon_device *oct)
{
        struct octeon_response_list *zombie_sc_list;
        struct octeon_soft_command *sc;
        struct list_head *tmp, *tmp2;
        spinlock_t *sc_lists_lock; /* lock for response_list */

        zombie_sc_list = &oct->response_list[OCTEON_ZOMBIE_SC_LIST];
        sc_lists_lock = &oct->response_list[OCTEON_ORDERED_SC_LIST].lock;

        spin_lock_bh(sc_lists_lock);

        list_for_each_safe(tmp, tmp2, &zombie_sc_list->head) {
                list_del(tmp);
                atomic_dec(&zombie_sc_list->pending_req_count);
                sc = list_entry(tmp, struct octeon_soft_command, node);
                octeon_free_soft_command(oct, sc);
        }

        spin_unlock_bh(sc_lists_lock);

        return 0;
}

int octeon_free_sc_buffer_pool(struct octeon_device *oct)
{
        struct list_head *tmp, *tmp2;
        struct octeon_soft_command *sc;

        octeon_free_sc_zombie_list(oct);

        spin_lock_bh(&oct->sc_buf_pool.lock);

        list_for_each_safe(tmp, tmp2, &oct->sc_buf_pool.head) {
                list_del(tmp);

                sc = (struct octeon_soft_command *)tmp;

                lio_dma_free(oct, sc->size, sc, sc->dma_addr);
        }

        INIT_LIST_HEAD(&oct->sc_buf_pool.head);

        spin_unlock_bh(&oct->sc_buf_pool.lock);

        return 0;
}

struct octeon_soft_command *octeon_alloc_soft_command(struct octeon_device *oct,
                                                      u32 datasize,
                                                      u32 rdatasize,
                                                      u32 ctxsize)
{
        u64 dma_addr;
        u32 size;
        u32 offset = sizeof(struct octeon_soft_command);
        struct octeon_soft_command *sc = NULL;
        struct list_head *tmp;

        if (!rdatasize)
                rdatasize = 16;

        WARN_ON((offset + datasize + rdatasize + ctxsize) >
               SOFT_COMMAND_BUFFER_SIZE);

        spin_lock_bh(&oct->sc_buf_pool.lock);

        if (list_empty(&oct->sc_buf_pool.head)) {
                spin_unlock_bh(&oct->sc_buf_pool.lock);
                return NULL;
        }

        list_for_each(tmp, &oct->sc_buf_pool.head)
                break;

        list_del(tmp);

        atomic_inc(&oct->sc_buf_pool.alloc_buf_count);

        spin_unlock_bh(&oct->sc_buf_pool.lock);

        sc = (struct octeon_soft_command *)tmp;

        dma_addr = sc->dma_addr;
        size = sc->size;

        memset(sc, 0, sc->size);

        sc->dma_addr = dma_addr;
        sc->size = size;

        if (ctxsize) {
                sc->ctxptr = (u8 *)sc + offset;
                sc->ctxsize = ctxsize;
        }

        /* Start data at 128 byte boundary */
        offset = (offset + ctxsize + 127) & 0xffffff80;

        if (datasize) {
                sc->virtdptr = (u8 *)sc + offset;
                sc->dmadptr = dma_addr + offset;
                sc->datasize = datasize;
        }

        /* Start rdata at 128 byte boundary */
        offset = (offset + datasize + 127) & 0xffffff80;

        if (rdatasize) {
                WARN_ON(rdatasize < 16);
                sc->virtrptr = (u8 *)sc + offset;
                sc->dmarptr = dma_addr + offset;
                sc->rdatasize = rdatasize;
                sc->status_word = (u64 *)((u8 *)(sc->virtrptr) + rdatasize - 8);
        }

        return sc;
}

void octeon_free_soft_command(struct octeon_device *oct,
                              struct octeon_soft_command *sc)
{
        spin_lock_bh(&oct->sc_buf_pool.lock);

        list_add_tail(&sc->node, &oct->sc_buf_pool.head);

        atomic_dec(&oct->sc_buf_pool.alloc_buf_count);

        spin_unlock_bh(&oct->sc_buf_pool.lock);
}