/*
 * QLogic iSCSI HBA Driver
 * Copyright (c)  2003-2013 QLogic Corporation
 *
 * See LICENSE.qla4xxx for copyright and licensing details.
 */

#include "ql4_def.h"
#include "ql4_glbl.h"
#include "ql4_dbg.h"
#include "ql4_inline.h"

#include <scsi/scsi_tcq.h>

static int
qla4xxx_space_in_req_ring(struct scsi_qla_host *ha, uint16_t req_cnt)
{
        uint16_t cnt;

        /* Calculate number of free request entries. */
        if ((req_cnt + 2) >= ha->req_q_count) {
                cnt = (uint16_t) ha->isp_ops->rd_shdw_req_q_out(ha);
                if (ha->request_in < cnt)
                        ha->req_q_count = cnt - ha->request_in;
                else
                        ha->req_q_count = REQUEST_QUEUE_DEPTH -
                                                (ha->request_in - cnt);
        }

        /* Check if room for request in request ring. */
        if ((req_cnt + 2) < ha->req_q_count)
                return 1;
        else
                return 0;
}

static void qla4xxx_advance_req_ring_ptr(struct scsi_qla_host *ha)
{
        /* Advance request queue pointer */
        if (ha->request_in == (REQUEST_QUEUE_DEPTH - 1)) {
                ha->request_in = 0;
                ha->request_ptr = ha->request_ring;
        } else {
                ha->request_in++;
                ha->request_ptr++;
        }
}

/**
 * qla4xxx_get_req_pkt - returns a valid entry in request queue.
 * @ha: Pointer to host adapter structure.
 * @queue_entry: Pointer to pointer to queue entry structure
 *
 * This routine performs the following tasks:
 *      - returns the current request_in pointer (if queue not full)
 *      - advances the request_in pointer
 *      - checks for queue full
 **/
static int qla4xxx_get_req_pkt(struct scsi_qla_host *ha,
                               struct queue_entry **queue_entry)
{
        uint16_t req_cnt = 1;

        if (qla4xxx_space_in_req_ring(ha, req_cnt)) {
                *queue_entry = ha->request_ptr;
                memset(*queue_entry, 0, sizeof(**queue_entry));

                qla4xxx_advance_req_ring_ptr(ha);
                ha->req_q_count -= req_cnt;
                return QLA_SUCCESS;
        }

        return QLA_ERROR;
}

/**
 * qla4xxx_send_marker_iocb - issues marker iocb to HBA
 * @ha: Pointer to host adapter structure.
 * @ddb_entry: Pointer to device database entry
 * @lun: SCSI LUN
 * @marker_type: marker identifier
 *
 * This routine issues a marker IOCB.
 **/
int qla4xxx_send_marker_iocb(struct scsi_qla_host *ha,
        struct ddb_entry *ddb_entry, uint64_t lun, uint16_t mrkr_mod)
{
        struct qla4_marker_entry *marker_entry;
        unsigned long flags = 0;
        uint8_t status = QLA_SUCCESS;

        /* Acquire hardware specific lock */
        spin_lock_irqsave(&ha->hardware_lock, flags);

        /* Get pointer to the queue entry for the marker */
        if (qla4xxx_get_req_pkt(ha, (struct queue_entry **) &marker_entry) !=
            QLA_SUCCESS) {
                status = QLA_ERROR;
                goto exit_send_marker;
        }

        /* Put the marker in the request queue */
        marker_entry->hdr.entryType = ET_MARKER;
        marker_entry->hdr.entryCount = 1;
        marker_entry->target = cpu_to_le16(ddb_entry->fw_ddb_index);
        marker_entry->modifier = cpu_to_le16(mrkr_mod);
        int_to_scsilun(lun, &marker_entry->lun);
        wmb();

        /* Tell ISP it's got a new I/O request */
        ha->isp_ops->queue_iocb(ha);

exit_send_marker:
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
        return status;
}

static struct continuation_t1_entry *
qla4xxx_alloc_cont_entry(struct scsi_qla_host *ha)
{
        struct continuation_t1_entry *cont_entry;

        cont_entry = (struct continuation_t1_entry *)ha->request_ptr;

        qla4xxx_advance_req_ring_ptr(ha);

        /* Load packet defaults */
        cont_entry->hdr.entryType = ET_CONTINUE;
        cont_entry->hdr.entryCount = 1;
        cont_entry->hdr.systemDefined = (uint8_t) cpu_to_le16(ha->request_in);

        return cont_entry;
}

static uint16_t qla4xxx_calc_request_entries(uint16_t dsds)
{
        uint16_t iocbs;

        iocbs = 1;
        if (dsds > COMMAND_SEG) {
                iocbs += (dsds - COMMAND_SEG) / CONTINUE_SEG;
                if ((dsds - COMMAND_SEG) % CONTINUE_SEG)
                        iocbs++;
        }
        return iocbs;
}

static void qla4xxx_build_scsi_iocbs(struct srb *srb,
                                     struct command_t3_entry *cmd_entry,
                                     uint16_t tot_dsds)
{
        struct scsi_qla_host *ha;
        uint16_t avail_dsds;
        struct data_seg_a64 *cur_dsd;
        struct scsi_cmnd *cmd;
        struct scatterlist *sg;
        int i;

        cmd = srb->cmd;
        ha = srb->ha;

        if (!scsi_bufflen(cmd) || cmd->sc_data_direction == DMA_NONE) {
                /* No data being transferred */
                cmd_entry->ttlByteCnt = __constant_cpu_to_le32(0);
                return;
        }

        avail_dsds = COMMAND_SEG;
        cur_dsd = (struct data_seg_a64 *) & (cmd_entry->dataseg[0]);

        scsi_for_each_sg(cmd, sg, tot_dsds, i) {
                dma_addr_t sle_dma;

                /* Allocate additional continuation packets? */
                if (avail_dsds == 0) {
                        struct continuation_t1_entry *cont_entry;

                        cont_entry = qla4xxx_alloc_cont_entry(ha);
                        cur_dsd =
                                (struct data_seg_a64 *)
                                &cont_entry->dataseg[0];
                        avail_dsds = CONTINUE_SEG;
                }

                sle_dma = sg_dma_address(sg);
                cur_dsd->base.addrLow = cpu_to_le32(LSDW(sle_dma));
                cur_dsd->base.addrHigh = cpu_to_le32(MSDW(sle_dma));
                cur_dsd->count = cpu_to_le32(sg_dma_len(sg));
                avail_dsds--;

                cur_dsd++;
        }
}

void qla4_83xx_queue_iocb(struct scsi_qla_host *ha)
{
        writel(ha->request_in, &ha->qla4_83xx_reg->req_q_in);
        readl(&ha->qla4_83xx_reg->req_q_in);
}

void qla4_83xx_complete_iocb(struct scsi_qla_host *ha)
{
        writel(ha->response_out, &ha->qla4_83xx_reg->rsp_q_out);
        readl(&ha->qla4_83xx_reg->rsp_q_out);
}

/**
 * qla4_82xx_queue_iocb - Tell ISP it's got new request(s)
 * @ha: pointer to host adapter structure.
 *
 * This routine notifies the ISP that one or more new request
 * queue entries have been placed on the request queue.
 **/
void qla4_82xx_queue_iocb(struct scsi_qla_host *ha)
{
        uint32_t dbval = 0;

        dbval = 0x14 | (ha->func_num << 5);
        dbval = dbval | (0 << 8) | (ha->request_in << 16);

        qla4_82xx_wr_32(ha, ha->nx_db_wr_ptr, ha->request_in);
}

/**
 * qla4_82xx_complete_iocb - Tell ISP we're done with response(s)
 * @ha: pointer to host adapter structure.
 *
 * This routine notifies the ISP that one or more response/completion
 * queue entries have been processed by the driver.
 * This also clears the interrupt.
 **/
void qla4_82xx_complete_iocb(struct scsi_qla_host *ha)
{
        writel(ha->response_out, &ha->qla4_82xx_reg->rsp_q_out);
        readl(&ha->qla4_82xx_reg->rsp_q_out);
}

/**
 * qla4xxx_queue_iocb - Tell ISP it's got new request(s)
 * @ha: pointer to host adapter structure.
 *
 * This routine is notifies the ISP that one or more new request
 * queue entries have been placed on the request queue.
 **/
void qla4xxx_queue_iocb(struct scsi_qla_host *ha)
{
        writel(ha->request_in, &ha->reg->req_q_in);
        readl(&ha->reg->req_q_in);
}

/**
 * qla4xxx_complete_iocb - Tell ISP we're done with response(s)
 * @ha: pointer to host adapter structure.
 *
 * This routine is notifies the ISP that one or more response/completion
 * queue entries have been processed by the driver.
 * This also clears the interrupt.
 **/
void qla4xxx_complete_iocb(struct scsi_qla_host *ha)
{
        writel(ha->response_out, &ha->reg->rsp_q_out);
        readl(&ha->reg->rsp_q_out);
}

/**
 * qla4xxx_send_command_to_isp - issues command to HBA
 * @ha: pointer to host adapter structure.
 * @srb: pointer to SCSI Request Block to be sent to ISP
 *
 * This routine is called by qla4xxx_queuecommand to build an ISP
 * command and pass it to the ISP for execution.
 **/
int qla4xxx_send_command_to_isp(struct scsi_qla_host *ha, struct srb * srb)
{
        struct scsi_cmnd *cmd = srb->cmd;
        struct ddb_entry *ddb_entry;
        struct command_t3_entry *cmd_entry;
        int nseg;
        uint16_t tot_dsds;
        uint16_t req_cnt;
        unsigned long flags;
        uint32_t index;

        /* Get real lun and adapter */
        ddb_entry = srb->ddb;

        tot_dsds = 0;

        /* Acquire hardware specific lock */
        spin_lock_irqsave(&ha->hardware_lock, flags);

        index = (uint32_t)cmd->request->tag;

        /*
         * Check to see if adapter is online before placing request on
         * request queue.  If a reset occurs and a request is in the queue,
         * the firmware will still attempt to process the request, retrieving
         * garbage for pointers.
         */
        if (!test_bit(AF_ONLINE, &ha->flags)) {
                DEBUG2(printk("scsi%ld: %s: Adapter OFFLINE! "
                              "Do not issue command.\n",
                              ha->host_no, __func__));
                goto queuing_error;
        }

        /* Calculate the number of request entries needed. */
        nseg = scsi_dma_map(cmd);
        if (nseg < 0)
                goto queuing_error;
        tot_dsds = nseg;

        req_cnt = qla4xxx_calc_request_entries(tot_dsds);
        if (!qla4xxx_space_in_req_ring(ha, req_cnt))
                goto queuing_error;

        /* total iocbs active */
        if ((ha->iocb_cnt + req_cnt) >= ha->iocb_hiwat)
                goto queuing_error;

        /* Build command packet */
        cmd_entry = (struct command_t3_entry *) ha->request_ptr;
        memset(cmd_entry, 0, sizeof(struct command_t3_entry));
        cmd_entry->hdr.entryType = ET_COMMAND;
        cmd_entry->handle = cpu_to_le32(index);
        cmd_entry->target = cpu_to_le16(ddb_entry->fw_ddb_index);

        int_to_scsilun(cmd->device->lun, &cmd_entry->lun);
        cmd_entry->ttlByteCnt = cpu_to_le32(scsi_bufflen(cmd));
        memcpy(cmd_entry->cdb, cmd->cmnd, cmd->cmd_len);
        cmd_entry->dataSegCnt = cpu_to_le16(tot_dsds);
        cmd_entry->hdr.entryCount = req_cnt;

        /* Set data transfer direction control flags
         * NOTE: Look at data_direction bits iff there is data to be
         *       transferred, as the data direction bit is sometimed filled
         *       in when there is no data to be transferred */
        cmd_entry->control_flags = CF_NO_DATA;
        if (scsi_bufflen(cmd)) {
                if (cmd->sc_data_direction == DMA_TO_DEVICE)
                        cmd_entry->control_flags = CF_WRITE;
                else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
                        cmd_entry->control_flags = CF_READ;

                ha->bytes_xfered += scsi_bufflen(cmd);
                if (ha->bytes_xfered & ~0xFFFFF){
                        ha->total_mbytes_xferred += ha->bytes_xfered >> 20;
                        ha->bytes_xfered &= 0xFFFFF;
                }
        }

        /* Set tagged queueing control flags */
        cmd_entry->control_flags |= CF_SIMPLE_TAG;

        qla4xxx_advance_req_ring_ptr(ha);
        qla4xxx_build_scsi_iocbs(srb, cmd_entry, tot_dsds);
        wmb();

        srb->cmd->host_scribble = (unsigned char *)(unsigned long)index;

        /* update counters */
        srb->state = SRB_ACTIVE_STATE;
        srb->flags |= SRB_DMA_VALID;

        /* Track IOCB used */
        ha->iocb_cnt += req_cnt;
        srb->iocb_cnt = req_cnt;
        ha->req_q_count -= req_cnt;

        ha->isp_ops->queue_iocb(ha);
        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        return QLA_SUCCESS;

queuing_error:
        if (tot_dsds)
                scsi_dma_unmap(cmd);

        spin_unlock_irqrestore(&ha->hardware_lock, flags);

        return QLA_ERROR;
}

int qla4xxx_send_passthru0(struct iscsi_task *task)
{
        struct passthru0 *passthru_iocb;
        struct iscsi_session *sess = task->conn->session;
        struct ddb_entry *ddb_entry = sess->dd_data;
        struct scsi_qla_host *ha = ddb_entry->ha;
        struct ql4_task_data *task_data = task->dd_data;
        uint16_t ctrl_flags = 0;
        unsigned long flags;
        int ret = QLA_ERROR;

        spin_lock_irqsave(&ha->hardware_lock, flags);
        task_data->iocb_req_cnt = 1;
        /* Put the IOCB on the request queue */
        if (!qla4xxx_space_in_req_ring(ha, task_data->iocb_req_cnt))
                goto queuing_error;

        passthru_iocb = (struct passthru0 *) ha->request_ptr;

        memset(passthru_iocb, 0, sizeof(struct passthru0));
        passthru_iocb->hdr.entryType = ET_PASSTHRU0;
        passthru_iocb->hdr.systemDefined = SD_ISCSI_PDU;
        passthru_iocb->hdr.entryCount = task_data->iocb_req_cnt;
        passthru_iocb->handle = task->itt;
        passthru_iocb->target = cpu_to_le16(ddb_entry->fw_ddb_index);
        passthru_iocb->timeout = cpu_to_le16(PT_DEFAULT_TIMEOUT);

        /* Setup the out & in DSDs */
        if (task_data->req_len) {
                memcpy((uint8_t *)task_data->req_buffer +
                       sizeof(struct iscsi_hdr), task->data, task->data_count);
                ctrl_flags |= PT_FLAG_SEND_BUFFER;
                passthru_iocb->out_dsd.base.addrLow =
                                        cpu_to_le32(LSDW(task_data->req_dma));
                passthru_iocb->out_dsd.base.addrHigh =
                                        cpu_to_le32(MSDW(task_data->req_dma));
                passthru_iocb->out_dsd.count =
                                        cpu_to_le32(task->data_count +
                                                    sizeof(struct iscsi_hdr));
        }
        if (task_data->resp_len) {
                passthru_iocb->in_dsd.base.addrLow =
                                        cpu_to_le32(LSDW(task_data->resp_dma));
                passthru_iocb->in_dsd.base.addrHigh =
                                        cpu_to_le32(MSDW(task_data->resp_dma));
                passthru_iocb->in_dsd.count =
                        cpu_to_le32(task_data->resp_len);
        }

        ctrl_flags |= (PT_FLAG_ISCSI_PDU | PT_FLAG_WAIT_4_RESPONSE);
        passthru_iocb->control_flags = cpu_to_le16(ctrl_flags);

        /* Update the request pointer */
        qla4xxx_advance_req_ring_ptr(ha);
        wmb();

        /* Track IOCB used */
        ha->iocb_cnt += task_data->iocb_req_cnt;
        ha->req_q_count -= task_data->iocb_req_cnt;
        ha->isp_ops->queue_iocb(ha);
        ret = QLA_SUCCESS;

queuing_error:
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
        return ret;
}

static struct mrb *qla4xxx_get_new_mrb(struct scsi_qla_host *ha)
{
        struct mrb *mrb;

        mrb = kzalloc(sizeof(*mrb), GFP_KERNEL);
        if (!mrb)
                return mrb;

        mrb->ha = ha;
        return mrb;
}

static int qla4xxx_send_mbox_iocb(struct scsi_qla_host *ha, struct mrb *mrb,
                                  uint32_t *in_mbox)
{
        int rval = QLA_SUCCESS;
        uint32_t i;
        unsigned long flags;
        uint32_t index = 0;

        /* Acquire hardware specific lock */
        spin_lock_irqsave(&ha->hardware_lock, flags);

        /* Get pointer to the queue entry for the marker */
        rval = qla4xxx_get_req_pkt(ha, (struct queue_entry **) &(mrb->mbox));
        if (rval != QLA_SUCCESS)
                goto exit_mbox_iocb;

        index = ha->mrb_index;
        /* get valid mrb index*/
        for (i = 0; i < MAX_MRB; i++) {
                index++;
                if (index == MAX_MRB)
                        index = 1;
                if (ha->active_mrb_array[index] == NULL) {
                        ha->mrb_index = index;
                        break;
                }
        }

        mrb->iocb_cnt = 1;
        ha->active_mrb_array[index] = mrb;
        mrb->mbox->handle = index;
        mrb->mbox->hdr.entryType = ET_MBOX_CMD;
        mrb->mbox->hdr.entryCount = mrb->iocb_cnt;
        memcpy(mrb->mbox->in_mbox, in_mbox, 32);
        mrb->mbox_cmd = in_mbox[0];
        wmb();

        ha->iocb_cnt += mrb->iocb_cnt;
        ha->isp_ops->queue_iocb(ha);
exit_mbox_iocb:
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
        return rval;
}

int qla4xxx_ping_iocb(struct scsi_qla_host *ha, uint32_t options,
                      uint32_t payload_size, uint32_t pid, uint8_t *ipaddr)
{
        uint32_t in_mbox[8];
        struct mrb *mrb = NULL;
        int rval = QLA_SUCCESS;

        memset(in_mbox, 0, sizeof(in_mbox));

        mrb = qla4xxx_get_new_mrb(ha);
        if (!mrb) {
                DEBUG2(ql4_printk(KERN_WARNING, ha, "%s: fail to get new mrb\n",
                                  __func__));
                rval = QLA_ERROR;
                goto exit_ping;
        }

        in_mbox[0] = MBOX_CMD_PING;
        in_mbox[1] = options;
        memcpy(&in_mbox[2], &ipaddr[0], 4);
        memcpy(&in_mbox[3], &ipaddr[4], 4);
        memcpy(&in_mbox[4], &ipaddr[8], 4);
        memcpy(&in_mbox[5], &ipaddr[12], 4);
        in_mbox[6] = payload_size;

        mrb->pid = pid;
        rval = qla4xxx_send_mbox_iocb(ha, mrb, in_mbox);

        if (rval != QLA_SUCCESS)
                goto exit_ping;

        return rval;
exit_ping:
        kfree(mrb);
        return rval;
}