// SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
/* Copyright 2021 Marvell. All rights reserved. */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <asm/byteorder.h>
#include <linux/qed/common_hsi.h>
#include <linux/qed/storage_common.h>
#include <linux/qed/nvmetcp_common.h>
#include <linux/qed/qed_nvmetcp_if.h>
#include "qed_nvmetcp_fw_funcs.h"

#define NVMETCP_NUM_SGES_IN_CACHE 0x4

bool nvmetcp_is_slow_sgl(u16 num_sges, bool small_mid_sge)
{
        return (num_sges > SCSI_NUM_SGES_SLOW_SGL_THR && small_mid_sge);
}

void init_scsi_sgl_context(struct scsi_sgl_params *ctx_sgl_params,
                           struct scsi_cached_sges *ctx_data_desc,
                           struct storage_sgl_task_params *sgl_params)
{
        u8 num_sges_to_init = (u8)(sgl_params->num_sges > NVMETCP_NUM_SGES_IN_CACHE ?
                                   NVMETCP_NUM_SGES_IN_CACHE : sgl_params->num_sges);
        u8 sge_index;

        /* sgl params */
        ctx_sgl_params->sgl_addr.lo = cpu_to_le32(sgl_params->sgl_phys_addr.lo);
        ctx_sgl_params->sgl_addr.hi = cpu_to_le32(sgl_params->sgl_phys_addr.hi);
        ctx_sgl_params->sgl_total_length = cpu_to_le32(sgl_params->total_buffer_size);
        ctx_sgl_params->sgl_num_sges = cpu_to_le16(sgl_params->num_sges);

        for (sge_index = 0; sge_index < num_sges_to_init; sge_index++) {
                ctx_data_desc->sge[sge_index].sge_addr.lo =
                        cpu_to_le32(sgl_params->sgl[sge_index].sge_addr.lo);
                ctx_data_desc->sge[sge_index].sge_addr.hi =
                        cpu_to_le32(sgl_params->sgl[sge_index].sge_addr.hi);
                ctx_data_desc->sge[sge_index].sge_len =
                        cpu_to_le32(sgl_params->sgl[sge_index].sge_len);
        }
}

static inline u32 calc_rw_task_size(struct nvmetcp_task_params *task_params,
                                    enum nvmetcp_task_type task_type)
{
        u32 io_size;

        if (task_type == NVMETCP_TASK_TYPE_HOST_WRITE)
                io_size = task_params->tx_io_size;
        else
                io_size = task_params->rx_io_size;

        if (unlikely(!io_size))
                return 0;

        return io_size;
}

static inline void init_sqe(struct nvmetcp_task_params *task_params,
                            struct storage_sgl_task_params *sgl_task_params,
                            enum nvmetcp_task_type task_type)
{
        if (!task_params->sqe)
                return;

        memset(task_params->sqe, 0, sizeof(*task_params->sqe));
        task_params->sqe->task_id = cpu_to_le16(task_params->itid);

        switch (task_type) {
        case NVMETCP_TASK_TYPE_HOST_WRITE: {
                u32 buf_size = 0;
                u32 num_sges = 0;

                SET_FIELD(task_params->sqe->contlen_cdbsize,
                          NVMETCP_WQE_CDB_SIZE_OR_NVMETCP_CMD, 1);
                SET_FIELD(task_params->sqe->flags, NVMETCP_WQE_WQE_TYPE,
                          NVMETCP_WQE_TYPE_NORMAL);
                if (task_params->tx_io_size) {
                        if (task_params->send_write_incapsule)
                                buf_size = calc_rw_task_size(task_params, task_type);

                        if (nvmetcp_is_slow_sgl(sgl_task_params->num_sges,
                                                sgl_task_params->small_mid_sge))
                                num_sges = NVMETCP_WQE_NUM_SGES_SLOWIO;
                        else
                                num_sges = min((u16)sgl_task_params->num_sges,
                                               (u16)SCSI_NUM_SGES_SLOW_SGL_THR);
                }
                SET_FIELD(task_params->sqe->flags, NVMETCP_WQE_NUM_SGES, num_sges);
                SET_FIELD(task_params->sqe->contlen_cdbsize, NVMETCP_WQE_CONT_LEN, buf_size);
        } break;

        case NVMETCP_TASK_TYPE_HOST_READ: {
                SET_FIELD(task_params->sqe->flags, NVMETCP_WQE_WQE_TYPE,
                          NVMETCP_WQE_TYPE_NORMAL);
                SET_FIELD(task_params->sqe->contlen_cdbsize,
                          NVMETCP_WQE_CDB_SIZE_OR_NVMETCP_CMD, 1);
        } break;

        case NVMETCP_TASK_TYPE_INIT_CONN_REQUEST: {
                SET_FIELD(task_params->sqe->flags, NVMETCP_WQE_WQE_TYPE,
                          NVMETCP_WQE_TYPE_MIDDLE_PATH);

                if (task_params->tx_io_size) {
                        SET_FIELD(task_params->sqe->contlen_cdbsize, NVMETCP_WQE_CONT_LEN,
                                  task_params->tx_io_size);
                        SET_FIELD(task_params->sqe->flags, NVMETCP_WQE_NUM_SGES,
                                  min((u16)sgl_task_params->num_sges,
                                      (u16)SCSI_NUM_SGES_SLOW_SGL_THR));
                }
        } break;

        case NVMETCP_TASK_TYPE_CLEANUP:
                SET_FIELD(task_params->sqe->flags, NVMETCP_WQE_WQE_TYPE,
                          NVMETCP_WQE_TYPE_TASK_CLEANUP);

        default:
                break;
        }
}

/* The following function initializes of NVMeTCP task params */
static inline void
init_nvmetcp_task_params(struct e5_nvmetcp_task_context *context,
                         struct nvmetcp_task_params *task_params,
                         enum nvmetcp_task_type task_type)
{
        context->ystorm_st_context.state.cccid = task_params->host_cccid;
        SET_FIELD(context->ustorm_st_context.error_flags, USTORM_NVMETCP_TASK_ST_CTX_NVME_TCP, 1);
        context->ustorm_st_context.nvme_tcp_opaque_lo = cpu_to_le32(task_params->opq.lo);
        context->ustorm_st_context.nvme_tcp_opaque_hi = cpu_to_le32(task_params->opq.hi);
}

/* The following function initializes default values to all tasks */
static inline void
init_default_nvmetcp_task(struct nvmetcp_task_params *task_params,
                          void *pdu_header, void *nvme_cmd,
                          enum nvmetcp_task_type task_type)
{
        struct e5_nvmetcp_task_context *context = task_params->context;
        const u8 val_byte = context->mstorm_ag_context.cdu_validation;
        u8 dw_index;

        memset(context, 0, sizeof(*context));
        init_nvmetcp_task_params(context, task_params,
                                 (enum nvmetcp_task_type)task_type);

        /* Swapping requirements used below, will be removed in future FW versions */
        if (task_type == NVMETCP_TASK_TYPE_HOST_WRITE ||
            task_type == NVMETCP_TASK_TYPE_HOST_READ) {
                for (dw_index = 0;
                     dw_index < QED_NVMETCP_CMN_HDR_SIZE / sizeof(u32);
                     dw_index++)
                        context->ystorm_st_context.pdu_hdr.task_hdr.reg[dw_index] =
                                cpu_to_le32(__swab32(((u32 *)pdu_header)[dw_index]));

                for (dw_index = QED_NVMETCP_CMN_HDR_SIZE / sizeof(u32);
                     dw_index < QED_NVMETCP_CMD_HDR_SIZE / sizeof(u32);
                     dw_index++)
                        context->ystorm_st_context.pdu_hdr.task_hdr.reg[dw_index] =
                                cpu_to_le32(__swab32(((u32 *)nvme_cmd)[dw_index - 2]));
        } else {
                for (dw_index = 0;
                     dw_index < QED_NVMETCP_NON_IO_HDR_SIZE / sizeof(u32);
                     dw_index++)
                        context->ystorm_st_context.pdu_hdr.task_hdr.reg[dw_index] =
                                cpu_to_le32(__swab32(((u32 *)pdu_header)[dw_index]));
        }

        /* M-Storm Context: */
        context->mstorm_ag_context.cdu_validation = val_byte;
        context->mstorm_st_context.task_type = (u8)(task_type);
        context->mstorm_ag_context.task_cid = cpu_to_le16(task_params->conn_icid);

        /* Ustorm Context: */
        SET_FIELD(context->ustorm_ag_context.flags1, E5_USTORM_NVMETCP_TASK_AG_CTX_R2T2RECV, 1);
        context->ustorm_st_context.task_type = (u8)(task_type);
        context->ustorm_st_context.cq_rss_number = task_params->cq_rss_number;
        context->ustorm_ag_context.icid = cpu_to_le16(task_params->conn_icid);
}

/* The following function initializes the U-Storm Task Contexts */
static inline void
init_ustorm_task_contexts(struct ustorm_nvmetcp_task_st_ctx *ustorm_st_context,
                          struct e5_ustorm_nvmetcp_task_ag_ctx *ustorm_ag_context,
                          u32 remaining_recv_len,
                          u32 expected_data_transfer_len, u8 num_sges,
                          bool tx_dif_conn_err_en)
{
        /* Remaining data to be received in bytes. Used in validations*/
        ustorm_st_context->rem_rcv_len = cpu_to_le32(remaining_recv_len);
        ustorm_ag_context->exp_data_acked = cpu_to_le32(expected_data_transfer_len);
        ustorm_st_context->exp_data_transfer_len = cpu_to_le32(expected_data_transfer_len);
        SET_FIELD(ustorm_st_context->reg1_map, REG1_NUM_SGES, num_sges);
        SET_FIELD(ustorm_ag_context->flags2, E5_USTORM_NVMETCP_TASK_AG_CTX_DIF_ERROR_CF_EN,
                  tx_dif_conn_err_en ? 1 : 0);
}

/* The following function initializes Local Completion Contexts: */
static inline void
set_local_completion_context(struct e5_nvmetcp_task_context *context)
{
        SET_FIELD(context->ystorm_st_context.state.flags,
                  YSTORM_NVMETCP_TASK_STATE_LOCAL_COMP, 1);
        SET_FIELD(context->ustorm_st_context.flags,
                  USTORM_NVMETCP_TASK_ST_CTX_LOCAL_COMP, 1);
}

/* Common Fastpath task init function: */
static inline void
init_rw_nvmetcp_task(struct nvmetcp_task_params *task_params,
                     enum nvmetcp_task_type task_type,
                     void *pdu_header, void *nvme_cmd,
                     struct storage_sgl_task_params *sgl_task_params)
{
        struct e5_nvmetcp_task_context *context = task_params->context;
        u32 task_size = calc_rw_task_size(task_params, task_type);
        bool slow_io = false;
        u8 num_sges = 0;

        init_default_nvmetcp_task(task_params, pdu_header, nvme_cmd, task_type);

        /* Tx/Rx: */
        if (task_params->tx_io_size) {
                /* if data to transmit: */
                init_scsi_sgl_context(&context->ystorm_st_context.state.sgl_params,
                                      &context->ystorm_st_context.state.data_desc,
                                      sgl_task_params);
                slow_io = nvmetcp_is_slow_sgl(sgl_task_params->num_sges,
                                              sgl_task_params->small_mid_sge);
                num_sges =
                        (u8)(!slow_io ? min((u32)sgl_task_params->num_sges,
                                            (u32)SCSI_NUM_SGES_SLOW_SGL_THR) :
                                            NVMETCP_WQE_NUM_SGES_SLOWIO);
                if (slow_io) {
                        SET_FIELD(context->ystorm_st_context.state.flags,
                                  YSTORM_NVMETCP_TASK_STATE_SLOW_IO, 1);
                }
        } else if (task_params->rx_io_size) {
                /* if data to receive: */
                init_scsi_sgl_context(&context->mstorm_st_context.sgl_params,
                                      &context->mstorm_st_context.data_desc,
                                      sgl_task_params);
                num_sges =
                        (u8)(!nvmetcp_is_slow_sgl(sgl_task_params->num_sges,
                                                  sgl_task_params->small_mid_sge) ?
                                                  min((u32)sgl_task_params->num_sges,
                                                      (u32)SCSI_NUM_SGES_SLOW_SGL_THR) :
                                                      NVMETCP_WQE_NUM_SGES_SLOWIO);
                context->mstorm_st_context.rem_task_size = cpu_to_le32(task_size);
        }

        /* Ustorm context: */
        init_ustorm_task_contexts(&context->ustorm_st_context,
                                  &context->ustorm_ag_context,
                                  /* Remaining Receive length is the Task Size */
                                  task_size,
                                  /* The size of the transmitted task */
                                  task_size,
                                  /* num_sges */
                                  num_sges,
                                  false);

        /* Set exp_data_acked */
        if (task_type == NVMETCP_TASK_TYPE_HOST_WRITE) {
                if (task_params->send_write_incapsule)
                        context->ustorm_ag_context.exp_data_acked = task_size;
                else
                        context->ustorm_ag_context.exp_data_acked = 0;
        } else if (task_type == NVMETCP_TASK_TYPE_HOST_READ) {
                context->ustorm_ag_context.exp_data_acked = 0;
        }

        context->ustorm_ag_context.exp_cont_len = 0;
        init_sqe(task_params, sgl_task_params, task_type);
}

static void
init_common_initiator_read_task(struct nvmetcp_task_params *task_params,
                                struct nvme_tcp_cmd_pdu *cmd_pdu_header,
                                struct nvme_command *nvme_cmd,
                                struct storage_sgl_task_params *sgl_task_params)
{
        init_rw_nvmetcp_task(task_params, NVMETCP_TASK_TYPE_HOST_READ,
                             cmd_pdu_header, nvme_cmd, sgl_task_params);
}

void init_nvmetcp_host_read_task(struct nvmetcp_task_params *task_params,
                                 struct nvme_tcp_cmd_pdu *cmd_pdu_header,
                                 struct nvme_command *nvme_cmd,
                                 struct storage_sgl_task_params *sgl_task_params)
{
        init_common_initiator_read_task(task_params, (void *)cmd_pdu_header,
                                        (void *)nvme_cmd, sgl_task_params);
}

static void
init_common_initiator_write_task(struct nvmetcp_task_params *task_params,
                                 struct nvme_tcp_cmd_pdu *cmd_pdu_header,
                                 struct nvme_command *nvme_cmd,
                                 struct storage_sgl_task_params *sgl_task_params)
{
        init_rw_nvmetcp_task(task_params, NVMETCP_TASK_TYPE_HOST_WRITE,
                             cmd_pdu_header, nvme_cmd, sgl_task_params);
}

void init_nvmetcp_host_write_task(struct nvmetcp_task_params *task_params,
                                  struct nvme_tcp_cmd_pdu *cmd_pdu_header,
                                  struct nvme_command *nvme_cmd,
                                  struct storage_sgl_task_params *sgl_task_params)
{
        init_common_initiator_write_task(task_params, (void *)cmd_pdu_header,
                                         (void *)nvme_cmd, sgl_task_params);
}

static void
init_common_login_request_task(struct nvmetcp_task_params *task_params,
                               void *login_req_pdu_header,
                               struct storage_sgl_task_params *tx_sgl_task_params,
                               struct storage_sgl_task_params *rx_sgl_task_params)
{
        struct e5_nvmetcp_task_context *context = task_params->context;

        init_default_nvmetcp_task(task_params, (void *)login_req_pdu_header, NULL,
                                  NVMETCP_TASK_TYPE_INIT_CONN_REQUEST);

        /* Ustorm Context: */
        init_ustorm_task_contexts(&context->ustorm_st_context,
                                  &context->ustorm_ag_context,

                                  /* Remaining Receive length is the Task Size */
                                  task_params->rx_io_size ?
                                  rx_sgl_task_params->total_buffer_size : 0,

                                  /* The size of the transmitted task */
                                  task_params->tx_io_size ?
                                  tx_sgl_task_params->total_buffer_size : 0,
                                  0, /* num_sges */
                                  0); /* tx_dif_conn_err_en */

        /* SGL context: */
        if (task_params->tx_io_size)
                init_scsi_sgl_context(&context->ystorm_st_context.state.sgl_params,
                                      &context->ystorm_st_context.state.data_desc,
                                      tx_sgl_task_params);
        if (task_params->rx_io_size)
                init_scsi_sgl_context(&context->mstorm_st_context.sgl_params,
                                      &context->mstorm_st_context.data_desc,
                                      rx_sgl_task_params);

        context->mstorm_st_context.rem_task_size =
                cpu_to_le32(task_params->rx_io_size ?
                                 rx_sgl_task_params->total_buffer_size : 0);
        init_sqe(task_params, tx_sgl_task_params, NVMETCP_TASK_TYPE_INIT_CONN_REQUEST);
}

/* The following function initializes Login task in Host mode: */
void init_nvmetcp_init_conn_req_task(struct nvmetcp_task_params *task_params,
                                     struct nvme_tcp_icreq_pdu *init_conn_req_pdu_hdr,
                                     struct storage_sgl_task_params *tx_sgl_task_params,
                                     struct storage_sgl_task_params *rx_sgl_task_params)
{
        init_common_login_request_task(task_params, init_conn_req_pdu_hdr,
                                       tx_sgl_task_params, rx_sgl_task_params);
}

void init_cleanup_task_nvmetcp(struct nvmetcp_task_params *task_params)
{
        init_sqe(task_params, NULL, NVMETCP_TASK_TYPE_CLEANUP);
}