isci: Convert of sci_ssp_response_iu to ssp_response_iu

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / scsi / isci / core / scic_sds_stp_request.c

/*
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 * The full GNU General Public License is included in this distribution
 * in the file called LICENSE.GPL.
 *
 * BSD LICENSE
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 * All rights reserved.
 *
 * 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.
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 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *   * Neither the name of Intel Corporation nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <scsi/sas.h>
#include "sas.h"
#include "sci_base_state.h"
#include "sci_base_state_machine.h"
#include "scic_io_request.h"
#include "scic_sds_controller.h"
#include "remote_device.h"
#include "scic_sds_request.h"
#include "scic_sds_stp_pio_request.h"
#include "scic_sds_stp_request.h"
#include "scic_sds_unsolicited_frame_control.h"
#include "sci_environment.h"
#include "sci_util.h"
#include "scu_completion_codes.h"
#include "scu_event_codes.h"
#include "scu_task_context.h"

/**
 * scic_sds_stp_request_get_h2d_reg_buffer() -
 *
 * This macro returns the address of the stp h2d reg fis buffer in the io
 * request memory
 */
#define scic_sds_stp_request_get_h2d_reg_buffer(memory) \
        ((struct host_to_dev_fis *)(\
                 ((char *)(memory)) + sizeof(struct scic_sds_stp_request) \
                 ))

/**
 * scic_sds_stp_request_get_response_buffer() -
 *
 * This macro returns the address of the ssp response iu buffer in the io
 * request memory
 */
#define scic_sds_stp_request_get_response_buffer(memory) \
        ((struct dev_to_host_fis *)(\
                 ((char *)(scic_sds_stp_request_get_h2d_reg_buffer(memory))) \
                 + sizeof(struct host_to_dev_fis) \
                 ))

/**
 * scic_sds_stp_request_get_task_context_buffer() -
 *
 * This macro returns the address of the task context buffer in the io request
 * memory
 */
#define scic_sds_stp_request_get_task_context_buffer(memory) \
        ((struct scu_task_context *)(\
                 ((char *)(scic_sds_stp_request_get_response_buffer(memory))) \
                 + SSP_RESP_IU_MAX_SIZE \
                 ))

/**
 * scic_sds_stp_request_get_sgl_element_buffer() -
 *
 * This macro returns the address of the sgl elment pairs in the io request
 * memory buffer
 */
#define scic_sds_stp_request_get_sgl_element_buffer(memory) \
        ((struct scu_sgl_element_pair *)(\
                 ((char *)(scic_sds_stp_request_get_task_context_buffer(memory))) \
                 + sizeof(struct scu_task_context) \
                 ))

/**
 *
 *
 * This method return the memory space required for STP PIO requests. u32
 */
u32 scic_sds_stp_request_get_object_size(void)
{
        return sizeof(struct scic_sds_stp_request)
               + sizeof(struct host_to_dev_fis)
               + sizeof(struct dev_to_host_fis)
               + sizeof(struct scu_task_context)
               + SMP_CACHE_BYTES
               + sizeof(struct scu_sgl_element_pair) * SCU_MAX_SGL_ELEMENT_PAIRS;
}

void scic_sds_stp_request_assign_buffers(struct scic_sds_request *sci_req)
{
        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);

        sci_req->command_buffer = scic_sds_stp_request_get_h2d_reg_buffer(stp_req);
        sci_req->response_buffer = scic_sds_stp_request_get_response_buffer(stp_req);
        sci_req->sgl_element_pair_buffer = scic_sds_stp_request_get_sgl_element_buffer(stp_req);
        sci_req->sgl_element_pair_buffer = PTR_ALIGN(sci_req->sgl_element_pair_buffer,
                                                     sizeof(struct scu_sgl_element_pair));

        if (sci_req->was_tag_assigned_by_user == false) {
                sci_req->task_context_buffer =
                        scic_sds_stp_request_get_task_context_buffer(stp_req);
                sci_req->task_context_buffer = PTR_ALIGN(sci_req->task_context_buffer,
                                                         SMP_CACHE_BYTES);
        }
}

/**
 * This method is will fill in the SCU Task Context for any type of SATA
 *    request.  This is called from the various SATA constructors.
 * @sci_req: The general IO request object which is to be used in
 *    constructing the SCU task context.
 * @task_context: The buffer pointer for the SCU task context which is being
 *    constructed.
 *
 * The general io request construction is complete. The buffer assignment for
 * the command buffer is complete. none Revisit task context construction to
 * determine what is common for SSP/SMP/STP task context structures.
 */
static void scu_sata_reqeust_construct_task_context(
        struct scic_sds_request *sds_request,
        struct scu_task_context *task_context)
{
        dma_addr_t dma_addr;
        struct scic_sds_controller *controller;
        struct scic_sds_remote_device *target_device;
        struct scic_sds_port *target_port;

        controller = scic_sds_request_get_controller(sds_request);
        target_device = scic_sds_request_get_device(sds_request);
        target_port = scic_sds_request_get_port(sds_request);

        /* Fill in the TC with the its required data */
        task_context->abort = 0;
        task_context->priority = SCU_TASK_PRIORITY_NORMAL;
        task_context->initiator_request = 1;
        task_context->connection_rate = target_device->connection_rate;
        task_context->protocol_engine_index =
                scic_sds_controller_get_protocol_engine_group(controller);
        task_context->logical_port_index =
                scic_sds_port_get_index(target_port);
        task_context->protocol_type = SCU_TASK_CONTEXT_PROTOCOL_STP;
        task_context->valid = SCU_TASK_CONTEXT_VALID;
        task_context->context_type = SCU_TASK_CONTEXT_TYPE;

        task_context->remote_node_index =
                scic_sds_remote_device_get_index(sds_request->target_device);
        task_context->command_code = 0;

        task_context->link_layer_control = 0;
        task_context->do_not_dma_ssp_good_response = 1;
        task_context->strict_ordering = 0;
        task_context->control_frame = 0;
        task_context->timeout_enable = 0;
        task_context->block_guard_enable = 0;

        task_context->address_modifier = 0;
        task_context->task_phase = 0x01;

        task_context->ssp_command_iu_length =
                (sizeof(struct host_to_dev_fis) - sizeof(u32)) / sizeof(u32);

        /* Set the first word of the H2D REG FIS */
        task_context->type.words[0] = *(u32 *)sds_request->command_buffer;

        if (sds_request->was_tag_assigned_by_user) {
                /*
                 * Build the task context now since we have already read
                 * the data
                 */
                sds_request->post_context =
                        (SCU_CONTEXT_COMMAND_REQUEST_TYPE_POST_TC |
                         (scic_sds_controller_get_protocol_engine_group(
                                                        controller) <<
                          SCU_CONTEXT_COMMAND_PROTOCOL_ENGINE_GROUP_SHIFT) |
                         (scic_sds_port_get_index(target_port) <<
                          SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT) |
                         scic_sds_io_tag_get_index(sds_request->io_tag));
        } else {
                /*
                 * Build the task context now since we have already read
                 * the data.
                 * I/O tag index is not assigned because we have to wait
                 * until we get a TCi.
                 */
                sds_request->post_context =
                        (SCU_CONTEXT_COMMAND_REQUEST_TYPE_POST_TC |
                         (scic_sds_controller_get_protocol_engine_group(
                                                        controller) <<
                          SCU_CONTEXT_COMMAND_PROTOCOL_ENGINE_GROUP_SHIFT) |
                         (scic_sds_port_get_index(target_port) <<
                          SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT));
        }

        /*
         * Copy the physical address for the command buffer to the SCU Task
         * Context. We must offset the command buffer by 4 bytes because the
         * first 4 bytes are transfered in the body of the TC.
         */
        dma_addr =
                scic_io_request_get_dma_addr(sds_request,
                                                (char *)sds_request->
                                                        command_buffer +
                                                        sizeof(u32));

        task_context->command_iu_upper = upper_32_bits(dma_addr);
        task_context->command_iu_lower = lower_32_bits(dma_addr);

        /* SATA Requests do not have a response buffer */
        task_context->response_iu_upper = 0;
        task_context->response_iu_lower = 0;
}

/**
 *
 * @sci_req:
 *
 * This method will perform any general sata request construction. What part of
 * SATA IO request construction is general? none
 */
static void scic_sds_stp_non_ncq_request_construct(
        struct scic_sds_request *sci_req)
{
        sci_req->has_started_substate_machine = true;
}

/**
 *
 * @sci_req: This parameter specifies the request to be constructed as an
 *    optimized request.
 * @optimized_task_type: This parameter specifies whether the request is to be
 *    an UDMA request or a NCQ request. - A value of 0 indicates UDMA. - A
 *    value of 1 indicates NCQ.
 *
 * This method will perform request construction common to all types of STP
 * requests that are optimized by the silicon (i.e. UDMA, NCQ). This method
 * returns an indication as to whether the construction was successful.
 */
static void scic_sds_stp_optimized_request_construct(struct scic_sds_request *sci_req,
                                                     u8 optimized_task_type,
                                                     u32 len,
                                                     enum dma_data_direction dir)
{
        struct scu_task_context *task_context = sci_req->task_context_buffer;

        /* Build the STP task context structure */
        scu_sata_reqeust_construct_task_context(sci_req, task_context);

        /* Copy over the SGL elements */
        scic_sds_request_build_sgl(sci_req);

        /* Copy over the number of bytes to be transfered */
        task_context->transfer_length_bytes = len;

        if (dir == DMA_TO_DEVICE) {
                /*
                 * The difference between the DMA IN and DMA OUT request task type
                 * values are consistent with the difference between FPDMA READ
                 * and FPDMA WRITE values.  Add the supplied task type parameter
                 * to this difference to set the task type properly for this
                 * DATA OUT (WRITE) case. */
                task_context->task_type = optimized_task_type + (SCU_TASK_TYPE_DMA_OUT
                                                                 - SCU_TASK_TYPE_DMA_IN);
        } else {
                /*
                 * For the DATA IN (READ) case, simply save the supplied
                 * optimized task type. */
                task_context->task_type = optimized_task_type;
        }
}

/**
 *
 * @sci_req: This parameter specifies the request to be constructed.
 *
 * This method will construct the STP UDMA request and its associated TC data.
 * This method returns an indication as to whether the construction was
 * successful. SCI_SUCCESS Currently this method always returns this value.
 */
enum sci_status scic_sds_stp_ncq_request_construct(struct scic_sds_request *sci_req,
                                                   u32 len,
                                                   enum dma_data_direction dir)
{
        scic_sds_stp_optimized_request_construct(sci_req,
                                                 SCU_TASK_TYPE_FPDMAQ_READ,
                                                 len, dir);
        return SCI_SUCCESS;
}

/**
 * scu_stp_raw_request_construct_task_context -
 * @sci_req: This parameter specifies the STP request object for which to
 *    construct a RAW command frame task context.
 * @task_context: This parameter specifies the SCU specific task context buffer
 *    to construct.
 *
 * This method performs the operations common to all SATA/STP requests
 * utilizing the raw frame method. none
 */
static void scu_stp_raw_request_construct_task_context(
        struct scic_sds_stp_request *sci_req,
        struct scu_task_context *task_context)
{
        scu_sata_reqeust_construct_task_context(&sci_req->parent, task_context);

        task_context->control_frame         = 0;
        task_context->priority              = SCU_TASK_PRIORITY_NORMAL;
        task_context->task_type             = SCU_TASK_TYPE_SATA_RAW_FRAME;
        task_context->type.stp.fis_type     = FIS_REGH2D;
        task_context->transfer_length_bytes =
                sizeof(struct host_to_dev_fis) - sizeof(u32);
}

void scic_stp_io_request_set_ncq_tag(
        struct scic_sds_request *req,
        u16 ncq_tag)
{
        /**
         * @note This could be made to return an error to the user if the user
         *       attempts to set the NCQ tag in the wrong state.
         */
        req->task_context_buffer->type.stp.ncq_tag = ncq_tag;
}


void *scic_stp_io_request_get_h2d_reg_address(
        struct scic_sds_request *req)
{
        return req->command_buffer;
}


void *scic_stp_io_request_get_d2h_reg_address(
        struct scic_sds_request *req)
{
        return &((struct scic_sds_stp_request *)req)->d2h_reg_fis;
}

/**
 *
 * @sci_req:
 *
 * Get the next SGL element from the request. - Check on which SGL element pair
 * we are working - if working on SLG pair element A - advance to element B -
 * else - check to see if there are more SGL element pairs for this IO request
 * - if there are more SGL element pairs - advance to the next pair and return
 * element A struct scu_sgl_element*
 */
static struct scu_sgl_element *scic_sds_stp_request_pio_get_next_sgl(struct scic_sds_stp_request *stp_req)
{
        struct scu_sgl_element *current_sgl;
        struct scic_sds_request *sci_req = &stp_req->parent;
        struct scic_sds_request_pio_sgl *pio_sgl = &stp_req->type.pio.request_current;

        if (pio_sgl->sgl_set == SCU_SGL_ELEMENT_PAIR_A) {
                if (pio_sgl->sgl_pair->B.address_lower == 0 &&
                    pio_sgl->sgl_pair->B.address_upper == 0) {
                        current_sgl = NULL;
                } else {
                        pio_sgl->sgl_set = SCU_SGL_ELEMENT_PAIR_B;
                        current_sgl = &pio_sgl->sgl_pair->B;
                }
        } else {
                if (pio_sgl->sgl_pair->next_pair_lower == 0 &&
                    pio_sgl->sgl_pair->next_pair_upper == 0) {
                        current_sgl = NULL;
                } else {
                        u64 phys_addr;

                        phys_addr = pio_sgl->sgl_pair->next_pair_upper;
                        phys_addr <<= 32;
                        phys_addr |= pio_sgl->sgl_pair->next_pair_lower;

                        pio_sgl->sgl_pair = scic_request_get_virt_addr(sci_req, phys_addr);
                        pio_sgl->sgl_set = SCU_SGL_ELEMENT_PAIR_A;
                        current_sgl = &pio_sgl->sgl_pair->A;
                }
        }

        return current_sgl;
}

/**
 *
 * @sci_req:
 * @completion_code:
 *
 * This method processes a TC completion.  The expected TC completion is for
 * the transmission of the H2D register FIS containing the SATA/STP non-data
 * request. This method always successfully processes the TC completion.
 * SCI_SUCCESS This value is always returned.
 */
static enum sci_status scic_sds_stp_request_non_data_await_h2d_tc_completion_handler(
        struct scic_sds_request *sci_req,
        u32 completion_code)
{
        switch (SCU_GET_COMPLETION_TL_STATUS(completion_code)) {
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_GOOD):
                scic_sds_request_set_status(
                        sci_req, SCU_TASK_DONE_GOOD, SCI_SUCCESS
                        );

                sci_base_state_machine_change_state(
                        &sci_req->started_substate_machine,
                        SCIC_SDS_STP_REQUEST_STARTED_NON_DATA_AWAIT_D2H_SUBSTATE
                        );
                break;

        default:
                /*
                 * All other completion status cause the IO to be complete.  If a NAK
                 * was received, then it is up to the user to retry the request. */
                scic_sds_request_set_status(
                        sci_req,
                        SCU_NORMALIZE_COMPLETION_STATUS(completion_code),
                        SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR
                        );

                sci_base_state_machine_change_state(
                        &sci_req->state_machine, SCI_BASE_REQUEST_STATE_COMPLETED);
                break;
        }

        return SCI_SUCCESS;
}

/**
 *
 * @request: This parameter specifies the request for which a frame has been
 *    received.
 * @frame_index: This parameter specifies the index of the frame that has been
 *    received.
 *
 * This method processes frames received from the target while waiting for a
 * device to host register FIS.  If a non-register FIS is received during this
 * time, it is treated as a protocol violation from an IO perspective. Indicate
 * if the received frame was processed successfully.
 */
static enum sci_status scic_sds_stp_request_non_data_await_d2h_frame_handler(
        struct scic_sds_request *sci_req,
        u32 frame_index)
{
        enum sci_status status;
        struct dev_to_host_fis *frame_header;
        u32 *frame_buffer;
        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);

        status = scic_sds_unsolicited_frame_control_get_header(
                &stp_req->parent.owning_controller->uf_control,
                frame_index,
                (void **)&frame_header);

        if (status == SCI_SUCCESS) {
                switch (frame_header->fis_type) {
                case FIS_REGD2H:
                        scic_sds_unsolicited_frame_control_get_buffer(
                                &stp_req->parent.owning_controller->uf_control,
                                frame_index,
                                (void **)&frame_buffer);

                        scic_sds_controller_copy_sata_response(
                                &stp_req->d2h_reg_fis,
                                (u32 *)frame_header,
                                frame_buffer);

                        /* The command has completed with error */
                        scic_sds_request_set_status(
                                &stp_req->parent,
                                SCU_TASK_DONE_CHECK_RESPONSE,
                                SCI_FAILURE_IO_RESPONSE_VALID);
                        break;

                default:
                        dev_warn(scic_to_dev(sci_req->owning_controller),
                                 "%s: IO Request:0x%p Frame Id:%d protocol "
                                 "violation occurred\n",
                                 __func__, stp_req, frame_index);

                        scic_sds_request_set_status(
                                &stp_req->parent,
                                SCU_TASK_DONE_UNEXP_FIS,
                                SCI_FAILURE_PROTOCOL_VIOLATION);
                        break;
                }

                sci_base_state_machine_change_state(
                        &stp_req->parent.state_machine,
                        SCI_BASE_REQUEST_STATE_COMPLETED);

                /* Frame has been decoded return it to the controller */
                scic_sds_controller_release_frame(
                        stp_req->parent.owning_controller, frame_index);
        } else
                dev_err(scic_to_dev(sci_req->owning_controller),
                        "%s: SCIC IO Request 0x%p could not get frame header "
                        "for frame index %d, status %x\n",
                        __func__, stp_req, frame_index, status);

        return status;
}

/* --------------------------------------------------------------------------- */

static const struct scic_sds_io_request_state_handler scic_sds_stp_request_started_non_data_substate_handler_table[] = {
        [SCIC_SDS_STP_REQUEST_STARTED_NON_DATA_AWAIT_H2D_COMPLETION_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .tc_completion_handler  = scic_sds_stp_request_non_data_await_h2d_tc_completion_handler,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_NON_DATA_AWAIT_D2H_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .frame_handler          = scic_sds_stp_request_non_data_await_d2h_frame_handler,
        }
};

static void scic_sds_stp_request_started_non_data_await_h2d_completion_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_non_data_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_NON_DATA_AWAIT_H2D_COMPLETION_SUBSTATE
                );

        scic_sds_remote_device_set_working_request(
                sci_req->target_device, sci_req
                );
}

static void scic_sds_stp_request_started_non_data_await_d2h_enter(void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_non_data_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_NON_DATA_AWAIT_D2H_SUBSTATE
                );
}

/* --------------------------------------------------------------------------- */

static const struct sci_base_state scic_sds_stp_request_started_non_data_substate_table[] = {
        [SCIC_SDS_STP_REQUEST_STARTED_NON_DATA_AWAIT_H2D_COMPLETION_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_non_data_await_h2d_completion_enter,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_NON_DATA_AWAIT_D2H_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_non_data_await_d2h_enter,
        },
};

enum sci_status scic_sds_stp_non_data_request_construct(struct scic_sds_request *sci_req)
{
        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);

        scic_sds_stp_non_ncq_request_construct(sci_req);

        /* Build the STP task context structure */
        scu_stp_raw_request_construct_task_context(stp_req, sci_req->task_context_buffer);

        sci_base_state_machine_construct(&sci_req->started_substate_machine,
                                         sci_req,
                                         scic_sds_stp_request_started_non_data_substate_table,
                                         SCIC_SDS_STP_REQUEST_STARTED_NON_DATA_AWAIT_H2D_COMPLETION_SUBSTATE);

        return SCI_SUCCESS;
}

#define SCU_MAX_FRAME_BUFFER_SIZE  0x400  /* 1K is the maximum SCU frame data payload */

/**
 *
 * @sci_req:
 * @length:
 *
 * This function will transmit DATA_FIS from (current sgl + offset) for input
 * parameter length. current sgl and offset is alreay stored in the IO request
 * enum sci_status
 */

static enum sci_status scic_sds_stp_request_pio_data_out_trasmit_data_frame(
        struct scic_sds_request *sci_req,
        u32 length)
{
        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);
        struct scu_sgl_element *current_sgl;

        /*
         * Recycle the TC and reconstruct it for sending out DATA FIS containing
         * for the data from current_sgl+offset for the input length */
        struct scu_task_context *task_context = scic_sds_controller_get_task_context_buffer(
                sci_req->owning_controller,
                sci_req->io_tag
                );

        if (stp_req->type.pio.request_current.sgl_set == SCU_SGL_ELEMENT_PAIR_A)
                current_sgl = &(stp_req->type.pio.request_current.sgl_pair->A);
        else
                current_sgl = &(stp_req->type.pio.request_current.sgl_pair->B);

        /* update the TC */
        task_context->command_iu_upper = current_sgl->address_upper;
        task_context->command_iu_lower = current_sgl->address_lower;
        task_context->transfer_length_bytes = length;
        task_context->type.stp.fis_type = FIS_DATA;

        /* send the new TC out. */
        return scic_controller_continue_io(sci_req);
}

/**
 *
 * @sci_req:
 *
 * enum sci_status
 */
static enum sci_status scic_sds_stp_request_pio_data_out_transmit_data(
        struct scic_sds_request *sci_req)
{

        struct scu_sgl_element *current_sgl;
        u32 sgl_offset;
        u32 remaining_bytes_in_current_sgl = 0;
        enum sci_status status = SCI_SUCCESS;

        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);

        sgl_offset = stp_req->type.pio.request_current.sgl_offset;

        if (stp_req->type.pio.request_current.sgl_set == SCU_SGL_ELEMENT_PAIR_A) {
                current_sgl = &(stp_req->type.pio.request_current.sgl_pair->A);
                remaining_bytes_in_current_sgl = stp_req->type.pio.request_current.sgl_pair->A.length - sgl_offset;
        } else {
                current_sgl = &(stp_req->type.pio.request_current.sgl_pair->B);
                remaining_bytes_in_current_sgl = stp_req->type.pio.request_current.sgl_pair->B.length - sgl_offset;
        }


        if (stp_req->type.pio.pio_transfer_bytes > 0) {
                if (stp_req->type.pio.pio_transfer_bytes >= remaining_bytes_in_current_sgl) {
                        /* recycle the TC and send the H2D Data FIS from (current sgl + sgl_offset) and length = remaining_bytes_in_current_sgl */
                        status = scic_sds_stp_request_pio_data_out_trasmit_data_frame(sci_req, remaining_bytes_in_current_sgl);
                        if (status == SCI_SUCCESS) {
                                stp_req->type.pio.pio_transfer_bytes -= remaining_bytes_in_current_sgl;

                                /* update the current sgl, sgl_offset and save for future */
                                current_sgl = scic_sds_stp_request_pio_get_next_sgl(stp_req);
                                sgl_offset = 0;
                        }
                } else if (stp_req->type.pio.pio_transfer_bytes < remaining_bytes_in_current_sgl) {
                        /* recycle the TC and send the H2D Data FIS from (current sgl + sgl_offset) and length = type.pio.pio_transfer_bytes */
                        scic_sds_stp_request_pio_data_out_trasmit_data_frame(sci_req, stp_req->type.pio.pio_transfer_bytes);

                        if (status == SCI_SUCCESS) {
                                /* Sgl offset will be adjusted and saved for future */
                                sgl_offset += stp_req->type.pio.pio_transfer_bytes;
                                current_sgl->address_lower += stp_req->type.pio.pio_transfer_bytes;
                                stp_req->type.pio.pio_transfer_bytes = 0;
                        }
                }
        }

        if (status == SCI_SUCCESS) {
                stp_req->type.pio.request_current.sgl_offset = sgl_offset;
        }

        return status;
}

/**
 *
 * @stp_request: The request that is used for the SGL processing.
 * @data_buffer: The buffer of data to be copied.
 * @length: The length of the data transfer.
 *
 * Copy the data from the buffer for the length specified to the IO reqeust SGL
 * specified data region. enum sci_status
 */
static enum sci_status
scic_sds_stp_request_pio_data_in_copy_data_buffer(struct scic_sds_stp_request *stp_req,
                                                  u8 *data_buf, u32 len)
{
        struct scic_sds_request *sci_req;
        struct isci_request *ireq;
        u8 *src_addr;
        int copy_len;
        struct sas_task *task;
        struct scatterlist *sg;
        void *kaddr;
        int total_len = len;

        sci_req = &stp_req->parent;
        ireq = scic_sds_request_get_user_request(sci_req);
        task = isci_request_access_task(ireq);
        src_addr = data_buf;

        if (task->num_scatter > 0) {
                sg = task->scatter;

                while (total_len > 0) {
                        struct page *page = sg_page(sg);

                        copy_len = min_t(int, total_len, sg_dma_len(sg));
                        kaddr = kmap_atomic(page, KM_IRQ0);
                        memcpy(kaddr + sg->offset, src_addr, copy_len);
                        kunmap_atomic(kaddr, KM_IRQ0);
                        total_len -= copy_len;
                        src_addr += copy_len;
                        sg = sg_next(sg);
                }
        } else {
                BUG_ON(task->total_xfer_len < total_len);
                memcpy(task->scatter, src_addr, total_len);
        }

        return SCI_SUCCESS;
}

/**
 *
 * @sci_req: The PIO DATA IN request that is to receive the data.
 * @data_buffer: The buffer to copy from.
 *
 * Copy the data buffer to the io request data region. enum sci_status
 */
static enum sci_status scic_sds_stp_request_pio_data_in_copy_data(
        struct scic_sds_stp_request *sci_req,
        u8 *data_buffer)
{
        enum sci_status status;

        /*
         * If there is less than 1K remaining in the transfer request
         * copy just the data for the transfer */
        if (sci_req->type.pio.pio_transfer_bytes < SCU_MAX_FRAME_BUFFER_SIZE) {
                status = scic_sds_stp_request_pio_data_in_copy_data_buffer(
                        sci_req, data_buffer, sci_req->type.pio.pio_transfer_bytes);

                if (status == SCI_SUCCESS)
                        sci_req->type.pio.pio_transfer_bytes = 0;
        } else {
                /* We are transfering the whole frame so copy */
                status = scic_sds_stp_request_pio_data_in_copy_data_buffer(
                        sci_req, data_buffer, SCU_MAX_FRAME_BUFFER_SIZE);

                if (status == SCI_SUCCESS)
                        sci_req->type.pio.pio_transfer_bytes -= SCU_MAX_FRAME_BUFFER_SIZE;
        }

        return status;
}

/**
 *
 * @sci_req:
 * @completion_code:
 *
 * enum sci_status
 */
static enum sci_status scic_sds_stp_request_pio_await_h2d_completion_tc_completion_handler(
        struct scic_sds_request *sci_req,
        u32 completion_code)
{
        enum sci_status status = SCI_SUCCESS;

        switch (SCU_GET_COMPLETION_TL_STATUS(completion_code)) {
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_GOOD):
                scic_sds_request_set_status(
                        sci_req, SCU_TASK_DONE_GOOD, SCI_SUCCESS
                        );

                sci_base_state_machine_change_state(
                        &sci_req->started_substate_machine,
                        SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_FRAME_SUBSTATE
                        );
                break;

        default:
                /*
                 * All other completion status cause the IO to be complete.  If a NAK
                 * was received, then it is up to the user to retry the request. */
                scic_sds_request_set_status(
                        sci_req,
                        SCU_NORMALIZE_COMPLETION_STATUS(completion_code),
                        SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR
                        );

                sci_base_state_machine_change_state(
                        &sci_req->state_machine,
                        SCI_BASE_REQUEST_STATE_COMPLETED
                        );
                break;
        }

        return status;
}

/**
 *
 * @sci_req:
 * @frame_index:
 *
 * enum sci_status
 */
static enum sci_status scic_sds_stp_request_pio_await_frame_frame_handler(
        struct scic_sds_request *sci_req,
        u32 frame_index)
{
        enum sci_status status;
        struct dev_to_host_fis *frame_header;
        u32 *frame_buffer;
        struct scic_sds_stp_request *stp_req = container_of(sci_req, typeof(*stp_req), parent);
        struct isci_request *ireq = sci_req->ireq;
        struct sas_task *task = isci_request_access_task(ireq);

        status = scic_sds_unsolicited_frame_control_get_header(
                &(stp_req->parent.owning_controller->uf_control),
                frame_index,
                (void **)&frame_header);

        if (status == SCI_SUCCESS) {
                switch (frame_header->fis_type) {
                case FIS_PIO_SETUP:
                        /* Get from the frame buffer the PIO Setup Data */
                        scic_sds_unsolicited_frame_control_get_buffer(
                                &(stp_req->parent.owning_controller->uf_control),
                                frame_index,
                                (void **)&frame_buffer);

                        /* Get the data from the PIO Setup The SCU Hardware
                         * returns first word in the frame_header and the rest
                         * of the data is in the frame buffer so we need to back
                         * up one dword
                         */

                        /* transfer_count: first 16bits in the 4th dword */
                        stp_req->type.pio.pio_transfer_bytes =
                                frame_buffer[3] & 0xffff;

                        /* ending_status: 4th byte in the 3rd dword */
                        stp_req->type.pio.ending_status =
                                (frame_buffer[2] >> 24) & 0xff;

                        scic_sds_controller_copy_sata_response(
                                &stp_req->d2h_reg_fis,
                                (u32 *)frame_header,
                                frame_buffer);

                        stp_req->d2h_reg_fis.status =
                                stp_req->type.pio.ending_status;

                        /* The next state is dependent on whether the
                         * request was PIO Data-in or Data out
                         */
                        if (task->data_dir == DMA_FROM_DEVICE) {
                                sci_base_state_machine_change_state(
                                        &stp_req->parent.started_substate_machine,
                                        SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_IN_AWAIT_DATA_SUBSTATE);
                        } else if (task->data_dir == DMA_TO_DEVICE) {
                                /* Transmit data */
                                status = scic_sds_stp_request_pio_data_out_transmit_data(sci_req);
                                if (status == SCI_SUCCESS) {
                                        sci_base_state_machine_change_state(
                                                &stp_req->parent.started_substate_machine,
                                                SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_OUT_TRANSMIT_DATA_SUBSTATE);
                                }
                        }
                        break;

                case FIS_SETDEVBITS:
                        sci_base_state_machine_change_state(
                                &stp_req->parent.started_substate_machine,
                                SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_FRAME_SUBSTATE);
                        break;

                case FIS_REGD2H:
                        if ((frame_header->status & ATA_BUSY) == 0) {
                                scic_sds_unsolicited_frame_control_get_buffer(
                                        &(stp_req->parent.owning_controller->uf_control),
                                        frame_index,
                                        (void **)&frame_buffer);

                                scic_sds_controller_copy_sata_response(
                                        &stp_req->d2h_reg_fis,
                                        (u32 *)frame_header,
                                        frame_buffer);

                                scic_sds_request_set_status(
                                        &stp_req->parent,
                                        SCU_TASK_DONE_CHECK_RESPONSE,
                                        SCI_FAILURE_IO_RESPONSE_VALID);

                                sci_base_state_machine_change_state(
                                        &stp_req->parent.state_machine,
                                        SCI_BASE_REQUEST_STATE_COMPLETED);
                        } else {
                                /* Now why is the drive sending a D2H Register
                                 * FIS when it is still busy?
                                 * Do nothing since we are still in the right
                                 * state.
                                 */
                                dev_dbg(scic_to_dev(sci_req->owning_controller),
                                        "%s: SCIC PIO Request 0x%p received "
                                        "D2H Register FIS with BSY status "
                                        "0x%x\n",
                                        __func__,
                                        stp_req,
                                        frame_header->status);
                        }
                        break;

                default:
                        /* FIXME: what do we do here? */
                        break;
                }

                /* Frame is decoded return it to the controller */
                scic_sds_controller_release_frame(
                        stp_req->parent.owning_controller,
                        frame_index);
        } else
                dev_err(scic_to_dev(sci_req->owning_controller),
                        "%s: SCIC IO Request 0x%p could not get frame header "
                        "for frame index %d, status %x\n",
                        __func__, stp_req, frame_index, status);

        return status;
}

/**
 *
 * @sci_req:
 * @frame_index:
 *
 * enum sci_status
 */
static enum sci_status scic_sds_stp_request_pio_data_in_await_data_frame_handler(
        struct scic_sds_request *sci_req,
        u32 frame_index)
{
        enum sci_status status;
        struct dev_to_host_fis *frame_header;
        struct sata_fis_data *frame_buffer;
        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);

        status = scic_sds_unsolicited_frame_control_get_header(
                &(stp_req->parent.owning_controller->uf_control),
                frame_index,
                (void **)&frame_header);

        if (status == SCI_SUCCESS) {
                if (frame_header->fis_type == FIS_DATA) {
                        if (stp_req->type.pio.request_current.sgl_pair ==
                                        NULL) {
                                stp_req->parent.saved_rx_frame_index =
                                        frame_index;
                                stp_req->type.pio.pio_transfer_bytes = 0;
                        } else {
                                status = scic_sds_unsolicited_frame_control_get_buffer(
                                        &(stp_req->parent.owning_controller->uf_control),
                                        frame_index,
                                        (void **)&frame_buffer);

                                status = scic_sds_stp_request_pio_data_in_copy_data(
                                                stp_req,
                                                (u8 *)frame_buffer);

                                /* Frame is decoded return it to the controller */
                                scic_sds_controller_release_frame(
                                        stp_req->parent.owning_controller,
                                        frame_index);
                        }

                        /*
                         * Check for the end of the transfer, are there more
                         * bytes remaining for this data transfer
                         */
                        if ((status == SCI_SUCCESS) &&
                            (stp_req->type.pio.pio_transfer_bytes == 0)) {
                                if ((stp_req->type.pio.ending_status &
                                                        ATA_BUSY) == 0) {
                                        scic_sds_request_set_status(
                                                &stp_req->parent,
                                                SCU_TASK_DONE_CHECK_RESPONSE,
                                                SCI_FAILURE_IO_RESPONSE_VALID);

                                        sci_base_state_machine_change_state(
                                                &stp_req->parent.state_machine,
                                                SCI_BASE_REQUEST_STATE_COMPLETED);
                                } else {
                                        sci_base_state_machine_change_state(
                                                &sci_req->started_substate_machine,
                                                SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_FRAME_SUBSTATE);
                                }
                        }
                } else {
                        dev_err(scic_to_dev(sci_req->owning_controller),
                                "%s: SCIC PIO Request 0x%p received frame %d "
                                "with fis type 0x%02x when expecting a data "
                                "fis.\n",
                                __func__,
                                stp_req,
                                frame_index,
                                frame_header->fis_type);

                        scic_sds_request_set_status(
                                &stp_req->parent,
                                SCU_TASK_DONE_GOOD,
                                SCI_FAILURE_IO_REQUIRES_SCSI_ABORT);

                        sci_base_state_machine_change_state(
                                &stp_req->parent.state_machine,
                                SCI_BASE_REQUEST_STATE_COMPLETED);

                        /* Frame is decoded return it to the controller */
                        scic_sds_controller_release_frame(
                                stp_req->parent.owning_controller,
                                frame_index);
                }
        } else
                dev_err(scic_to_dev(sci_req->owning_controller),
                        "%s: SCIC IO Request 0x%p could not get frame header "
                        "for frame index %d, status %x\n",
                        __func__, stp_req, frame_index, status);

        return status;
}


/**
 *
 * @sci_req:
 * @completion_code:
 *
 * enum sci_status
 */
static enum sci_status scic_sds_stp_request_pio_data_out_await_data_transmit_completion_tc_completion_handler(

        struct scic_sds_request *sci_req,
        u32 completion_code)
{
        enum sci_status status = SCI_SUCCESS;
        bool all_frames_transferred = false;
        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);

        switch (SCU_GET_COMPLETION_TL_STATUS(completion_code)) {
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_GOOD):
                /* Transmit data */
                if (stp_req->type.pio.pio_transfer_bytes != 0) {
                        status = scic_sds_stp_request_pio_data_out_transmit_data(sci_req);
                        if (status == SCI_SUCCESS) {
                                if (stp_req->type.pio.pio_transfer_bytes == 0)
                                        all_frames_transferred = true;
                        }
                } else if (stp_req->type.pio.pio_transfer_bytes == 0) {
                        /*
                         * this will happen if the all data is written at the
                         * first time after the pio setup fis is received
                         */
                        all_frames_transferred  = true;
                }

                /* all data transferred. */
                if (all_frames_transferred) {
                        /*
                         * Change the state to SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_IN_AWAIT_FRAME_SUBSTATE
                         * and wait for PIO_SETUP fis / or D2H REg fis. */
                        sci_base_state_machine_change_state(
                                &sci_req->started_substate_machine,
                                SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_FRAME_SUBSTATE
                                );
                }
                break;

        default:
                /*
                 * All other completion status cause the IO to be complete.  If a NAK
                 * was received, then it is up to the user to retry the request. */
                scic_sds_request_set_status(
                        sci_req,
                        SCU_NORMALIZE_COMPLETION_STATUS(completion_code),
                        SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR
                        );

                sci_base_state_machine_change_state(
                        &sci_req->state_machine,
                        SCI_BASE_REQUEST_STATE_COMPLETED
                        );
                break;
        }

        return status;
}

/**
 *
 * @request: This is the request which is receiving the event.
 * @event_code: This is the event code that the request on which the request is
 *    expected to take action.
 *
 * This method will handle any link layer events while waiting for the data
 * frame. enum sci_status SCI_SUCCESS SCI_FAILURE
 */
static enum sci_status scic_sds_stp_request_pio_data_in_await_data_event_handler(
        struct scic_sds_request *request,
        u32 event_code)
{
        enum sci_status status;

        switch (scu_get_event_specifier(event_code)) {
        case SCU_TASK_DONE_CRC_ERR << SCU_EVENT_SPECIFIC_CODE_SHIFT:
                /*
                 * We are waiting for data and the SCU has R_ERR the data frame.
                 * Go back to waiting for the D2H Register FIS */
                sci_base_state_machine_change_state(
                        &request->started_substate_machine,
                        SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_FRAME_SUBSTATE
                        );

                status = SCI_SUCCESS;
                break;

        default:
                dev_err(scic_to_dev(request->owning_controller),
                        "%s: SCIC PIO Request 0x%p received unexpected "
                        "event 0x%08x\n",
                        __func__, request, event_code);

                /* / @todo Should we fail the PIO request when we get an unexpected event? */
                status = SCI_FAILURE;
                break;
        }

        return status;
}

/* --------------------------------------------------------------------------- */

static const struct scic_sds_io_request_state_handler scic_sds_stp_request_started_pio_substate_handler_table[] = {
        [SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_H2D_COMPLETION_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .tc_completion_handler  = scic_sds_stp_request_pio_await_h2d_completion_tc_completion_handler,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_FRAME_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .frame_handler          = scic_sds_stp_request_pio_await_frame_frame_handler
        },
        [SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_IN_AWAIT_DATA_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .event_handler          = scic_sds_stp_request_pio_data_in_await_data_event_handler,
                .frame_handler          = scic_sds_stp_request_pio_data_in_await_data_frame_handler
        },
        [SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_OUT_TRANSMIT_DATA_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .tc_completion_handler  = scic_sds_stp_request_pio_data_out_await_data_transmit_completion_tc_completion_handler,
        }
};

static void scic_sds_stp_request_started_pio_await_h2d_completion_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_pio_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_H2D_COMPLETION_SUBSTATE
                );

        scic_sds_remote_device_set_working_request(
                sci_req->target_device, sci_req);
}

static void scic_sds_stp_request_started_pio_await_frame_enter(void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_pio_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_FRAME_SUBSTATE
                );
}

static void scic_sds_stp_request_started_pio_data_in_await_data_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_pio_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_IN_AWAIT_DATA_SUBSTATE
                );
}

static void scic_sds_stp_request_started_pio_data_out_transmit_data_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_pio_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_OUT_TRANSMIT_DATA_SUBSTATE
                );
}

/* --------------------------------------------------------------------------- */

static const struct sci_base_state scic_sds_stp_request_started_pio_substate_table[] = {
        [SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_H2D_COMPLETION_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_pio_await_h2d_completion_enter,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_FRAME_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_pio_await_frame_enter,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_IN_AWAIT_DATA_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_pio_data_in_await_data_enter,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_PIO_DATA_OUT_TRANSMIT_DATA_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_pio_data_out_transmit_data_enter,
        }
};

enum sci_status
scic_sds_stp_pio_request_construct(struct scic_sds_request *sci_req,
                                   bool copy_rx_frame)
{
        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);
        struct scic_sds_stp_pio_request *pio = &stp_req->type.pio;

        scic_sds_stp_non_ncq_request_construct(sci_req);

        scu_stp_raw_request_construct_task_context(stp_req,
                                                   sci_req->task_context_buffer);

        pio->current_transfer_bytes = 0;
        pio->ending_error = 0;
        pio->ending_status = 0;

        pio->request_current.sgl_offset = 0;
        pio->request_current.sgl_set = SCU_SGL_ELEMENT_PAIR_A;

        if (copy_rx_frame) {
                scic_sds_request_build_sgl(sci_req);
                /* Since the IO request copy of the TC contains the same data as
                 * the actual TC this pointer is vaild for either.
                 */
                pio->request_current.sgl_pair = &sci_req->task_context_buffer->sgl_pair_ab;
        } else {
                /* The user does not want the data copied to the SGL buffer location */
                pio->request_current.sgl_pair = NULL;
        }

        sci_base_state_machine_construct(&sci_req->started_substate_machine,
                                         sci_req,
                                         scic_sds_stp_request_started_pio_substate_table,
                                         SCIC_SDS_STP_REQUEST_STARTED_PIO_AWAIT_H2D_COMPLETION_SUBSTATE);

        return SCI_SUCCESS;
}

static void scic_sds_stp_request_udma_complete_request(
        struct scic_sds_request *request,
        u32 scu_status,
        enum sci_status sci_status)
{
        scic_sds_request_set_status(request, scu_status, sci_status);
        sci_base_state_machine_change_state(&request->state_machine,
                SCI_BASE_REQUEST_STATE_COMPLETED);
}

/**
 *
 * @sci_req:
 * @frame_index:
 *
 * enum sci_status
 */
static enum sci_status scic_sds_stp_request_udma_general_frame_handler(
        struct scic_sds_request *sci_req,
        u32 frame_index)
{
        enum sci_status status;
        struct dev_to_host_fis *frame_header;
        u32 *frame_buffer;

        status = scic_sds_unsolicited_frame_control_get_header(
                &sci_req->owning_controller->uf_control,
                frame_index,
                (void **)&frame_header);

        if ((status == SCI_SUCCESS) &&
            (frame_header->fis_type == FIS_REGD2H)) {
                scic_sds_unsolicited_frame_control_get_buffer(
                        &sci_req->owning_controller->uf_control,
                        frame_index,
                        (void **)&frame_buffer);

                scic_sds_controller_copy_sata_response(
                        &((struct scic_sds_stp_request *)sci_req)->d2h_reg_fis,
                        (u32 *)frame_header,
                        frame_buffer);
        }

        scic_sds_controller_release_frame(
                sci_req->owning_controller, frame_index);

        return status;
}

/**
 * This method process TC completions while in the state where we are waiting
 *    for TC completions.
 * @sci_req:
 * @completion_code:
 *
 * enum sci_status
 */
static enum sci_status scic_sds_stp_request_udma_await_tc_completion_tc_completion_handler(
        struct scic_sds_request *request,
        u32 completion_code)
{
        enum sci_status status = SCI_SUCCESS;
        struct scic_sds_stp_request *sci_req = (struct scic_sds_stp_request *)request;

        switch (SCU_GET_COMPLETION_TL_STATUS(completion_code)) {
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_GOOD):
                scic_sds_stp_request_udma_complete_request(
                        &sci_req->parent, SCU_TASK_DONE_GOOD, SCI_SUCCESS
                        );
                break;

        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_UNEXP_FIS):
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_REG_ERR):
                /*
                 * We must check ther response buffer to see if the D2H Register FIS was
                 * received before we got the TC completion. */
                if (sci_req->d2h_reg_fis.fis_type == FIS_REGD2H) {
                        scic_sds_remote_device_suspend(
                                sci_req->parent.target_device,
                                SCU_EVENT_SPECIFIC(SCU_NORMALIZE_COMPLETION_STATUS(completion_code))
                                );

                        scic_sds_stp_request_udma_complete_request(
                                &sci_req->parent,
                                SCU_TASK_DONE_CHECK_RESPONSE,
                                SCI_FAILURE_IO_RESPONSE_VALID
                                );
                } else {
                        /*
                         * If we have an error completion status for the TC then we can expect a
                         * D2H register FIS from the device so we must change state to wait for it */
                        sci_base_state_machine_change_state(
                                &sci_req->parent.started_substate_machine,
                                SCIC_SDS_STP_REQUEST_STARTED_UDMA_AWAIT_D2H_REG_FIS_SUBSTATE
                                );
                }
                break;

        /*
         * / @todo Check to see if any of these completion status need to wait for
         * /       the device to host register fis. */
        /* / @todo We can retry the command for SCU_TASK_DONE_CMD_LL_R_ERR - this comes only for B0 */
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_INV_FIS_LEN):
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_MAX_PLD_ERR):
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_LL_R_ERR):
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_CMD_LL_R_ERR):
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_CRC_ERR):
                scic_sds_remote_device_suspend(
                        sci_req->parent.target_device,
                        SCU_EVENT_SPECIFIC(SCU_NORMALIZE_COMPLETION_STATUS(completion_code))
                        );
        /* Fall through to the default case */
        default:
                /* All other completion status cause the IO to be complete. */
                scic_sds_stp_request_udma_complete_request(
                        &sci_req->parent,
                        SCU_NORMALIZE_COMPLETION_STATUS(completion_code),
                        SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR
                        );
                break;
        }

        return status;
}

static enum sci_status scic_sds_stp_request_udma_await_d2h_reg_fis_frame_handler(
        struct scic_sds_request *sci_req,
        u32 frame_index)
{
        enum sci_status status;

        /* Use the general frame handler to copy the resposne data */
        status = scic_sds_stp_request_udma_general_frame_handler(sci_req, frame_index);

        if (status == SCI_SUCCESS) {
                scic_sds_stp_request_udma_complete_request(
                        sci_req,
                        SCU_TASK_DONE_CHECK_RESPONSE,
                        SCI_FAILURE_IO_RESPONSE_VALID
                        );
        }

        return status;
}

/* --------------------------------------------------------------------------- */

static const struct scic_sds_io_request_state_handler scic_sds_stp_request_started_udma_substate_handler_table[] = {
        [SCIC_SDS_STP_REQUEST_STARTED_UDMA_AWAIT_TC_COMPLETION_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .tc_completion_handler  = scic_sds_stp_request_udma_await_tc_completion_tc_completion_handler,
                .frame_handler          = scic_sds_stp_request_udma_general_frame_handler,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_UDMA_AWAIT_D2H_REG_FIS_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .frame_handler          = scic_sds_stp_request_udma_await_d2h_reg_fis_frame_handler,
        },
};

static void scic_sds_stp_request_started_udma_await_tc_completion_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_udma_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_UDMA_AWAIT_TC_COMPLETION_SUBSTATE
                );
}

/**
 *
 *
 * This state is entered when there is an TC completion failure.  The hardware
 * received an unexpected condition while processing the IO request and now
 * will UF the D2H register FIS to complete the IO.
 */
static void scic_sds_stp_request_started_udma_await_d2h_reg_fis_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_udma_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_UDMA_AWAIT_D2H_REG_FIS_SUBSTATE
                );
}

/* --------------------------------------------------------------------------- */

static const struct sci_base_state scic_sds_stp_request_started_udma_substate_table[] = {
        [SCIC_SDS_STP_REQUEST_STARTED_UDMA_AWAIT_TC_COMPLETION_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_udma_await_tc_completion_enter,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_UDMA_AWAIT_D2H_REG_FIS_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_udma_await_d2h_reg_fis_enter,
        },
};

enum sci_status scic_sds_stp_udma_request_construct(struct scic_sds_request *sci_req,
                                                    u32 len,
                                                    enum dma_data_direction dir)
{
        scic_sds_stp_non_ncq_request_construct(sci_req);

        scic_sds_stp_optimized_request_construct(sci_req, SCU_TASK_TYPE_DMA_IN,
                                                 len, dir);

        sci_base_state_machine_construct(
                &sci_req->started_substate_machine,
                sci_req,
                scic_sds_stp_request_started_udma_substate_table,
                SCIC_SDS_STP_REQUEST_STARTED_UDMA_AWAIT_TC_COMPLETION_SUBSTATE
                );

        return SCI_SUCCESS;
}

/**
 *
 * @sci_req:
 * @completion_code:
 *
 * This method processes a TC completion.  The expected TC completion is for
 * the transmission of the H2D register FIS containing the SATA/STP non-data
 * request. This method always successfully processes the TC completion.
 * SCI_SUCCESS This value is always returned.
 */
static enum sci_status scic_sds_stp_request_soft_reset_await_h2d_asserted_tc_completion_handler(
        struct scic_sds_request *sci_req,
        u32 completion_code)
{
        switch (SCU_GET_COMPLETION_TL_STATUS(completion_code)) {
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_GOOD):
                scic_sds_request_set_status(
                        sci_req, SCU_TASK_DONE_GOOD, SCI_SUCCESS
                        );

                sci_base_state_machine_change_state(
                        &sci_req->started_substate_machine,
                        SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_H2D_DIAGNOSTIC_COMPLETION_SUBSTATE
                        );
                break;

        default:
                /*
                 * All other completion status cause the IO to be complete.  If a NAK
                 * was received, then it is up to the user to retry the request. */
                scic_sds_request_set_status(
                        sci_req,
                        SCU_NORMALIZE_COMPLETION_STATUS(completion_code),
                        SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR
                        );

                sci_base_state_machine_change_state(
                        &sci_req->state_machine, SCI_BASE_REQUEST_STATE_COMPLETED);
                break;
        }

        return SCI_SUCCESS;
}

/**
 *
 * @sci_req:
 * @completion_code:
 *
 * This method processes a TC completion.  The expected TC completion is for
 * the transmission of the H2D register FIS containing the SATA/STP non-data
 * request. This method always successfully processes the TC completion.
 * SCI_SUCCESS This value is always returned.
 */
static enum sci_status scic_sds_stp_request_soft_reset_await_h2d_diagnostic_tc_completion_handler(
        struct scic_sds_request *sci_req,
        u32 completion_code)
{
        switch (SCU_GET_COMPLETION_TL_STATUS(completion_code)) {
        case SCU_MAKE_COMPLETION_STATUS(SCU_TASK_DONE_GOOD):
                scic_sds_request_set_status(
                        sci_req, SCU_TASK_DONE_GOOD, SCI_SUCCESS
                        );

                sci_base_state_machine_change_state(
                        &sci_req->started_substate_machine,
                        SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_D2H_RESPONSE_FRAME_SUBSTATE
                        );
                break;

        default:
                /*
                 * All other completion status cause the IO to be complete.  If a NAK
                 * was received, then it is up to the user to retry the request. */
                scic_sds_request_set_status(
                        sci_req,
                        SCU_NORMALIZE_COMPLETION_STATUS(completion_code),
                        SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR
                        );

                sci_base_state_machine_change_state(&sci_req->state_machine,
                                SCI_BASE_REQUEST_STATE_COMPLETED);
                break;
        }

        return SCI_SUCCESS;
}

/**
 *
 * @request: This parameter specifies the request for which a frame has been
 *    received.
 * @frame_index: This parameter specifies the index of the frame that has been
 *    received.
 *
 * This method processes frames received from the target while waiting for a
 * device to host register FIS.  If a non-register FIS is received during this
 * time, it is treated as a protocol violation from an IO perspective. Indicate
 * if the received frame was processed successfully.
 */
static enum sci_status scic_sds_stp_request_soft_reset_await_d2h_frame_handler(
        struct scic_sds_request *request,
        u32 frame_index)
{
        enum sci_status status;
        struct dev_to_host_fis *frame_header;
        u32 *frame_buffer;
        struct scic_sds_stp_request *stp_req =
                (struct scic_sds_stp_request *)request;

        status = scic_sds_unsolicited_frame_control_get_header(
                &(stp_req->parent.owning_controller->uf_control),
                frame_index,
                (void **)&frame_header);

        if (status == SCI_SUCCESS) {
                switch (frame_header->fis_type) {
                case FIS_REGD2H:
                        scic_sds_unsolicited_frame_control_get_buffer(
                                &(stp_req->parent.owning_controller->uf_control),
                                frame_index,
                                (void **)&frame_buffer);

                        scic_sds_controller_copy_sata_response(
                                &stp_req->d2h_reg_fis,
                                (u32 *)frame_header,
                                frame_buffer);

                        /* The command has completed with error */
                        scic_sds_request_set_status(
                                &stp_req->parent,
                                SCU_TASK_DONE_CHECK_RESPONSE,
                                SCI_FAILURE_IO_RESPONSE_VALID);
                        break;

                default:
                        dev_warn(scic_to_dev(request->owning_controller),
                                 "%s: IO Request:0x%p Frame Id:%d protocol "
                                 "violation occurred\n",
                                 __func__,
                                 stp_req,
                                 frame_index);

                        scic_sds_request_set_status(
                                &stp_req->parent,
                                SCU_TASK_DONE_UNEXP_FIS,
                                SCI_FAILURE_PROTOCOL_VIOLATION);
                        break;
                }

                sci_base_state_machine_change_state(
                        &stp_req->parent.state_machine,
                        SCI_BASE_REQUEST_STATE_COMPLETED);

                /* Frame has been decoded return it to the controller */
                scic_sds_controller_release_frame(
                        stp_req->parent.owning_controller, frame_index);
        } else
                dev_err(scic_to_dev(request->owning_controller),
                        "%s: SCIC IO Request 0x%p could not get frame header "
                        "for frame index %d, status %x\n",
                        __func__, stp_req, frame_index, status);

        return status;
}

/* --------------------------------------------------------------------------- */

static const struct scic_sds_io_request_state_handler scic_sds_stp_request_started_soft_reset_substate_handler_table[] = {
        [SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_H2D_ASSERTED_COMPLETION_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .tc_completion_handler  = scic_sds_stp_request_soft_reset_await_h2d_asserted_tc_completion_handler,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_H2D_DIAGNOSTIC_COMPLETION_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .tc_completion_handler  = scic_sds_stp_request_soft_reset_await_h2d_diagnostic_tc_completion_handler,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_D2H_RESPONSE_FRAME_SUBSTATE] = {
                .abort_handler          = scic_sds_request_started_state_abort_handler,
                .frame_handler          = scic_sds_stp_request_soft_reset_await_d2h_frame_handler,
        },
};

static void scic_sds_stp_request_started_soft_reset_await_h2d_asserted_completion_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_soft_reset_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_H2D_ASSERTED_COMPLETION_SUBSTATE
                );

        scic_sds_remote_device_set_working_request(
                sci_req->target_device, sci_req
                );
}

static void scic_sds_stp_request_started_soft_reset_await_h2d_diagnostic_completion_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;
        struct scu_task_context *task_context;
        struct host_to_dev_fis *h2d_fis;
        enum sci_status status;

        /* Clear the SRST bit */
        h2d_fis = scic_stp_io_request_get_h2d_reg_address(sci_req);
        h2d_fis->control = 0;

        /* Clear the TC control bit */
        task_context = scic_sds_controller_get_task_context_buffer(
                sci_req->owning_controller, sci_req->io_tag);
        task_context->control_frame = 0;

        status = scic_controller_continue_io(sci_req);
        if (status == SCI_SUCCESS) {
                SET_STATE_HANDLER(
                        sci_req,
                        scic_sds_stp_request_started_soft_reset_substate_handler_table,
                        SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_H2D_DIAGNOSTIC_COMPLETION_SUBSTATE
                        );
        }
}

static void scic_sds_stp_request_started_soft_reset_await_d2h_response_enter(
        void *object)
{
        struct scic_sds_request *sci_req = object;

        SET_STATE_HANDLER(
                sci_req,
                scic_sds_stp_request_started_soft_reset_substate_handler_table,
                SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_D2H_RESPONSE_FRAME_SUBSTATE
                );
}

static const struct sci_base_state scic_sds_stp_request_started_soft_reset_substate_table[] = {
        [SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_H2D_ASSERTED_COMPLETION_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_soft_reset_await_h2d_asserted_completion_enter,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_H2D_DIAGNOSTIC_COMPLETION_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_soft_reset_await_h2d_diagnostic_completion_enter,
        },
        [SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_D2H_RESPONSE_FRAME_SUBSTATE] = {
                .enter_state = scic_sds_stp_request_started_soft_reset_await_d2h_response_enter,
        },
};

enum sci_status scic_sds_stp_soft_reset_request_construct(struct scic_sds_request *sci_req)
{
        struct scic_sds_stp_request *stp_req =
                container_of(sci_req, typeof(*stp_req), parent);

        scic_sds_stp_non_ncq_request_construct(sci_req);

        /* Build the STP task context structure */
        scu_stp_raw_request_construct_task_context(stp_req, sci_req->task_context_buffer);

        sci_base_state_machine_construct(&sci_req->started_substate_machine,
                                         sci_req,
                                         scic_sds_stp_request_started_soft_reset_substate_table,
                                         SCIC_SDS_STP_REQUEST_STARTED_SOFT_RESET_AWAIT_H2D_ASSERTED_COMPLETION_SUBSTATE);

        return SCI_SUCCESS;
}