/*
 *  linux/drivers/scsi/esas2r/esas2r_init.c
 *      For use with ATTO ExpressSAS R6xx SAS/SATA RAID controllers
 *
 *  Copyright (c) 2001-2013 ATTO Technology, Inc.
 *  (mailto:linuxdrivers@attotech.com)mpt3sas/mpt3sas_trigger_diag.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * 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.
 *
 * NO WARRANTY
 * THE PROGRAM IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR
 * CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT
 * LIMITATION, ANY WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT,
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Each Recipient is
 * solely responsible for determining the appropriateness of using and
 * distributing the Program and assumes all risks associated with its
 * exercise of rights under this Agreement, including but not limited to
 * the risks and costs of program errors, damage to or loss of data,
 * programs or equipment, and unavailability or interruption of operations.
 *
 * DISCLAIMER OF LIABILITY
 * NEITHER RECIPIENT NOR ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 * USE OR DISTRIBUTION OF THE PROGRAM OR THE EXERCISE OF ANY RIGHTS GRANTED
 * HEREUNDER, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES
 *
 * 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 Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 */

#include "esas2r.h"

static bool esas2r_initmem_alloc(struct esas2r_adapter *a,
                                 struct esas2r_mem_desc *mem_desc,
                                 u32 align)
{
        mem_desc->esas2r_param = mem_desc->size + align;
        mem_desc->virt_addr = NULL;
        mem_desc->phys_addr = 0;
        mem_desc->esas2r_data = dma_alloc_coherent(&a->pcid->dev,
                                                   (size_t)mem_desc->
                                                   esas2r_param,
                                                   (dma_addr_t *)&mem_desc->
                                                   phys_addr,
                                                   GFP_KERNEL);

        if (mem_desc->esas2r_data == NULL) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "failed to allocate %lu bytes of consistent memory!",
                           (long
                            unsigned
                            int)mem_desc->esas2r_param);
                return false;
        }

        mem_desc->virt_addr = PTR_ALIGN(mem_desc->esas2r_data, align);
        mem_desc->phys_addr = ALIGN(mem_desc->phys_addr, align);
        memset(mem_desc->virt_addr, 0, mem_desc->size);
        return true;
}

static void esas2r_initmem_free(struct esas2r_adapter *a,
                                struct esas2r_mem_desc *mem_desc)
{
        if (mem_desc->virt_addr == NULL)
                return;

        /*
         * Careful!  phys_addr and virt_addr may have been adjusted from the
         * original allocation in order to return the desired alignment.  That
         * means we have to use the original address (in esas2r_data) and size
         * (esas2r_param) and calculate the original physical address based on
         * the difference between the requested and actual allocation size.
         */
        if (mem_desc->phys_addr) {
                int unalign = ((u8 *)mem_desc->virt_addr) -
                              ((u8 *)mem_desc->esas2r_data);

                dma_free_coherent(&a->pcid->dev,
                                  (size_t)mem_desc->esas2r_param,
                                  mem_desc->esas2r_data,
                                  (dma_addr_t)(mem_desc->phys_addr - unalign));
        } else {
                kfree(mem_desc->esas2r_data);
        }

        mem_desc->virt_addr = NULL;
}

static bool alloc_vda_req(struct esas2r_adapter *a,
                          struct esas2r_request *rq)
{
        struct esas2r_mem_desc *memdesc = kzalloc(
                sizeof(struct esas2r_mem_desc), GFP_KERNEL);

        if (memdesc == NULL) {
                esas2r_hdebug("could not alloc mem for vda request memdesc\n");
                return false;
        }

        memdesc->size = sizeof(union atto_vda_req) +
                        ESAS2R_DATA_BUF_LEN;

        if (!esas2r_initmem_alloc(a, memdesc, 256)) {
                esas2r_hdebug("could not alloc mem for vda request\n");
                kfree(memdesc);
                return false;
        }

        a->num_vrqs++;
        list_add(&memdesc->next_desc, &a->vrq_mds_head);

        rq->vrq_md = memdesc;
        rq->vrq = (union atto_vda_req *)memdesc->virt_addr;
        rq->vrq->scsi.handle = a->num_vrqs;

        return true;
}

static void esas2r_unmap_regions(struct esas2r_adapter *a)
{
        if (a->regs)
                iounmap((void __iomem *)a->regs);

        a->regs = NULL;

        pci_release_region(a->pcid, 2);

        if (a->data_window)
                iounmap((void __iomem *)a->data_window);

        a->data_window = NULL;

        pci_release_region(a->pcid, 0);
}

static int esas2r_map_regions(struct esas2r_adapter *a)
{
        int error;

        a->regs = NULL;
        a->data_window = NULL;

        error = pci_request_region(a->pcid, 2, a->name);
        if (error != 0) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "pci_request_region(2) failed, error %d",
                           error);

                return error;
        }

        a->regs = (void __force *)ioremap(pci_resource_start(a->pcid, 2),
                                          pci_resource_len(a->pcid, 2));
        if (a->regs == NULL) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "ioremap failed for regs mem region\n");
                pci_release_region(a->pcid, 2);
                return -EFAULT;
        }

        error = pci_request_region(a->pcid, 0, a->name);
        if (error != 0) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "pci_request_region(2) failed, error %d",
                           error);
                esas2r_unmap_regions(a);
                return error;
        }

        a->data_window = (void __force *)ioremap(pci_resource_start(a->pcid,
                                                                    0),
                                                 pci_resource_len(a->pcid, 0));
        if (a->data_window == NULL) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "ioremap failed for data_window mem region\n");
                esas2r_unmap_regions(a);
                return -EFAULT;
        }

        return 0;
}

static void esas2r_setup_interrupts(struct esas2r_adapter *a, int intr_mode)
{
        int i;

        /* Set up interrupt mode based on the requested value */
        switch (intr_mode) {
        case INTR_MODE_LEGACY:
use_legacy_interrupts:
                a->intr_mode = INTR_MODE_LEGACY;
                break;

        case INTR_MODE_MSI:
                i = pci_enable_msi(a->pcid);
                if (i != 0) {
                        esas2r_log(ESAS2R_LOG_WARN,
                                   "failed to enable MSI for adapter %d, "
                                   "falling back to legacy interrupts "
                                   "(err=%d)", a->index,
                                   i);
                        goto use_legacy_interrupts;
                }
                a->intr_mode = INTR_MODE_MSI;
                set_bit(AF2_MSI_ENABLED, &a->flags2);
                break;


        default:
                esas2r_log(ESAS2R_LOG_WARN,
                           "unknown interrupt_mode %d requested, "
                           "falling back to legacy interrupt",
                           interrupt_mode);
                goto use_legacy_interrupts;
        }
}

static void esas2r_claim_interrupts(struct esas2r_adapter *a)
{
        unsigned long flags = 0;

        if (a->intr_mode == INTR_MODE_LEGACY)
                flags |= IRQF_SHARED;

        esas2r_log(ESAS2R_LOG_INFO,
                   "esas2r_claim_interrupts irq=%d (%p, %s, %lx)",
                   a->pcid->irq, a, a->name, flags);

        if (request_irq(a->pcid->irq,
                        (a->intr_mode ==
                         INTR_MODE_LEGACY) ? esas2r_interrupt :
                        esas2r_msi_interrupt,
                        flags,
                        a->name,
                        a)) {
                esas2r_log(ESAS2R_LOG_CRIT, "unable to request IRQ %02X",
                           a->pcid->irq);
                return;
        }

        set_bit(AF2_IRQ_CLAIMED, &a->flags2);
        esas2r_log(ESAS2R_LOG_INFO,
                   "claimed IRQ %d flags: 0x%lx",
                   a->pcid->irq, flags);
}

int esas2r_init_adapter(struct Scsi_Host *host, struct pci_dev *pcid,
                        int index)
{
        struct esas2r_adapter *a;
        u64 bus_addr = 0;
        int i;
        void *next_uncached;
        struct esas2r_request *first_request, *last_request;
        bool dma64 = false;

        if (index >= MAX_ADAPTERS) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "tried to init invalid adapter index %u!",
                           index);
                return 0;
        }

        if (esas2r_adapters[index]) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "tried to init existing adapter index %u!",
                           index);
                return 0;
        }

        a = (struct esas2r_adapter *)host->hostdata;
        memset(a, 0, sizeof(struct esas2r_adapter));
        a->pcid = pcid;
        a->host = host;

        if (sizeof(dma_addr_t) > 4 &&
            dma_get_required_mask(&pcid->dev) > DMA_BIT_MASK(32) &&
            !dma_set_mask_and_coherent(&pcid->dev, DMA_BIT_MASK(64)))
                dma64 = true;

        if (!dma64 && dma_set_mask_and_coherent(&pcid->dev, DMA_BIT_MASK(32))) {
                esas2r_log(ESAS2R_LOG_CRIT, "failed to set DMA mask");
                esas2r_kill_adapter(index);
                return 0;
        }

        esas2r_log_dev(ESAS2R_LOG_INFO, &pcid->dev,
                       "%s-bit PCI addressing enabled\n", dma64 ? "64" : "32");

        esas2r_adapters[index] = a;
        sprintf(a->name, ESAS2R_DRVR_NAME "_%02d", index);
        esas2r_debug("new adapter %p, name %s", a, a->name);
        spin_lock_init(&a->request_lock);
        spin_lock_init(&a->fw_event_lock);
        mutex_init(&a->fm_api_mutex);
        mutex_init(&a->fs_api_mutex);
        sema_init(&a->nvram_semaphore, 1);

        esas2r_fw_event_off(a);
        snprintf(a->fw_event_q_name, ESAS2R_KOBJ_NAME_LEN, "esas2r/%d",
                 a->index);
        a->fw_event_q = create_singlethread_workqueue(a->fw_event_q_name);

        init_waitqueue_head(&a->buffered_ioctl_waiter);
        init_waitqueue_head(&a->nvram_waiter);
        init_waitqueue_head(&a->fm_api_waiter);
        init_waitqueue_head(&a->fs_api_waiter);
        init_waitqueue_head(&a->vda_waiter);

        INIT_LIST_HEAD(&a->general_req.req_list);
        INIT_LIST_HEAD(&a->active_list);
        INIT_LIST_HEAD(&a->defer_list);
        INIT_LIST_HEAD(&a->free_sg_list_head);
        INIT_LIST_HEAD(&a->avail_request);
        INIT_LIST_HEAD(&a->vrq_mds_head);
        INIT_LIST_HEAD(&a->fw_event_list);

        first_request = (struct esas2r_request *)((u8 *)(a + 1));

        for (last_request = first_request, i = 1; i < num_requests;
             last_request++, i++) {
                INIT_LIST_HEAD(&last_request->req_list);
                list_add_tail(&last_request->comp_list, &a->avail_request);
                if (!alloc_vda_req(a, last_request)) {
                        esas2r_log(ESAS2R_LOG_CRIT,
                                   "failed to allocate a VDA request!");
                        esas2r_kill_adapter(index);
                        return 0;
                }
        }

        esas2r_debug("requests: %p to %p (%d, %d)", first_request,
                     last_request,
                     sizeof(*first_request),
                     num_requests);

        if (esas2r_map_regions(a) != 0) {
                esas2r_log(ESAS2R_LOG_CRIT, "could not map PCI regions!");
                esas2r_kill_adapter(index);
                return 0;
        }

        a->index = index;

        /* interrupts will be disabled until we are done with init */
        atomic_inc(&a->dis_ints_cnt);
        atomic_inc(&a->disable_cnt);
        set_bit(AF_CHPRST_PENDING, &a->flags);
        set_bit(AF_DISC_PENDING, &a->flags);
        set_bit(AF_FIRST_INIT, &a->flags);
        set_bit(AF_LEGACY_SGE_MODE, &a->flags);

        a->init_msg = ESAS2R_INIT_MSG_START;
        a->max_vdareq_size = 128;
        a->build_sgl = esas2r_build_sg_list_sge;

        esas2r_setup_interrupts(a, interrupt_mode);

        a->uncached_size = esas2r_get_uncached_size(a);
        a->uncached = dma_alloc_coherent(&pcid->dev,
                                         (size_t)a->uncached_size,
                                         (dma_addr_t *)&bus_addr,
                                         GFP_KERNEL);
        if (a->uncached == NULL) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "failed to allocate %d bytes of consistent memory!",
                           a->uncached_size);
                esas2r_kill_adapter(index);
                return 0;
        }

        a->uncached_phys = bus_addr;

        esas2r_debug("%d bytes uncached memory allocated @ %p (%x:%x)",
                     a->uncached_size,
                     a->uncached,
                     upper_32_bits(bus_addr),
                     lower_32_bits(bus_addr));
        memset(a->uncached, 0, a->uncached_size);
        next_uncached = a->uncached;

        if (!esas2r_init_adapter_struct(a,
                                        &next_uncached)) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "failed to initialize adapter structure (2)!");
                esas2r_kill_adapter(index);
                return 0;
        }

        tasklet_init(&a->tasklet,
                     esas2r_adapter_tasklet,
                     (unsigned long)a);

        /*
         * Disable chip interrupts to prevent spurious interrupts
         * until we claim the IRQ.
         */
        esas2r_disable_chip_interrupts(a);
        esas2r_check_adapter(a);

        if (!esas2r_init_adapter_hw(a, true)) {
                esas2r_log(ESAS2R_LOG_CRIT, "failed to initialize hardware!");
        } else {
                esas2r_debug("esas2r_init_adapter ok");
        }

        esas2r_claim_interrupts(a);

        if (test_bit(AF2_IRQ_CLAIMED, &a->flags2))
                esas2r_enable_chip_interrupts(a);

        set_bit(AF2_INIT_DONE, &a->flags2);
        if (!test_bit(AF_DEGRADED_MODE, &a->flags))
                esas2r_kickoff_timer(a);
        esas2r_debug("esas2r_init_adapter done for %p (%d)",
                     a, a->disable_cnt);

        return 1;
}

static void esas2r_adapter_power_down(struct esas2r_adapter *a,
                                      int power_management)
{
        struct esas2r_mem_desc *memdesc, *next;

        if ((test_bit(AF2_INIT_DONE, &a->flags2))
            &&  (!test_bit(AF_DEGRADED_MODE, &a->flags))) {
                if (!power_management) {
                        del_timer_sync(&a->timer);
                        tasklet_kill(&a->tasklet);
                }
                esas2r_power_down(a);

                /*
                 * There are versions of firmware that do not handle the sync
                 * cache command correctly.  Stall here to ensure that the
                 * cache is lazily flushed.
                 */
                mdelay(500);
                esas2r_debug("chip halted");
        }

        /* Remove sysfs binary files */
        if (a->sysfs_fw_created) {
                sysfs_remove_bin_file(&a->host->shost_dev.kobj, &bin_attr_fw);
                a->sysfs_fw_created = 0;
        }

        if (a->sysfs_fs_created) {
                sysfs_remove_bin_file(&a->host->shost_dev.kobj, &bin_attr_fs);
                a->sysfs_fs_created = 0;
        }

        if (a->sysfs_vda_created) {
                sysfs_remove_bin_file(&a->host->shost_dev.kobj, &bin_attr_vda);
                a->sysfs_vda_created = 0;
        }

        if (a->sysfs_hw_created) {
                sysfs_remove_bin_file(&a->host->shost_dev.kobj, &bin_attr_hw);
                a->sysfs_hw_created = 0;
        }

        if (a->sysfs_live_nvram_created) {
                sysfs_remove_bin_file(&a->host->shost_dev.kobj,
                                      &bin_attr_live_nvram);
                a->sysfs_live_nvram_created = 0;
        }

        if (a->sysfs_default_nvram_created) {
                sysfs_remove_bin_file(&a->host->shost_dev.kobj,
                                      &bin_attr_default_nvram);
                a->sysfs_default_nvram_created = 0;
        }

        /* Clean up interrupts */
        if (test_bit(AF2_IRQ_CLAIMED, &a->flags2)) {
                esas2r_log_dev(ESAS2R_LOG_INFO,
                               &(a->pcid->dev),
                               "free_irq(%d) called", a->pcid->irq);

                free_irq(a->pcid->irq, a);
                esas2r_debug("IRQ released");
                clear_bit(AF2_IRQ_CLAIMED, &a->flags2);
        }

        if (test_bit(AF2_MSI_ENABLED, &a->flags2)) {
                pci_disable_msi(a->pcid);
                clear_bit(AF2_MSI_ENABLED, &a->flags2);
                esas2r_debug("MSI disabled");
        }

        if (a->inbound_list_md.virt_addr)
                esas2r_initmem_free(a, &a->inbound_list_md);

        if (a->outbound_list_md.virt_addr)
                esas2r_initmem_free(a, &a->outbound_list_md);

        list_for_each_entry_safe(memdesc, next, &a->free_sg_list_head,
                                 next_desc) {
                esas2r_initmem_free(a, memdesc);
        }

        /* Following frees everything allocated via alloc_vda_req */
        list_for_each_entry_safe(memdesc, next, &a->vrq_mds_head, next_desc) {
                esas2r_initmem_free(a, memdesc);
                list_del(&memdesc->next_desc);
                kfree(memdesc);
        }

        kfree(a->first_ae_req);
        a->first_ae_req = NULL;

        kfree(a->sg_list_mds);
        a->sg_list_mds = NULL;

        kfree(a->req_table);
        a->req_table = NULL;

        if (a->regs) {
                esas2r_unmap_regions(a);
                a->regs = NULL;
                a->data_window = NULL;
                esas2r_debug("regions unmapped");
        }
}

/* Release/free allocated resources for specified adapters. */
void esas2r_kill_adapter(int i)
{
        struct esas2r_adapter *a = esas2r_adapters[i];

        if (a) {
                unsigned long flags;
                struct workqueue_struct *wq;
                esas2r_debug("killing adapter %p [%d] ", a, i);
                esas2r_fw_event_off(a);
                esas2r_adapter_power_down(a, 0);
                if (esas2r_buffered_ioctl &&
                    (a->pcid == esas2r_buffered_ioctl_pcid)) {
                        dma_free_coherent(&a->pcid->dev,
                                          (size_t)esas2r_buffered_ioctl_size,
                                          esas2r_buffered_ioctl,
                                          esas2r_buffered_ioctl_addr);
                        esas2r_buffered_ioctl = NULL;
                }

                if (a->vda_buffer) {
                        dma_free_coherent(&a->pcid->dev,
                                          (size_t)VDA_MAX_BUFFER_SIZE,
                                          a->vda_buffer,
                                          (dma_addr_t)a->ppvda_buffer);
                        a->vda_buffer = NULL;
                }
                if (a->fs_api_buffer) {
                        dma_free_coherent(&a->pcid->dev,
                                          (size_t)a->fs_api_buffer_size,
                                          a->fs_api_buffer,
                                          (dma_addr_t)a->ppfs_api_buffer);
                        a->fs_api_buffer = NULL;
                }

                kfree(a->local_atto_ioctl);
                a->local_atto_ioctl = NULL;

                spin_lock_irqsave(&a->fw_event_lock, flags);
                wq = a->fw_event_q;
                a->fw_event_q = NULL;
                spin_unlock_irqrestore(&a->fw_event_lock, flags);
                if (wq)
                        destroy_workqueue(wq);

                if (a->uncached) {
                        dma_free_coherent(&a->pcid->dev,
                                          (size_t)a->uncached_size,
                                          a->uncached,
                                          (dma_addr_t)a->uncached_phys);
                        a->uncached = NULL;
                        esas2r_debug("uncached area freed");
                }

                esas2r_log_dev(ESAS2R_LOG_INFO,
                               &(a->pcid->dev),
                               "pci_disable_device() called.  msix_enabled: %d "
                               "msi_enabled: %d irq: %d pin: %d",
                               a->pcid->msix_enabled,
                               a->pcid->msi_enabled,
                               a->pcid->irq,
                               a->pcid->pin);

                esas2r_log_dev(ESAS2R_LOG_INFO,
                               &(a->pcid->dev),
                               "before pci_disable_device() enable_cnt: %d",
                               a->pcid->enable_cnt.counter);

                pci_disable_device(a->pcid);
                esas2r_log_dev(ESAS2R_LOG_INFO,
                               &(a->pcid->dev),
                               "after pci_disable_device() enable_cnt: %d",
                               a->pcid->enable_cnt.counter);

                esas2r_log_dev(ESAS2R_LOG_INFO,
                               &(a->pcid->dev),
                               "pci_set_drv_data(%p, NULL) called",
                               a->pcid);

                pci_set_drvdata(a->pcid, NULL);
                esas2r_adapters[i] = NULL;

                if (test_bit(AF2_INIT_DONE, &a->flags2)) {
                        clear_bit(AF2_INIT_DONE, &a->flags2);

                        set_bit(AF_DEGRADED_MODE, &a->flags);

                        esas2r_log_dev(ESAS2R_LOG_INFO,
                                       &(a->host->shost_gendev),
                                       "scsi_remove_host() called");

                        scsi_remove_host(a->host);

                        esas2r_log_dev(ESAS2R_LOG_INFO,
                                       &(a->host->shost_gendev),
                                       "scsi_host_put() called");

                        scsi_host_put(a->host);
                }
        }
}

static int __maybe_unused esas2r_suspend(struct device *dev)
{
        struct Scsi_Host *host = dev_get_drvdata(dev);
        struct esas2r_adapter *a = (struct esas2r_adapter *)host->hostdata;

        esas2r_log_dev(ESAS2R_LOG_INFO, dev, "suspending adapter()");
        if (!a)
                return -ENODEV;

        esas2r_adapter_power_down(a, 1);
        esas2r_log_dev(ESAS2R_LOG_INFO, dev, "esas2r_suspend(): 0");
        return 0;
}

static int __maybe_unused esas2r_resume(struct device *dev)
{
        struct Scsi_Host *host = dev_get_drvdata(dev);
        struct esas2r_adapter *a = (struct esas2r_adapter *)host->hostdata;
        int rez = 0;

        esas2r_log_dev(ESAS2R_LOG_INFO, dev, "resuming adapter()");

        if (!a) {
                rez = -ENODEV;
                goto error_exit;
        }

        if (esas2r_map_regions(a) != 0) {
                esas2r_log(ESAS2R_LOG_CRIT, "could not re-map PCI regions!");
                rez = -ENOMEM;
                goto error_exit;
        }

        /* Set up interupt mode */
        esas2r_setup_interrupts(a, a->intr_mode);

        /*
         * Disable chip interrupts to prevent spurious interrupts until we
         * claim the IRQ.
         */
        esas2r_disable_chip_interrupts(a);
        if (!esas2r_power_up(a, true)) {
                esas2r_debug("yikes, esas2r_power_up failed");
                rez = -ENOMEM;
                goto error_exit;
        }

        esas2r_claim_interrupts(a);

        if (test_bit(AF2_IRQ_CLAIMED, &a->flags2)) {
                /*
                 * Now that system interrupt(s) are claimed, we can enable
                 * chip interrupts.
                 */
                esas2r_enable_chip_interrupts(a);
                esas2r_kickoff_timer(a);
        } else {
                esas2r_debug("yikes, unable to claim IRQ");
                esas2r_log(ESAS2R_LOG_CRIT, "could not re-claim IRQ!");
                rez = -ENOMEM;
                goto error_exit;
        }

error_exit:
        esas2r_log_dev(ESAS2R_LOG_CRIT, dev, "esas2r_resume(): %d",
                       rez);
        return rez;
}

SIMPLE_DEV_PM_OPS(esas2r_pm_ops, esas2r_suspend, esas2r_resume);

bool esas2r_set_degraded_mode(struct esas2r_adapter *a, char *error_str)
{
        set_bit(AF_DEGRADED_MODE, &a->flags);
        esas2r_log(ESAS2R_LOG_CRIT,
                   "setting adapter to degraded mode: %s\n", error_str);
        return false;
}

u32 esas2r_get_uncached_size(struct esas2r_adapter *a)
{
        return sizeof(struct esas2r_sas_nvram)
               + ALIGN(ESAS2R_DISC_BUF_LEN, 8)
               + ALIGN(sizeof(u32), 8) /* outbound list copy pointer */
               + 8
               + (num_sg_lists * (u16)sgl_page_size)
               + ALIGN((num_requests + num_ae_requests + 1 +
                        ESAS2R_LIST_EXTRA) *
                       sizeof(struct esas2r_inbound_list_source_entry),
                       8)
               + ALIGN((num_requests + num_ae_requests + 1 +
                        ESAS2R_LIST_EXTRA) *
                       sizeof(struct atto_vda_ob_rsp), 8)
               + 256; /* VDA request and buffer align */
}

static void esas2r_init_pci_cfg_space(struct esas2r_adapter *a)
{
        if (pci_is_pcie(a->pcid)) {
                u16 devcontrol;

                pcie_capability_read_word(a->pcid, PCI_EXP_DEVCTL, &devcontrol);

                if ((devcontrol & PCI_EXP_DEVCTL_READRQ) >
                     PCI_EXP_DEVCTL_READRQ_512B) {
                        esas2r_log(ESAS2R_LOG_INFO,
                                   "max read request size > 512B");

                        devcontrol &= ~PCI_EXP_DEVCTL_READRQ;
                        devcontrol |= PCI_EXP_DEVCTL_READRQ_512B;
                        pcie_capability_write_word(a->pcid, PCI_EXP_DEVCTL,
                                                   devcontrol);
                }
        }
}

/*
 * Determine the organization of the uncached data area and
 * finish initializing the adapter structure
 */
bool esas2r_init_adapter_struct(struct esas2r_adapter *a,
                                void **uncached_area)
{
        u32 i;
        u8 *high;
        struct esas2r_inbound_list_source_entry *element;
        struct esas2r_request *rq;
        struct esas2r_mem_desc *sgl;

        spin_lock_init(&a->sg_list_lock);
        spin_lock_init(&a->mem_lock);
        spin_lock_init(&a->queue_lock);

        a->targetdb_end = &a->targetdb[ESAS2R_MAX_TARGETS];

        if (!alloc_vda_req(a, &a->general_req)) {
                esas2r_hdebug(
                        "failed to allocate a VDA request for the general req!");
                return false;
        }

        /* allocate requests for asynchronous events */
        a->first_ae_req =
                kcalloc(num_ae_requests, sizeof(struct esas2r_request),
                        GFP_KERNEL);

        if (a->first_ae_req == NULL) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "failed to allocate memory for asynchronous events");
                return false;
        }

        /* allocate the S/G list memory descriptors */
        a->sg_list_mds = kcalloc(num_sg_lists, sizeof(struct esas2r_mem_desc),
                                 GFP_KERNEL);

        if (a->sg_list_mds == NULL) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "failed to allocate memory for s/g list descriptors");
                return false;
        }

        /* allocate the request table */
        a->req_table =
                kcalloc(num_requests + num_ae_requests + 1,
                        sizeof(struct esas2r_request *),
                        GFP_KERNEL);

        if (a->req_table == NULL) {
                esas2r_log(ESAS2R_LOG_CRIT,
                           "failed to allocate memory for the request table");
                return false;
        }

        /* initialize PCI configuration space */
        esas2r_init_pci_cfg_space(a);

        /*
         * the thunder_stream boards all have a serial flash part that has a
         * different base address on the AHB bus.
         */
        if ((a->pcid->subsystem_vendor == ATTO_VENDOR_ID)
            && (a->pcid->subsystem_device & ATTO_SSDID_TBT))
                a->flags2 |= AF2_THUNDERBOLT;

        if (test_bit(AF2_THUNDERBOLT, &a->flags2))
                a->flags2 |= AF2_SERIAL_FLASH;

        if (a->pcid->subsystem_device == ATTO_TLSH_1068)
                a->flags2 |= AF2_THUNDERLINK;

        /* Uncached Area */
        high = (u8 *)*uncached_area;

        /* initialize the scatter/gather table pages */

        for (i = 0, sgl = a->sg_list_mds; i < num_sg_lists; i++, sgl++) {
                sgl->size = sgl_page_size;

                list_add_tail(&sgl->next_desc, &a->free_sg_list_head);

                if (!esas2r_initmem_alloc(a, sgl, ESAS2R_SGL_ALIGN)) {
                        /* Allow the driver to load if the minimum count met. */
                        if (i < NUM_SGL_MIN)
                                return false;
                        break;
                }
        }

        /* compute the size of the lists */
        a->list_size = num_requests + ESAS2R_LIST_EXTRA;

        /* allocate the inbound list */
        a->inbound_list_md.size = a->list_size *
                                  sizeof(struct
                                         esas2r_inbound_list_source_entry);

        if (!esas2r_initmem_alloc(a, &a->inbound_list_md, ESAS2R_LIST_ALIGN)) {
                esas2r_hdebug("failed to allocate IB list");
                return false;
        }

        /* allocate the outbound list */
        a->outbound_list_md.size = a->list_size *
                                   sizeof(struct atto_vda_ob_rsp);

        if (!esas2r_initmem_alloc(a, &a->outbound_list_md,
                                  ESAS2R_LIST_ALIGN)) {
                esas2r_hdebug("failed to allocate IB list");
                return false;
        }

        /* allocate the NVRAM structure */
        a->nvram = (struct esas2r_sas_nvram *)high;
        high += sizeof(struct esas2r_sas_nvram);

        /* allocate the discovery buffer */
        a->disc_buffer = high;
        high += ESAS2R_DISC_BUF_LEN;
        high = PTR_ALIGN(high, 8);

        /* allocate the outbound list copy pointer */
        a->outbound_copy = (u32 volatile *)high;
        high += sizeof(u32);

        if (!test_bit(AF_NVR_VALID, &a->flags))
                esas2r_nvram_set_defaults(a);

        /* update the caller's uncached memory area pointer */
        *uncached_area = (void *)high;

        /* initialize the allocated memory */
        if (test_bit(AF_FIRST_INIT, &a->flags)) {
                esas2r_targ_db_initialize(a);

                /* prime parts of the inbound list */
                element =
                        (struct esas2r_inbound_list_source_entry *)a->
                        inbound_list_md.
                        virt_addr;

                for (i = 0; i < a->list_size; i++) {
                        element->address = 0;
                        element->reserved = 0;
                        element->length = cpu_to_le32(HWILSE_INTERFACE_F0
                                                      | (sizeof(union
                                                                atto_vda_req)
                                                         /
                                                         sizeof(u32)));
                        element++;
                }

                /* init the AE requests */
                for (rq = a->first_ae_req, i = 0; i < num_ae_requests; rq++,
                     i++) {
                        INIT_LIST_HEAD(&rq->req_list);
                        if (!alloc_vda_req(a, rq)) {
                                esas2r_hdebug(
                                        "failed to allocate a VDA request!");
                                return false;
                        }

                        esas2r_rq_init_request(rq, a);

                        /* override the completion function */
                        rq->comp_cb = esas2r_ae_complete;
                }
        }

        return true;
}

/* This code will verify that the chip is operational. */
bool esas2r_check_adapter(struct esas2r_adapter *a)
{
        u32 starttime;
        u32 doorbell;
        u64 ppaddr;
        u32 dw;

        /*
         * if the chip reset detected flag is set, we can bypass a bunch of
         * stuff.
         */
        if (test_bit(AF_CHPRST_DETECTED, &a->flags))
                goto skip_chip_reset;

        /*
         * BEFORE WE DO ANYTHING, disable the chip interrupts!  the boot driver
         * may have left them enabled or we may be recovering from a fault.
         */
        esas2r_write_register_dword(a, MU_INT_MASK_OUT, ESAS2R_INT_DIS_MASK);
        esas2r_flush_register_dword(a, MU_INT_MASK_OUT);

        /*
         * wait for the firmware to become ready by forcing an interrupt and
         * waiting for a response.
         */
        starttime = jiffies_to_msecs(jiffies);

        while (true) {
                esas2r_force_interrupt(a);
                doorbell = esas2r_read_register_dword(a, MU_DOORBELL_OUT);
                if (doorbell == 0xFFFFFFFF) {
                        /*
                         * Give the firmware up to two seconds to enable
                         * register access after a reset.
                         */
                        if ((jiffies_to_msecs(jiffies) - starttime) > 2000)
                                return esas2r_set_degraded_mode(a,
                                                                "unable to access registers");
                } else if (doorbell & DRBL_FORCE_INT) {
                        u32 ver = (doorbell & DRBL_FW_VER_MSK);

                        /*
                         * This driver supports version 0 and version 1 of
                         * the API
                         */
                        esas2r_write_register_dword(a, MU_DOORBELL_OUT,
                                                    doorbell);

                        if (ver == DRBL_FW_VER_0) {
                                set_bit(AF_LEGACY_SGE_MODE, &a->flags);

                                a->max_vdareq_size = 128;
                                a->build_sgl = esas2r_build_sg_list_sge;
                        } else if (ver == DRBL_FW_VER_1) {
                                clear_bit(AF_LEGACY_SGE_MODE, &a->flags);

                                a->max_vdareq_size = 1024;
                                a->build_sgl = esas2r_build_sg_list_prd;
                        } else {
                                return esas2r_set_degraded_mode(a,
                                                                "unknown firmware version");
                        }
                        break;
                }

                schedule_timeout_interruptible(msecs_to_jiffies(100));

                if ((jiffies_to_msecs(jiffies) - starttime) > 180000) {
                        esas2r_hdebug("FW ready TMO");
                        esas2r_bugon();

                        return esas2r_set_degraded_mode(a,
                                                        "firmware start has timed out");
                }
        }

        /* purge any asynchronous events since we will repost them later */
        esas2r_write_register_dword(a, MU_DOORBELL_IN, DRBL_MSG_IFC_DOWN);
        starttime = jiffies_to_msecs(jiffies);

        while (true) {
                doorbell = esas2r_read_register_dword(a, MU_DOORBELL_OUT);
                if (doorbell & DRBL_MSG_IFC_DOWN) {
                        esas2r_write_register_dword(a, MU_DOORBELL_OUT,
                                                    doorbell);
                        break;
                }

                schedule_timeout_interruptible(msecs_to_jiffies(50));

                if ((jiffies_to_msecs(jiffies) - starttime) > 3000) {
                        esas2r_hdebug("timeout waiting for interface down");
                        break;
                }
        }
skip_chip_reset:
        /*
         * first things first, before we go changing any of these registers
         * disable the communication lists.
         */
        dw = esas2r_read_register_dword(a, MU_IN_LIST_CONFIG);
        dw &= ~MU_ILC_ENABLE;
        esas2r_write_register_dword(a, MU_IN_LIST_CONFIG, dw);
        dw = esas2r_read_register_dword(a, MU_OUT_LIST_CONFIG);
        dw &= ~MU_OLC_ENABLE;
        esas2r_write_register_dword(a, MU_OUT_LIST_CONFIG, dw);

        /* configure the communication list addresses */
        ppaddr = a->inbound_list_md.phys_addr;
        esas2r_write_register_dword(a, MU_IN_LIST_ADDR_LO,
                                    lower_32_bits(ppaddr));
        esas2r_write_register_dword(a, MU_IN_LIST_ADDR_HI,
                                    upper_32_bits(ppaddr));
        ppaddr = a->outbound_list_md.phys_addr;
        esas2r_write_register_dword(a, MU_OUT_LIST_ADDR_LO,
                                    lower_32_bits(ppaddr));
        esas2r_write_register_dword(a, MU_OUT_LIST_ADDR_HI,
                                    upper_32_bits(ppaddr));
        ppaddr = a->uncached_phys +
                 ((u8 *)a->outbound_copy - a->uncached);
        esas2r_write_register_dword(a, MU_OUT_LIST_COPY_PTR_LO,
                                    lower_32_bits(ppaddr));
        esas2r_write_register_dword(a, MU_OUT_LIST_COPY_PTR_HI,
                                    upper_32_bits(ppaddr));

        /* reset the read and write pointers */
        *a->outbound_copy =
                a->last_write =
                        a->last_read = a->list_size - 1;
        set_bit(AF_COMM_LIST_TOGGLE, &a->flags);
        esas2r_write_register_dword(a, MU_IN_LIST_WRITE, MU_ILW_TOGGLE |
                                    a->last_write);
        esas2r_write_register_dword(a, MU_OUT_LIST_COPY, MU_OLC_TOGGLE |
                                    a->last_write);
        esas2r_write_register_dword(a, MU_IN_LIST_READ, MU_ILR_TOGGLE |
                                    a->last_write);
        esas2r_write_register_dword(a, MU_OUT_LIST_WRITE,
                                    MU_OLW_TOGGLE | a->last_write);

        /* configure the interface select fields */
        dw = esas2r_read_register_dword(a, MU_IN_LIST_IFC_CONFIG);
        dw &= ~(MU_ILIC_LIST | MU_ILIC_DEST);
        esas2r_write_register_dword(a, MU_IN_LIST_IFC_CONFIG,
                                    (dw | MU_ILIC_LIST_F0 | MU_ILIC_DEST_DDR));
        dw = esas2r_read_register_dword(a, MU_OUT_LIST_IFC_CONFIG);
        dw &= ~(MU_OLIC_LIST | MU_OLIC_SOURCE);
        esas2r_write_register_dword(a, MU_OUT_LIST_IFC_CONFIG,
                                    (dw | MU_OLIC_LIST_F0 |
                                     MU_OLIC_SOURCE_DDR));

        /* finish configuring the communication lists */
        dw = esas2r_read_register_dword(a, MU_IN_LIST_CONFIG);
        dw &= ~(MU_ILC_ENTRY_MASK | MU_ILC_NUMBER_MASK);
        dw |= MU_ILC_ENTRY_4_DW | MU_ILC_DYNAMIC_SRC
              | (a->list_size << MU_ILC_NUMBER_SHIFT);
        esas2r_write_register_dword(a, MU_IN_LIST_CONFIG, dw);
        dw = esas2r_read_register_dword(a, MU_OUT_LIST_CONFIG);
        dw &= ~(MU_OLC_ENTRY_MASK | MU_OLC_NUMBER_MASK);
        dw |= MU_OLC_ENTRY_4_DW | (a->list_size << MU_OLC_NUMBER_SHIFT);
        esas2r_write_register_dword(a, MU_OUT_LIST_CONFIG, dw);

        /*
         * notify the firmware that we're done setting up the communication
         * list registers.  wait here until the firmware is done configuring
         * its lists.  it will signal that it is done by enabling the lists.
         */
        esas2r_write_register_dword(a, MU_DOORBELL_IN, DRBL_MSG_IFC_INIT);
        starttime = jiffies_to_msecs(jiffies);

        while (true) {
                doorbell = esas2r_read_register_dword(a, MU_DOORBELL_OUT);
                if (doorbell & DRBL_MSG_IFC_INIT) {
                        esas2r_write_register_dword(a, MU_DOORBELL_OUT,
                                                    doorbell);
                        break;
                }

                schedule_timeout_interruptible(msecs_to_jiffies(100));

                if ((jiffies_to_msecs(jiffies) - starttime) > 3000) {
                        esas2r_hdebug(
                                "timeout waiting for communication list init");
                        esas2r_bugon();
                        return esas2r_set_degraded_mode(a,
                                                        "timeout waiting for communication list init");
                }
        }

        /*
         * flag whether the firmware supports the power down doorbell.  we
         * determine this by reading the inbound doorbell enable mask.
         */
        doorbell = esas2r_read_register_dword(a, MU_DOORBELL_IN_ENB);
        if (doorbell & DRBL_POWER_DOWN)
                set_bit(AF2_VDA_POWER_DOWN, &a->flags2);
        else
                clear_bit(AF2_VDA_POWER_DOWN, &a->flags2);

        /*
         * enable assertion of outbound queue and doorbell interrupts in the
         * main interrupt cause register.
         */
        esas2r_write_register_dword(a, MU_OUT_LIST_INT_MASK, MU_OLIS_MASK);
        esas2r_write_register_dword(a, MU_DOORBELL_OUT_ENB, DRBL_ENB_MASK);
        return true;
}

/* Process the initialization message just completed and format the next one. */
static bool esas2r_format_init_msg(struct esas2r_adapter *a,
                                   struct esas2r_request *rq)
{
        u32 msg = a->init_msg;
        struct atto_vda_cfg_init *ci;

        a->init_msg = 0;

        switch (msg) {
        case ESAS2R_INIT_MSG_START:
        case ESAS2R_INIT_MSG_REINIT:
        {
                esas2r_hdebug("CFG init");
                esas2r_build_cfg_req(a,
                                     rq,
                                     VDA_CFG_INIT,
                                     0,
                                     NULL);
                ci = (struct atto_vda_cfg_init *)&rq->vrq->cfg.data.init;
                ci->sgl_page_size = cpu_to_le32(sgl_page_size);
                /* firmware interface overflows in y2106 */
                ci->epoch_time = cpu_to_le32(ktime_get_real_seconds());
                rq->flags |= RF_FAILURE_OK;
                a->init_msg = ESAS2R_INIT_MSG_INIT;
                break;
        }

        case ESAS2R_INIT_MSG_INIT:
                if (rq->req_stat == RS_SUCCESS) {
                        u32 major;
                        u32 minor;
                        u16 fw_release;

                        a->fw_version = le16_to_cpu(
                                rq->func_rsp.cfg_rsp.vda_version);
                        a->fw_build = rq->func_rsp.cfg_rsp.fw_build;
                        fw_release = le16_to_cpu(
                                rq->func_rsp.cfg_rsp.fw_release);
                        major = LOBYTE(fw_release);
                        minor = HIBYTE(fw_release);
                        a->fw_version += (major << 16) + (minor << 24);
                } else {
                        esas2r_hdebug("FAILED");
                }

                /*
                 * the 2.71 and earlier releases of R6xx firmware did not error
                 * unsupported config requests correctly.
                 */

                if ((test_bit(AF2_THUNDERBOLT, &a->flags2))
                    || (be32_to_cpu(a->fw_version) > 0x00524702)) {
                        esas2r_hdebug("CFG get init");
                        esas2r_build_cfg_req(a,
                                             rq,
                                             VDA_CFG_GET_INIT2,
                                             sizeof(struct atto_vda_cfg_init),
                                             NULL);

                        rq->vrq->cfg.sg_list_offset = offsetof(
                                struct atto_vda_cfg_req,
                                data.sge);
                        rq->vrq->cfg.data.prde.ctl_len =
                                cpu_to_le32(sizeof(struct atto_vda_cfg_init));
                        rq->vrq->cfg.data.prde.address = cpu_to_le64(
                                rq->vrq_md->phys_addr +
                                sizeof(union atto_vda_req));
                        rq->flags |= RF_FAILURE_OK;
                        a->init_msg = ESAS2R_INIT_MSG_GET_INIT;
                        break;
                }
                fallthrough;

        case ESAS2R_INIT_MSG_GET_INIT:
                if (msg == ESAS2R_INIT_MSG_GET_INIT) {
                        ci = (struct atto_vda_cfg_init *)rq->data_buf;
                        if (rq->req_stat == RS_SUCCESS) {
                                a->num_targets_backend =
                                        le32_to_cpu(ci->num_targets_backend);
                                a->ioctl_tunnel =
                                        le32_to_cpu(ci->ioctl_tunnel);
                        } else {
                                esas2r_hdebug("FAILED");
                        }
                }
                fallthrough;

        default:
                rq->req_stat = RS_SUCCESS;
                return false;
        }
        return true;
}

/*
 * Perform initialization messages via the request queue.  Messages are
 * performed with interrupts disabled.
 */
bool esas2r_init_msgs(struct esas2r_adapter *a)
{
        bool success = true;
        struct esas2r_request *rq = &a->general_req;

        esas2r_rq_init_request(rq, a);
        rq->comp_cb = esas2r_dummy_complete;

        if (a->init_msg == 0)
                a->init_msg = ESAS2R_INIT_MSG_REINIT;

        while (a->init_msg) {
                if (esas2r_format_init_msg(a, rq)) {
                        unsigned long flags;
                        while (true) {
                                spin_lock_irqsave(&a->queue_lock, flags);
                                esas2r_start_vda_request(a, rq);
                                spin_unlock_irqrestore(&a->queue_lock, flags);
                                esas2r_wait_request(a, rq);
                                if (rq->req_stat != RS_PENDING)
                                        break;
                        }
                }

                if (rq->req_stat == RS_SUCCESS
                    || ((rq->flags & RF_FAILURE_OK)
                        && rq->req_stat != RS_TIMEOUT))
                        continue;

                esas2r_log(ESAS2R_LOG_CRIT, "init message %x failed (%x, %x)",
                           a->init_msg, rq->req_stat, rq->flags);
                a->init_msg = ESAS2R_INIT_MSG_START;
                success = false;
                break;
        }

        esas2r_rq_destroy_request(rq, a);
        return success;
}

/* Initialize the adapter chip */
bool esas2r_init_adapter_hw(struct esas2r_adapter *a, bool init_poll)
{
        bool rslt = false;
        struct esas2r_request *rq;
        u32 i;

        if (test_bit(AF_DEGRADED_MODE, &a->flags))
                goto exit;

        if (!test_bit(AF_NVR_VALID, &a->flags)) {
                if (!esas2r_nvram_read_direct(a))
                        esas2r_log(ESAS2R_LOG_WARN,
                                   "invalid/missing NVRAM parameters");
        }

        if (!esas2r_init_msgs(a)) {
                esas2r_set_degraded_mode(a, "init messages failed");
                goto exit;
        }

        /* The firmware is ready. */
        clear_bit(AF_DEGRADED_MODE, &a->flags);
        clear_bit(AF_CHPRST_PENDING, &a->flags);

        /* Post all the async event requests */
        for (i = 0, rq = a->first_ae_req; i < num_ae_requests; i++, rq++)
                esas2r_start_ae_request(a, rq);

        if (!a->flash_rev[0])
                esas2r_read_flash_rev(a);

        if (!a->image_type[0])
                esas2r_read_image_type(a);

        if (a->fw_version == 0)
                a->fw_rev[0] = 0;
        else
                sprintf(a->fw_rev, "%1d.%02d",
                        (int)LOBYTE(HIWORD(a->fw_version)),
                        (int)HIBYTE(HIWORD(a->fw_version)));

        esas2r_hdebug("firmware revision: %s", a->fw_rev);

        if (test_bit(AF_CHPRST_DETECTED, &a->flags)
            && (test_bit(AF_FIRST_INIT, &a->flags))) {
                esas2r_enable_chip_interrupts(a);
                return true;
        }

        /* initialize discovery */
        esas2r_disc_initialize(a);

        /*
         * wait for the device wait time to expire here if requested.  this is
         * usually requested during initial driver load and possibly when
         * resuming from a low power state.  deferred device waiting will use
         * interrupts.  chip reset recovery always defers device waiting to
         * avoid being in a TASKLET too long.
         */
        if (init_poll) {
                u32 currtime = a->disc_start_time;
                u32 nexttick = 100;
                u32 deltatime;

                /*
                 * Block Tasklets from getting scheduled and indicate this is
                 * polled discovery.
                 */
                set_bit(AF_TASKLET_SCHEDULED, &a->flags);
                set_bit(AF_DISC_POLLED, &a->flags);

                /*
                 * Temporarily bring the disable count to zero to enable
                 * deferred processing.  Note that the count is already zero
                 * after the first initialization.
                 */
                if (test_bit(AF_FIRST_INIT, &a->flags))
                        atomic_dec(&a->disable_cnt);

                while (test_bit(AF_DISC_PENDING, &a->flags)) {
                        schedule_timeout_interruptible(msecs_to_jiffies(100));

                        /*
                         * Determine the need for a timer tick based on the
                         * delta time between this and the last iteration of
                         * this loop.  We don't use the absolute time because
                         * then we would have to worry about when nexttick
                         * wraps and currtime hasn't yet.
                         */
                        deltatime = jiffies_to_msecs(jiffies) - currtime;
                        currtime += deltatime;

                        /*
                         * Process any waiting discovery as long as the chip is
                         * up.  If a chip reset happens during initial polling,
                         * we have to make sure the timer tick processes the
                         * doorbell indicating the firmware is ready.
                         */
                        if (!test_bit(AF_CHPRST_PENDING, &a->flags))
                                esas2r_disc_check_for_work(a);

                        /* Simulate a timer tick. */
                        if (nexttick <= deltatime) {

                                /* Time for a timer tick */
                                nexttick += 100;
                                esas2r_timer_tick(a);
                        }

                        if (nexttick > deltatime)
                                nexttick -= deltatime;

                        /* Do any deferred processing */
                        if (esas2r_is_tasklet_pending(a))
                                esas2r_do_tasklet_tasks(a);

                }

                if (test_bit(AF_FIRST_INIT, &a->flags))
                        atomic_inc(&a->disable_cnt);

                clear_bit(AF_DISC_POLLED, &a->flags);
                clear_bit(AF_TASKLET_SCHEDULED, &a->flags);
        }


        esas2r_targ_db_report_changes(a);

        /*
         * For cases where (a) the initialization messages processing may
         * handle an interrupt for a port event and a discovery is waiting, but
         * we are not waiting for devices, or (b) the device wait time has been
         * exhausted but there is still discovery pending, start any leftover
         * discovery in interrupt driven mode.
         */
        esas2r_disc_start_waiting(a);

        /* Enable chip interrupts */
        a->int_mask = ESAS2R_INT_STS_MASK;
        esas2r_enable_chip_interrupts(a);
        esas2r_enable_heartbeat(a);
        rslt = true;

exit:
        /*
         * Regardless of whether initialization was successful, certain things
         * need to get done before we exit.
         */

        if (test_bit(AF_CHPRST_DETECTED, &a->flags) &&
            test_bit(AF_FIRST_INIT, &a->flags)) {
                /*
                 * Reinitialization was performed during the first
                 * initialization.  Only clear the chip reset flag so the
                 * original device polling is not cancelled.
                 */
                if (!rslt)
                        clear_bit(AF_CHPRST_PENDING, &a->flags);
        } else {
                /* First initialization or a subsequent re-init is complete. */
                if (!rslt) {
                        clear_bit(AF_CHPRST_PENDING, &a->flags);
                        clear_bit(AF_DISC_PENDING, &a->flags);
                }


                /* Enable deferred processing after the first initialization. */
                if (test_bit(AF_FIRST_INIT, &a->flags)) {
                        clear_bit(AF_FIRST_INIT, &a->flags);

                        if (atomic_dec_return(&a->disable_cnt) == 0)
                                esas2r_do_deferred_processes(a);
                }
        }

        return rslt;
}

void esas2r_reset_adapter(struct esas2r_adapter *a)
{
        set_bit(AF_OS_RESET, &a->flags);
        esas2r_local_reset_adapter(a);
        esas2r_schedule_tasklet(a);
}

void esas2r_reset_chip(struct esas2r_adapter *a)
{
        if (!esas2r_is_adapter_present(a))
                return;

        /*
         * Before we reset the chip, save off the VDA core dump.  The VDA core
         * dump is located in the upper 512KB of the onchip SRAM.  Make sure
         * to not overwrite a previous crash that was saved.
         */
        if (test_bit(AF2_COREDUMP_AVAIL, &a->flags2) &&
            !test_bit(AF2_COREDUMP_SAVED, &a->flags2)) {
                esas2r_read_mem_block(a,
                                      a->fw_coredump_buff,
                                      MW_DATA_ADDR_SRAM + 0x80000,
                                      ESAS2R_FWCOREDUMP_SZ);

                set_bit(AF2_COREDUMP_SAVED, &a->flags2);
        }

        clear_bit(AF2_COREDUMP_AVAIL, &a->flags2);

        /* Reset the chip */
        if (a->pcid->revision == MVR_FREY_B2)
                esas2r_write_register_dword(a, MU_CTL_STATUS_IN_B2,
                                            MU_CTL_IN_FULL_RST2);
        else
                esas2r_write_register_dword(a, MU_CTL_STATUS_IN,
                                            MU_CTL_IN_FULL_RST);


        /* Stall a little while to let the reset condition clear */
        mdelay(10);
}

static void esas2r_power_down_notify_firmware(struct esas2r_adapter *a)
{
        u32 starttime;
        u32 doorbell;

        esas2r_write_register_dword(a, MU_DOORBELL_IN, DRBL_POWER_DOWN);
        starttime = jiffies_to_msecs(jiffies);

        while (true) {
                doorbell = esas2r_read_register_dword(a, MU_DOORBELL_OUT);
                if (doorbell & DRBL_POWER_DOWN) {
                        esas2r_write_register_dword(a, MU_DOORBELL_OUT,
                                                    doorbell);
                        break;
                }

                schedule_timeout_interruptible(msecs_to_jiffies(100));

                if ((jiffies_to_msecs(jiffies) - starttime) > 30000) {
                        esas2r_hdebug("Timeout waiting for power down");
                        break;
                }
        }
}

/*
 * Perform power management processing including managing device states, adapter
 * states, interrupts, and I/O.
 */
void esas2r_power_down(struct esas2r_adapter *a)
{
        set_bit(AF_POWER_MGT, &a->flags);
        set_bit(AF_POWER_DOWN, &a->flags);

        if (!test_bit(AF_DEGRADED_MODE, &a->flags)) {
                u32 starttime;
                u32 doorbell;

                /*
                 * We are currently running OK and will be reinitializing later.
                 * increment the disable count to coordinate with
                 * esas2r_init_adapter.  We don't have to do this in degraded
                 * mode since we never enabled interrupts in the first place.
                 */
                esas2r_disable_chip_interrupts(a);
                esas2r_disable_heartbeat(a);

                /* wait for any VDA activity to clear before continuing */
                esas2r_write_register_dword(a, MU_DOORBELL_IN,
                                            DRBL_MSG_IFC_DOWN);
                starttime = jiffies_to_msecs(jiffies);

                while (true) {
                        doorbell =
                                esas2r_read_register_dword(a, MU_DOORBELL_OUT);
                        if (doorbell & DRBL_MSG_IFC_DOWN) {
                                esas2r_write_register_dword(a, MU_DOORBELL_OUT,
                                                            doorbell);
                                break;
                        }

                        schedule_timeout_interruptible(msecs_to_jiffies(100));

                        if ((jiffies_to_msecs(jiffies) - starttime) > 3000) {
                                esas2r_hdebug(
                                        "timeout waiting for interface down");
                                break;
                        }
                }

                /*
                 * For versions of firmware that support it tell them the driver
                 * is powering down.
                 */
                if (test_bit(AF2_VDA_POWER_DOWN, &a->flags2))
                        esas2r_power_down_notify_firmware(a);
        }

        /* Suspend I/O processing. */
        set_bit(AF_OS_RESET, &a->flags);
        set_bit(AF_DISC_PENDING, &a->flags);
        set_bit(AF_CHPRST_PENDING, &a->flags);

        esas2r_process_adapter_reset(a);

        /* Remove devices now that I/O is cleaned up. */
        a->prev_dev_cnt = esas2r_targ_db_get_tgt_cnt(a);
        esas2r_targ_db_remove_all(a, false);
}

/*
 * Perform power management processing including managing device states, adapter
 * states, interrupts, and I/O.
 */
bool esas2r_power_up(struct esas2r_adapter *a, bool init_poll)
{
        bool ret;

        clear_bit(AF_POWER_DOWN, &a->flags);
        esas2r_init_pci_cfg_space(a);
        set_bit(AF_FIRST_INIT, &a->flags);
        atomic_inc(&a->disable_cnt);

        /* reinitialize the adapter */
        ret = esas2r_check_adapter(a);
        if (!esas2r_init_adapter_hw(a, init_poll))
                ret = false;

        /* send the reset asynchronous event */
        esas2r_send_reset_ae(a, true);

        /* clear this flag after initialization. */
        clear_bit(AF_POWER_MGT, &a->flags);
        return ret;
}

bool esas2r_is_adapter_present(struct esas2r_adapter *a)
{
        if (test_bit(AF_NOT_PRESENT, &a->flags))
                return false;

        if (esas2r_read_register_dword(a, MU_DOORBELL_OUT) == 0xFFFFFFFF) {
                set_bit(AF_NOT_PRESENT, &a->flags);

                return false;
        }
        return true;
}

const char *esas2r_get_model_name(struct esas2r_adapter *a)
{
        switch (a->pcid->subsystem_device) {
        case ATTO_ESAS_R680:
                return "ATTO ExpressSAS R680";

        case ATTO_ESAS_R608:
                return "ATTO ExpressSAS R608";

        case ATTO_ESAS_R60F:
                return "ATTO ExpressSAS R60F";

        case ATTO_ESAS_R6F0:
                return "ATTO ExpressSAS R6F0";

        case ATTO_ESAS_R644:
                return "ATTO ExpressSAS R644";

        case ATTO_ESAS_R648:
                return "ATTO ExpressSAS R648";

        case ATTO_TSSC_3808:
                return "ATTO ThunderStream SC 3808D";

        case ATTO_TSSC_3808E:
                return "ATTO ThunderStream SC 3808E";

        case ATTO_TLSH_1068:
                return "ATTO ThunderLink SH 1068";
        }

        return "ATTO SAS Controller";
}

const char *esas2r_get_model_name_short(struct esas2r_adapter *a)
{
        switch (a->pcid->subsystem_device) {
        case ATTO_ESAS_R680:
                return "R680";

        case ATTO_ESAS_R608:
                return "R608";

        case ATTO_ESAS_R60F:
                return "R60F";

        case ATTO_ESAS_R6F0:
                return "R6F0";

        case ATTO_ESAS_R644:
                return "R644";

        case ATTO_ESAS_R648:
                return "R648";

        case ATTO_TSSC_3808:
                return "SC 3808D";

        case ATTO_TSSC_3808E:
                return "SC 3808E";

        case ATTO_TLSH_1068:
                return "SH 1068";
        }

        return "unknown";
}