root/drivers/scsi/aacraid/comminit.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *      Adaptec AAC series RAID controller driver
 *      (c) Copyright 2001 Red Hat Inc.
 *
 * based on the old aacraid driver that is..
 * Adaptec aacraid device driver for Linux.
 *
 * Copyright (c) 2000-2010 Adaptec, Inc.
 *               2010-2015 PMC-Sierra, Inc. (aacraid@pmc-sierra.com)
 *               2016-2017 Microsemi Corp. (aacraid@microsemi.com)
 *
 * Module Name:
 *  comminit.c
 *
 * Abstract: This supports the initialization of the host adapter commuication interface.
 *    This is a platform dependent module for the pci cyclone board.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/completion.h>
#include <linux/mm.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>

#include "aacraid.h"

struct aac_common aac_config = {
        .irq_mod = 1
};

static inline int aac_is_msix_mode(struct aac_dev *dev)
{
        u32 status = 0;

        if (aac_is_src(dev))
                status = src_readl(dev, MUnit.OMR);
        return (status & AAC_INT_MODE_MSIX);
}

static inline void aac_change_to_intx(struct aac_dev *dev)
{
        aac_src_access_devreg(dev, AAC_DISABLE_MSIX);
        aac_src_access_devreg(dev, AAC_ENABLE_INTX);
}

static int aac_alloc_comm(struct aac_dev *dev, void **commaddr, unsigned long commsize, unsigned long commalign)
{
        unsigned char *base;
        unsigned long size, align;
        const unsigned long fibsize = dev->max_fib_size;
        const unsigned long printfbufsiz = 256;
        unsigned long host_rrq_size, aac_init_size;
        union aac_init *init;
        dma_addr_t phys;
        unsigned long aac_max_hostphysmempages;

        if ((dev->comm_interface == AAC_COMM_MESSAGE_TYPE1) ||
                (dev->comm_interface == AAC_COMM_MESSAGE_TYPE2) ||
                (dev->comm_interface == AAC_COMM_MESSAGE_TYPE3 &&
                !dev->sa_firmware)) {
                host_rrq_size =
                        (dev->scsi_host_ptr->can_queue + AAC_NUM_MGT_FIB)
                                * sizeof(u32);
                aac_init_size = sizeof(union aac_init);
        } else if (dev->comm_interface == AAC_COMM_MESSAGE_TYPE3 &&
                dev->sa_firmware) {
                host_rrq_size = (dev->scsi_host_ptr->can_queue
                        + AAC_NUM_MGT_FIB) * sizeof(u32)  * AAC_MAX_MSIX;
                aac_init_size = sizeof(union aac_init) +
                        (AAC_MAX_HRRQ - 1) * sizeof(struct _rrq);
        } else {
                host_rrq_size = 0;
                aac_init_size = sizeof(union aac_init);
        }
        size = fibsize + aac_init_size + commsize + commalign +
                        printfbufsiz + host_rrq_size;

        base = dma_alloc_coherent(&dev->pdev->dev, size, &phys, GFP_KERNEL);
        if (base == NULL) {
                printk(KERN_ERR "aacraid: unable to create mapping.\n");
                return 0;
        }

        dev->comm_addr = (void *)base;
        dev->comm_phys = phys;
        dev->comm_size = size;

        if ((dev->comm_interface == AAC_COMM_MESSAGE_TYPE1) ||
            (dev->comm_interface == AAC_COMM_MESSAGE_TYPE2) ||
            (dev->comm_interface == AAC_COMM_MESSAGE_TYPE3)) {
                dev->host_rrq = (u32 *)(base + fibsize);
                dev->host_rrq_pa = phys + fibsize;
                memset(dev->host_rrq, 0, host_rrq_size);
        }

        dev->init = (union aac_init *)(base + fibsize + host_rrq_size);
        dev->init_pa = phys + fibsize + host_rrq_size;

        init = dev->init;

        if (dev->comm_interface == AAC_COMM_MESSAGE_TYPE3) {
                int i;
                u64 addr;

                init->r8.init_struct_revision =
                        cpu_to_le32(ADAPTER_INIT_STRUCT_REVISION_8);
                init->r8.init_flags = cpu_to_le32(INITFLAGS_NEW_COMM_SUPPORTED |
                                        INITFLAGS_DRIVER_USES_UTC_TIME |
                                        INITFLAGS_DRIVER_SUPPORTS_PM);
                init->r8.init_flags |=
                                cpu_to_le32(INITFLAGS_DRIVER_SUPPORTS_HBA_MODE);
                init->r8.rr_queue_count = cpu_to_le32(dev->max_msix);
                init->r8.max_io_size =
                        cpu_to_le32(dev->scsi_host_ptr->max_sectors << 9);
                init->r8.max_num_aif = init->r8.reserved1 =
                        init->r8.reserved2 = 0;

                for (i = 0; i < dev->max_msix; i++) {
                        addr = (u64)dev->host_rrq_pa + dev->vector_cap * i *
                                        sizeof(u32);
                        init->r8.rrq[i].host_addr_high = cpu_to_le32(
                                                upper_32_bits(addr));
                        init->r8.rrq[i].host_addr_low = cpu_to_le32(
                                                lower_32_bits(addr));
                        init->r8.rrq[i].msix_id = i;
                        init->r8.rrq[i].element_count = cpu_to_le16(
                                        (u16)dev->vector_cap);
                        init->r8.rrq[i].comp_thresh =
                                        init->r8.rrq[i].unused = 0;
                }

                pr_warn("aacraid: Comm Interface type3 enabled\n");
        } else {
                init->r7.init_struct_revision =
                        cpu_to_le32(ADAPTER_INIT_STRUCT_REVISION);
                if (dev->max_fib_size != sizeof(struct hw_fib))
                        init->r7.init_struct_revision =
                                cpu_to_le32(ADAPTER_INIT_STRUCT_REVISION_4);
                init->r7.no_of_msix_vectors = cpu_to_le32(SA_MINIPORT_REVISION);
                init->r7.fsrev = cpu_to_le32(dev->fsrev);

                /*
                 *      Adapter Fibs are the first thing allocated so that they
                 *      start page aligned
                 */
                dev->aif_base_va = (struct hw_fib *)base;

                init->r7.adapter_fibs_virtual_address = 0;
                init->r7.adapter_fibs_physical_address = cpu_to_le32((u32)phys);
                init->r7.adapter_fibs_size = cpu_to_le32(fibsize);
                init->r7.adapter_fib_align = cpu_to_le32(sizeof(struct hw_fib));

                /*
                 * number of 4k pages of host physical memory. The aacraid fw
                 * needs this number to be less than 4gb worth of pages. New
                 * firmware doesn't have any issues with the mapping system, but
                 * older Firmware did, and had *troubles* dealing with the math
                 * overloading past 32 bits, thus we must limit this field.
                 */
                aac_max_hostphysmempages =
                                dma_get_required_mask(&dev->pdev->dev) >> 12;
                if (aac_max_hostphysmempages < AAC_MAX_HOSTPHYSMEMPAGES)
                        init->r7.host_phys_mem_pages =
                                        cpu_to_le32(aac_max_hostphysmempages);
                else
                        init->r7.host_phys_mem_pages =
                                        cpu_to_le32(AAC_MAX_HOSTPHYSMEMPAGES);

                init->r7.init_flags =
                        cpu_to_le32(INITFLAGS_DRIVER_USES_UTC_TIME |
                        INITFLAGS_DRIVER_SUPPORTS_PM);
                init->r7.max_io_commands =
                        cpu_to_le32(dev->scsi_host_ptr->can_queue +
                                        AAC_NUM_MGT_FIB);
                init->r7.max_io_size =
                        cpu_to_le32(dev->scsi_host_ptr->max_sectors << 9);
                init->r7.max_fib_size = cpu_to_le32(dev->max_fib_size);
                init->r7.max_num_aif = cpu_to_le32(dev->max_num_aif);

                if (dev->comm_interface == AAC_COMM_MESSAGE) {
                        init->r7.init_flags |=
                                cpu_to_le32(INITFLAGS_NEW_COMM_SUPPORTED);
                        pr_warn("aacraid: Comm Interface enabled\n");
                } else if (dev->comm_interface == AAC_COMM_MESSAGE_TYPE1) {
                        init->r7.init_struct_revision =
                                cpu_to_le32(ADAPTER_INIT_STRUCT_REVISION_6);
                        init->r7.init_flags |=
                                cpu_to_le32(INITFLAGS_NEW_COMM_SUPPORTED |
                                INITFLAGS_NEW_COMM_TYPE1_SUPPORTED |
                                INITFLAGS_FAST_JBOD_SUPPORTED);
                        init->r7.host_rrq_addr_high =
                                cpu_to_le32(upper_32_bits(dev->host_rrq_pa));
                        init->r7.host_rrq_addr_low =
                                cpu_to_le32(lower_32_bits(dev->host_rrq_pa));
                        pr_warn("aacraid: Comm Interface type1 enabled\n");
                } else if (dev->comm_interface == AAC_COMM_MESSAGE_TYPE2) {
                        init->r7.init_struct_revision =
                                cpu_to_le32(ADAPTER_INIT_STRUCT_REVISION_7);
                        init->r7.init_flags |=
                                cpu_to_le32(INITFLAGS_NEW_COMM_SUPPORTED |
                                INITFLAGS_NEW_COMM_TYPE2_SUPPORTED |
                                INITFLAGS_FAST_JBOD_SUPPORTED);
                        init->r7.host_rrq_addr_high =
                                cpu_to_le32(upper_32_bits(dev->host_rrq_pa));
                        init->r7.host_rrq_addr_low =
                                cpu_to_le32(lower_32_bits(dev->host_rrq_pa));
                        init->r7.no_of_msix_vectors =
                                cpu_to_le32(dev->max_msix);
                        /* must be the COMM_PREFERRED_SETTINGS values */
                        pr_warn("aacraid: Comm Interface type2 enabled\n");
                }
        }

        /*
         * Increment the base address by the amount already used
         */
        base = base + fibsize + host_rrq_size + aac_init_size;
        phys = (dma_addr_t)((ulong)phys + fibsize + host_rrq_size +
                        aac_init_size);

        /*
         *      Align the beginning of Headers to commalign
         */
        align = (commalign - ((uintptr_t)(base) & (commalign - 1)));
        base = base + align;
        phys = phys + align;
        /*
         *      Fill in addresses of the Comm Area Headers and Queues
         */
        *commaddr = base;
        if (dev->comm_interface != AAC_COMM_MESSAGE_TYPE3)
                init->r7.comm_header_address = cpu_to_le32((u32)phys);
        /*
         *      Increment the base address by the size of the CommArea
         */
        base = base + commsize;
        phys = phys + commsize;
        /*
         *       Place the Printf buffer area after the Fast I/O comm area.
         */
        dev->printfbuf = (void *)base;
        if (dev->comm_interface != AAC_COMM_MESSAGE_TYPE3) {
                init->r7.printfbuf = cpu_to_le32(phys);
                init->r7.printfbufsiz = cpu_to_le32(printfbufsiz);
        }
        memset(base, 0, printfbufsiz);
        return 1;
}

static void aac_queue_init(struct aac_dev * dev, struct aac_queue * q, u32 *mem, int qsize)
{
        atomic_set(&q->numpending, 0);
        q->dev = dev;
        init_waitqueue_head(&q->cmdready);
        INIT_LIST_HEAD(&q->cmdq);
        init_waitqueue_head(&q->qfull);
        spin_lock_init(&q->lockdata);
        q->lock = &q->lockdata;
        q->headers.producer = (__le32 *)mem;
        q->headers.consumer = (__le32 *)(mem+1);
        *(q->headers.producer) = cpu_to_le32(qsize);
        *(q->headers.consumer) = cpu_to_le32(qsize);
        q->entries = qsize;
}

static bool wait_for_io_iter(struct scsi_cmnd *cmd, void *data)
{
        int *active = data;

        if (aac_priv(cmd)->owner == AAC_OWNER_FIRMWARE)
                *active = *active + 1;
        return true;
}
static void aac_wait_for_io_completion(struct aac_dev *aac)
{
        int i = 0, active;

        for (i = 60; i; --i) {

                active = 0;
                scsi_host_busy_iter(aac->scsi_host_ptr,
                                    wait_for_io_iter, &active);
                /*
                 * We can exit If all the commands are complete
                 */
                if (active == 0)
                        break;
                dev_info(&aac->pdev->dev,
                         "Wait for %d commands to complete\n", active);
                ssleep(1);
        }
        if (active)
                dev_err(&aac->pdev->dev,
                        "%d outstanding commands during shutdown\n", active);
}

/**
 *      aac_send_shutdown               -       shutdown an adapter
 *      @dev: Adapter to shutdown
 *
 *      This routine will send a VM_CloseAll (shutdown) request to the adapter.
 */

int aac_send_shutdown(struct aac_dev * dev)
{
        struct fib * fibctx;
        struct aac_close *cmd;
        int status = 0;

        if (aac_adapter_check_health(dev))
                return status;

        if (!dev->adapter_shutdown) {
                mutex_lock(&dev->ioctl_mutex);
                dev->adapter_shutdown = 1;
                mutex_unlock(&dev->ioctl_mutex);
        }

        aac_wait_for_io_completion(dev);

        fibctx = aac_fib_alloc(dev);
        if (!fibctx)
                return -ENOMEM;
        aac_fib_init(fibctx);

        cmd = (struct aac_close *) fib_data(fibctx);
        cmd->command = cpu_to_le32(VM_CloseAll);
        cmd->cid = cpu_to_le32(0xfffffffe);

        status = aac_fib_send(ContainerCommand,
                          fibctx,
                          sizeof(struct aac_close),
                          FsaNormal,
                          -2 /* Timeout silently */, 1,
                          NULL, NULL);

        if (status >= 0)
                aac_fib_complete(fibctx);
        /* FIB should be freed only after getting the response from the F/W */
        if (status != -ERESTARTSYS)
                aac_fib_free(fibctx);
        if (aac_is_src(dev) &&
             dev->msi_enabled)
                aac_set_intx_mode(dev);
        return status;
}

/**
 *      aac_comm_init   -       Initialise FSA data structures
 *      @dev:   Adapter to initialise
 *
 *      Initializes the data structures that are required for the FSA commuication
 *      interface to operate. 
 *      Returns
 *              1 - if we were able to init the commuication interface.
 *              0 - If there were errors initing. This is a fatal error.
 */
 
static int aac_comm_init(struct aac_dev * dev)
{
        unsigned long hdrsize = (sizeof(u32) * NUMBER_OF_COMM_QUEUES) * 2;
        unsigned long queuesize = sizeof(struct aac_entry) * TOTAL_QUEUE_ENTRIES;
        u32 *headers;
        struct aac_entry * queues;
        unsigned long size;
        struct aac_queue_block * comm = dev->queues;
        /*
         *      Now allocate and initialize the zone structures used as our 
         *      pool of FIB context records.  The size of the zone is based
         *      on the system memory size.  We also initialize the mutex used
         *      to protect the zone.
         */
        spin_lock_init(&dev->fib_lock);

        /*
         *      Allocate the physically contiguous space for the commuication
         *      queue headers. 
         */

        size = hdrsize + queuesize;

        if (!aac_alloc_comm(dev, (void * *)&headers, size, QUEUE_ALIGNMENT))
                return -ENOMEM;

        queues = (struct aac_entry *)(((ulong)headers) + hdrsize);

        /* Adapter to Host normal priority Command queue */ 
        comm->queue[HostNormCmdQueue].base = queues;
        aac_queue_init(dev, &comm->queue[HostNormCmdQueue], headers, HOST_NORM_CMD_ENTRIES);
        queues += HOST_NORM_CMD_ENTRIES;
        headers += 2;

        /* Adapter to Host high priority command queue */
        comm->queue[HostHighCmdQueue].base = queues;
        aac_queue_init(dev, &comm->queue[HostHighCmdQueue], headers, HOST_HIGH_CMD_ENTRIES);
    
        queues += HOST_HIGH_CMD_ENTRIES;
        headers +=2;

        /* Host to adapter normal priority command queue */
        comm->queue[AdapNormCmdQueue].base = queues;
        aac_queue_init(dev, &comm->queue[AdapNormCmdQueue], headers, ADAP_NORM_CMD_ENTRIES);
    
        queues += ADAP_NORM_CMD_ENTRIES;
        headers += 2;

        /* host to adapter high priority command queue */
        comm->queue[AdapHighCmdQueue].base = queues;
        aac_queue_init(dev, &comm->queue[AdapHighCmdQueue], headers, ADAP_HIGH_CMD_ENTRIES);
    
        queues += ADAP_HIGH_CMD_ENTRIES;
        headers += 2;

        /* adapter to host normal priority response queue */
        comm->queue[HostNormRespQueue].base = queues;
        aac_queue_init(dev, &comm->queue[HostNormRespQueue], headers, HOST_NORM_RESP_ENTRIES);
        queues += HOST_NORM_RESP_ENTRIES;
        headers += 2;

        /* adapter to host high priority response queue */
        comm->queue[HostHighRespQueue].base = queues;
        aac_queue_init(dev, &comm->queue[HostHighRespQueue], headers, HOST_HIGH_RESP_ENTRIES);
   
        queues += HOST_HIGH_RESP_ENTRIES;
        headers += 2;

        /* host to adapter normal priority response queue */
        comm->queue[AdapNormRespQueue].base = queues;
        aac_queue_init(dev, &comm->queue[AdapNormRespQueue], headers, ADAP_NORM_RESP_ENTRIES);

        queues += ADAP_NORM_RESP_ENTRIES;
        headers += 2;
        
        /* host to adapter high priority response queue */ 
        comm->queue[AdapHighRespQueue].base = queues;
        aac_queue_init(dev, &comm->queue[AdapHighRespQueue], headers, ADAP_HIGH_RESP_ENTRIES);

        comm->queue[AdapNormCmdQueue].lock = comm->queue[HostNormRespQueue].lock;
        comm->queue[AdapHighCmdQueue].lock = comm->queue[HostHighRespQueue].lock;
        comm->queue[AdapNormRespQueue].lock = comm->queue[HostNormCmdQueue].lock;
        comm->queue[AdapHighRespQueue].lock = comm->queue[HostHighCmdQueue].lock;

        return 0;
}

void aac_define_int_mode(struct aac_dev *dev)
{
        int i, msi_count, min_msix;

        msi_count = i = 0;
        /* max. vectors from GET_COMM_PREFERRED_SETTINGS */
        if (dev->max_msix == 0 ||
            dev->pdev->device == PMC_DEVICE_S6 ||
            dev->sync_mode) {
                dev->max_msix = 1;
                dev->vector_cap =
                        dev->scsi_host_ptr->can_queue +
                        AAC_NUM_MGT_FIB;
                return;
        }

        /* Don't bother allocating more MSI-X vectors than cpus */
        msi_count = min(dev->max_msix,
                (unsigned int)num_online_cpus());

        dev->max_msix = msi_count;

        if (msi_count > AAC_MAX_MSIX)
                msi_count = AAC_MAX_MSIX;

        if (msi_count > 1 &&
            pci_find_capability(dev->pdev, PCI_CAP_ID_MSIX)) {
                min_msix = 2;
                i = pci_alloc_irq_vectors(dev->pdev,
                                          min_msix, msi_count, PCI_IRQ_MSIX);
                if (i > 0) {
                        dev->msi_enabled = 1;
                        msi_count = i;
                } else {
                        dev->msi_enabled = 0;
                        dev_err(&dev->pdev->dev,
                        "MSIX not supported!! Will try INTX 0x%x.\n", i);
                }
        }

        if (!dev->msi_enabled)
                dev->max_msix = msi_count = 1;
        else {
                if (dev->max_msix > msi_count)
                        dev->max_msix = msi_count;
        }
        if (dev->comm_interface == AAC_COMM_MESSAGE_TYPE3 && dev->sa_firmware)
                dev->vector_cap = dev->scsi_host_ptr->can_queue +
                                AAC_NUM_MGT_FIB;
        else
                dev->vector_cap = (dev->scsi_host_ptr->can_queue +
                                AAC_NUM_MGT_FIB) / msi_count;

}
struct aac_dev *aac_init_adapter(struct aac_dev *dev)
{
        u32 status[5];
        struct Scsi_Host * host = dev->scsi_host_ptr;
        extern int aac_sync_mode;

        /*
         *      Check the preferred comm settings, defaults from template.
         */
        dev->management_fib_count = 0;
        spin_lock_init(&dev->manage_lock);
        spin_lock_init(&dev->sync_lock);
        spin_lock_init(&dev->iq_lock);
        dev->max_fib_size = sizeof(struct hw_fib);
        dev->sg_tablesize = host->sg_tablesize = (dev->max_fib_size
                - sizeof(struct aac_fibhdr) - sizeof(struct aac_write))
                        / sizeof(struct sgentry);
        dev->comm_interface = AAC_COMM_PRODUCER;
        dev->raw_io_interface = dev->raw_io_64 = 0;


        /*
         * Enable INTX mode, if not done already Enabled
         */
        if (aac_is_msix_mode(dev)) {
                aac_change_to_intx(dev);
                dev_info(&dev->pdev->dev, "Changed firmware to INTX mode");
        }

        if ((!aac_adapter_sync_cmd(dev, GET_ADAPTER_PROPERTIES,
                0, 0, 0, 0, 0, 0,
                status+0, status+1, status+2, status+3, status+4)) &&
                (status[0] == 0x00000001)) {
                dev->doorbell_mask = status[3];
                if (status[1] & AAC_OPT_NEW_COMM_64)
                        dev->raw_io_64 = 1;
                dev->sync_mode = aac_sync_mode;
                if (dev->a_ops.adapter_comm &&
                    (status[1] & AAC_OPT_NEW_COMM)) {
                        dev->comm_interface = AAC_COMM_MESSAGE;
                        dev->raw_io_interface = 1;
                        if ((status[1] & AAC_OPT_NEW_COMM_TYPE1)) {
                                /* driver supports TYPE1 (Tupelo) */
                                dev->comm_interface = AAC_COMM_MESSAGE_TYPE1;
                        } else if (status[1] & AAC_OPT_NEW_COMM_TYPE2) {
                                /* driver supports TYPE2 (Denali, Yosemite) */
                                dev->comm_interface = AAC_COMM_MESSAGE_TYPE2;
                        } else if (status[1] & AAC_OPT_NEW_COMM_TYPE3) {
                                /* driver supports TYPE3 (Yosemite, Thor) */
                                dev->comm_interface = AAC_COMM_MESSAGE_TYPE3;
                        } else if (status[1] & AAC_OPT_NEW_COMM_TYPE4) {
                                /* not supported TYPE - switch to sync. mode */
                                dev->comm_interface = AAC_COMM_MESSAGE_TYPE2;
                                dev->sync_mode = 1;
                        }
                }
                if ((status[1] & le32_to_cpu(AAC_OPT_EXTENDED)) &&
                        (status[4] & le32_to_cpu(AAC_EXTOPT_SA_FIRMWARE)))
                        dev->sa_firmware = 1;
                else
                        dev->sa_firmware = 0;

                if (status[4] & le32_to_cpu(AAC_EXTOPT_SOFT_RESET))
                        dev->soft_reset_support = 1;
                else
                        dev->soft_reset_support = 0;

                if ((dev->comm_interface == AAC_COMM_MESSAGE) &&
                    (status[2] > dev->base_size)) {
                        aac_adapter_ioremap(dev, 0);
                        dev->base_size = status[2];
                        if (aac_adapter_ioremap(dev, status[2])) {
                                /* remap failed, go back ... */
                                dev->comm_interface = AAC_COMM_PRODUCER;
                                if (aac_adapter_ioremap(dev, AAC_MIN_FOOTPRINT_SIZE)) {
                                        printk(KERN_WARNING
                                          "aacraid: unable to map adapter.\n");
                                        return NULL;
                                }
                        }
                }
        }
        dev->max_msix = 0;
        dev->msi_enabled = 0;
        dev->adapter_shutdown = 0;
        if ((!aac_adapter_sync_cmd(dev, GET_COMM_PREFERRED_SETTINGS,
          0, 0, 0, 0, 0, 0,
          status+0, status+1, status+2, status+3, status+4))
         && (status[0] == 0x00000001)) {
                /*
                 *      status[1] >> 16         maximum command size in KB
                 *      status[1] & 0xFFFF      maximum FIB size
                 *      status[2] >> 16         maximum SG elements to driver
                 *      status[2] & 0xFFFF      maximum SG elements from driver
                 *      status[3] & 0xFFFF      maximum number FIBs outstanding
                 */
                host->max_sectors = (status[1] >> 16) << 1;
                /* Multiple of 32 for PMC */
                dev->max_fib_size = status[1] & 0xFFE0;
                host->sg_tablesize = status[2] >> 16;
                dev->sg_tablesize = status[2] & 0xFFFF;
                if (aac_is_src(dev)) {
                        if (host->can_queue > (status[3] >> 16) -
                                        AAC_NUM_MGT_FIB)
                                host->can_queue = (status[3] >> 16) -
                                        AAC_NUM_MGT_FIB;
                } else if (host->can_queue > (status[3] & 0xFFFF) -
                                AAC_NUM_MGT_FIB)
                        host->can_queue = (status[3] & 0xFFFF) -
                                AAC_NUM_MGT_FIB;

                dev->max_num_aif = status[4] & 0xFFFF;
        }
        if (numacb > 0) {
                if (numacb < host->can_queue)
                        host->can_queue = numacb;
                else
                        pr_warn("numacb=%d ignored\n", numacb);
        }

        if (aac_is_src(dev))
                aac_define_int_mode(dev);
        /*
         *      Ok now init the communication subsystem
         */

        dev->queues = kzalloc_obj(struct aac_queue_block);
        if (dev->queues == NULL) {
                printk(KERN_ERR "Error could not allocate comm region.\n");
                return NULL;
        }

        if (aac_comm_init(dev)<0){
                kfree(dev->queues);
                dev->queues = NULL;
                return NULL;
        }
        /*
         *      Initialize the list of fibs
         */
        if (aac_fib_setup(dev) < 0) {
                kfree(dev->queues);
                dev->queues = NULL;
                return NULL;
        }
                
        INIT_LIST_HEAD(&dev->fib_list);
        INIT_LIST_HEAD(&dev->sync_fib_list);

        return dev;
}