// 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:
 *  dpcsup.c
 *
 * Abstract: All DPC processing routines for the cyclone board occur here.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/completion.h>
#include <linux/blkdev.h>

#include "aacraid.h"

/**
 *      aac_response_normal     -       Handle command replies
 *      @q: Queue to read from
 *
 *      This DPC routine will be run when the adapter interrupts us to let us
 *      know there is a response on our normal priority queue. We will pull off
 *      all QE there are and wake up all the waiters before exiting. We will
 *      take a spinlock out on the queue before operating on it.
 */

unsigned int aac_response_normal(struct aac_queue * q)
{
        struct aac_dev * dev = q->dev;
        struct aac_entry *entry;
        struct hw_fib * hwfib;
        struct fib * fib;
        int consumed = 0;
        unsigned long flags, mflags;

        spin_lock_irqsave(q->lock, flags);
        /*
         *      Keep pulling response QEs off the response queue and waking
         *      up the waiters until there are no more QEs. We then return
         *      back to the system. If no response was requested we just
         *      deallocate the Fib here and continue.
         */
        while(aac_consumer_get(dev, q, &entry))
        {
                int fast;
                u32 index = le32_to_cpu(entry->addr);
                fast = index & 0x01;
                fib = &dev->fibs[index >> 2];
                hwfib = fib->hw_fib_va;
                
                aac_consumer_free(dev, q, HostNormRespQueue);
                /*
                 *      Remove this fib from the Outstanding I/O queue.
                 *      But only if it has not already been timed out.
                 *
                 *      If the fib has been timed out already, then just 
                 *      continue. The caller has already been notified that
                 *      the fib timed out.
                 */
                atomic_dec(&dev->queues->queue[AdapNormCmdQueue].numpending);

                if (unlikely(fib->flags & FIB_CONTEXT_FLAG_TIMED_OUT)) {
                        spin_unlock_irqrestore(q->lock, flags);
                        aac_fib_complete(fib);
                        aac_fib_free(fib);
                        spin_lock_irqsave(q->lock, flags);
                        continue;
                }
                spin_unlock_irqrestore(q->lock, flags);

                if (fast) {
                        /*
                         *      Doctor the fib
                         */
                        *(__le32 *)hwfib->data = cpu_to_le32(ST_OK);
                        hwfib->header.XferState |= cpu_to_le32(AdapterProcessed);
                        fib->flags |= FIB_CONTEXT_FLAG_FASTRESP;
                }

                FIB_COUNTER_INCREMENT(aac_config.FibRecved);

                if (hwfib->header.Command == cpu_to_le16(NuFileSystem))
                {
                        __le32 *pstatus = (__le32 *)hwfib->data;
                        if (*pstatus & cpu_to_le32(0xffff0000))
                                *pstatus = cpu_to_le32(ST_OK);
                }
                if (hwfib->header.XferState & cpu_to_le32(NoResponseExpected | Async)) 
                {
                        if (hwfib->header.XferState & cpu_to_le32(NoResponseExpected)) {
                                FIB_COUNTER_INCREMENT(aac_config.NoResponseRecved);
                        } else {
                                FIB_COUNTER_INCREMENT(aac_config.AsyncRecved);
                        }
                        /*
                         *      NOTE:  we cannot touch the fib after this
                         *          call, because it may have been deallocated.
                         */
                        fib->callback(fib->callback_data, fib);
                } else {
                        unsigned long flagv;
                        spin_lock_irqsave(&fib->event_lock, flagv);
                        if (!fib->done) {
                                fib->done = 1;
                                complete(&fib->event_wait);
                        }
                        spin_unlock_irqrestore(&fib->event_lock, flagv);

                        spin_lock_irqsave(&dev->manage_lock, mflags);
                        dev->management_fib_count--;
                        spin_unlock_irqrestore(&dev->manage_lock, mflags);

                        FIB_COUNTER_INCREMENT(aac_config.NormalRecved);
                        if (fib->done == 2) {
                                spin_lock_irqsave(&fib->event_lock, flagv);
                                fib->done = 0;
                                spin_unlock_irqrestore(&fib->event_lock, flagv);
                                aac_fib_complete(fib);
                                aac_fib_free(fib);
                        }
                }
                consumed++;
                spin_lock_irqsave(q->lock, flags);
        }

        if (consumed > aac_config.peak_fibs)
                aac_config.peak_fibs = consumed;
        if (consumed == 0) 
                aac_config.zero_fibs++;

        spin_unlock_irqrestore(q->lock, flags);
        return 0;
}


/**
 *      aac_command_normal      -       handle commands
 *      @q: queue to process
 *
 *      This DPC routine will be queued when the adapter interrupts us to 
 *      let us know there is a command on our normal priority queue. We will 
 *      pull off all QE there are and wake up all the waiters before exiting.
 *      We will take a spinlock out on the queue before operating on it.
 */
 
unsigned int aac_command_normal(struct aac_queue *q)
{
        struct aac_dev * dev = q->dev;
        struct aac_entry *entry;
        unsigned long flags;

        spin_lock_irqsave(q->lock, flags);

        /*
         *      Keep pulling response QEs off the response queue and waking
         *      up the waiters until there are no more QEs. We then return
         *      back to the system.
         */
        while(aac_consumer_get(dev, q, &entry))
        {
                struct fib fibctx;
                struct hw_fib * hw_fib;
                u32 index;
                struct fib *fib = &fibctx;
                
                index = le32_to_cpu(entry->addr) / sizeof(struct hw_fib);
                hw_fib = &dev->aif_base_va[index];
                
                /*
                 *      Allocate a FIB at all costs. For non queued stuff
                 *      we can just use the stack so we are happy. We need
                 *      a fib object in order to manage the linked lists
                 */
                if (dev->aif_thread)
                        if((fib = kmalloc(sizeof(struct fib), GFP_ATOMIC)) == NULL)
                                fib = &fibctx;
                
                memset(fib, 0, sizeof(struct fib));
                INIT_LIST_HEAD(&fib->fiblink);
                fib->type = FSAFS_NTC_FIB_CONTEXT;
                fib->size = sizeof(struct fib);
                fib->hw_fib_va = hw_fib;
                fib->data = hw_fib->data;
                fib->dev = dev;
                
                                
                if (dev->aif_thread && fib != &fibctx) {
                        list_add_tail(&fib->fiblink, &q->cmdq);
                        aac_consumer_free(dev, q, HostNormCmdQueue);
                        wake_up_interruptible(&q->cmdready);
                } else {
                        aac_consumer_free(dev, q, HostNormCmdQueue);
                        spin_unlock_irqrestore(q->lock, flags);
                        /*
                         *      Set the status of this FIB
                         */
                        *(__le32 *)hw_fib->data = cpu_to_le32(ST_OK);
                        aac_fib_adapter_complete(fib, sizeof(u32));
                        spin_lock_irqsave(q->lock, flags);
                }               
        }
        spin_unlock_irqrestore(q->lock, flags);
        return 0;
}

/*
 *
 * aac_aif_callback
 * @context: the context set in the fib - here it is scsi cmd
 * @fibptr: pointer to the fib
 *
 * Handles the AIFs - new method (SRC)
 *
 */

static void aac_aif_callback(void *context, struct fib * fibptr)
{
        struct fib *fibctx;
        struct aac_dev *dev;
        struct aac_aifcmd *cmd;

        fibctx = (struct fib *)context;
        BUG_ON(fibptr == NULL);
        dev = fibptr->dev;

        if ((fibptr->hw_fib_va->header.XferState &
            cpu_to_le32(NoMoreAifDataAvailable)) ||
                dev->sa_firmware) {
                aac_fib_complete(fibptr);
                aac_fib_free(fibptr);
                return;
        }

        aac_intr_normal(dev, 0, 1, 0, fibptr->hw_fib_va);

        aac_fib_init(fibctx);
        cmd = (struct aac_aifcmd *) fib_data(fibctx);
        cmd->command = cpu_to_le32(AifReqEvent);

        aac_fib_send(AifRequest,
                fibctx,
                sizeof(struct hw_fib)-sizeof(struct aac_fibhdr),
                FsaNormal,
                0, 1,
                (fib_callback)aac_aif_callback, fibctx);
}


/*
 *      aac_intr_normal -       Handle command replies
 *      @dev: Device
 *      @index: completion reference
 *
 *      This DPC routine will be run when the adapter interrupts us to let us
 *      know there is a response on our normal priority queue. We will pull off
 *      all QE there are and wake up all the waiters before exiting.
 */
unsigned int aac_intr_normal(struct aac_dev *dev, u32 index, int isAif,
        int isFastResponse, struct hw_fib *aif_fib)
{
        unsigned long mflags;
        dprintk((KERN_INFO "aac_intr_normal(%p,%x)\n", dev, index));
        if (isAif == 1) {       /* AIF - common */
                struct hw_fib * hw_fib;
                struct fib * fib;
                struct aac_queue *q = &dev->queues->queue[HostNormCmdQueue];
                unsigned long flags;

                /*
                 *      Allocate a FIB. For non queued stuff we can just use
                 * the stack so we are happy. We need a fib object in order to
                 * manage the linked lists.
                 */
                if ((!dev->aif_thread)
                 || (!(fib = kzalloc(sizeof(struct fib),GFP_ATOMIC))))
                        return 1;
                if (!(hw_fib = kzalloc(sizeof(struct hw_fib),GFP_ATOMIC))) {
                        kfree (fib);
                        return 1;
                }
                if (dev->sa_firmware) {
                        fib->hbacmd_size = index;       /* store event type */
                } else if (aif_fib != NULL) {
                        memcpy(hw_fib, aif_fib, sizeof(struct hw_fib));
                } else {
                        memcpy(hw_fib, (struct hw_fib *)
                                (((uintptr_t)(dev->regs.sa)) + index),
                                sizeof(struct hw_fib));
                }
                INIT_LIST_HEAD(&fib->fiblink);
                fib->type = FSAFS_NTC_FIB_CONTEXT;
                fib->size = sizeof(struct fib);
                fib->hw_fib_va = hw_fib;
                fib->data = hw_fib->data;
                fib->dev = dev;
        
                spin_lock_irqsave(q->lock, flags);
                list_add_tail(&fib->fiblink, &q->cmdq);
                wake_up_interruptible(&q->cmdready);
                spin_unlock_irqrestore(q->lock, flags);
                return 1;
        } else if (isAif == 2) {        /* AIF - new (SRC) */
                struct fib *fibctx;
                struct aac_aifcmd *cmd;

                fibctx = aac_fib_alloc(dev);
                if (!fibctx)
                        return 1;
                aac_fib_init(fibctx);

                cmd = (struct aac_aifcmd *) fib_data(fibctx);
                cmd->command = cpu_to_le32(AifReqEvent);

                return aac_fib_send(AifRequest,
                        fibctx,
                        sizeof(struct hw_fib)-sizeof(struct aac_fibhdr),
                        FsaNormal,
                        0, 1,
                        (fib_callback)aac_aif_callback, fibctx);
        } else {
                struct fib *fib = &dev->fibs[index];
                int start_callback = 0;

                /*
                 *      Remove this fib from the Outstanding I/O queue.
                 *      But only if it has not already been timed out.
                 *
                 *      If the fib has been timed out already, then just 
                 *      continue. The caller has already been notified that
                 *      the fib timed out.
                 */
                atomic_dec(&dev->queues->queue[AdapNormCmdQueue].numpending);

                if (unlikely(fib->flags & FIB_CONTEXT_FLAG_TIMED_OUT)) {
                        aac_fib_complete(fib);
                        aac_fib_free(fib);
                        return 0;
                }

                FIB_COUNTER_INCREMENT(aac_config.FibRecved);

                if (fib->flags & FIB_CONTEXT_FLAG_NATIVE_HBA) {

                        if (isFastResponse)
                                fib->flags |= FIB_CONTEXT_FLAG_FASTRESP;

                        if (fib->callback) {
                                start_callback = 1;
                        } else {
                                unsigned long flagv;
                                int completed = 0;

                                dprintk((KERN_INFO "event_wait up\n"));
                                spin_lock_irqsave(&fib->event_lock, flagv);
                                if (fib->done == 2) {
                                        fib->done = 1;
                                        completed = 1;
                                } else {
                                        fib->done = 1;
                                        complete(&fib->event_wait);
                                }
                                spin_unlock_irqrestore(&fib->event_lock, flagv);

                                spin_lock_irqsave(&dev->manage_lock, mflags);
                                dev->management_fib_count--;
                                spin_unlock_irqrestore(&dev->manage_lock,
                                        mflags);

                                FIB_COUNTER_INCREMENT(aac_config.NativeRecved);
                                if (completed)
                                        aac_fib_complete(fib);
                        }
                } else {
                        struct hw_fib *hwfib = fib->hw_fib_va;

                        if (isFastResponse) {
                                /* Doctor the fib */
                                *(__le32 *)hwfib->data = cpu_to_le32(ST_OK);
                                hwfib->header.XferState |=
                                        cpu_to_le32(AdapterProcessed);
                                fib->flags |= FIB_CONTEXT_FLAG_FASTRESP;
                        }

                        if (hwfib->header.Command ==
                                cpu_to_le16(NuFileSystem)) {
                                __le32 *pstatus = (__le32 *)hwfib->data;

                                if (*pstatus & cpu_to_le32(0xffff0000))
                                        *pstatus = cpu_to_le32(ST_OK);
                        }
                        if (hwfib->header.XferState &
                                cpu_to_le32(NoResponseExpected | Async)) {
                                if (hwfib->header.XferState & cpu_to_le32(
                                        NoResponseExpected)) {
                                        FIB_COUNTER_INCREMENT(
                                                aac_config.NoResponseRecved);
                                } else {
                                        FIB_COUNTER_INCREMENT(
                                                aac_config.AsyncRecved);
                                }
                                start_callback = 1;
                        } else {
                                unsigned long flagv;
                                int completed = 0;

                                dprintk((KERN_INFO "event_wait up\n"));
                                spin_lock_irqsave(&fib->event_lock, flagv);
                                if (fib->done == 2) {
                                        fib->done = 1;
                                        completed = 1;
                                } else {
                                        fib->done = 1;
                                        complete(&fib->event_wait);
                                }
                                spin_unlock_irqrestore(&fib->event_lock, flagv);

                                spin_lock_irqsave(&dev->manage_lock, mflags);
                                dev->management_fib_count--;
                                spin_unlock_irqrestore(&dev->manage_lock,
                                        mflags);

                                FIB_COUNTER_INCREMENT(aac_config.NormalRecved);
                                if (completed)
                                        aac_fib_complete(fib);
                        }
                }


                if (start_callback) {
                        /*
                         * NOTE:  we cannot touch the fib after this
                         *  call, because it may have been deallocated.
                         */
                        if (likely(fib->callback && fib->callback_data)) {
                                fib->callback(fib->callback_data, fib);
                        } else {
                                aac_fib_complete(fib);
                                aac_fib_free(fib);
                        }

                }
                return 0;
        }
}