/*
   *	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 PMC-Sierra, Inc. (aacraid@pmc-sierra.com)
   *
   * 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, 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.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; see the file COPYING.  If not, write to
   * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
   *
   * 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 <linux/semaphore.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 requesed 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.
  		 */
  		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->flags &= FIB_CONTEXT_FLAG_FASTRESP;
  			fib->callback(fib->callback_data, fib);
  		} else {
  			unsigned long flagv;
  			spin_lock_irqsave(&fib->event_lock, flagv);
  			if (!fib->done) {
  				fib->done = 1;
  				up(&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;
  	int status;
  
  	fibctx = (struct fib *)context;
  	BUG_ON(fibptr == NULL);
  	dev = fibptr->dev;
  
  	if (fibptr->hw_fib_va->header.XferState &
  	    cpu_to_le32(NoMoreAifDataAvailable)) {
  		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);
  
  	status = 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)
  ", 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 (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];
  		struct hw_fib * hwfib = fib->hw_fib_va;
  
  		/*
  		 *	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.
  		 */
  		dev->queues->queue[AdapNormCmdQueue].numpending--;
  
  		if (unlikely(fib->flags & FIB_CONTEXT_FLAG_TIMED_OUT)) {
  			aac_fib_complete(fib);
  			aac_fib_free(fib);
  			return 0;
  		}
  
  		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;
  		}
  
  		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->flags &= FIB_CONTEXT_FLAG_FASTRESP;
  			fib->callback(fib->callback_data, fib);
  		} else {
  			unsigned long flagv;
  	  		dprintk((KERN_INFO "event_wait up
  "));
  			spin_lock_irqsave(&fib->event_lock, flagv);
  			if (!fib->done) {
  				fib->done = 1;
  				up(&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);
  			}
  
  		}
  		return 0;
  	}
  }