/* dma.c -- DMA IOCTL and function support -*- linux-c -*- * Created: Fri Mar 19 14:30:16 1999 by faith@precisioninsight.com * * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas. * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: *  * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. *  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. *  * Authors: *    Rickard E. (Rik) Faith <faith@valinuxa.com> * */#define __NO_VERSION__#include "drmP.h"#include <linux/interrupt.h>	/* For task queue support */void drm_dma_setup(drm_device_t *dev){	int i;		if (!(dev->dma = drm_alloc(sizeof(*dev->dma), DRM_MEM_DRIVER))) {                printk(KERN_ERR "drm_dma_setup: can't drm_alloc dev->dma");                return;        }       	memset(dev->dma, 0, sizeof(*dev->dma));	for (i = 0; i <= DRM_MAX_ORDER; i++)		memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));}void drm_dma_takedown(drm_device_t *dev){	drm_device_dma_t  *dma = dev->dma;	int		  i, j;	if (!dma) return;					/* Clear dma buffers */	for (i = 0; i <= DRM_MAX_ORDER; i++) {		if (dma->bufs[i].seg_count) {			DRM_DEBUG("order %d: buf_count = %d,"				  " seg_count = %d\n",				  i,				  dma->bufs[i].buf_count,				  dma->bufs[i].seg_count);			for (j = 0; j < dma->bufs[i].seg_count; j++) {				drm_free_pages(dma->bufs[i].seglist[j],					       dma->bufs[i].page_order,					       DRM_MEM_DMA);			}			drm_free(dma->bufs[i].seglist,				 dma->bufs[i].seg_count				 * sizeof(*dma->bufs[0].seglist),				 DRM_MEM_SEGS);		}	   	if(dma->bufs[i].buf_count) {		   	for(j = 0; j < dma->bufs[i].buf_count; j++) {			   if(dma->bufs[i].buflist[j].dev_private) {			      drm_free(dma->bufs[i].buflist[j].dev_private,				       dma->bufs[i].buflist[j].dev_priv_size,				       DRM_MEM_BUFS);			   }			}		   	drm_free(dma->bufs[i].buflist,				 dma->bufs[i].buf_count *				 sizeof(*dma->bufs[0].buflist),				 DRM_MEM_BUFS);		   	drm_freelist_destroy(&dma->bufs[i].freelist);		}	}		if (dma->buflist) {		drm_free(dma->buflist,			 dma->buf_count * sizeof(*dma->buflist),			 DRM_MEM_BUFS);	}	if (dma->pagelist) {		drm_free(dma->pagelist,			 dma->page_count * sizeof(*dma->pagelist),			 DRM_MEM_PAGES);	}	drm_free(dev->dma, sizeof(*dev->dma), DRM_MEM_DRIVER);	dev->dma = NULL;}#if DRM_DMA_HISTOGRAM/* This is slow, but is useful for debugging. */int drm_histogram_slot(unsigned long count){	int value = DRM_DMA_HISTOGRAM_INITIAL;	int slot;	for (slot = 0;	     slot < DRM_DMA_HISTOGRAM_SLOTS;	     ++slot, value = DRM_DMA_HISTOGRAM_NEXT(value)) {		if (count < value) return slot;	}	return DRM_DMA_HISTOGRAM_SLOTS - 1;}void drm_histogram_compute(drm_device_t *dev, drm_buf_t *buf){	cycles_t queued_to_dispatched;	cycles_t dispatched_to_completed;	cycles_t completed_to_freed;	int	 q2d, d2c, c2f, q2c, q2f;		if (buf->time_queued) {		queued_to_dispatched	= (buf->time_dispatched					   - buf->time_queued);		dispatched_to_completed = (buf->time_completed					   - buf->time_dispatched);		completed_to_freed	= (buf->time_freed					   - buf->time_completed);		q2d = drm_histogram_slot(queued_to_dispatched);		d2c = drm_histogram_slot(dispatched_to_completed);		c2f = drm_histogram_slot(completed_to_freed);		q2c = drm_histogram_slot(queued_to_dispatched					 + dispatched_to_completed);		q2f = drm_histogram_slot(queued_to_dispatched					 + dispatched_to_completed					 + completed_to_freed);				atomic_inc(&dev->histo.total);		atomic_inc(&dev->histo.queued_to_dispatched[q2d]);		atomic_inc(&dev->histo.dispatched_to_completed[d2c]);		atomic_inc(&dev->histo.completed_to_freed[c2f]);				atomic_inc(&dev->histo.queued_to_completed[q2c]);		atomic_inc(&dev->histo.queued_to_freed[q2f]);	}	buf->time_queued     = 0;	buf->time_dispatched = 0;	buf->time_completed  = 0;	buf->time_freed	     = 0;}#endifvoid drm_free_buffer(drm_device_t *dev, drm_buf_t *buf){	drm_device_dma_t *dma = dev->dma;	if (!buf) return;		buf->waiting  = 0;	buf->pending  = 0;	buf->pid      = 0;	buf->used     = 0;#if DRM_DMA_HISTOGRAM	buf->time_completed = get_cycles();#endif	if (waitqueue_active(&buf->dma_wait)) {		wake_up_interruptible(&buf->dma_wait);	} else {				/* If processes are waiting, the last one				   to wake will put the buffer on the free				   list.  If no processes are waiting, we				   put the buffer on the freelist here. */		drm_freelist_put(dev, &dma->bufs[buf->order].freelist, buf);	}}void drm_reclaim_buffers(drm_device_t *dev, pid_t pid){	drm_device_dma_t *dma = dev->dma;	int		 i;	if (!dma) return;	for (i = 0; i < dma->buf_count; i++) {		if (dma->buflist[i]->pid == pid) {			switch (dma->buflist[i]->list) {			case DRM_LIST_NONE:				drm_free_buffer(dev, dma->buflist[i]);				break;			case DRM_LIST_WAIT:				dma->buflist[i]->list = DRM_LIST_RECLAIM;				break;			default:				/* Buffer already on hardware. */				break;			}		}	}}int drm_context_switch(drm_device_t *dev, int old, int new){	char	    buf[64];	drm_queue_t *q;	atomic_inc(&dev->total_ctx);	if (test_and_set_bit(0, &dev->context_flag)) {		DRM_ERROR("Reentering -- FIXME\n");		return -EBUSY;	}#if DRM_DMA_HISTOGRAM	dev->ctx_start = get_cycles();#endif		DRM_DEBUG("Context switch from %d to %d\n", old, new);	if (new >= dev->queue_count) {		clear_bit(0, &dev->context_flag);		return -EINVAL;	}	if (new == dev->last_context) {		clear_bit(0, &dev->context_flag);		return 0;	}		q = dev->queuelist[new];	atomic_inc(&q->use_count);	if (atomic_read(&q->use_count) == 1) {		atomic_dec(&q->use_count);		clear_bit(0, &dev->context_flag);		return -EINVAL;	}	if (drm_flags & DRM_FLAG_NOCTX) {		drm_context_switch_complete(dev, new);	} else {		sprintf(buf, "C %d %d\n", old, new);		drm_write_string(dev, buf);	}		atomic_dec(&q->use_count);		return 0;}int drm_context_switch_complete(drm_device_t *dev, int new){	drm_device_dma_t *dma = dev->dma;		dev->last_context = new;  /* PRE/POST: This is the _only_ writer. */	dev->last_switch  = jiffies;		if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {		DRM_ERROR("Lock isn't held after context switch\n");	}	if (!dma || !(dma->next_buffer && dma->next_buffer->while_locked)) {		if (drm_lock_free(dev, &dev->lock.hw_lock->lock,				  DRM_KERNEL_CONTEXT)) {			DRM_ERROR("Cannot free lock\n");		}	}	#if DRM_DMA_HISTOGRAM	atomic_inc(&dev->histo.ctx[drm_histogram_slot(get_cycles()						      - dev->ctx_start)]);		   #endif	clear_bit(0, &dev->context_flag);	wake_up_interruptible(&dev->context_wait);		return 0;}void drm_clear_next_buffer(drm_device_t *dev){	drm_device_dma_t *dma = dev->dma;		dma->next_buffer = NULL;	if (dma->next_queue && !DRM_BUFCOUNT(&dma->next_queue->waitlist)) {		wake_up_interruptible(&dma->next_queue->flush_queue);	}	dma->next_queue	 = NULL;}int drm_select_queue(drm_device_t *dev, void (*wrapper)(unsigned long)){	int	   i;	int	   candidate = -1;	int	   j	     = jiffies;	if (!dev) {		DRM_ERROR("No device\n");		return -1;	}	if (!dev->queuelist || !dev->queuelist[DRM_KERNEL_CONTEXT]) {				/* This only happens between the time the				   interrupt is initialized and the time				   the queues are initialized. */		return -1;	}				/* Doing "while locked" DMA? */	if (DRM_WAITCOUNT(dev, DRM_KERNEL_CONTEXT)) {		return DRM_KERNEL_CONTEXT;	}				/* If there are buffers on the last_context				   queue, and we have not been executing				   this context very long, continue to				   execute this context. */	if (dev->last_switch <= j	    && dev->last_switch + DRM_TIME_SLICE > j	    && DRM_WAITCOUNT(dev, dev->last_context)) {		return dev->last_context;	}				/* Otherwise, find a candidate */	for (i = dev->last_checked + 1; i < dev->queue_count; i++) {		if (DRM_WAITCOUNT(dev, i)) {			candidate = dev->last_checked = i;			break;		}	}	if (candidate < 0) {		for (i = 0; i < dev->queue_count; i++) {			if (DRM_WAITCOUNT(dev, i)) {				candidate = dev->last_checked = i;				break;			}		}	}	if (wrapper	    && candidate >= 0	    && candidate != dev->last_context	    && dev->last_switch <= j	    && dev->last_switch + DRM_TIME_SLICE > j) {		if (dev->timer.expires != dev->last_switch + DRM_TIME_SLICE) {			del_timer(&dev->timer);			dev->timer.function = wrapper;			dev->timer.data	    = (unsigned long)dev;			dev->timer.expires  = dev->last_switch+DRM_TIME_SLICE;			add_timer(&dev->timer);		}		return -1;	}	return candidate;}int drm_dma_enqueue(drm_device_t *dev, drm_dma_t *d){	int		  i;	drm_queue_t	  *q;	drm_buf_t	  *buf;	int		  idx;	int		  while_locked = 0;	drm_device_dma_t  *dma = dev->dma;	DECLARE_WAITQUEUE(entry, current);	DRM_DEBUG("%d\n", d->send_count);	if (d->flags & _DRM_DMA_WHILE_LOCKED) {		int context = dev->lock.hw_lock->lock;				if (!_DRM_LOCK_IS_HELD(context)) {			DRM_ERROR("No lock held during \"while locked\""				  " request\n");			return -EINVAL;		}		if (d->context != _DRM_LOCKING_CONTEXT(context)		    && _DRM_LOCKING_CONTEXT(context) != DRM_KERNEL_CONTEXT) {			DRM_ERROR("Lock held by %d while %d makes"				  " \"while locked\" request\n",				  _DRM_LOCKING_CONTEXT(context),				  d->context);			return -EINVAL;		}		q = dev->queuelist[DRM_KERNEL_CONTEXT];		while_locked = 1;	} else {		q = dev->queuelist[d->context];	}	atomic_inc(&q->use_count);	if (atomic_read(&q->block_write)) {		add_wait_queue(&q->write_queue, &entry);		atomic_inc(&q->block_count);		for (;;) {			current->state = TASK_INTERRUPTIBLE;			if (!atomic_read(&q->block_write)) break;			schedule();			if (signal_pending(current)) {				atomic_dec(&q->use_count);				remove_wait_queue(&q->write_queue, &entry);				return -EINTR;			}		}		atomic_dec(&q->block_count);		current->state = TASK_RUNNING;		remove_wait_queue(&q->write_queue, &entry);	}		for (i = 0; i < d->send_count; i++) {		idx = d->send_indices[i];		if (idx < 0 || idx >= dma->buf_count) {			atomic_dec(&q->use_count);			DRM_ERROR("Index %d (of %d max)\n",				  d->send_indices[i], dma->buf_count - 1);			return -EINVAL;		}		buf = dma->buflist[ idx ];		if (buf->pid != current->pid) {			atomic_dec(&q->use_count);			DRM_ERROR("Process %d using buffer owned by %d\n",				  current->pid, buf->pid);			return -EINVAL;		}		if (buf->list != DRM_LIST_NONE) {			atomic_dec(&q->use_count);			DRM_ERROR("Process %d using buffer %d on list %d\n",				  current->pid, buf->idx, buf->list);		}		buf->used	  = d->send_sizes[i];		buf->while_locked = while_locked;		buf->context	  = d->context;		if (!buf->used) {			DRM_ERROR("Queueing 0 length buffer\n");		}		if (buf->pending) {			atomic_dec(&q->use_count);			DRM_ERROR("Queueing pending buffer:"				  " buffer %d, offset %d\n",				  d->send_indices[i], i);			return -EINVAL;		}		if (buf->waiting) {			atomic_dec(&q->use_count);			DRM_ERROR("Queueing waiting buffer:"				  " buffer %d, offset %d\n",				  d->send_indices[i], i);			return -EINVAL;		}		buf->waiting = 1;		if (atomic_read(&q->use_count) == 1		    || atomic_read(&q->finalization)) {			drm_free_buffer(dev, buf);		} else {			drm_waitlist_put(&q->waitlist, buf);			atomic_inc(&q->total_queued);		}	}	atomic_dec(&q->use_count);		return 0;}static int drm_dma_get_buffers_of_order(drm_device_t *dev, drm_dma_t *d,					int order){	int		  i;	drm_buf_t	  *buf;	drm_device_dma_t  *dma = dev->dma;		for (i = d->granted_count; i < d->request_count; i++) {		buf = drm_freelist_get(&dma->bufs[order].freelist,				       d->flags & _DRM_DMA_WAIT);		if (!buf) break;		if (buf->pending || buf->waiting) {			DRM_ERROR("Free buffer %d in use by %d (w%d, p%d)\n",				  buf->idx,				  buf->pid,				  buf->waiting,				  buf->pending);		}		buf->pid     = current->pid;		if (copy_to_user(&d->request_indices[i],				 &buf->idx,				 sizeof(buf->idx)))			return -EFAULT;		if (copy_to_user(&d->request_sizes[i],				 &buf->total,				 sizeof(buf->total)))			return -EFAULT;		++d->granted_count;	}	return 0;}int drm_dma_get_buffers(drm_device_t *dev, drm_dma_t *dma){	int		  order;	int		  retcode = 0;	int		  tmp_order;		order = drm_order(dma->request_size);	dma->granted_count = 0;	retcode		   = drm_dma_get_buffers_of_order(dev, dma, order);	if (dma->granted_count < dma->request_count	    && (dma->flags & _DRM_DMA_SMALLER_OK)) {		for (tmp_order = order - 1;		     !retcode			     && dma->granted_count < dma->request_count			     && tmp_order >= DRM_MIN_ORDER;		     --tmp_order) {						retcode = drm_dma_get_buffers_of_order(dev, dma,							       tmp_order);		}	}	if (dma->granted_count < dma->request_count	    && (dma->flags & _DRM_DMA_LARGER_OK)) {		for (tmp_order = order + 1;		     !retcode			     && dma->granted_count < dma->request_count			     && tmp_order <= DRM_MAX_ORDER;		     ++tmp_order) {						retcode = drm_dma_get_buffers_of_order(dev, dma,							       tmp_order);		}	}	return 0;}