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/* 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;
}
#endif
void 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;
}
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