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/* gamma_dma.c -- DMA support for GMX 2000 -*- linux-c -*-
* Created: Fri Mar 19 14:30:16 1999 by faith@precisioninsight.com
*
* Copyright 1999 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@valinux.com>
*
*/
#define __NO_VERSION__
#include "gamma.h"
#include "drmP.h"
#include "gamma_drv.h"
#include <linux/interrupt.h> /* For task queue support */
#include <linux/delay.h>
static inline void gamma_dma_dispatch(drm_device_t *dev, unsigned long address,
unsigned long length)
{
drm_gamma_private_t *dev_priv =
(drm_gamma_private_t *)dev->dev_private;
GAMMA_WRITE(GAMMA_DMAADDRESS, virt_to_phys((void *)address));
while (GAMMA_READ(GAMMA_GCOMMANDSTATUS) != 4)
;
GAMMA_WRITE(GAMMA_DMACOUNT, length / 4);
}
void gamma_dma_quiescent_single(drm_device_t *dev)
{
drm_gamma_private_t *dev_priv =
(drm_gamma_private_t *)dev->dev_private;
while (GAMMA_READ(GAMMA_DMACOUNT))
;
while (GAMMA_READ(GAMMA_INFIFOSPACE) < 3)
;
GAMMA_WRITE(GAMMA_FILTERMODE, 1 << 10);
GAMMA_WRITE(GAMMA_SYNC, 0);
do {
while (!GAMMA_READ(GAMMA_OUTFIFOWORDS))
;
} while (GAMMA_READ(GAMMA_OUTPUTFIFO) != GAMMA_SYNC_TAG);
}
void gamma_dma_quiescent_dual(drm_device_t *dev)
{
drm_gamma_private_t *dev_priv =
(drm_gamma_private_t *)dev->dev_private;
while (GAMMA_READ(GAMMA_DMACOUNT))
;
while (GAMMA_READ(GAMMA_INFIFOSPACE) < 3)
;
GAMMA_WRITE(GAMMA_BROADCASTMASK, 3);
GAMMA_WRITE(GAMMA_FILTERMODE, 1 << 10);
GAMMA_WRITE(GAMMA_SYNC, 0);
/* Read from first MX */
do {
while (!GAMMA_READ(GAMMA_OUTFIFOWORDS))
;
} while (GAMMA_READ(GAMMA_OUTPUTFIFO) != GAMMA_SYNC_TAG);
/* Read from second MX */
do {
while (!GAMMA_READ(GAMMA_OUTFIFOWORDS + 0x10000))
;
} while (GAMMA_READ(GAMMA_OUTPUTFIFO + 0x10000) != GAMMA_SYNC_TAG);
}
void gamma_dma_ready(drm_device_t *dev)
{
drm_gamma_private_t *dev_priv =
(drm_gamma_private_t *)dev->dev_private;
while (GAMMA_READ(GAMMA_DMACOUNT))
;
}
static inline int gamma_dma_is_ready(drm_device_t *dev)
{
drm_gamma_private_t *dev_priv =
(drm_gamma_private_t *)dev->dev_private;
return !GAMMA_READ(GAMMA_DMACOUNT);
}
void gamma_dma_service(int irq, void *device, struct pt_regs *regs)
{
drm_device_t *dev = (drm_device_t *)device;
drm_device_dma_t *dma = dev->dma;
drm_gamma_private_t *dev_priv =
(drm_gamma_private_t *)dev->dev_private;
atomic_inc(&dev->counts[6]); /* _DRM_STAT_IRQ */
GAMMA_WRITE(GAMMA_GDELAYTIMER, 0xc350/2); /* 0x05S */
GAMMA_WRITE(GAMMA_GCOMMANDINTFLAGS, 8);
GAMMA_WRITE(GAMMA_GINTFLAGS, 0x2001);
if (gamma_dma_is_ready(dev)) {
/* Free previous buffer */
if (test_and_set_bit(0, &dev->dma_flag)) return;
if (dma->this_buffer) {
gamma_free_buffer(dev, dma->this_buffer);
dma->this_buffer = NULL;
}
clear_bit(0, &dev->dma_flag);
/* Dispatch new buffer */
queue_task(&dev->tq, &tq_immediate);
mark_bh(IMMEDIATE_BH);
}
}
/* Only called by gamma_dma_schedule. */
static int gamma_do_dma(drm_device_t *dev, int locked)
{
unsigned long address;
unsigned long length;
drm_buf_t *buf;
int retcode = 0;
drm_device_dma_t *dma = dev->dma;
#if DRM_DMA_HISTOGRAM
cycles_t dma_start, dma_stop;
#endif
if (test_and_set_bit(0, &dev->dma_flag)) return -EBUSY;
#if DRM_DMA_HISTOGRAM
dma_start = get_cycles();
#endif
if (!dma->next_buffer) {
DRM_ERROR("No next_buffer\n");
clear_bit(0, &dev->dma_flag);
return -EINVAL;
}
buf = dma->next_buffer;
address = (unsigned long)buf->address;
length = buf->used;
DRM_DEBUG("context %d, buffer %d (%ld bytes)\n",
buf->context, buf->idx, length);
if (buf->list == DRM_LIST_RECLAIM) {
gamma_clear_next_buffer(dev);
gamma_free_buffer(dev, buf);
clear_bit(0, &dev->dma_flag);
return -EINVAL;
}
if (!length) {
DRM_ERROR("0 length buffer\n");
gamma_clear_next_buffer(dev);
gamma_free_buffer(dev, buf);
clear_bit(0, &dev->dma_flag);
return 0;
}
if (!gamma_dma_is_ready(dev)) {
clear_bit(0, &dev->dma_flag);
return -EBUSY;
}
if (buf->while_locked) {
if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
DRM_ERROR("Dispatching buffer %d from pid %d"
" \"while locked\", but no lock held\n",
buf->idx, buf->pid);
}
} else {
if (!locked && !gamma_lock_take(&dev->lock.hw_lock->lock,
DRM_KERNEL_CONTEXT)) {
clear_bit(0, &dev->dma_flag);
return -EBUSY;
}
}
if (dev->last_context != buf->context
&& !(dev->queuelist[buf->context]->flags
& _DRM_CONTEXT_PRESERVED)) {
/* PRE: dev->last_context != buf->context */
if (DRM(context_switch)(dev, dev->last_context,
buf->context)) {
DRM(clear_next_buffer)(dev);
DRM(free_buffer)(dev, buf);
}
retcode = -EBUSY;
goto cleanup;
/* POST: we will wait for the context
switch and will dispatch on a later call
when dev->last_context == buf->context.
NOTE WE HOLD THE LOCK THROUGHOUT THIS
TIME! */
}
gamma_clear_next_buffer(dev);
buf->pending = 1;
buf->waiting = 0;
buf->list = DRM_LIST_PEND;
#if DRM_DMA_HISTOGRAM
buf->time_dispatched = get_cycles();
#endif
gamma_dma_dispatch(dev, address, length);
gamma_free_buffer(dev, dma->this_buffer);
dma->this_buffer = buf;
atomic_inc(&dev->counts[7]); /* _DRM_STAT_DMA */
atomic_add(length, &dev->counts[8]); /* _DRM_STAT_PRIMARY */
if (!buf->while_locked && !dev->context_flag && !locked) {
if (gamma_lock_free(dev, &dev->lock.hw_lock->lock,
DRM_KERNEL_CONTEXT)) {
DRM_ERROR("\n");
}
}
cleanup:
clear_bit(0, &dev->dma_flag);
#if DRM_DMA_HISTOGRAM
dma_stop = get_cycles();
atomic_inc(&dev->histo.dma[gamma_histogram_slot(dma_stop - dma_start)]);
#endif
return retcode;
}
static void gamma_dma_timer_bh(unsigned long dev)
{
gamma_dma_schedule((drm_device_t *)dev, 0);
}
void gamma_dma_immediate_bh(void *dev)
{
gamma_dma_schedule(dev, 0);
}
int gamma_dma_schedule(drm_device_t *dev, int locked)
{
int next;
drm_queue_t *q;
drm_buf_t *buf;
int retcode = 0;
int processed = 0;
int missed;
int expire = 20;
drm_device_dma_t *dma = dev->dma;
#if DRM_DMA_HISTOGRAM
cycles_t schedule_start;
#endif
if (test_and_set_bit(0, &dev->interrupt_flag)) {
/* Not reentrant */
atomic_inc(&dev->counts[10]); /* _DRM_STAT_MISSED */
return -EBUSY;
}
missed = atomic_read(&dev->counts[10]);
#if DRM_DMA_HISTOGRAM
schedule_start = get_cycles();
#endif
again:
if (dev->context_flag) {
clear_bit(0, &dev->interrupt_flag);
return -EBUSY;
}
if (dma->next_buffer) {
/* Unsent buffer that was previously
selected, but that couldn't be sent
because the lock could not be obtained
or the DMA engine wasn't ready. Try
again. */
if (!(retcode = gamma_do_dma(dev, locked))) ++processed;
} else {
do {
next = gamma_select_queue(dev, gamma_dma_timer_bh);
if (next >= 0) {
q = dev->queuelist[next];
buf = gamma_waitlist_get(&q->waitlist);
dma->next_buffer = buf;
dma->next_queue = q;
if (buf && buf->list == DRM_LIST_RECLAIM) {
gamma_clear_next_buffer(dev);
gamma_free_buffer(dev, buf);
}
}
} while (next >= 0 && !dma->next_buffer);
if (dma->next_buffer) {
if (!(retcode = gamma_do_dma(dev, locked))) {
++processed;
}
}
}
if (--expire) {
if (missed != atomic_read(&dev->counts[10])) {
if (gamma_dma_is_ready(dev)) goto again;
}
if (processed && gamma_dma_is_ready(dev)) {
processed = 0;
goto again;
}
}
clear_bit(0, &dev->interrupt_flag);
#if DRM_DMA_HISTOGRAM
atomic_inc(&dev->histo.schedule[gamma_histogram_slot(get_cycles()
- schedule_start)]);
#endif
return retcode;
}
static int gamma_dma_priority(drm_device_t *dev, drm_dma_t *d)
{
unsigned long address;
unsigned long length;
int must_free = 0;
int retcode = 0;
int i;
int idx;
drm_buf_t *buf;
drm_buf_t *last_buf = NULL;
drm_device_dma_t *dma = dev->dma;
DECLARE_WAITQUEUE(entry, current);
/* Turn off interrupt handling */
while (test_and_set_bit(0, &dev->interrupt_flag)) {
schedule();
if (signal_pending(current)) return -EINTR;
}
if (!(d->flags & _DRM_DMA_WHILE_LOCKED)) {
while (!gamma_lock_take(&dev->lock.hw_lock->lock,
DRM_KERNEL_CONTEXT)) {
schedule();
if (signal_pending(current)) {
clear_bit(0, &dev->interrupt_flag);
return -EINTR;
}
}
++must_free;
}
for (i = 0; i < d->send_count; i++) {
idx = d->send_indices[i];
if (idx < 0 || idx >= dma->buf_count) {
DRM_ERROR("Index %d (of %d max)\n",
d->send_indices[i], dma->buf_count - 1);
continue;
}
buf = dma->buflist[ idx ];
if (buf->pid != current->pid) {
DRM_ERROR("Process %d using buffer owned by %d\n",
current->pid, buf->pid);
retcode = -EINVAL;
goto cleanup;
}
if (buf->list != DRM_LIST_NONE) {
DRM_ERROR("Process %d using %d's buffer on list %d\n",
current->pid, buf->pid, buf->list);
retcode = -EINVAL;
goto cleanup;
}
/* This isn't a race condition on
buf->list, since our concern is the
buffer reclaim during the time the
process closes the /dev/drm? handle, so
it can't also be doing DMA. */
buf->list = DRM_LIST_PRIO;
buf->used = d->send_sizes[i];
buf->context = d->context;
buf->while_locked = d->flags & _DRM_DMA_WHILE_LOCKED;
address = (unsigned long)buf->address;
length = buf->used;
if (!length) {
DRM_ERROR("0 length buffer\n");
}
if (buf->pending) {
DRM_ERROR("Sending pending buffer:"
" buffer %d, offset %d\n",
d->send_indices[i], i);
retcode = -EINVAL;
goto cleanup;
}
if (buf->waiting) {
DRM_ERROR("Sending waiting buffer:"
" buffer %d, offset %d\n",
d->send_indices[i], i);
retcode = -EINVAL;
goto cleanup;
}
buf->pending = 1;
if (dev->last_context != buf->context
&& !(dev->queuelist[buf->context]->flags
& _DRM_CONTEXT_PRESERVED)) {
add_wait_queue(&dev->context_wait, &entry);
current->state = TASK_INTERRUPTIBLE;
/* PRE: dev->last_context != buf->context */
DRM(context_switch)(dev, dev->last_context,
buf->context);
/* POST: we will wait for the context
switch and will dispatch on a later call
when dev->last_context == buf->context.
NOTE WE HOLD THE LOCK THROUGHOUT THIS
TIME! */
schedule();
current->state = TASK_RUNNING;
remove_wait_queue(&dev->context_wait, &entry);
if (signal_pending(current)) {
retcode = -EINTR;
goto cleanup;
}
if (dev->last_context != buf->context) {
DRM_ERROR("Context mismatch: %d %d\n",
dev->last_context,
buf->context);
}
}
#if DRM_DMA_HISTOGRAM
buf->time_queued = get_cycles();
buf->time_dispatched = buf->time_queued;
#endif
gamma_dma_dispatch(dev, address, length);
atomic_inc(&dev->counts[9]); /* _DRM_STAT_SPECIAL */
atomic_add(length, &dev->counts[8]); /* _DRM_STAT_PRIMARY */
if (last_buf) {
gamma_free_buffer(dev, last_buf);
}
last_buf = buf;
}
cleanup:
if (last_buf) {
gamma_dma_ready(dev);
gamma_free_buffer(dev, last_buf);
}
if (must_free && !dev->context_flag) {
if (gamma_lock_free(dev, &dev->lock.hw_lock->lock,
DRM_KERNEL_CONTEXT)) {
DRM_ERROR("\n");
}
}
clear_bit(0, &dev->interrupt_flag);
return retcode;
}
static int gamma_dma_send_buffers(drm_device_t *dev, drm_dma_t *d)
{
DECLARE_WAITQUEUE(entry, current);
drm_buf_t *last_buf = NULL;
int retcode = 0;
drm_device_dma_t *dma = dev->dma;
if (d->flags & _DRM_DMA_BLOCK) {
last_buf = dma->buflist[d->send_indices[d->send_count-1]];
add_wait_queue(&last_buf->dma_wait, &entry);
}
if ((retcode = gamma_dma_enqueue(dev, d))) {
if (d->flags & _DRM_DMA_BLOCK)
remove_wait_queue(&last_buf->dma_wait, &entry);
return retcode;
}
gamma_dma_schedule(dev, 0);
if (d->flags & _DRM_DMA_BLOCK) {
DRM_DEBUG("%d waiting\n", current->pid);
for (;;) {
current->state = TASK_INTERRUPTIBLE;
if (!last_buf->waiting && !last_buf->pending)
break; /* finished */
schedule();
if (signal_pending(current)) {
retcode = -EINTR; /* Can't restart */
break;
}
}
current->state = TASK_RUNNING;
DRM_DEBUG("%d running\n", current->pid);
remove_wait_queue(&last_buf->dma_wait, &entry);
if (!retcode
|| (last_buf->list==DRM_LIST_PEND && !last_buf->pending)) {
if (!waitqueue_active(&last_buf->dma_wait)) {
gamma_free_buffer(dev, last_buf);
}
}
if (retcode) {
DRM_ERROR("ctx%d w%d p%d c%d i%d l%d %d/%d\n",
d->context,
last_buf->waiting,
last_buf->pending,
DRM_WAITCOUNT(dev, d->context),
last_buf->idx,
last_buf->list,
last_buf->pid,
current->pid);
}
}
return retcode;
}
int gamma_dma(struct inode *inode, struct file *filp, unsigned int cmd,
unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_device_dma_t *dma = dev->dma;
int retcode = 0;
drm_dma_t d;
if (copy_from_user(&d, (drm_dma_t *)arg, sizeof(d)))
return -EFAULT;
if (d.send_count < 0 || d.send_count > dma->buf_count) {
DRM_ERROR("Process %d trying to send %d buffers (of %d max)\n",
current->pid, d.send_count, dma->buf_count);
return -EINVAL;
}
if (d.request_count < 0 || d.request_count > dma->buf_count) {
DRM_ERROR("Process %d trying to get %d buffers (of %d max)\n",
current->pid, d.request_count, dma->buf_count);
return -EINVAL;
}
if (d.send_count) {
if (d.flags & _DRM_DMA_PRIORITY)
retcode = gamma_dma_priority(dev, &d);
else
retcode = gamma_dma_send_buffers(dev, &d);
}
d.granted_count = 0;
if (!retcode && d.request_count) {
retcode = gamma_dma_get_buffers(dev, &d);
}
DRM_DEBUG("%d returning, granted = %d\n",
current->pid, d.granted_count);
if (copy_to_user((drm_dma_t *)arg, &d, sizeof(d)))
return -EFAULT;
return retcode;
}
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