linux/drivers/char/drm/drm_irq.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

370 lines
9.7 KiB
C

/**
* \file drm_irq.h
* IRQ support
*
* \author Rickard E. (Rik) Faith <faith@valinux.com>
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Fri Mar 19 14:30:16 1999 by faith@valinux.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
* VA LINUX SYSTEMS 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.
*/
#include "drmP.h"
#include <linux/interrupt.h> /* For task queue support */
/**
* Get interrupt from bus id.
*
* \param inode device inode.
* \param filp file pointer.
* \param cmd command.
* \param arg user argument, pointing to a drm_irq_busid structure.
* \return zero on success or a negative number on failure.
*
* Finds the PCI device with the specified bus id and gets its IRQ number.
* This IOCTL is deprecated, and will now return EINVAL for any busid not equal
* to that of the device that this DRM instance attached to.
*/
int drm_irq_by_busid(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->head->dev;
drm_irq_busid_t __user *argp = (void __user *)arg;
drm_irq_busid_t p;
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return -EINVAL;
if (copy_from_user(&p, argp, sizeof(p)))
return -EFAULT;
if ((p.busnum >> 8) != dev->pci_domain ||
(p.busnum & 0xff) != dev->pci_bus ||
p.devnum != dev->pci_slot ||
p.funcnum != dev->pci_func)
return -EINVAL;
p.irq = dev->irq;
DRM_DEBUG("%d:%d:%d => IRQ %d\n",
p.busnum, p.devnum, p.funcnum, p.irq);
if (copy_to_user(argp, &p, sizeof(p)))
return -EFAULT;
return 0;
}
/**
* Install IRQ handler.
*
* \param dev DRM device.
* \param irq IRQ number.
*
* Initializes the IRQ related data, and setups drm_device::vbl_queue. Installs the handler, calling the driver
* \c drm_driver_irq_preinstall() and \c drm_driver_irq_postinstall() functions
* before and after the installation.
*/
int drm_irq_install( drm_device_t *dev )
{
int ret;
unsigned long sh_flags=0;
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return -EINVAL;
if ( dev->irq == 0 )
return -EINVAL;
down( &dev->struct_sem );
/* Driver must have been initialized */
if ( !dev->dev_private ) {
up( &dev->struct_sem );
return -EINVAL;
}
if ( dev->irq_enabled ) {
up( &dev->struct_sem );
return -EBUSY;
}
dev->irq_enabled = 1;
up( &dev->struct_sem );
DRM_DEBUG( "%s: irq=%d\n", __FUNCTION__, dev->irq );
if (drm_core_check_feature(dev, DRIVER_IRQ_VBL)) {
init_waitqueue_head(&dev->vbl_queue);
spin_lock_init( &dev->vbl_lock );
INIT_LIST_HEAD( &dev->vbl_sigs.head );
dev->vbl_pending = 0;
}
/* Before installing handler */
dev->driver->irq_preinstall(dev);
/* Install handler */
if (drm_core_check_feature(dev, DRIVER_IRQ_SHARED))
sh_flags = SA_SHIRQ;
ret = request_irq( dev->irq, dev->driver->irq_handler,
sh_flags, dev->devname, dev );
if ( ret < 0 ) {
down( &dev->struct_sem );
dev->irq_enabled = 0;
up( &dev->struct_sem );
return ret;
}
/* After installing handler */
dev->driver->irq_postinstall(dev);
return 0;
}
/**
* Uninstall the IRQ handler.
*
* \param dev DRM device.
*
* Calls the driver's \c drm_driver_irq_uninstall() function, and stops the irq.
*/
int drm_irq_uninstall( drm_device_t *dev )
{
int irq_enabled;
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return -EINVAL;
down( &dev->struct_sem );
irq_enabled = dev->irq_enabled;
dev->irq_enabled = 0;
up( &dev->struct_sem );
if ( !irq_enabled )
return -EINVAL;
DRM_DEBUG( "%s: irq=%d\n", __FUNCTION__, dev->irq );
dev->driver->irq_uninstall(dev);
free_irq( dev->irq, dev );
return 0;
}
EXPORT_SYMBOL(drm_irq_uninstall);
/**
* IRQ control ioctl.
*
* \param inode device inode.
* \param filp file pointer.
* \param cmd command.
* \param arg user argument, pointing to a drm_control structure.
* \return zero on success or a negative number on failure.
*
* Calls irq_install() or irq_uninstall() according to \p arg.
*/
int drm_control( struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg )
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->head->dev;
drm_control_t ctl;
/* if we haven't irq we fallback for compatibility reasons - this used to be a separate function in drm_dma.h */
if ( copy_from_user( &ctl, (drm_control_t __user *)arg, sizeof(ctl) ) )
return -EFAULT;
switch ( ctl.func ) {
case DRM_INST_HANDLER:
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return 0;
if (dev->if_version < DRM_IF_VERSION(1, 2) &&
ctl.irq != dev->irq)
return -EINVAL;
return drm_irq_install( dev );
case DRM_UNINST_HANDLER:
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return 0;
return drm_irq_uninstall( dev );
default:
return -EINVAL;
}
}
/**
* Wait for VBLANK.
*
* \param inode device inode.
* \param filp file pointer.
* \param cmd command.
* \param data user argument, pointing to a drm_wait_vblank structure.
* \return zero on success or a negative number on failure.
*
* Verifies the IRQ is installed.
*
* If a signal is requested checks if this task has already scheduled the same signal
* for the same vblank sequence number - nothing to be done in
* that case. If the number of tasks waiting for the interrupt exceeds 100 the
* function fails. Otherwise adds a new entry to drm_device::vbl_sigs for this
* task.
*
* If a signal is not requested, then calls vblank_wait().
*/
int drm_wait_vblank( DRM_IOCTL_ARGS )
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->head->dev;
drm_wait_vblank_t __user *argp = (void __user *)data;
drm_wait_vblank_t vblwait;
struct timeval now;
int ret = 0;
unsigned int flags;
if (!drm_core_check_feature(dev, DRIVER_IRQ_VBL))
return -EINVAL;
if (!dev->irq)
return -EINVAL;
DRM_COPY_FROM_USER_IOCTL( vblwait, argp, sizeof(vblwait) );
switch ( vblwait.request.type & ~_DRM_VBLANK_FLAGS_MASK ) {
case _DRM_VBLANK_RELATIVE:
vblwait.request.sequence += atomic_read( &dev->vbl_received );
vblwait.request.type &= ~_DRM_VBLANK_RELATIVE;
case _DRM_VBLANK_ABSOLUTE:
break;
default:
return -EINVAL;
}
flags = vblwait.request.type & _DRM_VBLANK_FLAGS_MASK;
if ( flags & _DRM_VBLANK_SIGNAL ) {
unsigned long irqflags;
drm_vbl_sig_t *vbl_sig;
vblwait.reply.sequence = atomic_read( &dev->vbl_received );
spin_lock_irqsave( &dev->vbl_lock, irqflags );
/* Check if this task has already scheduled the same signal
* for the same vblank sequence number; nothing to be done in
* that case
*/
list_for_each_entry( vbl_sig, &dev->vbl_sigs.head, head ) {
if (vbl_sig->sequence == vblwait.request.sequence
&& vbl_sig->info.si_signo == vblwait.request.signal
&& vbl_sig->task == current)
{
spin_unlock_irqrestore( &dev->vbl_lock, irqflags );
goto done;
}
}
if ( dev->vbl_pending >= 100 ) {
spin_unlock_irqrestore( &dev->vbl_lock, irqflags );
return -EBUSY;
}
dev->vbl_pending++;
spin_unlock_irqrestore( &dev->vbl_lock, irqflags );
if ( !( vbl_sig = drm_alloc( sizeof( drm_vbl_sig_t ), DRM_MEM_DRIVER ) ) ) {
return -ENOMEM;
}
memset( (void *)vbl_sig, 0, sizeof(*vbl_sig) );
vbl_sig->sequence = vblwait.request.sequence;
vbl_sig->info.si_signo = vblwait.request.signal;
vbl_sig->task = current;
spin_lock_irqsave( &dev->vbl_lock, irqflags );
list_add_tail( (struct list_head *) vbl_sig, &dev->vbl_sigs.head );
spin_unlock_irqrestore( &dev->vbl_lock, irqflags );
} else {
if (dev->driver->vblank_wait)
ret = dev->driver->vblank_wait( dev, &vblwait.request.sequence );
do_gettimeofday( &now );
vblwait.reply.tval_sec = now.tv_sec;
vblwait.reply.tval_usec = now.tv_usec;
}
done:
DRM_COPY_TO_USER_IOCTL( argp, vblwait, sizeof(vblwait) );
return ret;
}
/**
* Send the VBLANK signals.
*
* \param dev DRM device.
*
* Sends a signal for each task in drm_device::vbl_sigs and empties the list.
*
* If a signal is not requested, then calls vblank_wait().
*/
void drm_vbl_send_signals( drm_device_t *dev )
{
struct list_head *list, *tmp;
drm_vbl_sig_t *vbl_sig;
unsigned int vbl_seq = atomic_read( &dev->vbl_received );
unsigned long flags;
spin_lock_irqsave( &dev->vbl_lock, flags );
list_for_each_safe( list, tmp, &dev->vbl_sigs.head ) {
vbl_sig = list_entry( list, drm_vbl_sig_t, head );
if ( ( vbl_seq - vbl_sig->sequence ) <= (1<<23) ) {
vbl_sig->info.si_code = vbl_seq;
send_sig_info( vbl_sig->info.si_signo, &vbl_sig->info, vbl_sig->task );
list_del( list );
drm_free( vbl_sig, sizeof(*vbl_sig), DRM_MEM_DRIVER );
dev->vbl_pending--;
}
}
spin_unlock_irqrestore( &dev->vbl_lock, flags );
}
EXPORT_SYMBOL(drm_vbl_send_signals);