tdfx_drv.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

static void __exit tdfx_cleanup(void)
{
	drm_device_t	      *dev = &tdfx_device;

	DRM_DEBUG("\n");

	drm_proc_cleanup();
	if (misc_deregister(&tdfx_misc)) {
		DRM_ERROR("Cannot unload module\n");
	} else {
		DRM_INFO("Module unloaded\n");
	}
	drm_ctxbitmap_cleanup(dev);
	tdfx_takedown(dev);
#if defined(CONFIG_AGP) || defined(CONFIG_AGP_MODULE)
	if (dev->agp) {
		drm_agp_uninit();
		drm_free(dev->agp, sizeof(*dev->agp), DRM_MEM_AGPLISTS);
		dev->agp = NULL;
	}
#endif
}

module_init(tdfx_init);
module_exit(tdfx_cleanup);


int tdfx_version(struct inode *inode, struct file *filp, unsigned int cmd,
		  unsigned long arg)
{
	drm_version_t version;
	int	      len;

	if (copy_from_user(&version,
			   (drm_version_t *)arg,
			   sizeof(version)))
		return -EFAULT;

#define DRM_COPY(name,value)				     \
	len = strlen(value);				     \
	if (len > name##_len) len = name##_len;		     \
	name##_len = strlen(value);			     \
	if (len && name) {				     \
		if (copy_to_user(name, value, len))	     \
			return -EFAULT;			     \
	}

	version.version_major	   = TDFX_MAJOR;
	version.version_minor	   = TDFX_MINOR;
	version.version_patchlevel = TDFX_PATCHLEVEL;

	DRM_COPY(version.name, TDFX_NAME);
	DRM_COPY(version.date, TDFX_DATE);
	DRM_COPY(version.desc, TDFX_DESC);

	if (copy_to_user((drm_version_t *)arg,
			 &version,
			 sizeof(version)))
		return -EFAULT;
	return 0;
}

int tdfx_open(struct inode *inode, struct file *filp)
{
	drm_device_t  *dev    = &tdfx_device;
	int	      retcode = 0;

	DRM_DEBUG("open_count = %d\n", dev->open_count);
	if (!(retcode = drm_open_helper(inode, filp, dev))) {
#if LINUX_VERSION_CODE < 0x020333
		MOD_INC_USE_COUNT; /* Needed before Linux 2.3.51 */
#endif
		atomic_inc(&dev->total_open);
		spin_lock(&dev->count_lock);
		if (!dev->open_count++) {
			spin_unlock(&dev->count_lock);
			return tdfx_setup(dev);
		}
		spin_unlock(&dev->count_lock);
	}
	return retcode;
}

int tdfx_release(struct inode *inode, struct file *filp)
{
	drm_file_t    *priv   = filp->private_data;
	drm_device_t  *dev;
	int	      retcode = 0;

	lock_kernel();
	dev = priv->dev;

	DRM_DEBUG("open_count = %d\n", dev->open_count);
	if (!(retcode = drm_release(inode, filp))) {
#if LINUX_VERSION_CODE < 0x020333
		MOD_DEC_USE_COUNT; /* Needed before Linux 2.3.51 */
#endif
		atomic_inc(&dev->total_close);
		spin_lock(&dev->count_lock);
		if (!--dev->open_count) {
			if (atomic_read(&dev->ioctl_count) || dev->blocked) {
				DRM_ERROR("Device busy: %d %d\n",
					  atomic_read(&dev->ioctl_count),
					  dev->blocked);
				spin_unlock(&dev->count_lock);
				unlock_kernel();
				return -EBUSY;
			}
			spin_unlock(&dev->count_lock);
			unlock_kernel();
			return tdfx_takedown(dev);
		}
		spin_unlock(&dev->count_lock);
	}

	unlock_kernel();
	return retcode;
}

/* tdfx_ioctl is called whenever a process performs an ioctl on /dev/drm. */

int tdfx_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
		unsigned long arg)
{
	int		 nr	 = DRM_IOCTL_NR(cmd);
	drm_file_t	 *priv	 = filp->private_data;
	drm_device_t	 *dev	 = priv->dev;
	int		 retcode = 0;
	drm_ioctl_desc_t *ioctl;
	drm_ioctl_t	 *func;

	atomic_inc(&dev->ioctl_count);
	atomic_inc(&dev->total_ioctl);
	++priv->ioctl_count;

	DRM_DEBUG("pid = %d, cmd = 0x%02x, nr = 0x%02x, dev 0x%x, auth = %d\n",
		  current->pid, cmd, nr, dev->device, priv->authenticated);

	if (nr >= TDFX_IOCTL_COUNT) {
		retcode = -EINVAL;
	} else {
		ioctl	  = &tdfx_ioctls[nr];
		func	  = ioctl->func;

		if (!func) {
			DRM_DEBUG("no function\n");
			retcode = -EINVAL;
		} else if ((ioctl->root_only && !capable(CAP_SYS_ADMIN))
			    || (ioctl->auth_needed && !priv->authenticated)) {
			retcode = -EACCES;
		} else {
			retcode = (func)(inode, filp, cmd, arg);
		}
	}

	atomic_dec(&dev->ioctl_count);
	return retcode;
}

int tdfx_lock(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;
        DECLARE_WAITQUEUE(entry, current);
        int               ret   = 0;
        drm_lock_t        lock;
#if DRM_DMA_HISTOGRAM
        cycles_t          start;

        dev->lck_start = start = get_cycles();
#endif

        if (copy_from_user(&lock, (drm_lock_t *)arg, sizeof(lock)))
		return -EFAULT;

        if (lock.context == DRM_KERNEL_CONTEXT) {
                DRM_ERROR("Process %d using kernel context %d\n",
                          current->pid, lock.context);
                return -EINVAL;
        }

        DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n",
                  lock.context, current->pid, dev->lock.hw_lock->lock,
                  lock.flags);

#if 0
				/* dev->queue_count == 0 right now for
                                   tdfx.  FIXME? */
        if (lock.context < 0 || lock.context >= dev->queue_count)
                return -EINVAL;
#endif

        if (!ret) {
#if 0
                if (_DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock)
                    != lock.context) {
                        long j = jiffies - dev->lock.lock_time;

                        if (lock.context == tdfx_res_ctx.handle &&
				j >= 0 && j < DRM_LOCK_SLICE) {
                                /* Can't take lock if we just had it and
                                   there is contention. */
                                DRM_DEBUG("%d (pid %d) delayed j=%d dev=%d jiffies=%d\n",
					lock.context, current->pid, j,
					dev->lock.lock_time, jiffies);
                                current->state = TASK_INTERRUPTIBLE;
				current->policy |= SCHED_YIELD;
                                schedule_timeout(DRM_LOCK_SLICE-j);
				DRM_DEBUG("jiffies=%d\n", jiffies);
                        }
                }
#endif
                add_wait_queue(&dev->lock.lock_queue, &entry);
                for (;;) {
                        current->state = TASK_INTERRUPTIBLE;
                        if (!dev->lock.hw_lock) {
                                /* Device has been unregistered */
                                ret = -EINTR;
                                break;
                        }
                        if (drm_lock_take(&dev->lock.hw_lock->lock,
                                          lock.context)) {
                                dev->lock.pid       = current->pid;
                                dev->lock.lock_time = jiffies;
                                atomic_inc(&dev->total_locks);
                                break;  /* Got lock */
                        }

                                /* Contention */
                        atomic_inc(&dev->total_sleeps);
#if 1
			current->policy |= SCHED_YIELD;
#endif
                        schedule();
                        if (signal_pending(current)) {
                                ret = -ERESTARTSYS;
                                break;
                        }
                }
                current->state = TASK_RUNNING;
                remove_wait_queue(&dev->lock.lock_queue, &entry);
        }

#if 0
	if (!ret && dev->last_context != lock.context &&
		lock.context != tdfx_res_ctx.handle &&
		dev->last_context != tdfx_res_ctx.handle) {
		add_wait_queue(&dev->context_wait, &entry);
	        current->state = TASK_INTERRUPTIBLE;
                /* PRE: dev->last_context != lock.context */
	        tdfx_context_switch(dev, dev->last_context, lock.context);
		/* POST: we will wait for the context
                   switch and will dispatch on a later call
                   when dev->last_context == lock.context
                   NOTE WE HOLD THE LOCK THROUGHOUT THIS
                   TIME! */
		current->policy |= SCHED_YIELD;
	        schedule();
	        current->state = TASK_RUNNING;
	        remove_wait_queue(&dev->context_wait, &entry);
	        if (signal_pending(current)) {
	                ret = -EINTR;
	        } else if (dev->last_context != lock.context) {
			DRM_ERROR("Context mismatch: %d %d\n",
                        	dev->last_context, lock.context);
	        }
	}
#endif

        if (!ret) {
		sigemptyset(&dev->sigmask);
		sigaddset(&dev->sigmask, SIGSTOP);
		sigaddset(&dev->sigmask, SIGTSTP);
		sigaddset(&dev->sigmask, SIGTTIN);
		sigaddset(&dev->sigmask, SIGTTOU);
		dev->sigdata.context = lock.context;
		dev->sigdata.lock    = dev->lock.hw_lock;
		block_all_signals(drm_notifier, &dev->sigdata, &dev->sigmask);

                if (lock.flags & _DRM_LOCK_READY) {
				/* Wait for space in DMA/FIFO */
		}
                if (lock.flags & _DRM_LOCK_QUIESCENT) {
				/* Make hardware quiescent */
#if 0
                        tdfx_quiescent(dev);
#endif
		}
        }

#if LINUX_VERSION_CODE < 0x020400
	if (lock.context != tdfx_res_ctx.handle) {
		current->counter = 5;
		current->priority = DEF_PRIORITY/4;
	}
#endif
        DRM_DEBUG("%d %s\n", lock.context, ret ? "interrupted" : "has lock");

#if DRM_DMA_HISTOGRAM
        atomic_inc(&dev->histo.lacq[drm_histogram_slot(get_cycles() - start)]);
#endif

        return ret;
}


int tdfx_unlock(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_lock_t	  lock;

	if (copy_from_user(&lock, (drm_lock_t *)arg, sizeof(lock)))
		return -EFAULT;

	if (lock.context == DRM_KERNEL_CONTEXT) {
		DRM_ERROR("Process %d using kernel context %d\n",
			  current->pid, lock.context);
		return -EINVAL;
	}

	DRM_DEBUG("%d frees lock (%d holds)\n",
		  lock.context,
		  _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
	atomic_inc(&dev->total_unlocks);
	if (_DRM_LOCK_IS_CONT(dev->lock.hw_lock->lock))
		atomic_inc(&dev->total_contends);
	drm_lock_transfer(dev, &dev->lock.hw_lock->lock, DRM_KERNEL_CONTEXT);
				/* FIXME: Try to send data to card here */
	if (!dev->context_flag) {
		if (drm_lock_free(dev, &dev->lock.hw_lock->lock,
				  DRM_KERNEL_CONTEXT)) {
			DRM_ERROR("\n");
		}
	}

#if LINUX_VERSION_CODE < 0x020400
	if (lock.context != tdfx_res_ctx.handle) {
		current->counter = 5;
		current->priority = DEF_PRIORITY;
	}
#endif

	unblock_all_signals();
	return 0;
}