drivers/char/drm/mga_irq.c

   1 /* mga_irq.c -- IRQ handling for radeon -*- linux-c -*-
   2  *
   3  * Copyright (C) The Weather Channel, Inc.  2002.  All Rights Reserved.
   4  *
   5  * The Weather Channel (TM) funded Tungsten Graphics to develop the
   6  * initial release of the Radeon 8500 driver under the XFree86 license.
   7  * This notice must be preserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice (including the next
  17  * paragraph) shall be included in all copies or substantial portions of the
  18  * Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  23  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  24  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  25  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  26  * DEALINGS IN THE SOFTWARE.
  27  *
  28  * Authors:
  29  *    Keith Whitwell <keith@tungstengraphics.com>
  30  *    Eric Anholt <anholt@FreeBSD.org>
  31  */
  32
  33 #include "drmP.h"
  34 #include "drm.h"
  35 #include "mga_drm.h"
  36 #include "mga_drv.h"
  37
  38 irqreturn_t mga_driver_irq_handler( DRM_IRQ_ARGS )
  39 {
  40         drm_device_t *dev = (drm_device_t *) arg;
  41         drm_mga_private_t *dev_priv =
  42            (drm_mga_private_t *)dev->dev_private;
  43         int status;
  44
  45         status = MGA_READ( MGA_STATUS );
  46
  47         /* VBLANK interrupt */
  48         if ( status & MGA_VLINEPEN ) {
  49                 MGA_WRITE( MGA_ICLEAR, MGA_VLINEICLR );
  50                 atomic_inc(&dev->vbl_received);
  51                 DRM_WAKEUP(&dev->vbl_queue);
  52                 drm_vbl_send_signals( dev );
  53                 return IRQ_HANDLED;
  54         }
  55         return IRQ_NONE;
  56 }
  57
  58 int mga_driver_vblank_wait(drm_device_t *dev, unsigned int *sequence)
  59 {
  60         unsigned int cur_vblank;
  61         int ret = 0;
  62
  63         /* Assume that the user has missed the current sequence number
  64          * by about a day rather than she wants to wait for years
  65          * using vertical blanks...
  66          */
  67         DRM_WAIT_ON( ret, dev->vbl_queue, 3*DRM_HZ,
  68                      ( ( ( cur_vblank = atomic_read(&dev->vbl_received ) )
  69                          - *sequence ) <= (1<<23) ) );
  70
  71         *sequence = cur_vblank;
  72
  73         return ret;
  74 }
  75
  76 void mga_driver_irq_preinstall( drm_device_t *dev ) {
  77         drm_mga_private_t *dev_priv =
  78            (drm_mga_private_t *)dev->dev_private;
  79
  80         /* Disable *all* interrupts */
  81         MGA_WRITE( MGA_IEN, 0 );
  82         /* Clear bits if they're already high */
  83         MGA_WRITE( MGA_ICLEAR, ~0 );
  84 }
  85
  86 void mga_driver_irq_postinstall( drm_device_t *dev ) {
  87         drm_mga_private_t *dev_priv =
  88            (drm_mga_private_t *)dev->dev_private;
  89
  90         /* Turn on VBL interrupt */
  91         MGA_WRITE( MGA_IEN, MGA_VLINEIEN );
  92 }
  93
  94 void mga_driver_irq_uninstall( drm_device_t *dev ) {
  95         drm_mga_private_t *dev_priv =
  96            (drm_mga_private_t *)dev->dev_private;
  97         if (!dev_priv)
  98                 return;
  99
 100         /* Disable *all* interrupts */
 101         MGA_WRITE( MGA_IEN, 0 );
 102 }