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         struct drm_device *dev = (struct drm_device *) arg;
  41         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
  42         int status;
  43         int handled = 0;
  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                 handled = 1;
  54         }
  55
  56         /* SOFTRAP interrupt */
  57         if (status & MGA_SOFTRAPEN) {
  58                 const u32 prim_start = MGA_READ(MGA_PRIMADDRESS);
  59                 const u32 prim_end = MGA_READ(MGA_PRIMEND);
  60
  61                 MGA_WRITE(MGA_ICLEAR, MGA_SOFTRAPICLR);
  62
  63                 /* In addition to clearing the interrupt-pending bit, we
  64                  * have to write to MGA_PRIMEND to re-start the DMA operation.
  65                  */
  66                 if ((prim_start & ~0x03) != (prim_end & ~0x03)) {
  67                         MGA_WRITE(MGA_PRIMEND, prim_end);
  68                 }
  69
  70                 atomic_inc(&dev_priv->last_fence_retired);
  71                 DRM_WAKEUP(&dev_priv->fence_queue);
  72                 handled = 1;
  73         }
  74
  75         if (handled) {
  76                 return IRQ_HANDLED;
  77         }
  78         return IRQ_NONE;
  79 }
  80
  81 int mga_driver_vblank_wait(struct drm_device * dev, unsigned int *sequence)
  82 {
  83         unsigned int cur_vblank;
  84         int ret = 0;
  85
  86         /* Assume that the user has missed the current sequence number
  87          * by about a day rather than she wants to wait for years
  88          * using vertical blanks...
  89          */
  90         DRM_WAIT_ON(ret, dev->vbl_queue, 3 * DRM_HZ,
  91                     (((cur_vblank = atomic_read(&dev->vbl_received))
  92                       - *sequence) <= (1 << 23)));
  93
  94         *sequence = cur_vblank;
  95
  96         return ret;
  97 }
  98
  99 int mga_driver_fence_wait(struct drm_device * dev, unsigned int *sequence)
 100 {
 101         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 102         unsigned int cur_fence;
 103         int ret = 0;
 104
 105         /* Assume that the user has missed the current sequence number
 106          * by about a day rather than she wants to wait for years
 107          * using fences.
 108          */
 109         DRM_WAIT_ON(ret, dev_priv->fence_queue, 3 * DRM_HZ,
 110                     (((cur_fence = atomic_read(&dev_priv->last_fence_retired))
 111                       - *sequence) <= (1 << 23)));
 112
 113         *sequence = cur_fence;
 114
 115         return ret;
 116 }
 117
 118 void mga_driver_irq_preinstall(struct drm_device * dev)
 119 {
 120         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 121
 122         /* Disable *all* interrupts */
 123         MGA_WRITE(MGA_IEN, 0);
 124         /* Clear bits if they're already high */
 125         MGA_WRITE(MGA_ICLEAR, ~0);
 126 }
 127
 128 void mga_driver_irq_postinstall(struct drm_device * dev)
 129 {
 130         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 131
 132         DRM_INIT_WAITQUEUE(&dev_priv->fence_queue);
 133
 134         /* Turn on vertical blank interrupt and soft trap interrupt. */
 135         MGA_WRITE(MGA_IEN, MGA_VLINEIEN | MGA_SOFTRAPEN);
 136 }
 137
 138 void mga_driver_irq_uninstall(struct drm_device * dev)
 139 {
 140         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 141         if (!dev_priv)
 142                 return;
 143
 144         /* Disable *all* interrupts */
 145         MGA_WRITE(MGA_IEN, 0);
 146
 147         dev->irq_enabled = 0;
 148 }