sys/dev/drm/mga_irq.c

   1 /* mga_irq.c -- IRQ handling for radeon -*- linux-c -*-
   2  */
   3 /*-
   4  * Copyright (C) The Weather Channel, Inc.  2002.  All Rights Reserved.
   5  *
   6  * The Weather Channel (TM) funded Tungsten Graphics to develop the
   7  * initial release of the Radeon 8500 driver under the XFree86 license.
   8  * This notice must be preserved.
   9  *
  10  * Permission is hereby granted, free of charge, to any person obtaining a
  11  * copy of this software and associated documentation files (the "Software"),
  12  * to deal in the Software without restriction, including without limitation
  13  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  14  * and/or sell copies of the Software, and to permit persons to whom the
  15  * Software is furnished to do so, subject to the following conditions:
  16  *
  17  * The above copyright notice and this permission notice (including the next
  18  * paragraph) shall be included in all copies or substantial portions of the
  19  * Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  24  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  25  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  26  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  27  * DEALINGS IN THE SOFTWARE.
  28  *
  29  * Authors:
  30  *    Keith Whitwell <keith@tungstengraphics.com>
  31  *    Eric Anholt <anholt@FreeBSD.org>
  32  */
  33
  34 #include "dev/drm/drmP.h"
  35 #include "dev/drm/drm.h"
  36 #include "dev/drm/mga_drm.h"
  37 #include "dev/drm/mga_drv.h"
  38
  39 u32 mga_get_vblank_counter(struct drm_device *dev, int crtc)
  40 {
  41         const drm_mga_private_t *const dev_priv =
  42                 (drm_mga_private_t *) dev->dev_private;
  43
  44         if (crtc != 0) {
  45                 return 0;
  46         }
  47
  48
  49         return atomic_read(&dev_priv->vbl_received);
  50 }
  51
  52
  53 irqreturn_t mga_driver_irq_handler(DRM_IRQ_ARGS)
  54 {
  55         struct drm_device *dev = (struct drm_device *) arg;
  56         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
  57         int status;
  58         int handled = 0;
  59
  60         status = MGA_READ(MGA_STATUS);
  61
  62         /* VBLANK interrupt */
  63         if (status & MGA_VLINEPEN) {
  64                 MGA_WRITE(MGA_ICLEAR, MGA_VLINEICLR);
  65                 atomic_inc(&dev_priv->vbl_received);
  66                 drm_handle_vblank(dev, 0);
  67                 handled = 1;
  68         }
  69
  70         /* SOFTRAP interrupt */
  71         if (status & MGA_SOFTRAPEN) {
  72                 const u32 prim_start = MGA_READ(MGA_PRIMADDRESS);
  73                 const u32 prim_end = MGA_READ(MGA_PRIMEND);
  74
  75
  76                 MGA_WRITE(MGA_ICLEAR, MGA_SOFTRAPICLR);
  77
  78                 /* In addition to clearing the interrupt-pending bit, we
  79                  * have to write to MGA_PRIMEND to re-start the DMA operation.
  80                  */
  81                 if ((prim_start & ~0x03) != (prim_end & ~0x03)) {
  82                         MGA_WRITE(MGA_PRIMEND, prim_end);
  83                 }
  84
  85                 atomic_inc(&dev_priv->last_fence_retired);
  86                 DRM_WAKEUP(&dev_priv->fence_queue);
  87                 handled = 1;
  88         }
  89
  90         if (handled)
  91                 return IRQ_HANDLED;
  92         return IRQ_NONE;
  93 }
  94
  95 int mga_enable_vblank(struct drm_device *dev, int crtc)
  96 {
  97         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
  98
  99         if (crtc != 0) {
 100                 DRM_ERROR("tried to enable vblank on non-existent crtc %d\n",
 101                           crtc);
 102                 return 0;
 103         }
 104
 105         MGA_WRITE(MGA_IEN, MGA_VLINEIEN | MGA_SOFTRAPEN);
 106         return 0;
 107 }
 108
 109
 110 void mga_disable_vblank(struct drm_device *dev, int crtc)
 111 {
 112         if (crtc != 0) {
 113                 DRM_ERROR("tried to disable vblank on non-existent crtc %d\n",
 114                           crtc);
 115         }
 116
 117         /* Do *NOT* disable the vertical refresh interrupt.  MGA doesn't have
 118          * a nice hardware counter that tracks the number of refreshes when
 119          * the interrupt is disabled, and the kernel doesn't know the refresh
 120          * rate to calculate an estimate.
 121          */
 122         /* MGA_WRITE(MGA_IEN, MGA_VLINEIEN | MGA_SOFTRAPEN); */
 123 }
 124
 125 int mga_driver_fence_wait(struct drm_device * dev, unsigned int *sequence)
 126 {
 127         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 128         unsigned int cur_fence;
 129         int ret = 0;
 130
 131         /* Assume that the user has missed the current sequence number
 132          * by about a day rather than she wants to wait for years
 133          * using fences.
 134          */
 135         DRM_WAIT_ON(ret, dev_priv->fence_queue, 3 * DRM_HZ,
 136                     (((cur_fence = atomic_read(&dev_priv->last_fence_retired))
 137                       - *sequence) <= (1 << 23)));
 138
 139         if (ret == -ERESTART)
 140                 DRM_DEBUG("restarting syscall\n");
 141
 142         *sequence = cur_fence;
 143
 144         return ret;
 145 }
 146
 147 void mga_driver_irq_preinstall(struct drm_device * dev)
 148 {
 149         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 150
 151         /* Disable *all* interrupts */
 152         MGA_WRITE(MGA_IEN, 0);
 153         /* Clear bits if they're already high */
 154         MGA_WRITE(MGA_ICLEAR, ~0);
 155 }
 156
 157 int mga_driver_irq_postinstall(struct drm_device * dev)
 158 {
 159         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 160
 161         DRM_INIT_WAITQUEUE(&dev_priv->fence_queue);
 162
 163         /* Turn on soft trap interrupt.  Vertical blank interrupts are enabled
 164          * in mga_enable_vblank.
 165          */
 166         MGA_WRITE(MGA_IEN, MGA_SOFTRAPEN);
 167         return 0;
 168 }
 169
 170 void mga_driver_irq_uninstall(struct drm_device * dev)
 171 {
 172         drm_mga_private_t *dev_priv = (drm_mga_private_t *) dev->dev_private;
 173         if (!dev_priv)
 174                 return;
 175
 176         /* Disable *all* interrupts */
 177         MGA_WRITE(MGA_IEN, 0);
 178
 179         dev->irq_enabled = 0;
 180 }