1/* i830_dma.c -- DMA support for the I830 -*- linux-c -*-
2 *
3 * Copyright 2002 Tungsten Graphics, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the next
14 * paragraph) shall be included in all copies or substantial portions of the
15 * Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
23 * DEALINGS IN THE SOFTWARE.
24 *
25 * Authors: Keith Whitwell <keith@tungstengraphics.com>
26 *
27 */
28
29#include "drmP.h"
30#include "drm.h"
31#include "i830_drm.h"
32#include "i830_drv.h"
33#include <linux/interrupt.h>	/* For task queue support */
34#include <linux/delay.h>
35
36irqreturn_t i830_driver_irq_handler(DRM_IRQ_ARGS)
37{
38	drm_device_t *dev = (drm_device_t *) arg;
39	drm_i830_private_t *dev_priv = (drm_i830_private_t *) dev->dev_private;
40	u16 temp;
41
42	temp = I830_READ16(I830REG_INT_IDENTITY_R);
43	DRM_DEBUG("%x\n", temp);
44
45	if (!(temp & 2))
46		return IRQ_NONE;
47
48	I830_WRITE16(I830REG_INT_IDENTITY_R, temp);
49
50	atomic_inc(&dev_priv->irq_received);
51	wake_up_interruptible(&dev_priv->irq_queue);
52
53	return IRQ_HANDLED;
54}
55
56static int i830_emit_irq(drm_device_t * dev)
57{
58	drm_i830_private_t *dev_priv = dev->dev_private;
59	RING_LOCALS;
60
61	DRM_DEBUG("%s\n", __FUNCTION__);
62
63	atomic_inc(&dev_priv->irq_emitted);
64
65	BEGIN_LP_RING(2);
66	OUT_RING(0);
67	OUT_RING(GFX_OP_USER_INTERRUPT);
68	ADVANCE_LP_RING();
69
70	return atomic_read(&dev_priv->irq_emitted);
71}
72
73static int i830_wait_irq(drm_device_t * dev, int irq_nr)
74{
75	drm_i830_private_t *dev_priv = (drm_i830_private_t *) dev->dev_private;
76	DECLARE_WAITQUEUE(entry, current);
77	unsigned long end = jiffies + HZ * 3;
78	int ret = 0;
79
80	DRM_DEBUG("%s\n", __FUNCTION__);
81
82	if (atomic_read(&dev_priv->irq_received) >= irq_nr)
83		return 0;
84
85	dev_priv->sarea_priv->perf_boxes |= I830_BOX_WAIT;
86
87	add_wait_queue(&dev_priv->irq_queue, &entry);
88
89	for (;;) {
90		__set_current_state(TASK_INTERRUPTIBLE);
91		if (atomic_read(&dev_priv->irq_received) >= irq_nr)
92			break;
93		if ((signed)(end - jiffies) <= 0) {
94			DRM_ERROR("timeout iir %x imr %x ier %x hwstam %x\n",
95				  I830_READ16(I830REG_INT_IDENTITY_R),
96				  I830_READ16(I830REG_INT_MASK_R),
97				  I830_READ16(I830REG_INT_ENABLE_R),
98				  I830_READ16(I830REG_HWSTAM));
99
100			ret = -EBUSY;	/* Lockup?  Missed irq? */
101			break;
102		}
103		schedule_timeout(HZ * 3);
104		if (signal_pending(current)) {
105			ret = -EINTR;
106			break;
107		}
108	}
109
110	__set_current_state(TASK_RUNNING);
111	remove_wait_queue(&dev_priv->irq_queue, &entry);
112	return ret;
113}
114
115/* Needs the lock as it touches the ring.
116 */
117int i830_irq_emit(struct inode *inode, struct file *filp, unsigned int cmd,
118		  unsigned long arg)
119{
120	drm_file_t *priv = filp->private_data;
121	drm_device_t *dev = priv->head->dev;
122	drm_i830_private_t *dev_priv = dev->dev_private;
123	drm_i830_irq_emit_t emit;
124	int result;
125
126	LOCK_TEST_WITH_RETURN(dev, filp);
127
128	if (!dev_priv) {
129		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
130		return -EINVAL;
131	}
132
133	if (copy_from_user
134	    (&emit, (drm_i830_irq_emit_t __user *) arg, sizeof(emit)))
135		return -EFAULT;
136
137	result = i830_emit_irq(dev);
138
139	if (copy_to_user(emit.irq_seq, &result, sizeof(int))) {
140		DRM_ERROR("copy_to_user\n");
141		return -EFAULT;
142	}
143
144	return 0;
145}
146
147/* Doesn't need the hardware lock.
148 */
149int i830_irq_wait(struct inode *inode, struct file *filp, unsigned int cmd,
150		  unsigned long arg)
151{
152	drm_file_t *priv = filp->private_data;
153	drm_device_t *dev = priv->head->dev;
154	drm_i830_private_t *dev_priv = dev->dev_private;
155	drm_i830_irq_wait_t irqwait;
156
157	if (!dev_priv) {
158		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
159		return -EINVAL;
160	}
161
162	if (copy_from_user(&irqwait, (drm_i830_irq_wait_t __user *) arg,
163			   sizeof(irqwait)))
164		return -EFAULT;
165
166	return i830_wait_irq(dev, irqwait.irq_seq);
167}
168
169/* drm_dma.h hooks
170*/
171void i830_driver_irq_preinstall(drm_device_t * dev)
172{
173	drm_i830_private_t *dev_priv = (drm_i830_private_t *) dev->dev_private;
174
175	I830_WRITE16(I830REG_HWSTAM, 0xffff);
176	I830_WRITE16(I830REG_INT_MASK_R, 0x0);
177	I830_WRITE16(I830REG_INT_ENABLE_R, 0x0);
178	atomic_set(&dev_priv->irq_received, 0);
179	atomic_set(&dev_priv->irq_emitted, 0);
180	init_waitqueue_head(&dev_priv->irq_queue);
181}
182
183void i830_driver_irq_postinstall(drm_device_t * dev)
184{
185	drm_i830_private_t *dev_priv = (drm_i830_private_t *) dev->dev_private;
186
187	I830_WRITE16(I830REG_INT_ENABLE_R, 0x2);
188}
189
190void i830_driver_irq_uninstall(drm_device_t * dev)
191{
192	drm_i830_private_t *dev_priv = (drm_i830_private_t *) dev->dev_private;
193	if (!dev_priv)
194		return;
195
196	I830_WRITE16(I830REG_INT_MASK_R, 0xffff);
197	I830_WRITE16(I830REG_INT_ENABLE_R, 0x0);
198}
199