aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/i915/i915_gem_stolen.c
blob: de023c1cb7c1dfe0d2168bdacf609d409bd4c304 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
/*
 * Copyright © 2008-2012 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *    Chris Wilson <chris@chris-wilson.co.uk>
 *
 */

#include "drmP.h"
#include "i915_drm.h"
#include "i915_drv.h"

/*
 * The BIOS typically reserves some of the system's memory for the exclusive
 * use of the integrated graphics. This memory is no longer available for
 * use by the OS and so the user finds that his system has less memory
 * available than he put in. We refer to this memory as stolen.
 *
 * The BIOS will allocate its framebuffer from the stolen memory. Our
 * goal is try to reuse that object for our own fbcon which must always
 * be available for panics. Anything else we can reuse the stolen memory
 * for is a boon.
 */

#define PTE_ADDRESS_MASK		0xfffff000
#define PTE_ADDRESS_MASK_HIGH		0x000000f0 /* i915+ */
#define PTE_MAPPING_TYPE_UNCACHED	(0 << 1)
#define PTE_MAPPING_TYPE_DCACHE		(1 << 1) /* i830 only */
#define PTE_MAPPING_TYPE_CACHED		(3 << 1)
#define PTE_MAPPING_TYPE_MASK		(3 << 1)
#define PTE_VALID			(1 << 0)

/**
 * i915_stolen_to_phys - take an offset into stolen memory and turn it into
 *                       a physical one
 * @dev: drm device
 * @offset: address to translate
 *
 * Some chip functions require allocations from stolen space and need the
 * physical address of the memory in question.
 */
static unsigned long i915_stolen_to_phys(struct drm_device *dev, u32 offset)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct pci_dev *pdev = dev_priv->bridge_dev;
	u32 base;

#if 0
	/* On the machines I have tested the Graphics Base of Stolen Memory
	 * is unreliable, so compute the base by subtracting the stolen memory
	 * from the Top of Low Usable DRAM which is where the BIOS places
	 * the graphics stolen memory.
	 */
	if (INTEL_INFO(dev)->gen > 3 || IS_G33(dev)) {
		/* top 32bits are reserved = 0 */
		pci_read_config_dword(pdev, 0xA4, &base);
	} else {
		/* XXX presume 8xx is the same as i915 */
		pci_bus_read_config_dword(pdev->bus, 2, 0x5C, &base);
	}
#else
	if (INTEL_INFO(dev)->gen > 3 || IS_G33(dev)) {
		u16 val;
		pci_read_config_word(pdev, 0xb0, &val);
		base = val >> 4 << 20;
	} else {
		u8 val;
		pci_read_config_byte(pdev, 0x9c, &val);
		base = val >> 3 << 27;
	}
	base -= dev_priv->mm.gtt->stolen_size;
#endif

	return base + offset;
}

static void i915_warn_stolen(struct drm_device *dev)
{
	DRM_INFO("not enough stolen space for compressed buffer, disabling\n");
	DRM_INFO("hint: you may be able to increase stolen memory size in the BIOS to avoid this\n");
}

static void i915_setup_compression(struct drm_device *dev, int size)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
	unsigned long cfb_base;
	unsigned long ll_base = 0;

	/* Just in case the BIOS is doing something questionable. */
	intel_disable_fbc(dev);

	compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen, size, 4096, 0);
	if (compressed_fb)
		compressed_fb = drm_mm_get_block(compressed_fb, size, 4096);
	if (!compressed_fb)
		goto err;

	cfb_base = i915_stolen_to_phys(dev, compressed_fb->start);
	if (!cfb_base)
		goto err_fb;

	if (!(IS_GM45(dev) || HAS_PCH_SPLIT(dev))) {
		compressed_llb = drm_mm_search_free(&dev_priv->mm.stolen,
						    4096, 4096, 0);
		if (compressed_llb)
			compressed_llb = drm_mm_get_block(compressed_llb,
							  4096, 4096);
		if (!compressed_llb)
			goto err_fb;

		ll_base = i915_stolen_to_phys(dev, compressed_llb->start);
		if (!ll_base)
			goto err_llb;
	}

	dev_priv->cfb_size = size;

	dev_priv->compressed_fb = compressed_fb;
	if (HAS_PCH_SPLIT(dev))
		I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
	else if (IS_GM45(dev)) {
		I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
	} else {
		I915_WRITE(FBC_CFB_BASE, cfb_base);
		I915_WRITE(FBC_LL_BASE, ll_base);
		dev_priv->compressed_llb = compressed_llb;
	}

	DRM_DEBUG_KMS("FBC base 0x%08lx, ll base 0x%08lx, size %dM\n",
		      cfb_base, ll_base, size >> 20);
	return;

err_llb:
	drm_mm_put_block(compressed_llb);
err_fb:
	drm_mm_put_block(compressed_fb);
err:
	dev_priv->no_fbc_reason = FBC_STOLEN_TOO_SMALL;
	i915_warn_stolen(dev);
}

static void i915_cleanup_compression(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	drm_mm_put_block(dev_priv->compressed_fb);
	if (dev_priv->compressed_llb)
		drm_mm_put_block(dev_priv->compressed_llb);
}

void i915_gem_cleanup_stolen(struct drm_device *dev)
{
	if (I915_HAS_FBC(dev) && i915_powersave)
		i915_cleanup_compression(dev);
}

int i915_gem_init_stolen(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	unsigned long prealloc_size = dev_priv->mm.gtt->stolen_size;

	/* Basic memrange allocator for stolen space */
	drm_mm_init(&dev_priv->mm.stolen, 0, prealloc_size);

	/* Try to set up FBC with a reasonable compressed buffer size */
	if (I915_HAS_FBC(dev) && i915_powersave) {
		int cfb_size;

		/* Leave 1M for line length buffer & misc. */

		/* Try to get a 32M buffer... */
		if (prealloc_size > (36*1024*1024))
			cfb_size = 32*1024*1024;
		else /* fall back to 7/8 of the stolen space */
			cfb_size = prealloc_size * 7 / 8;
		i915_setup_compression(dev, cfb_size);
	}

	return 0;
}