2 * Copyright © 2008-2012 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
24 * Eric Anholt <eric@anholt.net>
25 * Chris Wilson <chris@chris-wilson.co.uk>
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
32 #include <dev/drm2/drmP.h>
33 #include <dev/drm2/i915/i915_drm.h>
34 #include <dev/drm2/i915/i915_drv.h>
37 * The BIOS typically reserves some of the system's memory for the exclusive
38 * use of the integrated graphics. This memory is no longer available for
39 * use by the OS and so the user finds that his system has less memory
40 * available than he put in. We refer to this memory as stolen.
42 * The BIOS will allocate its framebuffer from the stolen memory. Our
43 * goal is try to reuse that object for our own fbcon which must always
44 * be available for panics. Anything else we can reuse the stolen memory
48 static unsigned long i915_stolen_to_physical(struct drm_device *dev)
52 /* On the machines I have tested the Graphics Base of Stolen Memory
53 * is unreliable, so on those compute the base by subtracting the
54 * stolen memory from the Top of Low Usable DRAM which is where the
55 * BIOS places the graphics stolen memory.
57 * On gen2, the layout is slightly different with the Graphics Segment
58 * immediately following Top of Memory (or Top of Usable DRAM). Note
59 * it appears that TOUD is only reported by 865g, so we just use the
60 * top of memory as determined by the e820 probe.
62 * XXX gen2 requires an unavailable symbol and 945gm fails with
66 if (INTEL_INFO(dev)->gen >= 6) {
67 /* Read Base Data of Stolen Memory Register (BDSM) directly.
68 * Note that there is also a MCHBAR miror at 0x1080c0 or
69 * we could use device 2:0x5c instead.
71 pci_read_config_dword(dev->dev, 0xB0, &base);
72 base &= ~4095; /* lower bits used for locking register */
73 } else if (INTEL_INFO(dev)->gen > 3 || IS_G33(dev)) {
74 /* Read Graphics Base of Stolen Memory directly */
75 pci_read_config_dword(dev->dev, 0xA4, &base);
77 } else if (IS_GEN3(dev)) {
79 /* Stolen is immediately below Top of Low Usable DRAM */
80 pci_read_config_byte(pdev, 0x9c, &val);
81 base = val >> 3 << 27;
82 base -= dev_priv->mm.gtt->stolen_size;
84 /* Stolen is immediately above Top of Memory */
85 base = max_low_pfn_mapped << PAGE_SHIFT;
92 static void i915_warn_stolen(struct drm_device *dev)
94 DRM_INFO("not enough stolen space for compressed buffer, disabling\n");
95 DRM_INFO("hint: you may be able to increase stolen memory size in the BIOS to avoid this\n");
98 static void i915_setup_compression(struct drm_device *dev, int size)
100 struct drm_i915_private *dev_priv = dev->dev_private;
101 struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
102 unsigned long cfb_base;
103 unsigned long ll_base = 0;
105 /* Just in case the BIOS is doing something questionable. */
106 intel_disable_fbc(dev);
108 compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen, size, 4096, 0);
110 compressed_fb = drm_mm_get_block(compressed_fb, size, 4096);
114 cfb_base = dev_priv->mm.stolen_base + compressed_fb->start;
118 if (!(IS_GM45(dev) || HAS_PCH_SPLIT(dev))) {
119 compressed_llb = drm_mm_search_free(&dev_priv->mm.stolen,
122 compressed_llb = drm_mm_get_block(compressed_llb,
127 ll_base = dev_priv->mm.stolen_base + compressed_llb->start;
132 dev_priv->cfb_size = size;
134 dev_priv->compressed_fb = compressed_fb;
135 if (HAS_PCH_SPLIT(dev))
136 I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
137 else if (IS_GM45(dev)) {
138 I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
140 I915_WRITE(FBC_CFB_BASE, cfb_base);
141 I915_WRITE(FBC_LL_BASE, ll_base);
142 dev_priv->compressed_llb = compressed_llb;
145 DRM_DEBUG_KMS("FBC base 0x%08lx, ll base 0x%08lx, size %dM\n",
146 (long)cfb_base, (long)ll_base, size >> 20);
150 drm_mm_put_block(compressed_llb);
152 drm_mm_put_block(compressed_fb);
154 dev_priv->no_fbc_reason = FBC_STOLEN_TOO_SMALL;
155 i915_warn_stolen(dev);
158 static void i915_cleanup_compression(struct drm_device *dev)
160 struct drm_i915_private *dev_priv = dev->dev_private;
162 drm_mm_put_block(dev_priv->compressed_fb);
163 if (dev_priv->compressed_llb)
164 drm_mm_put_block(dev_priv->compressed_llb);
167 void i915_gem_cleanup_stolen(struct drm_device *dev)
169 if (I915_HAS_FBC(dev) && i915_powersave)
170 i915_cleanup_compression(dev);
173 int i915_gem_init_stolen(struct drm_device *dev)
175 struct drm_i915_private *dev_priv = dev->dev_private;
176 unsigned long prealloc_size = dev_priv->mm.gtt->stolen_size;
178 dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
179 if (dev_priv->mm.stolen_base == 0)
182 DRM_DEBUG_KMS("found %d bytes of stolen memory at %08lx\n",
183 dev_priv->mm.gtt->stolen_size, dev_priv->mm.stolen_base);
185 /* Basic memrange allocator for stolen space */
186 drm_mm_init(&dev_priv->mm.stolen, 0, prealloc_size);
188 /* Try to set up FBC with a reasonable compressed buffer size */
189 if (I915_HAS_FBC(dev) && i915_powersave) {
192 /* Leave 1M for line length buffer & misc. */
194 /* Try to get a 32M buffer... */
195 if (prealloc_size > (36*1024*1024))
196 cfb_size = 32*1024*1024;
197 else /* fall back to 7/8 of the stolen space */
198 cfb_size = prealloc_size * 7 / 8;
199 i915_setup_compression(dev, cfb_size);