summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
blob: de0c5948521dcab39bef89190ca19750a738b983 (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 © 2009 VMware, Inc., Palo Alto, CA., USA
 * All Rights Reserved.
 *
 * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
 *
 **************************************************************************/

#include "vmwgfx_drv.h"
#include "drmP.h"
#include "ttm/ttm_bo_driver.h"

/**
 * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
 * the number of used descriptors.
 */

static int vmw_gmr_build_descriptors(struct list_head *desc_pages,
				     struct page *pages[],
				     unsigned long num_pages)
{
	struct page *page, *next;
	struct svga_guest_mem_descriptor *page_virtual = NULL;
	struct svga_guest_mem_descriptor *desc_virtual = NULL;
	unsigned int desc_per_page;
	unsigned long prev_pfn;
	unsigned long pfn;
	int ret;

	desc_per_page = PAGE_SIZE /
	    sizeof(struct svga_guest_mem_descriptor) - 1;

	while (likely(num_pages != 0)) {
		page = alloc_page(__GFP_HIGHMEM);
		if (unlikely(page == NULL)) {
			ret = -ENOMEM;
			goto out_err;
		}

		list_add_tail(&page->lru, desc_pages);

		/*
		 * Point previous page terminating descriptor to this
		 * page before unmapping it.
		 */

		if (likely(page_virtual != NULL)) {
			desc_virtual->ppn = page_to_pfn(page);
			kunmap_atomic(page_virtual, KM_USER0);
		}

		page_virtual = kmap_atomic(page, KM_USER0);
		desc_virtual = page_virtual - 1;
		prev_pfn = ~(0UL);

		while (likely(num_pages != 0)) {
			pfn = page_to_pfn(*pages);

			if (pfn != prev_pfn + 1) {

				if (desc_virtual - page_virtual ==
				    desc_per_page - 1)
					break;

				(++desc_virtual)->ppn = cpu_to_le32(pfn);
				desc_virtual->num_pages = cpu_to_le32(1);
			} else {
				uint32_t tmp =
				    le32_to_cpu(desc_virtual->num_pages);
				desc_virtual->num_pages = cpu_to_le32(tmp + 1);
			}
			prev_pfn = pfn;
			--num_pages;
			++pages;
		}

		(++desc_virtual)->ppn = cpu_to_le32(0);
		desc_virtual->num_pages = cpu_to_le32(0);
	}

	if (likely(page_virtual != NULL))
		kunmap_atomic(page_virtual, KM_USER0);

	return 0;
out_err:
	list_for_each_entry_safe(page, next, desc_pages, lru) {
		list_del_init(&page->lru);
		__free_page(page);
	}
	return ret;
}

static inline void vmw_gmr_free_descriptors(struct list_head *desc_pages)
{
	struct page *page, *next;

	list_for_each_entry_safe(page, next, desc_pages, lru) {
		list_del_init(&page->lru);
		__free_page(page);
	}
}

static void vmw_gmr_fire_descriptors(struct vmw_private *dev_priv,
				     int gmr_id, struct list_head *desc_pages)
{
	struct page *page;

	if (unlikely(list_empty(desc_pages)))
		return;

	page = list_entry(desc_pages->next, struct page, lru);

	mutex_lock(&dev_priv->hw_mutex);

	vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
	wmb();
	vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, page_to_pfn(page));
	mb();

	mutex_unlock(&dev_priv->hw_mutex);

}

/**
 * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
 * the number of used descriptors.
 */

static unsigned long vmw_gmr_count_descriptors(struct page *pages[],
					unsigned long num_pages)
{
	unsigned long prev_pfn = ~(0UL);
	unsigned long pfn;
	unsigned long descriptors = 0;

	while (num_pages--) {
		pfn = page_to_pfn(*pages++);
		if (prev_pfn + 1 != pfn)
			++descriptors;
		prev_pfn = pfn;
	}

	return descriptors;
}

int vmw_gmr_bind(struct vmw_private *dev_priv,
		 struct page *pages[],
		 unsigned long num_pages,
		 int gmr_id)
{
	struct list_head desc_pages;
	int ret;

	if (unlikely(!(dev_priv->capabilities & SVGA_CAP_GMR)))
		return -EINVAL;

	if (vmw_gmr_count_descriptors(pages, num_pages) >
	    dev_priv->max_gmr_descriptors)
		return -EINVAL;

	INIT_LIST_HEAD(&desc_pages);

	ret = vmw_gmr_build_descriptors(&desc_pages, pages, num_pages);
	if (unlikely(ret != 0))
		return ret;

	vmw_gmr_fire_descriptors(dev_priv, gmr_id, &desc_pages);
	vmw_gmr_free_descriptors(&desc_pages);

	return 0;
}


void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id)
{
	mutex_lock(&dev_priv->hw_mutex);
	vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
	wmb();
	vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, 0);
	mb();
	mutex_unlock(&dev_priv->hw_mutex);
}
OpenPOWER on IntegriCloud