1 /**************************************************************************
2  *
3  * Copyright © 2009-2011 VMware, Inc., Palo Alto, CA., USA
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
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  **************************************************************************/
27 
28 #include "vmwgfx_drv.h"
29 #include <drm/drmP.h>
30 #include <drm/ttm/ttm_bo_driver.h>
31 
32 #define VMW_PPN_SIZE (sizeof(unsigned long))
33 /* A future safe maximum remap size. */
34 #define VMW_PPN_PER_REMAP ((31 * 1024) / VMW_PPN_SIZE)
35 
36 static int vmw_gmr2_bind(struct vmw_private *dev_priv,
37 			 struct page *pages[],
38 			 unsigned long num_pages,
39 			 int gmr_id)
40 {
41 	SVGAFifoCmdDefineGMR2 define_cmd;
42 	SVGAFifoCmdRemapGMR2 remap_cmd;
43 	uint32_t *cmd;
44 	uint32_t *cmd_orig;
45 	uint32_t define_size = sizeof(define_cmd) + sizeof(*cmd);
46 	uint32_t remap_num = num_pages / VMW_PPN_PER_REMAP + ((num_pages % VMW_PPN_PER_REMAP) > 0);
47 	uint32_t remap_size = VMW_PPN_SIZE * num_pages + (sizeof(remap_cmd) + sizeof(*cmd)) * remap_num;
48 	uint32_t remap_pos = 0;
49 	uint32_t cmd_size = define_size + remap_size;
50 	uint32_t i;
51 
52 	cmd_orig = cmd = vmw_fifo_reserve(dev_priv, cmd_size);
53 	if (unlikely(cmd == NULL))
54 		return -ENOMEM;
55 
56 	define_cmd.gmrId = gmr_id;
57 	define_cmd.numPages = num_pages;
58 
59 	*cmd++ = SVGA_CMD_DEFINE_GMR2;
60 	memcpy(cmd, &define_cmd, sizeof(define_cmd));
61 	cmd += sizeof(define_cmd) / sizeof(*cmd);
62 
63 	/*
64 	 * Need to split the command if there are too many
65 	 * pages that goes into the gmr.
66 	 */
67 
68 	remap_cmd.gmrId = gmr_id;
69 	remap_cmd.flags = (VMW_PPN_SIZE > sizeof(*cmd)) ?
70 		SVGA_REMAP_GMR2_PPN64 : SVGA_REMAP_GMR2_PPN32;
71 
72 	while (num_pages > 0) {
73 		unsigned long nr = min(num_pages, (unsigned long)VMW_PPN_PER_REMAP);
74 
75 		remap_cmd.offsetPages = remap_pos;
76 		remap_cmd.numPages = nr;
77 
78 		*cmd++ = SVGA_CMD_REMAP_GMR2;
79 		memcpy(cmd, &remap_cmd, sizeof(remap_cmd));
80 		cmd += sizeof(remap_cmd) / sizeof(*cmd);
81 
82 		for (i = 0; i < nr; ++i) {
83 			if (VMW_PPN_SIZE <= 4)
84 				*cmd = page_to_pfn(*pages++);
85 			else
86 				*((uint64_t *)cmd) = page_to_pfn(*pages++);
87 
88 			cmd += VMW_PPN_SIZE / sizeof(*cmd);
89 		}
90 
91 		num_pages -= nr;
92 		remap_pos += nr;
93 	}
94 
95 	BUG_ON(cmd != cmd_orig + cmd_size / sizeof(*cmd));
96 
97 	vmw_fifo_commit(dev_priv, cmd_size);
98 
99 	return 0;
100 }
101 
102 static void vmw_gmr2_unbind(struct vmw_private *dev_priv,
103 			    int gmr_id)
104 {
105 	SVGAFifoCmdDefineGMR2 define_cmd;
106 	uint32_t define_size = sizeof(define_cmd) + 4;
107 	uint32_t *cmd;
108 
109 	cmd = vmw_fifo_reserve(dev_priv, define_size);
110 	if (unlikely(cmd == NULL)) {
111 		DRM_ERROR("GMR2 unbind failed.\n");
112 		return;
113 	}
114 	define_cmd.gmrId = gmr_id;
115 	define_cmd.numPages = 0;
116 
117 	*cmd++ = SVGA_CMD_DEFINE_GMR2;
118 	memcpy(cmd, &define_cmd, sizeof(define_cmd));
119 
120 	vmw_fifo_commit(dev_priv, define_size);
121 }
122 
123 /**
124  * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
125  * the number of used descriptors.
126  */
127 
128 static int vmw_gmr_build_descriptors(struct list_head *desc_pages,
129 				     struct page *pages[],
130 				     unsigned long num_pages)
131 {
132 	struct page *page, *next;
133 	struct svga_guest_mem_descriptor *page_virtual = NULL;
134 	struct svga_guest_mem_descriptor *desc_virtual = NULL;
135 	unsigned int desc_per_page;
136 	unsigned long prev_pfn;
137 	unsigned long pfn;
138 	int ret;
139 
140 	desc_per_page = PAGE_SIZE /
141 	    sizeof(struct svga_guest_mem_descriptor) - 1;
142 
143 	while (likely(num_pages != 0)) {
144 		page = alloc_page(__GFP_HIGHMEM);
145 		if (unlikely(page == NULL)) {
146 			ret = -ENOMEM;
147 			goto out_err;
148 		}
149 
150 		list_add_tail(&page->lru, desc_pages);
151 
152 		/*
153 		 * Point previous page terminating descriptor to this
154 		 * page before unmapping it.
155 		 */
156 
157 		if (likely(page_virtual != NULL)) {
158 			desc_virtual->ppn = page_to_pfn(page);
159 			kunmap_atomic(page_virtual);
160 		}
161 
162 		page_virtual = kmap_atomic(page);
163 		desc_virtual = page_virtual - 1;
164 		prev_pfn = ~(0UL);
165 
166 		while (likely(num_pages != 0)) {
167 			pfn = page_to_pfn(*pages);
168 
169 			if (pfn != prev_pfn + 1) {
170 
171 				if (desc_virtual - page_virtual ==
172 				    desc_per_page - 1)
173 					break;
174 
175 				(++desc_virtual)->ppn = cpu_to_le32(pfn);
176 				desc_virtual->num_pages = cpu_to_le32(1);
177 			} else {
178 				uint32_t tmp =
179 				    le32_to_cpu(desc_virtual->num_pages);
180 				desc_virtual->num_pages = cpu_to_le32(tmp + 1);
181 			}
182 			prev_pfn = pfn;
183 			--num_pages;
184 			++pages;
185 		}
186 
187 		(++desc_virtual)->ppn = cpu_to_le32(0);
188 		desc_virtual->num_pages = cpu_to_le32(0);
189 	}
190 
191 	if (likely(page_virtual != NULL))
192 		kunmap_atomic(page_virtual);
193 
194 	return 0;
195 out_err:
196 	list_for_each_entry_safe(page, next, desc_pages, lru) {
197 		list_del_init(&page->lru);
198 		__free_page(page);
199 	}
200 	return ret;
201 }
202 
203 static inline void vmw_gmr_free_descriptors(struct list_head *desc_pages)
204 {
205 	struct page *page, *next;
206 
207 	list_for_each_entry_safe(page, next, desc_pages, lru) {
208 		list_del_init(&page->lru);
209 		__free_page(page);
210 	}
211 }
212 
213 static void vmw_gmr_fire_descriptors(struct vmw_private *dev_priv,
214 				     int gmr_id, struct list_head *desc_pages)
215 {
216 	struct page *page;
217 
218 	if (unlikely(list_empty(desc_pages)))
219 		return;
220 
221 	page = list_entry(desc_pages->next, struct page, lru);
222 
223 	mutex_lock(&dev_priv->hw_mutex);
224 
225 	vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
226 	wmb();
227 	vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, page_to_pfn(page));
228 	mb();
229 
230 	mutex_unlock(&dev_priv->hw_mutex);
231 
232 }
233 
234 /**
235  * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
236  * the number of used descriptors.
237  */
238 
239 static unsigned long vmw_gmr_count_descriptors(struct page *pages[],
240 					unsigned long num_pages)
241 {
242 	unsigned long prev_pfn = ~(0UL);
243 	unsigned long pfn;
244 	unsigned long descriptors = 0;
245 
246 	while (num_pages--) {
247 		pfn = page_to_pfn(*pages++);
248 		if (prev_pfn + 1 != pfn)
249 			++descriptors;
250 		prev_pfn = pfn;
251 	}
252 
253 	return descriptors;
254 }
255 
256 int vmw_gmr_bind(struct vmw_private *dev_priv,
257 		 struct page *pages[],
258 		 unsigned long num_pages,
259 		 int gmr_id)
260 {
261 	struct list_head desc_pages;
262 	int ret;
263 
264 	if (likely(dev_priv->capabilities & SVGA_CAP_GMR2))
265 		return vmw_gmr2_bind(dev_priv, pages, num_pages, gmr_id);
266 
267 	if (unlikely(!(dev_priv->capabilities & SVGA_CAP_GMR)))
268 		return -EINVAL;
269 
270 	if (vmw_gmr_count_descriptors(pages, num_pages) >
271 	    dev_priv->max_gmr_descriptors)
272 		return -EINVAL;
273 
274 	INIT_LIST_HEAD(&desc_pages);
275 
276 	ret = vmw_gmr_build_descriptors(&desc_pages, pages, num_pages);
277 	if (unlikely(ret != 0))
278 		return ret;
279 
280 	vmw_gmr_fire_descriptors(dev_priv, gmr_id, &desc_pages);
281 	vmw_gmr_free_descriptors(&desc_pages);
282 
283 	return 0;
284 }
285 
286 
287 void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id)
288 {
289 	if (likely(dev_priv->capabilities & SVGA_CAP_GMR2)) {
290 		vmw_gmr2_unbind(dev_priv, gmr_id);
291 		return;
292 	}
293 
294 	mutex_lock(&dev_priv->hw_mutex);
295 	vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
296 	wmb();
297 	vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, 0);
298 	mb();
299 	mutex_unlock(&dev_priv->hw_mutex);
300 }
301