xref: /linux/drivers/gpu/drm/i915/gvt/mmio.c (revision e08a1d97d33e2ac05cd368b955f9fdc2823f15fd)
1 /*
2  * Copyright(c) 2011-2016 Intel Corporation. All rights reserved.
3  *
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:
10  *
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
13  * Software.
14  *
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 FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21  * SOFTWARE.
22  *
23  * Authors:
24  *    Ke Yu
25  *    Kevin Tian <kevin.tian@intel.com>
26  *    Dexuan Cui
27  *
28  * Contributors:
29  *    Tina Zhang <tina.zhang@intel.com>
30  *    Min He <min.he@intel.com>
31  *    Niu Bing <bing.niu@intel.com>
32  *    Zhi Wang <zhi.a.wang@intel.com>
33  *
34  */
35 
36 #include "i915_drv.h"
37 #include "gvt.h"
38 
39 /**
40  * intel_vgpu_gpa_to_mmio_offset - translate a GPA to MMIO offset
41  * @vgpu: a vGPU
42  *
43  * Returns:
44  * Zero on success, negative error code if failed
45  */
46 int intel_vgpu_gpa_to_mmio_offset(struct intel_vgpu *vgpu, u64 gpa)
47 {
48 	u64 gttmmio_gpa = *(u64 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_0) &
49 			  ~GENMASK(3, 0);
50 	return gpa - gttmmio_gpa;
51 }
52 
53 #define reg_is_mmio(gvt, reg)  \
54 	(reg >= 0 && reg < gvt->device_info.mmio_size)
55 
56 #define reg_is_gtt(gvt, reg)   \
57 	(reg >= gvt->device_info.gtt_start_offset \
58 	 && reg < gvt->device_info.gtt_start_offset + gvt_ggtt_sz(gvt))
59 
60 /**
61  * intel_vgpu_emulate_mmio_read - emulate MMIO read
62  * @vgpu: a vGPU
63  * @pa: guest physical address
64  * @p_data: data return buffer
65  * @bytes: access data length
66  *
67  * Returns:
68  * Zero on success, negative error code if failed
69  */
70 int intel_vgpu_emulate_mmio_read(void *__vgpu, uint64_t pa,
71 		void *p_data, unsigned int bytes)
72 {
73 	struct intel_vgpu *vgpu = __vgpu;
74 	struct intel_gvt *gvt = vgpu->gvt;
75 	struct intel_gvt_mmio_info *mmio;
76 	unsigned int offset = 0;
77 	int ret = -EINVAL;
78 
79 	mutex_lock(&gvt->lock);
80 
81 	if (atomic_read(&vgpu->gtt.n_write_protected_guest_page)) {
82 		struct intel_vgpu_guest_page *gp;
83 
84 		gp = intel_vgpu_find_guest_page(vgpu, pa >> PAGE_SHIFT);
85 		if (gp) {
86 			ret = intel_gvt_hypervisor_read_gpa(vgpu, pa,
87 					p_data, bytes);
88 			if (ret) {
89 				gvt_err("vgpu%d: guest page read error %d, "
90 					"gfn 0x%lx, pa 0x%llx, var 0x%x, len %d\n",
91 					vgpu->id, ret,
92 					gp->gfn, pa, *(u32 *)p_data, bytes);
93 			}
94 			mutex_unlock(&gvt->lock);
95 			return ret;
96 		}
97 	}
98 
99 	offset = intel_vgpu_gpa_to_mmio_offset(vgpu, pa);
100 
101 	if (WARN_ON(bytes > 8))
102 		goto err;
103 
104 	if (reg_is_gtt(gvt, offset)) {
105 		if (WARN_ON(!IS_ALIGNED(offset, 4) && !IS_ALIGNED(offset, 8)))
106 			goto err;
107 		if (WARN_ON(bytes != 4 && bytes != 8))
108 			goto err;
109 		if (WARN_ON(!reg_is_gtt(gvt, offset + bytes - 1)))
110 			goto err;
111 
112 		ret = intel_vgpu_emulate_gtt_mmio_read(vgpu, offset,
113 				p_data, bytes);
114 		if (ret)
115 			goto err;
116 		mutex_unlock(&gvt->lock);
117 		return ret;
118 	}
119 
120 	if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
121 		ret = intel_gvt_hypervisor_read_gpa(vgpu, pa, p_data, bytes);
122 		mutex_unlock(&gvt->lock);
123 		return ret;
124 	}
125 
126 	if (WARN_ON(!reg_is_mmio(gvt, offset + bytes - 1)))
127 		goto err;
128 
129 	mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
130 	if (!mmio && !vgpu->mmio.disable_warn_untrack) {
131 		gvt_err("vgpu%d: read untracked MMIO %x len %d val %x\n",
132 				vgpu->id, offset, bytes, *(u32 *)p_data);
133 
134 		if (offset == 0x206c) {
135 			gvt_err("------------------------------------------\n");
136 			gvt_err("vgpu%d: likely triggers a gfx reset\n",
137 			vgpu->id);
138 			gvt_err("------------------------------------------\n");
139 			vgpu->mmio.disable_warn_untrack = true;
140 		}
141 	}
142 
143 	if (!intel_gvt_mmio_is_unalign(gvt, offset)) {
144 		if (WARN_ON(!IS_ALIGNED(offset, bytes)))
145 			goto err;
146 	}
147 
148 	if (mmio) {
149 		if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
150 			if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
151 				goto err;
152 			if (WARN_ON(mmio->offset != offset))
153 				goto err;
154 		}
155 		ret = mmio->read(vgpu, offset, p_data, bytes);
156 	} else
157 		ret = intel_vgpu_default_mmio_read(vgpu, offset, p_data, bytes);
158 
159 	if (ret)
160 		goto err;
161 
162 	intel_gvt_mmio_set_accessed(gvt, offset);
163 	mutex_unlock(&gvt->lock);
164 	return 0;
165 err:
166 	gvt_err("vgpu%d: fail to emulate MMIO read %08x len %d\n",
167 			vgpu->id, offset, bytes);
168 	mutex_unlock(&gvt->lock);
169 	return ret;
170 }
171 
172 /**
173  * intel_vgpu_emulate_mmio_write - emulate MMIO write
174  * @vgpu: a vGPU
175  * @pa: guest physical address
176  * @p_data: write data buffer
177  * @bytes: access data length
178  *
179  * Returns:
180  * Zero on success, negative error code if failed
181  */
182 int intel_vgpu_emulate_mmio_write(void *__vgpu, uint64_t pa,
183 		void *p_data, unsigned int bytes)
184 {
185 	struct intel_vgpu *vgpu = __vgpu;
186 	struct intel_gvt *gvt = vgpu->gvt;
187 	struct intel_gvt_mmio_info *mmio;
188 	unsigned int offset = 0;
189 	u32 old_vreg = 0, old_sreg = 0;
190 	int ret = -EINVAL;
191 
192 	mutex_lock(&gvt->lock);
193 
194 	if (atomic_read(&vgpu->gtt.n_write_protected_guest_page)) {
195 		struct intel_vgpu_guest_page *gp;
196 
197 		gp = intel_vgpu_find_guest_page(vgpu, pa >> PAGE_SHIFT);
198 		if (gp) {
199 			ret = gp->handler(gp, pa, p_data, bytes);
200 			if (ret) {
201 				gvt_err("vgpu%d: guest page write error %d, "
202 					"gfn 0x%lx, pa 0x%llx, var 0x%x, len %d\n",
203 					vgpu->id, ret,
204 					gp->gfn, pa, *(u32 *)p_data, bytes);
205 			}
206 			mutex_unlock(&gvt->lock);
207 			return ret;
208 		}
209 	}
210 
211 	offset = intel_vgpu_gpa_to_mmio_offset(vgpu, pa);
212 
213 	if (WARN_ON(bytes > 8))
214 		goto err;
215 
216 	if (reg_is_gtt(gvt, offset)) {
217 		if (WARN_ON(!IS_ALIGNED(offset, 4) && !IS_ALIGNED(offset, 8)))
218 			goto err;
219 		if (WARN_ON(bytes != 4 && bytes != 8))
220 			goto err;
221 		if (WARN_ON(!reg_is_gtt(gvt, offset + bytes - 1)))
222 			goto err;
223 
224 		ret = intel_vgpu_emulate_gtt_mmio_write(vgpu, offset,
225 				p_data, bytes);
226 		if (ret)
227 			goto err;
228 		mutex_unlock(&gvt->lock);
229 		return ret;
230 	}
231 
232 	if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
233 		ret = intel_gvt_hypervisor_write_gpa(vgpu, pa, p_data, bytes);
234 		mutex_unlock(&gvt->lock);
235 		return ret;
236 	}
237 
238 	mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
239 	if (!mmio && !vgpu->mmio.disable_warn_untrack)
240 		gvt_err("vgpu%d: write untracked MMIO %x len %d val %x\n",
241 				vgpu->id, offset, bytes, *(u32 *)p_data);
242 
243 	if (!intel_gvt_mmio_is_unalign(gvt, offset)) {
244 		if (WARN_ON(!IS_ALIGNED(offset, bytes)))
245 			goto err;
246 	}
247 
248 	if (mmio) {
249 		u64 ro_mask = mmio->ro_mask;
250 
251 		if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
252 			if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
253 				goto err;
254 			if (WARN_ON(mmio->offset != offset))
255 				goto err;
256 		}
257 
258 		if (intel_gvt_mmio_has_mode_mask(gvt, mmio->offset)) {
259 			old_vreg = vgpu_vreg(vgpu, offset);
260 			old_sreg = vgpu_sreg(vgpu, offset);
261 		}
262 
263 		if (!ro_mask) {
264 			ret = mmio->write(vgpu, offset, p_data, bytes);
265 		} else {
266 			/* Protect RO bits like HW */
267 			u64 data = 0;
268 
269 			/* all register bits are RO. */
270 			if (ro_mask == ~(u64)0) {
271 				gvt_err("vgpu%d: try to write RO reg %x\n",
272 						vgpu->id, offset);
273 				ret = 0;
274 				goto out;
275 			}
276 			/* keep the RO bits in the virtual register */
277 			memcpy(&data, p_data, bytes);
278 			data &= ~mmio->ro_mask;
279 			data |= vgpu_vreg(vgpu, offset) & mmio->ro_mask;
280 			ret = mmio->write(vgpu, offset, &data, bytes);
281 		}
282 
283 		/* higher 16bits of mode ctl regs are mask bits for change */
284 		if (intel_gvt_mmio_has_mode_mask(gvt, mmio->offset)) {
285 			u32 mask = vgpu_vreg(vgpu, offset) >> 16;
286 
287 			vgpu_vreg(vgpu, offset) = (old_vreg & ~mask)
288 				| (vgpu_vreg(vgpu, offset) & mask);
289 			vgpu_sreg(vgpu, offset) = (old_sreg & ~mask)
290 				| (vgpu_sreg(vgpu, offset) & mask);
291 		}
292 	} else
293 		ret = intel_vgpu_default_mmio_write(vgpu, offset, p_data,
294 				bytes);
295 	if (ret)
296 		goto err;
297 out:
298 	intel_gvt_mmio_set_accessed(gvt, offset);
299 	mutex_unlock(&gvt->lock);
300 	return 0;
301 err:
302 	gvt_err("vgpu%d: fail to emulate MMIO write %08x len %d\n",
303 			vgpu->id, offset, bytes);
304 	mutex_unlock(&gvt->lock);
305 	return ret;
306 }
307