xref: /openbmc/linux/drivers/gpu/drm/i915/gvt/mmio.c (revision 8730046c)
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(struct intel_vgpu *vgpu, uint64_t pa,
71 		void *p_data, unsigned int bytes)
72 {
73 	struct intel_gvt *gvt = vgpu->gvt;
74 	struct intel_gvt_mmio_info *mmio;
75 	unsigned int offset = 0;
76 	int ret = -EINVAL;
77 
78 	mutex_lock(&gvt->lock);
79 
80 	if (atomic_read(&vgpu->gtt.n_write_protected_guest_page)) {
81 		struct intel_vgpu_guest_page *gp;
82 
83 		gp = intel_vgpu_find_guest_page(vgpu, pa >> PAGE_SHIFT);
84 		if (gp) {
85 			ret = intel_gvt_hypervisor_read_gpa(vgpu, pa,
86 					p_data, bytes);
87 			if (ret) {
88 				gvt_err("vgpu%d: guest page read error %d, "
89 					"gfn 0x%lx, pa 0x%llx, var 0x%x, len %d\n",
90 					vgpu->id, ret,
91 					gp->gfn, pa, *(u32 *)p_data, bytes);
92 			}
93 			mutex_unlock(&gvt->lock);
94 			return ret;
95 		}
96 	}
97 
98 	offset = intel_vgpu_gpa_to_mmio_offset(vgpu, pa);
99 
100 	if (WARN_ON(bytes > 8))
101 		goto err;
102 
103 	if (reg_is_gtt(gvt, offset)) {
104 		if (WARN_ON(!IS_ALIGNED(offset, 4) && !IS_ALIGNED(offset, 8)))
105 			goto err;
106 		if (WARN_ON(bytes != 4 && bytes != 8))
107 			goto err;
108 		if (WARN_ON(!reg_is_gtt(gvt, offset + bytes - 1)))
109 			goto err;
110 
111 		ret = intel_vgpu_emulate_gtt_mmio_read(vgpu, offset,
112 				p_data, bytes);
113 		if (ret)
114 			goto err;
115 		mutex_unlock(&gvt->lock);
116 		return ret;
117 	}
118 
119 	if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
120 		ret = intel_gvt_hypervisor_read_gpa(vgpu, pa, p_data, bytes);
121 		mutex_unlock(&gvt->lock);
122 		return ret;
123 	}
124 
125 	if (WARN_ON(!reg_is_mmio(gvt, offset + bytes - 1)))
126 		goto err;
127 
128 	mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
129 	if (!mmio && !vgpu->mmio.disable_warn_untrack) {
130 		gvt_err("vgpu%d: read untracked MMIO %x len %d val %x\n",
131 				vgpu->id, offset, bytes, *(u32 *)p_data);
132 
133 		if (offset == 0x206c) {
134 			gvt_err("------------------------------------------\n");
135 			gvt_err("vgpu%d: likely triggers a gfx reset\n",
136 			vgpu->id);
137 			gvt_err("------------------------------------------\n");
138 			vgpu->mmio.disable_warn_untrack = true;
139 		}
140 	}
141 
142 	if (!intel_gvt_mmio_is_unalign(gvt, offset)) {
143 		if (WARN_ON(!IS_ALIGNED(offset, bytes)))
144 			goto err;
145 	}
146 
147 	if (mmio) {
148 		if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
149 			if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
150 				goto err;
151 			if (WARN_ON(mmio->offset != offset))
152 				goto err;
153 		}
154 		ret = mmio->read(vgpu, offset, p_data, bytes);
155 	} else
156 		ret = intel_vgpu_default_mmio_read(vgpu, offset, p_data, bytes);
157 
158 	if (ret)
159 		goto err;
160 
161 	intel_gvt_mmio_set_accessed(gvt, offset);
162 	mutex_unlock(&gvt->lock);
163 	return 0;
164 err:
165 	gvt_err("vgpu%d: fail to emulate MMIO read %08x len %d\n",
166 			vgpu->id, offset, bytes);
167 	mutex_unlock(&gvt->lock);
168 	return ret;
169 }
170 
171 /**
172  * intel_vgpu_emulate_mmio_write - emulate MMIO write
173  * @vgpu: a vGPU
174  * @pa: guest physical address
175  * @p_data: write data buffer
176  * @bytes: access data length
177  *
178  * Returns:
179  * Zero on success, negative error code if failed
180  */
181 int intel_vgpu_emulate_mmio_write(struct intel_vgpu *vgpu, uint64_t pa,
182 		void *p_data, unsigned int bytes)
183 {
184 	struct intel_gvt *gvt = vgpu->gvt;
185 	struct intel_gvt_mmio_info *mmio;
186 	unsigned int offset = 0;
187 	u32 old_vreg = 0, old_sreg = 0;
188 	int ret = -EINVAL;
189 
190 	mutex_lock(&gvt->lock);
191 
192 	if (atomic_read(&vgpu->gtt.n_write_protected_guest_page)) {
193 		struct intel_vgpu_guest_page *gp;
194 
195 		gp = intel_vgpu_find_guest_page(vgpu, pa >> PAGE_SHIFT);
196 		if (gp) {
197 			ret = gp->handler(gp, pa, p_data, bytes);
198 			if (ret) {
199 				gvt_err("vgpu%d: guest page write error %d, "
200 					"gfn 0x%lx, pa 0x%llx, var 0x%x, len %d\n",
201 					vgpu->id, ret,
202 					gp->gfn, pa, *(u32 *)p_data, bytes);
203 			}
204 			mutex_unlock(&gvt->lock);
205 			return ret;
206 		}
207 	}
208 
209 	offset = intel_vgpu_gpa_to_mmio_offset(vgpu, pa);
210 
211 	if (WARN_ON(bytes > 8))
212 		goto err;
213 
214 	if (reg_is_gtt(gvt, offset)) {
215 		if (WARN_ON(!IS_ALIGNED(offset, 4) && !IS_ALIGNED(offset, 8)))
216 			goto err;
217 		if (WARN_ON(bytes != 4 && bytes != 8))
218 			goto err;
219 		if (WARN_ON(!reg_is_gtt(gvt, offset + bytes - 1)))
220 			goto err;
221 
222 		ret = intel_vgpu_emulate_gtt_mmio_write(vgpu, offset,
223 				p_data, bytes);
224 		if (ret)
225 			goto err;
226 		mutex_unlock(&gvt->lock);
227 		return ret;
228 	}
229 
230 	if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
231 		ret = intel_gvt_hypervisor_write_gpa(vgpu, pa, p_data, bytes);
232 		mutex_unlock(&gvt->lock);
233 		return ret;
234 	}
235 
236 	mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
237 	if (!mmio && !vgpu->mmio.disable_warn_untrack)
238 		gvt_err("vgpu%d: write untracked MMIO %x len %d val %x\n",
239 				vgpu->id, offset, bytes, *(u32 *)p_data);
240 
241 	if (!intel_gvt_mmio_is_unalign(gvt, offset)) {
242 		if (WARN_ON(!IS_ALIGNED(offset, bytes)))
243 			goto err;
244 	}
245 
246 	if (mmio) {
247 		u64 ro_mask = mmio->ro_mask;
248 
249 		if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
250 			if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
251 				goto err;
252 			if (WARN_ON(mmio->offset != offset))
253 				goto err;
254 		}
255 
256 		if (intel_gvt_mmio_has_mode_mask(gvt, mmio->offset)) {
257 			old_vreg = vgpu_vreg(vgpu, offset);
258 			old_sreg = vgpu_sreg(vgpu, offset);
259 		}
260 
261 		if (!ro_mask) {
262 			ret = mmio->write(vgpu, offset, p_data, bytes);
263 		} else {
264 			/* Protect RO bits like HW */
265 			u64 data = 0;
266 
267 			/* all register bits are RO. */
268 			if (ro_mask == ~(u64)0) {
269 				gvt_err("vgpu%d: try to write RO reg %x\n",
270 						vgpu->id, offset);
271 				ret = 0;
272 				goto out;
273 			}
274 			/* keep the RO bits in the virtual register */
275 			memcpy(&data, p_data, bytes);
276 			data &= ~mmio->ro_mask;
277 			data |= vgpu_vreg(vgpu, offset) & mmio->ro_mask;
278 			ret = mmio->write(vgpu, offset, &data, bytes);
279 		}
280 
281 		/* higher 16bits of mode ctl regs are mask bits for change */
282 		if (intel_gvt_mmio_has_mode_mask(gvt, mmio->offset)) {
283 			u32 mask = vgpu_vreg(vgpu, offset) >> 16;
284 
285 			vgpu_vreg(vgpu, offset) = (old_vreg & ~mask)
286 				| (vgpu_vreg(vgpu, offset) & mask);
287 			vgpu_sreg(vgpu, offset) = (old_sreg & ~mask)
288 				| (vgpu_sreg(vgpu, offset) & mask);
289 		}
290 	} else
291 		ret = intel_vgpu_default_mmio_write(vgpu, offset, p_data,
292 				bytes);
293 	if (ret)
294 		goto err;
295 out:
296 	intel_gvt_mmio_set_accessed(gvt, offset);
297 	mutex_unlock(&gvt->lock);
298 	return 0;
299 err:
300 	gvt_err("vgpu%d: fail to emulate MMIO write %08x len %d\n",
301 			vgpu->id, offset, bytes);
302 	mutex_unlock(&gvt->lock);
303 	return ret;
304 }
305