xref: /openbmc/linux/drivers/gpu/drm/i915/gvt/mmio.c (revision 7bcae826)
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 	if (!intel_gvt_mmio_is_unalign(gvt, offset)) {
129 		if (WARN_ON(!IS_ALIGNED(offset, bytes)))
130 			goto err;
131 	}
132 
133 	mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
134 	if (mmio) {
135 		if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
136 			if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
137 				goto err;
138 			if (WARN_ON(mmio->offset != offset))
139 				goto err;
140 		}
141 		ret = mmio->read(vgpu, offset, p_data, bytes);
142 	} else {
143 		ret = intel_vgpu_default_mmio_read(vgpu, offset, p_data, bytes);
144 
145 		if (!vgpu->mmio.disable_warn_untrack) {
146 			gvt_err("vgpu%d: read untracked MMIO %x(%dB) val %x\n",
147 				vgpu->id, offset, bytes, *(u32 *)p_data);
148 
149 			if (offset == 0x206c) {
150 				gvt_err("------------------------------------------\n");
151 				gvt_err("vgpu%d: likely triggers a gfx reset\n",
152 					vgpu->id);
153 				gvt_err("------------------------------------------\n");
154 				vgpu->mmio.disable_warn_untrack = true;
155 			}
156 		}
157 	}
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(struct intel_vgpu *vgpu, uint64_t pa,
183 		void *p_data, unsigned int bytes)
184 {
185 	struct intel_gvt *gvt = vgpu->gvt;
186 	struct intel_gvt_mmio_info *mmio;
187 	unsigned int offset = 0;
188 	u32 old_vreg = 0, old_sreg = 0;
189 	int ret = -EINVAL;
190 
191 	mutex_lock(&gvt->lock);
192 
193 	if (atomic_read(&vgpu->gtt.n_write_protected_guest_page)) {
194 		struct intel_vgpu_guest_page *gp;
195 
196 		gp = intel_vgpu_find_guest_page(vgpu, pa >> PAGE_SHIFT);
197 		if (gp) {
198 			ret = gp->handler(gp, pa, p_data, bytes);
199 			if (ret) {
200 				gvt_err("vgpu%d: guest page write error %d, "
201 					"gfn 0x%lx, pa 0x%llx, var 0x%x, len %d\n",
202 					vgpu->id, ret,
203 					gp->gfn, pa, *(u32 *)p_data, bytes);
204 			}
205 			mutex_unlock(&gvt->lock);
206 			return ret;
207 		}
208 	}
209 
210 	offset = intel_vgpu_gpa_to_mmio_offset(vgpu, pa);
211 
212 	if (WARN_ON(bytes > 8))
213 		goto err;
214 
215 	if (reg_is_gtt(gvt, offset)) {
216 		if (WARN_ON(!IS_ALIGNED(offset, 4) && !IS_ALIGNED(offset, 8)))
217 			goto err;
218 		if (WARN_ON(bytes != 4 && bytes != 8))
219 			goto err;
220 		if (WARN_ON(!reg_is_gtt(gvt, offset + bytes - 1)))
221 			goto err;
222 
223 		ret = intel_vgpu_emulate_gtt_mmio_write(vgpu, offset,
224 				p_data, bytes);
225 		if (ret)
226 			goto err;
227 		mutex_unlock(&gvt->lock);
228 		return ret;
229 	}
230 
231 	if (WARN_ON_ONCE(!reg_is_mmio(gvt, offset))) {
232 		ret = intel_gvt_hypervisor_write_gpa(vgpu, pa, p_data, bytes);
233 		mutex_unlock(&gvt->lock);
234 		return ret;
235 	}
236 
237 	mmio = intel_gvt_find_mmio_info(gvt, rounddown(offset, 4));
238 	if (!mmio && !vgpu->mmio.disable_warn_untrack)
239 		gvt_err("vgpu%d: write untracked MMIO %x len %d val %x\n",
240 				vgpu->id, offset, bytes, *(u32 *)p_data);
241 
242 	if (!intel_gvt_mmio_is_unalign(gvt, offset)) {
243 		if (WARN_ON(!IS_ALIGNED(offset, bytes)))
244 			goto err;
245 	}
246 
247 	if (mmio) {
248 		u64 ro_mask = mmio->ro_mask;
249 
250 		if (!intel_gvt_mmio_is_unalign(gvt, mmio->offset)) {
251 			if (WARN_ON(offset + bytes > mmio->offset + mmio->size))
252 				goto err;
253 			if (WARN_ON(mmio->offset != offset))
254 				goto err;
255 		}
256 
257 		if (intel_gvt_mmio_has_mode_mask(gvt, mmio->offset)) {
258 			old_vreg = vgpu_vreg(vgpu, offset);
259 			old_sreg = vgpu_sreg(vgpu, offset);
260 		}
261 
262 		if (!ro_mask) {
263 			ret = mmio->write(vgpu, offset, p_data, bytes);
264 		} else {
265 			/* Protect RO bits like HW */
266 			u64 data = 0;
267 
268 			/* all register bits are RO. */
269 			if (ro_mask == ~(u64)0) {
270 				gvt_err("vgpu%d: try to write RO reg %x\n",
271 						vgpu->id, offset);
272 				ret = 0;
273 				goto out;
274 			}
275 			/* keep the RO bits in the virtual register */
276 			memcpy(&data, p_data, bytes);
277 			data &= ~mmio->ro_mask;
278 			data |= vgpu_vreg(vgpu, offset) & mmio->ro_mask;
279 			ret = mmio->write(vgpu, offset, &data, bytes);
280 		}
281 
282 		/* higher 16bits of mode ctl regs are mask bits for change */
283 		if (intel_gvt_mmio_has_mode_mask(gvt, mmio->offset)) {
284 			u32 mask = vgpu_vreg(vgpu, offset) >> 16;
285 
286 			vgpu_vreg(vgpu, offset) = (old_vreg & ~mask)
287 				| (vgpu_vreg(vgpu, offset) & mask);
288 			vgpu_sreg(vgpu, offset) = (old_sreg & ~mask)
289 				| (vgpu_sreg(vgpu, offset) & mask);
290 		}
291 	} else
292 		ret = intel_vgpu_default_mmio_write(vgpu, offset, p_data,
293 				bytes);
294 	if (ret)
295 		goto err;
296 out:
297 	intel_gvt_mmio_set_accessed(gvt, offset);
298 	mutex_unlock(&gvt->lock);
299 	return 0;
300 err:
301 	gvt_err("vgpu%d: fail to emulate MMIO write %08x len %d\n",
302 			vgpu->id, offset, bytes);
303 	mutex_unlock(&gvt->lock);
304 	return ret;
305 }
306 
307 
308 /**
309  * intel_vgpu_reset_mmio - reset virtual MMIO space
310  * @vgpu: a vGPU
311  *
312  */
313 void intel_vgpu_reset_mmio(struct intel_vgpu *vgpu)
314 {
315 	struct intel_gvt *gvt = vgpu->gvt;
316 	const struct intel_gvt_device_info *info = &gvt->device_info;
317 
318 	memcpy(vgpu->mmio.vreg, gvt->firmware.mmio, info->mmio_size);
319 	memcpy(vgpu->mmio.sreg, gvt->firmware.mmio, info->mmio_size);
320 
321 	vgpu_vreg(vgpu, GEN6_GT_THREAD_STATUS_REG) = 0;
322 
323 	/* set the bit 0:2(Core C-State ) to C0 */
324 	vgpu_vreg(vgpu, GEN6_GT_CORE_STATUS) = 0;
325 }
326 
327 /**
328  * intel_vgpu_init_mmio - init MMIO  space
329  * @vgpu: a vGPU
330  *
331  * Returns:
332  * Zero on success, negative error code if failed
333  */
334 int intel_vgpu_init_mmio(struct intel_vgpu *vgpu)
335 {
336 	const struct intel_gvt_device_info *info = &vgpu->gvt->device_info;
337 
338 	vgpu->mmio.vreg = vzalloc(info->mmio_size * 2);
339 	if (!vgpu->mmio.vreg)
340 		return -ENOMEM;
341 
342 	vgpu->mmio.sreg = vgpu->mmio.vreg + info->mmio_size;
343 
344 	intel_vgpu_reset_mmio(vgpu);
345 
346 	return 0;
347 }
348 
349 /**
350  * intel_vgpu_clean_mmio - clean MMIO space
351  * @vgpu: a vGPU
352  *
353  */
354 void intel_vgpu_clean_mmio(struct intel_vgpu *vgpu)
355 {
356 	vfree(vgpu->mmio.vreg);
357 	vgpu->mmio.vreg = vgpu->mmio.sreg = NULL;
358 }
359