xref: /openbmc/linux/drivers/gpu/drm/i915/gvt/cfg_space.c (revision de6da33e)
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  *    Eddie Dong <eddie.dong@intel.com>
25  *    Jike Song <jike.song@intel.com>
26  *
27  * Contributors:
28  *    Zhi Wang <zhi.a.wang@intel.com>
29  *    Min He <min.he@intel.com>
30  *    Bing Niu <bing.niu@intel.com>
31  *
32  */
33 
34 #include "i915_drv.h"
35 #include "gvt.h"
36 
37 enum {
38 	INTEL_GVT_PCI_BAR_GTTMMIO = 0,
39 	INTEL_GVT_PCI_BAR_APERTURE,
40 	INTEL_GVT_PCI_BAR_PIO,
41 	INTEL_GVT_PCI_BAR_MAX,
42 };
43 
44 /* bitmap for writable bits (RW or RW1C bits, but cannot co-exist in one
45  * byte) byte by byte in standard pci configuration space. (not the full
46  * 256 bytes.)
47  */
48 static const u8 pci_cfg_space_rw_bmp[PCI_INTERRUPT_LINE + 4] = {
49 	[PCI_COMMAND]		= 0xff, 0x07,
50 	[PCI_STATUS]		= 0x00, 0xf9, /* the only one RW1C byte */
51 	[PCI_CACHE_LINE_SIZE]	= 0xff,
52 	[PCI_BASE_ADDRESS_0 ... PCI_CARDBUS_CIS - 1] = 0xff,
53 	[PCI_ROM_ADDRESS]	= 0x01, 0xf8, 0xff, 0xff,
54 	[PCI_INTERRUPT_LINE]	= 0xff,
55 };
56 
57 /**
58  * vgpu_pci_cfg_mem_write - write virtual cfg space memory
59  * @vgpu: target vgpu
60  * @off: offset
61  * @src: src ptr to write
62  * @bytes: number of bytes
63  *
64  * Use this function to write virtual cfg space memory.
65  * For standard cfg space, only RW bits can be changed,
66  * and we emulates the RW1C behavior of PCI_STATUS register.
67  */
68 static void vgpu_pci_cfg_mem_write(struct intel_vgpu *vgpu, unsigned int off,
69 				   u8 *src, unsigned int bytes)
70 {
71 	u8 *cfg_base = vgpu_cfg_space(vgpu);
72 	u8 mask, new, old;
73 	pci_power_t pwr;
74 	int i = 0;
75 
76 	for (; i < bytes && (off + i < sizeof(pci_cfg_space_rw_bmp)); i++) {
77 		mask = pci_cfg_space_rw_bmp[off + i];
78 		old = cfg_base[off + i];
79 		new = src[i] & mask;
80 
81 		/**
82 		 * The PCI_STATUS high byte has RW1C bits, here
83 		 * emulates clear by writing 1 for these bits.
84 		 * Writing a 0b to RW1C bits has no effect.
85 		 */
86 		if (off + i == PCI_STATUS + 1)
87 			new = (~new & old) & mask;
88 
89 		cfg_base[off + i] = (old & ~mask) | new;
90 	}
91 
92 	/* For other configuration space directly copy as it is. */
93 	if (i < bytes)
94 		memcpy(cfg_base + off + i, src + i, bytes - i);
95 
96 	if (off == vgpu->cfg_space.pmcsr_off && vgpu->cfg_space.pmcsr_off) {
97 		pwr = (pci_power_t __force)(*(u16*)(&vgpu_cfg_space(vgpu)[off])
98 			& PCI_PM_CTRL_STATE_MASK);
99 		if (pwr == PCI_D3hot)
100 			vgpu->d3_entered = true;
101 		gvt_dbg_core("vgpu-%d power status changed to %d\n",
102 			     vgpu->id, pwr);
103 	}
104 }
105 
106 /**
107  * intel_vgpu_emulate_cfg_read - emulate vGPU configuration space read
108  * @vgpu: target vgpu
109  * @offset: offset
110  * @p_data: return data ptr
111  * @bytes: number of bytes to read
112  *
113  * Returns:
114  * Zero on success, negative error code if failed.
115  */
116 int intel_vgpu_emulate_cfg_read(struct intel_vgpu *vgpu, unsigned int offset,
117 	void *p_data, unsigned int bytes)
118 {
119 	struct drm_i915_private *i915 = vgpu->gvt->gt->i915;
120 
121 	if (drm_WARN_ON(&i915->drm, bytes > 4))
122 		return -EINVAL;
123 
124 	if (drm_WARN_ON(&i915->drm,
125 			offset + bytes > vgpu->gvt->device_info.cfg_space_size))
126 		return -EINVAL;
127 
128 	memcpy(p_data, vgpu_cfg_space(vgpu) + offset, bytes);
129 	return 0;
130 }
131 
132 static int map_aperture(struct intel_vgpu *vgpu, bool map)
133 {
134 	phys_addr_t aperture_pa = vgpu_aperture_pa_base(vgpu);
135 	unsigned long aperture_sz = vgpu_aperture_sz(vgpu);
136 	u64 first_gfn;
137 	u64 val;
138 	int ret;
139 
140 	if (map == vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].tracked)
141 		return 0;
142 
143 	val = vgpu_cfg_space(vgpu)[PCI_BASE_ADDRESS_2];
144 	if (val & PCI_BASE_ADDRESS_MEM_TYPE_64)
145 		val = *(u64 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_2);
146 	else
147 		val = *(u32 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_2);
148 
149 	first_gfn = (val + vgpu_aperture_offset(vgpu)) >> PAGE_SHIFT;
150 
151 	ret = intel_gvt_hypervisor_map_gfn_to_mfn(vgpu, first_gfn,
152 						  aperture_pa >> PAGE_SHIFT,
153 						  aperture_sz >> PAGE_SHIFT,
154 						  map);
155 	if (ret)
156 		return ret;
157 
158 	vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].tracked = map;
159 	return 0;
160 }
161 
162 static int trap_gttmmio(struct intel_vgpu *vgpu, bool trap)
163 {
164 	u64 start, end;
165 	u64 val;
166 	int ret;
167 
168 	if (trap == vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].tracked)
169 		return 0;
170 
171 	val = vgpu_cfg_space(vgpu)[PCI_BASE_ADDRESS_0];
172 	if (val & PCI_BASE_ADDRESS_MEM_TYPE_64)
173 		start = *(u64 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_0);
174 	else
175 		start = *(u32 *)(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_0);
176 
177 	start &= ~GENMASK(3, 0);
178 	end = start + vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].size - 1;
179 
180 	ret = intel_gvt_hypervisor_set_trap_area(vgpu, start, end, trap);
181 	if (ret)
182 		return ret;
183 
184 	vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].tracked = trap;
185 	return 0;
186 }
187 
188 static int emulate_pci_command_write(struct intel_vgpu *vgpu,
189 	unsigned int offset, void *p_data, unsigned int bytes)
190 {
191 	u8 old = vgpu_cfg_space(vgpu)[offset];
192 	u8 new = *(u8 *)p_data;
193 	u8 changed = old ^ new;
194 	int ret;
195 
196 	vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
197 	if (!(changed & PCI_COMMAND_MEMORY))
198 		return 0;
199 
200 	if (old & PCI_COMMAND_MEMORY) {
201 		ret = trap_gttmmio(vgpu, false);
202 		if (ret)
203 			return ret;
204 		ret = map_aperture(vgpu, false);
205 		if (ret)
206 			return ret;
207 	} else {
208 		ret = trap_gttmmio(vgpu, true);
209 		if (ret)
210 			return ret;
211 		ret = map_aperture(vgpu, true);
212 		if (ret)
213 			return ret;
214 	}
215 
216 	return 0;
217 }
218 
219 static int emulate_pci_rom_bar_write(struct intel_vgpu *vgpu,
220 	unsigned int offset, void *p_data, unsigned int bytes)
221 {
222 	u32 *pval = (u32 *)(vgpu_cfg_space(vgpu) + offset);
223 	u32 new = *(u32 *)(p_data);
224 
225 	if ((new & PCI_ROM_ADDRESS_MASK) == PCI_ROM_ADDRESS_MASK)
226 		/* We don't have rom, return size of 0. */
227 		*pval = 0;
228 	else
229 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
230 	return 0;
231 }
232 
233 static int emulate_pci_bar_write(struct intel_vgpu *vgpu, unsigned int offset,
234 	void *p_data, unsigned int bytes)
235 {
236 	u32 new = *(u32 *)(p_data);
237 	bool lo = IS_ALIGNED(offset, 8);
238 	u64 size;
239 	int ret = 0;
240 	bool mmio_enabled =
241 		vgpu_cfg_space(vgpu)[PCI_COMMAND] & PCI_COMMAND_MEMORY;
242 	struct intel_vgpu_pci_bar *bars = vgpu->cfg_space.bar;
243 
244 	/*
245 	 * Power-up software can determine how much address
246 	 * space the device requires by writing a value of
247 	 * all 1's to the register and then reading the value
248 	 * back. The device will return 0's in all don't-care
249 	 * address bits.
250 	 */
251 	if (new == 0xffffffff) {
252 		switch (offset) {
253 		case PCI_BASE_ADDRESS_0:
254 		case PCI_BASE_ADDRESS_1:
255 			size = ~(bars[INTEL_GVT_PCI_BAR_GTTMMIO].size -1);
256 			intel_vgpu_write_pci_bar(vgpu, offset,
257 						size >> (lo ? 0 : 32), lo);
258 			/*
259 			 * Untrap the BAR, since guest hasn't configured a
260 			 * valid GPA
261 			 */
262 			ret = trap_gttmmio(vgpu, false);
263 			break;
264 		case PCI_BASE_ADDRESS_2:
265 		case PCI_BASE_ADDRESS_3:
266 			size = ~(bars[INTEL_GVT_PCI_BAR_APERTURE].size -1);
267 			intel_vgpu_write_pci_bar(vgpu, offset,
268 						size >> (lo ? 0 : 32), lo);
269 			ret = map_aperture(vgpu, false);
270 			break;
271 		default:
272 			/* Unimplemented BARs */
273 			intel_vgpu_write_pci_bar(vgpu, offset, 0x0, false);
274 		}
275 	} else {
276 		switch (offset) {
277 		case PCI_BASE_ADDRESS_0:
278 		case PCI_BASE_ADDRESS_1:
279 			/*
280 			 * Untrap the old BAR first, since guest has
281 			 * re-configured the BAR
282 			 */
283 			trap_gttmmio(vgpu, false);
284 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
285 			ret = trap_gttmmio(vgpu, mmio_enabled);
286 			break;
287 		case PCI_BASE_ADDRESS_2:
288 		case PCI_BASE_ADDRESS_3:
289 			map_aperture(vgpu, false);
290 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
291 			ret = map_aperture(vgpu, mmio_enabled);
292 			break;
293 		default:
294 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
295 		}
296 	}
297 	return ret;
298 }
299 
300 /**
301  * intel_vgpu_emulate_cfg_read - emulate vGPU configuration space write
302  * @vgpu: target vgpu
303  * @offset: offset
304  * @p_data: write data ptr
305  * @bytes: number of bytes to write
306  *
307  * Returns:
308  * Zero on success, negative error code if failed.
309  */
310 int intel_vgpu_emulate_cfg_write(struct intel_vgpu *vgpu, unsigned int offset,
311 	void *p_data, unsigned int bytes)
312 {
313 	struct drm_i915_private *i915 = vgpu->gvt->gt->i915;
314 	int ret;
315 
316 	if (drm_WARN_ON(&i915->drm, bytes > 4))
317 		return -EINVAL;
318 
319 	if (drm_WARN_ON(&i915->drm,
320 			offset + bytes > vgpu->gvt->device_info.cfg_space_size))
321 		return -EINVAL;
322 
323 	/* First check if it's PCI_COMMAND */
324 	if (IS_ALIGNED(offset, 2) && offset == PCI_COMMAND) {
325 		if (drm_WARN_ON(&i915->drm, bytes > 2))
326 			return -EINVAL;
327 		return emulate_pci_command_write(vgpu, offset, p_data, bytes);
328 	}
329 
330 	switch (rounddown(offset, 4)) {
331 	case PCI_ROM_ADDRESS:
332 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
333 			return -EINVAL;
334 		return emulate_pci_rom_bar_write(vgpu, offset, p_data, bytes);
335 
336 	case PCI_BASE_ADDRESS_0 ... PCI_BASE_ADDRESS_5:
337 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
338 			return -EINVAL;
339 		return emulate_pci_bar_write(vgpu, offset, p_data, bytes);
340 
341 	case INTEL_GVT_PCI_SWSCI:
342 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
343 			return -EINVAL;
344 		ret = intel_vgpu_emulate_opregion_request(vgpu, *(u32 *)p_data);
345 		if (ret)
346 			return ret;
347 		break;
348 
349 	case INTEL_GVT_PCI_OPREGION:
350 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
351 			return -EINVAL;
352 		ret = intel_vgpu_opregion_base_write_handler(vgpu,
353 						   *(u32 *)p_data);
354 		if (ret)
355 			return ret;
356 
357 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
358 		break;
359 	default:
360 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
361 		break;
362 	}
363 	return 0;
364 }
365 
366 /**
367  * intel_vgpu_init_cfg_space - init vGPU configuration space when create vGPU
368  *
369  * @vgpu: a vGPU
370  * @primary: is the vGPU presented as primary
371  *
372  */
373 void intel_vgpu_init_cfg_space(struct intel_vgpu *vgpu,
374 			       bool primary)
375 {
376 	struct intel_gvt *gvt = vgpu->gvt;
377 	struct pci_dev *pdev = to_pci_dev(gvt->gt->i915->drm.dev);
378 	const struct intel_gvt_device_info *info = &gvt->device_info;
379 	u16 *gmch_ctl;
380 	u8 next;
381 
382 	memcpy(vgpu_cfg_space(vgpu), gvt->firmware.cfg_space,
383 	       info->cfg_space_size);
384 
385 	if (!primary) {
386 		vgpu_cfg_space(vgpu)[PCI_CLASS_DEVICE] =
387 			INTEL_GVT_PCI_CLASS_VGA_OTHER;
388 		vgpu_cfg_space(vgpu)[PCI_CLASS_PROG] =
389 			INTEL_GVT_PCI_CLASS_VGA_OTHER;
390 	}
391 
392 	/* Show guest that there isn't any stolen memory.*/
393 	gmch_ctl = (u16 *)(vgpu_cfg_space(vgpu) + INTEL_GVT_PCI_GMCH_CONTROL);
394 	*gmch_ctl &= ~(BDW_GMCH_GMS_MASK << BDW_GMCH_GMS_SHIFT);
395 
396 	intel_vgpu_write_pci_bar(vgpu, PCI_BASE_ADDRESS_2,
397 				 gvt_aperture_pa_base(gvt), true);
398 
399 	vgpu_cfg_space(vgpu)[PCI_COMMAND] &= ~(PCI_COMMAND_IO
400 					     | PCI_COMMAND_MEMORY
401 					     | PCI_COMMAND_MASTER);
402 	/*
403 	 * Clear the bar upper 32bit and let guest to assign the new value
404 	 */
405 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_1, 0, 4);
406 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_3, 0, 4);
407 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_4, 0, 8);
408 	memset(vgpu_cfg_space(vgpu) + INTEL_GVT_PCI_OPREGION, 0, 4);
409 
410 	vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].size =
411 		pci_resource_len(pdev, 0);
412 	vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].size =
413 		pci_resource_len(pdev, 2);
414 
415 	memset(vgpu_cfg_space(vgpu) + PCI_ROM_ADDRESS, 0, 4);
416 
417 	/* PM Support */
418 	vgpu->cfg_space.pmcsr_off = 0;
419 	if (vgpu_cfg_space(vgpu)[PCI_STATUS] & PCI_STATUS_CAP_LIST) {
420 		next = vgpu_cfg_space(vgpu)[PCI_CAPABILITY_LIST];
421 		do {
422 			if (vgpu_cfg_space(vgpu)[next + PCI_CAP_LIST_ID] == PCI_CAP_ID_PM) {
423 				vgpu->cfg_space.pmcsr_off = next + PCI_PM_CTRL;
424 				break;
425 			}
426 			next = vgpu_cfg_space(vgpu)[next + PCI_CAP_LIST_NEXT];
427 		} while (next);
428 	}
429 }
430 
431 /**
432  * intel_vgpu_reset_cfg_space - reset vGPU configuration space
433  *
434  * @vgpu: a vGPU
435  *
436  */
437 void intel_vgpu_reset_cfg_space(struct intel_vgpu *vgpu)
438 {
439 	u8 cmd = vgpu_cfg_space(vgpu)[PCI_COMMAND];
440 	bool primary = vgpu_cfg_space(vgpu)[PCI_CLASS_DEVICE] !=
441 				INTEL_GVT_PCI_CLASS_VGA_OTHER;
442 
443 	if (cmd & PCI_COMMAND_MEMORY) {
444 		trap_gttmmio(vgpu, false);
445 		map_aperture(vgpu, false);
446 	}
447 
448 	/**
449 	 * Currently we only do such reset when vGPU is not
450 	 * owned by any VM, so we simply restore entire cfg
451 	 * space to default value.
452 	 */
453 	intel_vgpu_init_cfg_space(vgpu, primary);
454 }
455