xref: /openbmc/linux/drivers/gpu/drm/i915/gvt/cfg_space.c (revision 0352f880)
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 #include "intel_pci_config.h"
37 
38 enum {
39 	INTEL_GVT_PCI_BAR_GTTMMIO = 0,
40 	INTEL_GVT_PCI_BAR_APERTURE,
41 	INTEL_GVT_PCI_BAR_PIO,
42 	INTEL_GVT_PCI_BAR_MAX,
43 };
44 
45 /* bitmap for writable bits (RW or RW1C bits, but cannot co-exist in one
46  * byte) byte by byte in standard pci configuration space. (not the full
47  * 256 bytes.)
48  */
49 static const u8 pci_cfg_space_rw_bmp[PCI_INTERRUPT_LINE + 4] = {
50 	[PCI_COMMAND]		= 0xff, 0x07,
51 	[PCI_STATUS]		= 0x00, 0xf9, /* the only one RW1C byte */
52 	[PCI_CACHE_LINE_SIZE]	= 0xff,
53 	[PCI_BASE_ADDRESS_0 ... PCI_CARDBUS_CIS - 1] = 0xff,
54 	[PCI_ROM_ADDRESS]	= 0x01, 0xf8, 0xff, 0xff,
55 	[PCI_INTERRUPT_LINE]	= 0xff,
56 };
57 
58 /**
59  * vgpu_pci_cfg_mem_write - write virtual cfg space memory
60  * @vgpu: target vgpu
61  * @off: offset
62  * @src: src ptr to write
63  * @bytes: number of bytes
64  *
65  * Use this function to write virtual cfg space memory.
66  * For standard cfg space, only RW bits can be changed,
67  * and we emulates the RW1C behavior of PCI_STATUS register.
68  */
69 static void vgpu_pci_cfg_mem_write(struct intel_vgpu *vgpu, unsigned int off,
70 				   u8 *src, unsigned int bytes)
71 {
72 	u8 *cfg_base = vgpu_cfg_space(vgpu);
73 	u8 mask, new, old;
74 	pci_power_t pwr;
75 	int i = 0;
76 
77 	for (; i < bytes && (off + i < sizeof(pci_cfg_space_rw_bmp)); i++) {
78 		mask = pci_cfg_space_rw_bmp[off + i];
79 		old = cfg_base[off + i];
80 		new = src[i] & mask;
81 
82 		/**
83 		 * The PCI_STATUS high byte has RW1C bits, here
84 		 * emulates clear by writing 1 for these bits.
85 		 * Writing a 0b to RW1C bits has no effect.
86 		 */
87 		if (off + i == PCI_STATUS + 1)
88 			new = (~new & old) & mask;
89 
90 		cfg_base[off + i] = (old & ~mask) | new;
91 	}
92 
93 	/* For other configuration space directly copy as it is. */
94 	if (i < bytes)
95 		memcpy(cfg_base + off + i, src + i, bytes - i);
96 
97 	if (off == vgpu->cfg_space.pmcsr_off && vgpu->cfg_space.pmcsr_off) {
98 		pwr = (pci_power_t __force)(*(u16*)(&vgpu_cfg_space(vgpu)[off])
99 			& PCI_PM_CTRL_STATE_MASK);
100 		if (pwr == PCI_D3hot)
101 			vgpu->d3_entered = true;
102 		gvt_dbg_core("vgpu-%d power status changed to %d\n",
103 			     vgpu->id, pwr);
104 	}
105 }
106 
107 /**
108  * intel_vgpu_emulate_cfg_read - emulate vGPU configuration space read
109  * @vgpu: target vgpu
110  * @offset: offset
111  * @p_data: return data ptr
112  * @bytes: number of bytes to read
113  *
114  * Returns:
115  * Zero on success, negative error code if failed.
116  */
117 int intel_vgpu_emulate_cfg_read(struct intel_vgpu *vgpu, unsigned int offset,
118 	void *p_data, unsigned int bytes)
119 {
120 	struct drm_i915_private *i915 = vgpu->gvt->gt->i915;
121 
122 	if (drm_WARN_ON(&i915->drm, bytes > 4))
123 		return -EINVAL;
124 
125 	if (drm_WARN_ON(&i915->drm,
126 			offset + bytes > vgpu->gvt->device_info.cfg_space_size))
127 		return -EINVAL;
128 
129 	memcpy(p_data, vgpu_cfg_space(vgpu) + offset, bytes);
130 	return 0;
131 }
132 
133 static void map_aperture(struct intel_vgpu *vgpu, bool map)
134 {
135 	if (map != vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].tracked)
136 		vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].tracked = map;
137 }
138 
139 static void trap_gttmmio(struct intel_vgpu *vgpu, bool trap)
140 {
141 	if (trap != vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].tracked)
142 		vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].tracked = trap;
143 }
144 
145 static int emulate_pci_command_write(struct intel_vgpu *vgpu,
146 	unsigned int offset, void *p_data, unsigned int bytes)
147 {
148 	u8 old = vgpu_cfg_space(vgpu)[offset];
149 	u8 new = *(u8 *)p_data;
150 	u8 changed = old ^ new;
151 
152 	vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
153 	if (!(changed & PCI_COMMAND_MEMORY))
154 		return 0;
155 
156 	if (old & PCI_COMMAND_MEMORY) {
157 		trap_gttmmio(vgpu, false);
158 		map_aperture(vgpu, false);
159 	} else {
160 		trap_gttmmio(vgpu, true);
161 		map_aperture(vgpu, true);
162 	}
163 
164 	return 0;
165 }
166 
167 static int emulate_pci_rom_bar_write(struct intel_vgpu *vgpu,
168 	unsigned int offset, void *p_data, unsigned int bytes)
169 {
170 	u32 *pval = (u32 *)(vgpu_cfg_space(vgpu) + offset);
171 	u32 new = *(u32 *)(p_data);
172 
173 	if ((new & PCI_ROM_ADDRESS_MASK) == PCI_ROM_ADDRESS_MASK)
174 		/* We don't have rom, return size of 0. */
175 		*pval = 0;
176 	else
177 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
178 	return 0;
179 }
180 
181 static void emulate_pci_bar_write(struct intel_vgpu *vgpu, unsigned int offset,
182 	void *p_data, unsigned int bytes)
183 {
184 	u32 new = *(u32 *)(p_data);
185 	bool lo = IS_ALIGNED(offset, 8);
186 	u64 size;
187 	bool mmio_enabled =
188 		vgpu_cfg_space(vgpu)[PCI_COMMAND] & PCI_COMMAND_MEMORY;
189 	struct intel_vgpu_pci_bar *bars = vgpu->cfg_space.bar;
190 
191 	/*
192 	 * Power-up software can determine how much address
193 	 * space the device requires by writing a value of
194 	 * all 1's to the register and then reading the value
195 	 * back. The device will return 0's in all don't-care
196 	 * address bits.
197 	 */
198 	if (new == 0xffffffff) {
199 		switch (offset) {
200 		case PCI_BASE_ADDRESS_0:
201 		case PCI_BASE_ADDRESS_1:
202 			size = ~(bars[INTEL_GVT_PCI_BAR_GTTMMIO].size -1);
203 			intel_vgpu_write_pci_bar(vgpu, offset,
204 						size >> (lo ? 0 : 32), lo);
205 			/*
206 			 * Untrap the BAR, since guest hasn't configured a
207 			 * valid GPA
208 			 */
209 			trap_gttmmio(vgpu, false);
210 			break;
211 		case PCI_BASE_ADDRESS_2:
212 		case PCI_BASE_ADDRESS_3:
213 			size = ~(bars[INTEL_GVT_PCI_BAR_APERTURE].size -1);
214 			intel_vgpu_write_pci_bar(vgpu, offset,
215 						size >> (lo ? 0 : 32), lo);
216 			map_aperture(vgpu, false);
217 			break;
218 		default:
219 			/* Unimplemented BARs */
220 			intel_vgpu_write_pci_bar(vgpu, offset, 0x0, false);
221 		}
222 	} else {
223 		switch (offset) {
224 		case PCI_BASE_ADDRESS_0:
225 		case PCI_BASE_ADDRESS_1:
226 			/*
227 			 * Untrap the old BAR first, since guest has
228 			 * re-configured the BAR
229 			 */
230 			trap_gttmmio(vgpu, false);
231 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
232 			trap_gttmmio(vgpu, mmio_enabled);
233 			break;
234 		case PCI_BASE_ADDRESS_2:
235 		case PCI_BASE_ADDRESS_3:
236 			map_aperture(vgpu, false);
237 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
238 			map_aperture(vgpu, mmio_enabled);
239 			break;
240 		default:
241 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
242 		}
243 	}
244 }
245 
246 /**
247  * intel_vgpu_emulate_cfg_read - emulate vGPU configuration space write
248  * @vgpu: target vgpu
249  * @offset: offset
250  * @p_data: write data ptr
251  * @bytes: number of bytes to write
252  *
253  * Returns:
254  * Zero on success, negative error code if failed.
255  */
256 int intel_vgpu_emulate_cfg_write(struct intel_vgpu *vgpu, unsigned int offset,
257 	void *p_data, unsigned int bytes)
258 {
259 	struct drm_i915_private *i915 = vgpu->gvt->gt->i915;
260 	int ret;
261 
262 	if (drm_WARN_ON(&i915->drm, bytes > 4))
263 		return -EINVAL;
264 
265 	if (drm_WARN_ON(&i915->drm,
266 			offset + bytes > vgpu->gvt->device_info.cfg_space_size))
267 		return -EINVAL;
268 
269 	/* First check if it's PCI_COMMAND */
270 	if (IS_ALIGNED(offset, 2) && offset == PCI_COMMAND) {
271 		if (drm_WARN_ON(&i915->drm, bytes > 2))
272 			return -EINVAL;
273 		return emulate_pci_command_write(vgpu, offset, p_data, bytes);
274 	}
275 
276 	switch (rounddown(offset, 4)) {
277 	case PCI_ROM_ADDRESS:
278 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
279 			return -EINVAL;
280 		return emulate_pci_rom_bar_write(vgpu, offset, p_data, bytes);
281 
282 	case PCI_BASE_ADDRESS_0 ... PCI_BASE_ADDRESS_5:
283 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
284 			return -EINVAL;
285 		emulate_pci_bar_write(vgpu, offset, p_data, bytes);
286 		break;
287 	case INTEL_GVT_PCI_SWSCI:
288 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
289 			return -EINVAL;
290 		ret = intel_vgpu_emulate_opregion_request(vgpu, *(u32 *)p_data);
291 		if (ret)
292 			return ret;
293 		break;
294 
295 	case INTEL_GVT_PCI_OPREGION:
296 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
297 			return -EINVAL;
298 		ret = intel_vgpu_opregion_base_write_handler(vgpu,
299 						   *(u32 *)p_data);
300 		if (ret)
301 			return ret;
302 
303 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
304 		break;
305 	default:
306 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
307 		break;
308 	}
309 	return 0;
310 }
311 
312 /**
313  * intel_vgpu_init_cfg_space - init vGPU configuration space when create vGPU
314  *
315  * @vgpu: a vGPU
316  * @primary: is the vGPU presented as primary
317  *
318  */
319 void intel_vgpu_init_cfg_space(struct intel_vgpu *vgpu,
320 			       bool primary)
321 {
322 	struct intel_gvt *gvt = vgpu->gvt;
323 	struct pci_dev *pdev = to_pci_dev(gvt->gt->i915->drm.dev);
324 	const struct intel_gvt_device_info *info = &gvt->device_info;
325 	u16 *gmch_ctl;
326 	u8 next;
327 
328 	memcpy(vgpu_cfg_space(vgpu), gvt->firmware.cfg_space,
329 	       info->cfg_space_size);
330 
331 	if (!primary) {
332 		vgpu_cfg_space(vgpu)[PCI_CLASS_DEVICE] =
333 			INTEL_GVT_PCI_CLASS_VGA_OTHER;
334 		vgpu_cfg_space(vgpu)[PCI_CLASS_PROG] =
335 			INTEL_GVT_PCI_CLASS_VGA_OTHER;
336 	}
337 
338 	/* Show guest that there isn't any stolen memory.*/
339 	gmch_ctl = (u16 *)(vgpu_cfg_space(vgpu) + INTEL_GVT_PCI_GMCH_CONTROL);
340 	*gmch_ctl &= ~(BDW_GMCH_GMS_MASK << BDW_GMCH_GMS_SHIFT);
341 
342 	intel_vgpu_write_pci_bar(vgpu, PCI_BASE_ADDRESS_2,
343 				 gvt_aperture_pa_base(gvt), true);
344 
345 	vgpu_cfg_space(vgpu)[PCI_COMMAND] &= ~(PCI_COMMAND_IO
346 					     | PCI_COMMAND_MEMORY
347 					     | PCI_COMMAND_MASTER);
348 	/*
349 	 * Clear the bar upper 32bit and let guest to assign the new value
350 	 */
351 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_1, 0, 4);
352 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_3, 0, 4);
353 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_4, 0, 8);
354 	memset(vgpu_cfg_space(vgpu) + INTEL_GVT_PCI_OPREGION, 0, 4);
355 
356 	vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].size =
357 		pci_resource_len(pdev, GTTMMADR_BAR);
358 	vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].size =
359 		pci_resource_len(pdev, GTT_APERTURE_BAR);
360 
361 	memset(vgpu_cfg_space(vgpu) + PCI_ROM_ADDRESS, 0, 4);
362 
363 	/* PM Support */
364 	vgpu->cfg_space.pmcsr_off = 0;
365 	if (vgpu_cfg_space(vgpu)[PCI_STATUS] & PCI_STATUS_CAP_LIST) {
366 		next = vgpu_cfg_space(vgpu)[PCI_CAPABILITY_LIST];
367 		do {
368 			if (vgpu_cfg_space(vgpu)[next + PCI_CAP_LIST_ID] == PCI_CAP_ID_PM) {
369 				vgpu->cfg_space.pmcsr_off = next + PCI_PM_CTRL;
370 				break;
371 			}
372 			next = vgpu_cfg_space(vgpu)[next + PCI_CAP_LIST_NEXT];
373 		} while (next);
374 	}
375 }
376 
377 /**
378  * intel_vgpu_reset_cfg_space - reset vGPU configuration space
379  *
380  * @vgpu: a vGPU
381  *
382  */
383 void intel_vgpu_reset_cfg_space(struct intel_vgpu *vgpu)
384 {
385 	u8 cmd = vgpu_cfg_space(vgpu)[PCI_COMMAND];
386 	bool primary = vgpu_cfg_space(vgpu)[PCI_CLASS_DEVICE] !=
387 				INTEL_GVT_PCI_CLASS_VGA_OTHER;
388 
389 	if (cmd & PCI_COMMAND_MEMORY) {
390 		trap_gttmmio(vgpu, false);
391 		map_aperture(vgpu, false);
392 	}
393 
394 	/**
395 	 * Currently we only do such reset when vGPU is not
396 	 * owned by any VM, so we simply restore entire cfg
397 	 * space to default value.
398 	 */
399 	intel_vgpu_init_cfg_space(vgpu, primary);
400 }
401