xref: /openbmc/linux/drivers/gpu/drm/i915/gvt/cfg_space.c (revision c4e78957)
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 void map_aperture(struct intel_vgpu *vgpu, bool map)
133 {
134 	if (map != vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].tracked)
135 		vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].tracked = map;
136 }
137 
138 static void trap_gttmmio(struct intel_vgpu *vgpu, bool trap)
139 {
140 	if (trap != vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].tracked)
141 		vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].tracked = trap;
142 }
143 
144 static int emulate_pci_command_write(struct intel_vgpu *vgpu,
145 	unsigned int offset, void *p_data, unsigned int bytes)
146 {
147 	u8 old = vgpu_cfg_space(vgpu)[offset];
148 	u8 new = *(u8 *)p_data;
149 	u8 changed = old ^ new;
150 
151 	vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
152 	if (!(changed & PCI_COMMAND_MEMORY))
153 		return 0;
154 
155 	if (old & PCI_COMMAND_MEMORY) {
156 		trap_gttmmio(vgpu, false);
157 		map_aperture(vgpu, false);
158 	} else {
159 		trap_gttmmio(vgpu, true);
160 		map_aperture(vgpu, true);
161 	}
162 
163 	return 0;
164 }
165 
166 static int emulate_pci_rom_bar_write(struct intel_vgpu *vgpu,
167 	unsigned int offset, void *p_data, unsigned int bytes)
168 {
169 	u32 *pval = (u32 *)(vgpu_cfg_space(vgpu) + offset);
170 	u32 new = *(u32 *)(p_data);
171 
172 	if ((new & PCI_ROM_ADDRESS_MASK) == PCI_ROM_ADDRESS_MASK)
173 		/* We don't have rom, return size of 0. */
174 		*pval = 0;
175 	else
176 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
177 	return 0;
178 }
179 
180 static void emulate_pci_bar_write(struct intel_vgpu *vgpu, unsigned int offset,
181 	void *p_data, unsigned int bytes)
182 {
183 	u32 new = *(u32 *)(p_data);
184 	bool lo = IS_ALIGNED(offset, 8);
185 	u64 size;
186 	bool mmio_enabled =
187 		vgpu_cfg_space(vgpu)[PCI_COMMAND] & PCI_COMMAND_MEMORY;
188 	struct intel_vgpu_pci_bar *bars = vgpu->cfg_space.bar;
189 
190 	/*
191 	 * Power-up software can determine how much address
192 	 * space the device requires by writing a value of
193 	 * all 1's to the register and then reading the value
194 	 * back. The device will return 0's in all don't-care
195 	 * address bits.
196 	 */
197 	if (new == 0xffffffff) {
198 		switch (offset) {
199 		case PCI_BASE_ADDRESS_0:
200 		case PCI_BASE_ADDRESS_1:
201 			size = ~(bars[INTEL_GVT_PCI_BAR_GTTMMIO].size -1);
202 			intel_vgpu_write_pci_bar(vgpu, offset,
203 						size >> (lo ? 0 : 32), lo);
204 			/*
205 			 * Untrap the BAR, since guest hasn't configured a
206 			 * valid GPA
207 			 */
208 			trap_gttmmio(vgpu, false);
209 			break;
210 		case PCI_BASE_ADDRESS_2:
211 		case PCI_BASE_ADDRESS_3:
212 			size = ~(bars[INTEL_GVT_PCI_BAR_APERTURE].size -1);
213 			intel_vgpu_write_pci_bar(vgpu, offset,
214 						size >> (lo ? 0 : 32), lo);
215 			map_aperture(vgpu, false);
216 			break;
217 		default:
218 			/* Unimplemented BARs */
219 			intel_vgpu_write_pci_bar(vgpu, offset, 0x0, false);
220 		}
221 	} else {
222 		switch (offset) {
223 		case PCI_BASE_ADDRESS_0:
224 		case PCI_BASE_ADDRESS_1:
225 			/*
226 			 * Untrap the old BAR first, since guest has
227 			 * re-configured the BAR
228 			 */
229 			trap_gttmmio(vgpu, false);
230 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
231 			trap_gttmmio(vgpu, mmio_enabled);
232 			break;
233 		case PCI_BASE_ADDRESS_2:
234 		case PCI_BASE_ADDRESS_3:
235 			map_aperture(vgpu, false);
236 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
237 			map_aperture(vgpu, mmio_enabled);
238 			break;
239 		default:
240 			intel_vgpu_write_pci_bar(vgpu, offset, new, lo);
241 		}
242 	}
243 }
244 
245 /**
246  * intel_vgpu_emulate_cfg_read - emulate vGPU configuration space write
247  * @vgpu: target vgpu
248  * @offset: offset
249  * @p_data: write data ptr
250  * @bytes: number of bytes to write
251  *
252  * Returns:
253  * Zero on success, negative error code if failed.
254  */
255 int intel_vgpu_emulate_cfg_write(struct intel_vgpu *vgpu, unsigned int offset,
256 	void *p_data, unsigned int bytes)
257 {
258 	struct drm_i915_private *i915 = vgpu->gvt->gt->i915;
259 	int ret;
260 
261 	if (drm_WARN_ON(&i915->drm, bytes > 4))
262 		return -EINVAL;
263 
264 	if (drm_WARN_ON(&i915->drm,
265 			offset + bytes > vgpu->gvt->device_info.cfg_space_size))
266 		return -EINVAL;
267 
268 	/* First check if it's PCI_COMMAND */
269 	if (IS_ALIGNED(offset, 2) && offset == PCI_COMMAND) {
270 		if (drm_WARN_ON(&i915->drm, bytes > 2))
271 			return -EINVAL;
272 		return emulate_pci_command_write(vgpu, offset, p_data, bytes);
273 	}
274 
275 	switch (rounddown(offset, 4)) {
276 	case PCI_ROM_ADDRESS:
277 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
278 			return -EINVAL;
279 		return emulate_pci_rom_bar_write(vgpu, offset, p_data, bytes);
280 
281 	case PCI_BASE_ADDRESS_0 ... PCI_BASE_ADDRESS_5:
282 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
283 			return -EINVAL;
284 		emulate_pci_bar_write(vgpu, offset, p_data, bytes);
285 		break;
286 	case INTEL_GVT_PCI_SWSCI:
287 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
288 			return -EINVAL;
289 		ret = intel_vgpu_emulate_opregion_request(vgpu, *(u32 *)p_data);
290 		if (ret)
291 			return ret;
292 		break;
293 
294 	case INTEL_GVT_PCI_OPREGION:
295 		if (drm_WARN_ON(&i915->drm, !IS_ALIGNED(offset, 4)))
296 			return -EINVAL;
297 		ret = intel_vgpu_opregion_base_write_handler(vgpu,
298 						   *(u32 *)p_data);
299 		if (ret)
300 			return ret;
301 
302 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
303 		break;
304 	default:
305 		vgpu_pci_cfg_mem_write(vgpu, offset, p_data, bytes);
306 		break;
307 	}
308 	return 0;
309 }
310 
311 /**
312  * intel_vgpu_init_cfg_space - init vGPU configuration space when create vGPU
313  *
314  * @vgpu: a vGPU
315  * @primary: is the vGPU presented as primary
316  *
317  */
318 void intel_vgpu_init_cfg_space(struct intel_vgpu *vgpu,
319 			       bool primary)
320 {
321 	struct intel_gvt *gvt = vgpu->gvt;
322 	struct pci_dev *pdev = to_pci_dev(gvt->gt->i915->drm.dev);
323 	const struct intel_gvt_device_info *info = &gvt->device_info;
324 	u16 *gmch_ctl;
325 	u8 next;
326 
327 	memcpy(vgpu_cfg_space(vgpu), gvt->firmware.cfg_space,
328 	       info->cfg_space_size);
329 
330 	if (!primary) {
331 		vgpu_cfg_space(vgpu)[PCI_CLASS_DEVICE] =
332 			INTEL_GVT_PCI_CLASS_VGA_OTHER;
333 		vgpu_cfg_space(vgpu)[PCI_CLASS_PROG] =
334 			INTEL_GVT_PCI_CLASS_VGA_OTHER;
335 	}
336 
337 	/* Show guest that there isn't any stolen memory.*/
338 	gmch_ctl = (u16 *)(vgpu_cfg_space(vgpu) + INTEL_GVT_PCI_GMCH_CONTROL);
339 	*gmch_ctl &= ~(BDW_GMCH_GMS_MASK << BDW_GMCH_GMS_SHIFT);
340 
341 	intel_vgpu_write_pci_bar(vgpu, PCI_BASE_ADDRESS_2,
342 				 gvt_aperture_pa_base(gvt), true);
343 
344 	vgpu_cfg_space(vgpu)[PCI_COMMAND] &= ~(PCI_COMMAND_IO
345 					     | PCI_COMMAND_MEMORY
346 					     | PCI_COMMAND_MASTER);
347 	/*
348 	 * Clear the bar upper 32bit and let guest to assign the new value
349 	 */
350 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_1, 0, 4);
351 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_3, 0, 4);
352 	memset(vgpu_cfg_space(vgpu) + PCI_BASE_ADDRESS_4, 0, 8);
353 	memset(vgpu_cfg_space(vgpu) + INTEL_GVT_PCI_OPREGION, 0, 4);
354 
355 	vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_GTTMMIO].size =
356 		pci_resource_len(pdev, 0);
357 	vgpu->cfg_space.bar[INTEL_GVT_PCI_BAR_APERTURE].size =
358 		pci_resource_len(pdev, 2);
359 
360 	memset(vgpu_cfg_space(vgpu) + PCI_ROM_ADDRESS, 0, 4);
361 
362 	/* PM Support */
363 	vgpu->cfg_space.pmcsr_off = 0;
364 	if (vgpu_cfg_space(vgpu)[PCI_STATUS] & PCI_STATUS_CAP_LIST) {
365 		next = vgpu_cfg_space(vgpu)[PCI_CAPABILITY_LIST];
366 		do {
367 			if (vgpu_cfg_space(vgpu)[next + PCI_CAP_LIST_ID] == PCI_CAP_ID_PM) {
368 				vgpu->cfg_space.pmcsr_off = next + PCI_PM_CTRL;
369 				break;
370 			}
371 			next = vgpu_cfg_space(vgpu)[next + PCI_CAP_LIST_NEXT];
372 		} while (next);
373 	}
374 }
375 
376 /**
377  * intel_vgpu_reset_cfg_space - reset vGPU configuration space
378  *
379  * @vgpu: a vGPU
380  *
381  */
382 void intel_vgpu_reset_cfg_space(struct intel_vgpu *vgpu)
383 {
384 	u8 cmd = vgpu_cfg_space(vgpu)[PCI_COMMAND];
385 	bool primary = vgpu_cfg_space(vgpu)[PCI_CLASS_DEVICE] !=
386 				INTEL_GVT_PCI_CLASS_VGA_OTHER;
387 
388 	if (cmd & PCI_COMMAND_MEMORY) {
389 		trap_gttmmio(vgpu, false);
390 		map_aperture(vgpu, false);
391 	}
392 
393 	/**
394 	 * Currently we only do such reset when vGPU is not
395 	 * owned by any VM, so we simply restore entire cfg
396 	 * space to default value.
397 	 */
398 	intel_vgpu_init_cfg_space(vgpu, primary);
399 }
400