1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2022 Intel Corporation
4  */
5 
6 #include <linux/types.h>
7 
8 #include "gt/intel_gt.h"
9 #include "gt/intel_gt_print.h"
10 #include "intel_gsc_fw.h"
11 #include "intel_gsc_proxy.h"
12 #include "intel_gsc_uc.h"
13 #include "i915_drv.h"
14 #include "i915_reg.h"
15 
16 static void gsc_work(struct work_struct *work)
17 {
18 	struct intel_gsc_uc *gsc = container_of(work, typeof(*gsc), work);
19 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
20 	intel_wakeref_t wakeref;
21 	u32 actions;
22 	int ret;
23 
24 	wakeref = intel_runtime_pm_get(gt->uncore->rpm);
25 
26 	spin_lock_irq(gt->irq_lock);
27 	actions = gsc->gsc_work_actions;
28 	gsc->gsc_work_actions = 0;
29 	spin_unlock_irq(gt->irq_lock);
30 
31 	if (actions & GSC_ACTION_FW_LOAD) {
32 		ret = intel_gsc_uc_fw_upload(gsc);
33 		if (!ret)
34 			/* setup proxy on a new load */
35 			actions |= GSC_ACTION_SW_PROXY;
36 		else if (ret != -EEXIST)
37 			goto out_put;
38 
39 		/*
40 		 * The HuC auth can be done both before or after the proxy init;
41 		 * if done after, a proxy request will be issued and must be
42 		 * serviced before the authentication can complete.
43 		 * Since this worker also handles proxy requests, we can't
44 		 * perform an action that requires the proxy from within it and
45 		 * then stall waiting for it, because we'd be blocking the
46 		 * service path. Therefore, it is easier for us to load HuC
47 		 * first and do proxy later. The GSC will ack the HuC auth and
48 		 * then send the HuC proxy request as part of the proxy init
49 		 * flow.
50 		 * Note that we can only do the GSC auth if the GuC auth was
51 		 * successful.
52 		 */
53 		if (intel_uc_uses_huc(&gt->uc) &&
54 		    intel_huc_is_authenticated(&gt->uc.huc, INTEL_HUC_AUTH_BY_GUC))
55 			intel_huc_auth(&gt->uc.huc, INTEL_HUC_AUTH_BY_GSC);
56 	}
57 
58 	if (actions & GSC_ACTION_SW_PROXY) {
59 		if (!intel_gsc_uc_fw_init_done(gsc)) {
60 			gt_err(gt, "Proxy request received with GSC not loaded!\n");
61 			goto out_put;
62 		}
63 
64 		ret = intel_gsc_proxy_request_handler(gsc);
65 		if (ret) {
66 			if (actions & GSC_ACTION_FW_LOAD) {
67 				/*
68 				 * A proxy failure right after firmware load means the proxy-init
69 				 * step has failed so mark GSC as not usable after this
70 				 */
71 				drm_err(&gt->i915->drm,
72 					"GSC proxy handler failed to init\n");
73 				intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_LOAD_FAIL);
74 			}
75 			goto out_put;
76 		}
77 
78 		/* mark the GSC FW init as done the first time we run this */
79 		if (actions & GSC_ACTION_FW_LOAD) {
80 			/*
81 			 * If there is a proxy establishment error, the GSC might still
82 			 * complete the request handling cleanly, so we need to check the
83 			 * status register to check if the proxy init was actually successful
84 			 */
85 			if (intel_gsc_uc_fw_proxy_init_done(gsc, false)) {
86 				drm_dbg(&gt->i915->drm, "GSC Proxy initialized\n");
87 				intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_RUNNING);
88 			} else {
89 				drm_err(&gt->i915->drm,
90 					"GSC status reports proxy init not complete\n");
91 				intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_LOAD_FAIL);
92 			}
93 		}
94 	}
95 
96 out_put:
97 	intel_runtime_pm_put(gt->uncore->rpm, wakeref);
98 }
99 
100 static bool gsc_engine_supported(struct intel_gt *gt)
101 {
102 	intel_engine_mask_t mask;
103 
104 	/*
105 	 * We reach here from i915_driver_early_probe for the primary GT before
106 	 * its engine mask is set, so we use the device info engine mask for it.
107 	 * For other GTs we expect the GT-specific mask to be set before we
108 	 * call this function.
109 	 */
110 	GEM_BUG_ON(!gt_is_root(gt) && !gt->info.engine_mask);
111 
112 	if (gt_is_root(gt))
113 		mask = INTEL_INFO(gt->i915)->platform_engine_mask;
114 	else
115 		mask = gt->info.engine_mask;
116 
117 	return __HAS_ENGINE(mask, GSC0);
118 }
119 
120 void intel_gsc_uc_init_early(struct intel_gsc_uc *gsc)
121 {
122 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
123 
124 	/*
125 	 * GSC FW needs to be copied to a dedicated memory allocations for
126 	 * loading (see gsc->local), so we don't need to GGTT map the FW image
127 	 * itself into GGTT.
128 	 */
129 	intel_uc_fw_init_early(&gsc->fw, INTEL_UC_FW_TYPE_GSC, false);
130 	INIT_WORK(&gsc->work, gsc_work);
131 
132 	/* we can arrive here from i915_driver_early_probe for primary
133 	 * GT with it being not fully setup hence check device info's
134 	 * engine mask
135 	 */
136 	if (!gsc_engine_supported(gt)) {
137 		intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_NOT_SUPPORTED);
138 		return;
139 	}
140 
141 	gsc->wq = alloc_ordered_workqueue("i915_gsc", 0);
142 	if (!gsc->wq) {
143 		gt_err(gt, "failed to allocate WQ for GSC, disabling FW\n");
144 		intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_NOT_SUPPORTED);
145 	}
146 }
147 
148 static int gsc_allocate_and_map_vma(struct intel_gsc_uc *gsc, u32 size)
149 {
150 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
151 	struct drm_i915_gem_object *obj;
152 	struct i915_vma *vma;
153 	void __iomem *vaddr;
154 	int ret = 0;
155 
156 	/*
157 	 * The GSC FW doesn't immediately suspend after becoming idle, so there
158 	 * is a chance that it could still be awake after we successfully
159 	 * return from the  pci suspend function, even if there are no pending
160 	 * operations.
161 	 * The FW might therefore try to access memory for its suspend operation
162 	 * after the kernel has completed the HW suspend flow; this can cause
163 	 * issues if the FW is mapped in normal RAM memory, as some of the
164 	 * involved HW units might've already lost power.
165 	 * The driver must therefore avoid this situation and the recommended
166 	 * way to do so is to use stolen memory for the GSC memory allocation,
167 	 * because stolen memory takes a different path in HW and it is
168 	 * guaranteed to always work as long as the GPU itself is awake (which
169 	 * it must be if the GSC is awake).
170 	 */
171 	obj = i915_gem_object_create_stolen(gt->i915, size);
172 	if (IS_ERR(obj))
173 		return PTR_ERR(obj);
174 
175 	vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
176 	if (IS_ERR(vma)) {
177 		ret = PTR_ERR(vma);
178 		goto err;
179 	}
180 
181 	vaddr = i915_vma_pin_iomap(vma);
182 	i915_vma_unpin(vma);
183 	if (IS_ERR(vaddr)) {
184 		ret = PTR_ERR(vaddr);
185 		goto err;
186 	}
187 
188 	i915_vma_make_unshrinkable(vma);
189 
190 	gsc->local = vma;
191 	gsc->local_vaddr = vaddr;
192 
193 	return 0;
194 
195 err:
196 	i915_gem_object_put(obj);
197 	return ret;
198 }
199 
200 static void gsc_unmap_and_free_vma(struct intel_gsc_uc *gsc)
201 {
202 	struct i915_vma *vma = fetch_and_zero(&gsc->local);
203 
204 	if (!vma)
205 		return;
206 
207 	gsc->local_vaddr = NULL;
208 	i915_vma_unpin_iomap(vma);
209 	i915_gem_object_put(vma->obj);
210 }
211 
212 int intel_gsc_uc_init(struct intel_gsc_uc *gsc)
213 {
214 	static struct lock_class_key gsc_lock;
215 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
216 	struct intel_engine_cs *engine = gt->engine[GSC0];
217 	struct intel_context *ce;
218 	int err;
219 
220 	err = intel_uc_fw_init(&gsc->fw);
221 	if (err)
222 		goto out;
223 
224 	err = gsc_allocate_and_map_vma(gsc, SZ_4M);
225 	if (err)
226 		goto out_fw;
227 
228 	ce = intel_engine_create_pinned_context(engine, engine->gt->vm, SZ_4K,
229 						I915_GEM_HWS_GSC_ADDR,
230 						&gsc_lock, "gsc_context");
231 	if (IS_ERR(ce)) {
232 		gt_err(gt, "failed to create GSC CS ctx for FW communication\n");
233 		err =  PTR_ERR(ce);
234 		goto out_vma;
235 	}
236 
237 	gsc->ce = ce;
238 
239 	/* if we fail to init proxy we still want to load GSC for PM */
240 	intel_gsc_proxy_init(gsc);
241 
242 	intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_LOADABLE);
243 
244 	return 0;
245 
246 out_vma:
247 	gsc_unmap_and_free_vma(gsc);
248 out_fw:
249 	intel_uc_fw_fini(&gsc->fw);
250 out:
251 	gt_probe_error(gt, "GSC init failed %pe\n", ERR_PTR(err));
252 	return err;
253 }
254 
255 void intel_gsc_uc_fini(struct intel_gsc_uc *gsc)
256 {
257 	if (!intel_uc_fw_is_loadable(&gsc->fw))
258 		return;
259 
260 	flush_work(&gsc->work);
261 	if (gsc->wq) {
262 		destroy_workqueue(gsc->wq);
263 		gsc->wq = NULL;
264 	}
265 
266 	intel_gsc_proxy_fini(gsc);
267 
268 	if (gsc->ce)
269 		intel_engine_destroy_pinned_context(fetch_and_zero(&gsc->ce));
270 
271 	gsc_unmap_and_free_vma(gsc);
272 
273 	intel_uc_fw_fini(&gsc->fw);
274 }
275 
276 void intel_gsc_uc_flush_work(struct intel_gsc_uc *gsc)
277 {
278 	if (!intel_uc_fw_is_loadable(&gsc->fw))
279 		return;
280 
281 	flush_work(&gsc->work);
282 }
283 
284 void intel_gsc_uc_resume(struct intel_gsc_uc *gsc)
285 {
286 	if (!intel_uc_fw_is_loadable(&gsc->fw))
287 		return;
288 
289 	/*
290 	 * we only want to start the GSC worker from here in the actual resume
291 	 * flow and not during driver load. This is because GSC load is slow and
292 	 * therefore we want to make sure that the default state init completes
293 	 * first to not slow down the init thread. A separate call to
294 	 * intel_gsc_uc_load_start will ensure that the GSC is loaded during
295 	 * driver load.
296 	 */
297 	if (!gsc_uc_to_gt(gsc)->engine[GSC0]->default_state)
298 		return;
299 
300 	intel_gsc_uc_load_start(gsc);
301 }
302 
303 void intel_gsc_uc_load_start(struct intel_gsc_uc *gsc)
304 {
305 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
306 
307 	if (!intel_uc_fw_is_loadable(&gsc->fw) || intel_uc_fw_is_in_error(&gsc->fw))
308 		return;
309 
310 	if (intel_gsc_uc_fw_init_done(gsc))
311 		return;
312 
313 	spin_lock_irq(gt->irq_lock);
314 	gsc->gsc_work_actions |= GSC_ACTION_FW_LOAD;
315 	spin_unlock_irq(gt->irq_lock);
316 
317 	queue_work(gsc->wq, &gsc->work);
318 }
319 
320 void intel_gsc_uc_load_status(struct intel_gsc_uc *gsc, struct drm_printer *p)
321 {
322 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
323 	struct intel_uncore *uncore = gt->uncore;
324 	intel_wakeref_t wakeref;
325 
326 	if (!intel_gsc_uc_is_supported(gsc)) {
327 		drm_printf(p, "GSC not supported\n");
328 		return;
329 	}
330 
331 	if (!intel_gsc_uc_is_wanted(gsc)) {
332 		drm_printf(p, "GSC disabled\n");
333 		return;
334 	}
335 
336 	drm_printf(p, "GSC firmware: %s\n", gsc->fw.file_selected.path);
337 	if (gsc->fw.file_selected.path != gsc->fw.file_wanted.path)
338 		drm_printf(p, "GSC firmware wanted: %s\n", gsc->fw.file_wanted.path);
339 	drm_printf(p, "\tstatus: %s\n", intel_uc_fw_status_repr(gsc->fw.status));
340 
341 	drm_printf(p, "Release: %u.%u.%u.%u\n",
342 		   gsc->release.major, gsc->release.minor,
343 		   gsc->release.patch, gsc->release.build);
344 
345 	drm_printf(p, "Compatibility Version: %u.%u [min expected %u.%u]\n",
346 		   gsc->fw.file_selected.ver.major, gsc->fw.file_selected.ver.minor,
347 		   gsc->fw.file_wanted.ver.major, gsc->fw.file_wanted.ver.minor);
348 
349 	drm_printf(p, "SVN: %u\n", gsc->security_version);
350 
351 	with_intel_runtime_pm(uncore->rpm, wakeref) {
352 		u32 i;
353 
354 		for (i = 1; i <= 6; i++) {
355 			u32 status = intel_uncore_read(uncore,
356 						       HECI_FWSTS(MTL_GSC_HECI1_BASE, i));
357 			drm_printf(p, "HECI1 FWSTST%u = 0x%08x\n", i, status);
358 		}
359 	}
360 }
361